Beating a dead horse - 4.5 liter power
05-26-2005, 06:07 PM
#16
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>Of course!
COOL, thanks!
> I only have the one bottle, so hit me up early 'cause once it's gone...
OK, Friday PM at the hotel ?
> that is unless you know of a refill station nearby?
I will make some calls, if not I know a dentist office we can break in to...
COOL, thanks!
> I only have the one bottle, so hit me up early 'cause once it's gone...
OK, Friday PM at the hotel ?
> that is unless you know of a refill station nearby?
I will make some calls, if not I know a dentist office we can break in to...
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David Roberts
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05-27-2005, 02:16 AM
#17
Rennlist Member
was it a euro???
probably, or was probably not showing all that was done to it. Ive also played with timing, as its easy to do on the US Ljet system. advanced to 5-7over stock, and we gained 3ftlbs of torque, and lost 3 hp. not huge differences. ended up with stock timing +4 degrees for max HP.
MK
probably, or was probably not showing all that was done to it. Ive also played with timing, as its easy to do on the US Ljet system. advanced to 5-7over stock, and we gained 3ftlbs of torque, and lost 3 hp. not huge differences. ended up with stock timing +4 degrees for max HP.
MK
Originally Posted by MarkRobinson
A friend of mine was making 240rwhp/tq out of a 4.7 S motor, just ANSA exhaust & increased timing (a lot of it).
M.
M.
05-27-2005, 02:25 AM
#18
Rennlist Member
I think ive done more of a progression of mods to the US 4.7 than most.
we started at 175hp at the wheels (kind of weak, but very old motor) and ended up with 243hp at the rear.
first mods were remove cat, then, add headers , then 3.5" exhaust pipe, then we did euro cams and Intake (with throttle body) with fuel regs.
THEN, we changed the lower end to 5 liter and used the euro heads. HP was then up to 293 at the wheels, proving a couple of things. first, the AFM can support 100hp gains over stock with no changes or mods. next, it proved that the euro intake does make a ton of difference.
On the 4.5 liter scot weisach, we ended up with 219 hp at the wheels with significant gains over the header only mod, based on 60-100times.
the 4.5 liter that didnt show the gains we saw, could have been due to the throttle body not being a euro . (not as large) the main gain of the euro intake is the throttle body diameter . 3.3" vs 2.7" stock US.
sure the AFM is a bottle neck, but based on the CIS versions of the 5 liter vs the Ljet version that i had, all the HP to the wheels seemed to be pretty close.
mk
we started at 175hp at the wheels (kind of weak, but very old motor) and ended up with 243hp at the rear.
first mods were remove cat, then, add headers , then 3.5" exhaust pipe, then we did euro cams and Intake (with throttle body) with fuel regs.
THEN, we changed the lower end to 5 liter and used the euro heads. HP was then up to 293 at the wheels, proving a couple of things. first, the AFM can support 100hp gains over stock with no changes or mods. next, it proved that the euro intake does make a ton of difference.
On the 4.5 liter scot weisach, we ended up with 219 hp at the wheels with significant gains over the header only mod, based on 60-100times.
the 4.5 liter that didnt show the gains we saw, could have been due to the throttle body not being a euro . (not as large) the main gain of the euro intake is the throttle body diameter . 3.3" vs 2.7" stock US.
sure the AFM is a bottle neck, but based on the CIS versions of the 5 liter vs the Ljet version that i had, all the HP to the wheels seemed to be pretty close.
mk
Originally Posted by John V
no, just this topic appears to dead end in that short of forced induction, or change in displacement, I haven't seen any consistent mods that produce measurable results. Many have opened up the exhaust and seen 10-20 HP (many with a loss of low end torque). And some have tried some variation of intake mods (cams, euro intake components, cam timimg) but no "consistent" appreciable gains that I can recall. Mark Kibort as well as some other have posted some nice numbers but there was a transition to 4.7 liters in the mix. I don't think I've seen RWHP #'s above 200 on the 4.5L without forced induction or NOS. Am I wrong?
05-27-2005, 02:30 AM
#19
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by the way, the gains we saw for just the cams and euro intake were 43hp.
there was NO upgrade to 4.7 "in the mix". it was a 4.7 to start (ie US '84)
Plus, NONE of any of the gains came at a cost of anything@!!!! the only thing interesting with all the dyno runs , and at the time i was dynoing the car all the time, was that the torque didnt go up with the cams , the hp did!
However with the change in exhaust, from stock , to remove cat , to headers, 3.5" etc, we saw gains that just shifted the entire hp and torque curve up proportionately. (ie hp gains were generally about 7 hp and 7ft bs for the two major changes in exhaust. headers and 3.5" tube replacing stock 2.7" with bypass tube with meg collector)
mk
there was NO upgrade to 4.7 "in the mix". it was a 4.7 to start (ie US '84)
Plus, NONE of any of the gains came at a cost of anything@!!!! the only thing interesting with all the dyno runs , and at the time i was dynoing the car all the time, was that the torque didnt go up with the cams , the hp did!
However with the change in exhaust, from stock , to remove cat , to headers, 3.5" etc, we saw gains that just shifted the entire hp and torque curve up proportionately. (ie hp gains were generally about 7 hp and 7ft bs for the two major changes in exhaust. headers and 3.5" tube replacing stock 2.7" with bypass tube with meg collector)
mk
Originally Posted by John V
I haven't seen any consistent mods that produce measurable results. Many have opened up the exhaust and seen 10-20 HP (many with a loss of low end torque). And some have tried some variation of intake mods (cams, euro intake components, cam timimg) but no "consistent" appreciable gains that I can recall. Mark Kibort as well as some other have posted some nice numbers but there was a transition to 4.7 liters in the mix. I don't think I've seen RWHP #'s above 200 on the 4.5L without forced induction or NOS. Am I wrong?
05-27-2005, 02:34 AM
#20
Three Wheelin'
So putting 85-86 factory exhaust manifolds on yield some increase over the stock 80 model ones? Give me more info on the euro throttle body ar AFM? What do I need to do to do this change?
05-27-2005, 09:49 AM
#22
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Mark,
your numbers are no doubt impressive. The problem is that many of those numbers are based upon 4.7 liters of displacement. I don't know what exact effect that has ie.; a 4.7 L running at 75% volumetric efficiency has more power potential than 4.5 running at 78% VE and the 5.0 l has still more than both at even 72% VE. I believe (opinion) that the additional displacement will mask (to a larger degree) any TB and AFM restrictions becuase its drawing in a larger gulp of air with each intake stroke , even through the same intake tract.
I've run the numbers on each piece of the intake and while the USA tract is smaller than the euro S, I'm not convinced adding the euro intake will help significantly. As far as I can tell, the smallest restriction by far is the valve aperture (related to cam and valve size). That being the case, it would make sense to me that any intake and exhaust mods are going to yeild very marginal gains without addressing that problem (as was partially the case with Jon F). The AFM is the next smallest at around 4.1 square inches (but with the additional restriction of a spring loaded barn door). While the USA TB is smaller than the euro, its still about 140% the area of the AFM at almost 5.75 sq. in.. And, the USA runners are more than 200 % larger than the USA TB @ around 1.7 sq in each or 13.6 sq. in total. I don't know the exact formula for determining area to CFM prediction but I used some of Holleys TB data (size to cfm potential) to back drive a number. They did not publish the test method or pressure / drop values just area and CFM potential. Using this crude formula, the AFM apperature would only be capable of 470 CFM while the USA TB would be capable of 652 CFM and the USA runners 1500 CFM.
So, while adding a larger intake tract could present a more efficient path for air movement, it may actually decrease air velocity if the valves can't draw in more air via the intake stroke. Since after the valves, the AFM is the next most restrictive apperture, changing anything between those 2 points doesn't appear logical towards any significant gains. In haven't seen anything to prove or disprove this notion. The AFM has been nearly impossible to work around due to the voltages and L-jet controller so that begs the question....wouldn't bolting a 600 CFM carb on top of a simple intake prove once and for all if the intake tract is a source of potential gains?? I think it could be, but not until the valve apperture is addressed.
your numbers are no doubt impressive. The problem is that many of those numbers are based upon 4.7 liters of displacement. I don't know what exact effect that has ie.; a 4.7 L running at 75% volumetric efficiency has more power potential than 4.5 running at 78% VE and the 5.0 l has still more than both at even 72% VE. I believe (opinion) that the additional displacement will mask (to a larger degree) any TB and AFM restrictions becuase its drawing in a larger gulp of air with each intake stroke , even through the same intake tract.
I've run the numbers on each piece of the intake and while the USA tract is smaller than the euro S, I'm not convinced adding the euro intake will help significantly. As far as I can tell, the smallest restriction by far is the valve aperture (related to cam and valve size). That being the case, it would make sense to me that any intake and exhaust mods are going to yeild very marginal gains without addressing that problem (as was partially the case with Jon F). The AFM is the next smallest at around 4.1 square inches (but with the additional restriction of a spring loaded barn door). While the USA TB is smaller than the euro, its still about 140% the area of the AFM at almost 5.75 sq. in.. And, the USA runners are more than 200 % larger than the USA TB @ around 1.7 sq in each or 13.6 sq. in total. I don't know the exact formula for determining area to CFM prediction but I used some of Holleys TB data (size to cfm potential) to back drive a number. They did not publish the test method or pressure / drop values just area and CFM potential. Using this crude formula, the AFM apperature would only be capable of 470 CFM while the USA TB would be capable of 652 CFM and the USA runners 1500 CFM.
So, while adding a larger intake tract could present a more efficient path for air movement, it may actually decrease air velocity if the valves can't draw in more air via the intake stroke. Since after the valves, the AFM is the next most restrictive apperture, changing anything between those 2 points doesn't appear logical towards any significant gains. In haven't seen anything to prove or disprove this notion. The AFM has been nearly impossible to work around due to the voltages and L-jet controller so that begs the question....wouldn't bolting a 600 CFM carb on top of a simple intake prove once and for all if the intake tract is a source of potential gains?? I think it could be, but not until the valve apperture is addressed.
05-27-2005, 01:15 PM
#23
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I have dyno sheets that show the euro runners and TB make little to no difference on a NA 4.5 liter US. The euro cams are a different story all together....+30 HP up top and a bit more torque...the differences start at about 3800-4000. The 80-82 cams are really bad for top end power, there is no overlap at all and the lift is much lower than even the 78-79 cams or the Euro cams. The 78/79 have 0.040" more lift and the euro have a full 0.080" more lift. The bang is in the camshafts.
I am more than willing to supply you guys with manifolds for a K-26 install. Believe me this wakes the motor up big time, even with the crappy camshafts. Buy the manifolds and intercooler from me, source some cheap K-26 turbos and do the plumbing yourself and make a monster on a low budget! I have my jigs and will be looking to make a few sets of manifolds so the costs will be reasonable. I don't have limited slip on the new TT, but with the small K-24s and a VERY heavy right foot I have seen the car put down a solid 50-75 feet of black rubber with a 245 tire. Remember, I am running a 3-spd AT on this car.
I'm sure switching to a low restriction multi-throttle setup would work...but the cost would be quite high for the returns
I am more than willing to supply you guys with manifolds for a K-26 install. Believe me this wakes the motor up big time, even with the crappy camshafts. Buy the manifolds and intercooler from me, source some cheap K-26 turbos and do the plumbing yourself and make a monster on a low budget! I have my jigs and will be looking to make a few sets of manifolds so the costs will be reasonable. I don't have limited slip on the new TT, but with the small K-24s and a VERY heavy right foot I have seen the car put down a solid 50-75 feet of black rubber with a 245 tire. Remember, I am running a 3-spd AT on this car.
I'm sure switching to a low restriction multi-throttle setup would work...but the cost would be quite high for the returns
05-27-2005, 02:27 PM
#24
Rennlist Member
one thing you are failing to take into consideration, is the pressure drop through a smaller air flow area, and the length of that area. I know too well all the areas of the US system. your right, the gains on a 4.5 liter should be less than a 4.7, but not that much less. (due to the points below) HOWEVER, dont also forget that the valve area and the AFM area are at the ends of the air flow system, with 2 intake valves open at any given time (area of 43 or 45mm X 2)
if you look at the entire path of the US intake it starts out as:
4.1square in at the AFM
7 square in at the "U" going to the TB
4.9 square in at the throttle PLATE
3.52 square in for two runners (2.01 sq" each at 1.5" diameter)
4.48 square for two valves (43mm each)
the flow is disrupted by venturi effects along the way and smaller areas.
On the US AFM but with euro stuff (TB , runners and valves) it looks like this:
4.14 AFM
7.06 "U"
7.06 "euro throttle plate"
4 for two "euro runnners at 1.6" diameter"
5 for two "euro 45mm valves)
the euro buys 50% more throttle area, 16% more runner area and 11% more at the valves.
this in my tests have proven to be quite good on the 4.7 and i imagine some fraction of that for a 4.5 . the reason we lower gains on the one 4.5, was that the throttle body was not full euro spec. scots car is 219hp at the wheels with this set up and was much weaker than my 79 full stock, even with a high flow cat (no headers, etc) it finally came to life with all the euro intake stuff, but not the euro heads and cams.
on my 4.7, with the intake and alone, we saw a solid 43hp!!!(over stock US '84 stuff) now, how much of it was thecams. call it half??? i dont know. how much was it them working together, call it another 25%. worst case, the euro intake is probably worth about 15hp
so, to summerize. the restrictions are multiple in the system. sure the AFM and valves are the neck down, so, what you try to do is reduce the pressure drops accross the intake length. also, the AFM spring loaded valve provides negligible restriction. (as proved by tests by bosche) but the small 4" square area is the problem there. However, it has a nice inlet, bell mouthed in all, so it has less losses that a much bigger inlet that was not as well designed. often guys that work on heads, see all sorts of small ports that flow better than larger ports depending on their shapes and angles. very complicated stuff in this area. so, its more that meets the eyes or calculator. this is why the ALMS cars can get nearly 600hp through two openings the size of the US AFM.
its all about reducing pressure drops!
mk
as a side note look at andersons and Fans set up. they didnt change valves , but they are certainly the bottleneck for their set ups, yet, with a TB change and the CF intake, suddenly, they got 85hp!!!!!!!!! Their valves where way under the area of the rest of the system, yet they improved the losses mid stream, plus any other number of synergistic factors for the flow in the system that was improved, and it yielded much more mass flow throught the system. 85hp on top of 420 at the wheels is significant. So, it can be done and makes perfect sense.
if you look at the entire path of the US intake it starts out as:
4.1square in at the AFM
7 square in at the "U" going to the TB
4.9 square in at the throttle PLATE
3.52 square in for two runners (2.01 sq" each at 1.5" diameter)
4.48 square for two valves (43mm each)
the flow is disrupted by venturi effects along the way and smaller areas.
On the US AFM but with euro stuff (TB , runners and valves) it looks like this:
4.14 AFM
7.06 "U"
7.06 "euro throttle plate"
4 for two "euro runnners at 1.6" diameter"
5 for two "euro 45mm valves)
the euro buys 50% more throttle area, 16% more runner area and 11% more at the valves.
this in my tests have proven to be quite good on the 4.7 and i imagine some fraction of that for a 4.5 . the reason we lower gains on the one 4.5, was that the throttle body was not full euro spec. scots car is 219hp at the wheels with this set up and was much weaker than my 79 full stock, even with a high flow cat (no headers, etc) it finally came to life with all the euro intake stuff, but not the euro heads and cams.
on my 4.7, with the intake and alone, we saw a solid 43hp!!!(over stock US '84 stuff) now, how much of it was thecams. call it half??? i dont know. how much was it them working together, call it another 25%. worst case, the euro intake is probably worth about 15hp
so, to summerize. the restrictions are multiple in the system. sure the AFM and valves are the neck down, so, what you try to do is reduce the pressure drops accross the intake length. also, the AFM spring loaded valve provides negligible restriction. (as proved by tests by bosche) but the small 4" square area is the problem there. However, it has a nice inlet, bell mouthed in all, so it has less losses that a much bigger inlet that was not as well designed. often guys that work on heads, see all sorts of small ports that flow better than larger ports depending on their shapes and angles. very complicated stuff in this area. so, its more that meets the eyes or calculator. this is why the ALMS cars can get nearly 600hp through two openings the size of the US AFM.
its all about reducing pressure drops!
mk
as a side note look at andersons and Fans set up. they didnt change valves , but they are certainly the bottleneck for their set ups, yet, with a TB change and the CF intake, suddenly, they got 85hp!!!!!!!!! Their valves where way under the area of the rest of the system, yet they improved the losses mid stream, plus any other number of synergistic factors for the flow in the system that was improved, and it yielded much more mass flow throught the system. 85hp on top of 420 at the wheels is significant. So, it can be done and makes perfect sense.
Originally Posted by John V
Mark,
your numbers are no doubt impressive. The problem is that many of those numbers are based upon 4.7 liters of displacement. I don't know what exact effect that has ie.; a 4.7 L running at 75% volumetric efficiency has more power potential than 4.5 running at 78% VE and the 5.0 l has still more than both at even 72% VE. I believe (opinion) that the additional displacement will mask (to a larger degree) any TB and AFM restrictions becuase its drawing in a larger gulp of air with each intake stroke , even through the same intake tract.
I've run the numbers on each piece of the intake and while the USA tract is smaller than the euro S, I'm not convinced adding the euro intake will help significantly. As far as I can tell, the smallest restriction by far is the valve aperture (related to cam and valve size). That being the case, it would make sense to me that any intake and exhaust mods are going to yeild very marginal gains without addressing that problem (as was partially the case with Jon F). The AFM is the next smallest at around 4.1 square inches (but with the additional restriction of a spring loaded barn door). While the USA TB is smaller than the euro, its still about 140% the area of the AFM at almost 5.75 sq. in.. And, the USA runners are more than 200 % larger than the USA TB @ around 1.7 sq in each or 13.6 sq. in total. I don't know the exact formula for determining area to CFM prediction but I used some of Holleys TB data (size to cfm potential) to back drive a number. They did not publish the test method or pressure / drop values just area and CFM potential. Using this crude formula, the AFM apperature would only be capable of 470 CFM while the USA TB would be capable of 652 CFM and the USA runners 1500 CFM.
So, while adding a larger intake tract could present a more efficient path for air movement, it may actually decrease air velocity if the valves can't draw in more air via the intake stroke. Since after the valves, the AFM is the next most restrictive apperture, changing anything between those 2 points doesn't appear logical towards any significant gains. In haven't seen anything to prove or disprove this notion. The AFM has been nearly impossible to work around due to the voltages and L-jet controller so that begs the question....wouldn't bolting a 600 CFM carb on top of a simple intake prove once and for all if the intake tract is a source of potential gains?? I think it could be, but not until the valve apperture is addressed.
your numbers are no doubt impressive. The problem is that many of those numbers are based upon 4.7 liters of displacement. I don't know what exact effect that has ie.; a 4.7 L running at 75% volumetric efficiency has more power potential than 4.5 running at 78% VE and the 5.0 l has still more than both at even 72% VE. I believe (opinion) that the additional displacement will mask (to a larger degree) any TB and AFM restrictions becuase its drawing in a larger gulp of air with each intake stroke , even through the same intake tract.
I've run the numbers on each piece of the intake and while the USA tract is smaller than the euro S, I'm not convinced adding the euro intake will help significantly. As far as I can tell, the smallest restriction by far is the valve aperture (related to cam and valve size). That being the case, it would make sense to me that any intake and exhaust mods are going to yeild very marginal gains without addressing that problem (as was partially the case with Jon F). The AFM is the next smallest at around 4.1 square inches (but with the additional restriction of a spring loaded barn door). While the USA TB is smaller than the euro, its still about 140% the area of the AFM at almost 5.75 sq. in.. And, the USA runners are more than 200 % larger than the USA TB @ around 1.7 sq in each or 13.6 sq. in total. I don't know the exact formula for determining area to CFM prediction but I used some of Holleys TB data (size to cfm potential) to back drive a number. They did not publish the test method or pressure / drop values just area and CFM potential. Using this crude formula, the AFM apperature would only be capable of 470 CFM while the USA TB would be capable of 652 CFM and the USA runners 1500 CFM.
So, while adding a larger intake tract could present a more efficient path for air movement, it may actually decrease air velocity if the valves can't draw in more air via the intake stroke. Since after the valves, the AFM is the next most restrictive apperture, changing anything between those 2 points doesn't appear logical towards any significant gains. In haven't seen anything to prove or disprove this notion. The AFM has been nearly impossible to work around due to the voltages and L-jet controller so that begs the question....wouldn't bolting a 600 CFM carb on top of a simple intake prove once and for all if the intake tract is a source of potential gains?? I think it could be, but not until the valve apperture is addressed.
05-27-2005, 02:52 PM
#25
Get the costs nailed down on the manifolds John - I'm looking at a couple thousand for either a rear mounted turbo or a SC for the 78.
I should have over 225 to the wheels on the 4.5L I built - I hope closer to 250. Euro intake and TB, 78 cams, massaged heads and polished valves with new seats in the heads. NEW 10:1 pistons with rings. MSDS headers into a dual (or single if I go towards the rear turbo). NO MAF or Barn Door - straight shot into engine from Air box. MAP based tuning, with no distributor and high res maps for ignition and injection - but batch still - bank/bank.
Just remember that people got quite a bit of power out of Ford's 289 engines. 289 is close to 4.5, just a bit more.
I should have over 225 to the wheels on the 4.5L I built - I hope closer to 250. Euro intake and TB, 78 cams, massaged heads and polished valves with new seats in the heads. NEW 10:1 pistons with rings. MSDS headers into a dual (or single if I go towards the rear turbo). NO MAF or Barn Door - straight shot into engine from Air box. MAP based tuning, with no distributor and high res maps for ignition and injection - but batch still - bank/bank.
Just remember that people got quite a bit of power out of Ford's 289 engines. 289 is close to 4.5, just a bit more.
05-27-2005, 03:36 PM
#26
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Mark,
First let me say that I'm not an expert and, I appreciate all the info you've posted. Your one of the motivators that pushes us OB for better and thats a good thing. Unfortunatly, some of what you profess has been difficult to quatify by others, especially in the 4.5 L world. I've followed most of it and to be honest I'm left with "doubts". I don't "doubt" your numbers, just the percentages of impact you have attributed to certain mods.
I think most folks understand that many factors effect flow including pressure, area, bends and surface irregularities. However, other than pressure, all else being equal, area is likely the next principle contributer. Where I think your numbers and others expectations have gone astray is in evaluating the valves impact in the equation. In using the valves diameter (43 or 45 mm) x 2, you are not taking into account that this aperture , (unlike any other in the equation) is not fully open for flow 1) because of differences in cam lift and 2) becuase of cam duration and 3) because the valve itself obstructs laminar flow through it (unlike a throttle plate). In deed those 3 factors are more limiting to a large degree than any other single factor, including the AFM. I think that is a critical key that reconciles yours and others experiences.
In your scenerio, the USA valves are less restrictive than the AFM and the runners while the Euro S valves are even less restrictive than both the USA TB and AFM. Forgive me for saying so but I think that is incorrect. I'd venture to say that even Euro S valves are far more of a restriction than anything in the USA intake system including the AFM. Even worst for the USA valves and cam. Consider that they flow not in a constant pattern equal their diameter as you calculate, but in a variable ribbon pattern equal to the circumferance of the valve multiplied by the lift of the cam (which drastically reduces the available area). Then, that reduced area is further truncated by the cams duration. If we can agree that this is the case, then I think one would have to conclude that they are the principle restriction in the system by a large margin. Thats not to say improvements can't be made to the rest of the system but until that one is addressed, the others will produce very modest gains. I think that is exactly what has been shown in the real world?
I see brendan has posted while I was writing... my point to all this is that the valves and cams are whats holding our engines back, not the runner or the TB. I personally believe the AFM has larger impact than either the runners or the TB and woul bet that an improvemnt there would show better results than the euro tb and runner did, but still not as substantial as any work on the valves.
First let me say that I'm not an expert and, I appreciate all the info you've posted. Your one of the motivators that pushes us OB for better and thats a good thing. Unfortunatly, some of what you profess has been difficult to quatify by others, especially in the 4.5 L world. I've followed most of it and to be honest I'm left with "doubts". I don't "doubt" your numbers, just the percentages of impact you have attributed to certain mods.
I think most folks understand that many factors effect flow including pressure, area, bends and surface irregularities. However, other than pressure, all else being equal, area is likely the next principle contributer. Where I think your numbers and others expectations have gone astray is in evaluating the valves impact in the equation. In using the valves diameter (43 or 45 mm) x 2, you are not taking into account that this aperture , (unlike any other in the equation) is not fully open for flow 1) because of differences in cam lift and 2) becuase of cam duration and 3) because the valve itself obstructs laminar flow through it (unlike a throttle plate). In deed those 3 factors are more limiting to a large degree than any other single factor, including the AFM. I think that is a critical key that reconciles yours and others experiences.
In your scenerio, the USA valves are less restrictive than the AFM and the runners while the Euro S valves are even less restrictive than both the USA TB and AFM. Forgive me for saying so but I think that is incorrect. I'd venture to say that even Euro S valves are far more of a restriction than anything in the USA intake system including the AFM. Even worst for the USA valves and cam. Consider that they flow not in a constant pattern equal their diameter as you calculate, but in a variable ribbon pattern equal to the circumferance of the valve multiplied by the lift of the cam (which drastically reduces the available area). Then, that reduced area is further truncated by the cams duration. If we can agree that this is the case, then I think one would have to conclude that they are the principle restriction in the system by a large margin. Thats not to say improvements can't be made to the rest of the system but until that one is addressed, the others will produce very modest gains. I think that is exactly what has been shown in the real world?
I see brendan has posted while I was writing... my point to all this is that the valves and cams are whats holding our engines back, not the runner or the TB. I personally believe the AFM has larger impact than either the runners or the TB and woul bet that an improvemnt there would show better results than the euro tb and runner did, but still not as substantial as any work on the valves.
Last edited by John V; 05-27-2005 at 03:55 PM.
05-27-2005, 04:49 PM
#28
The engine is complete, and ready to be installed and loomed for the new electrics in the car. I didn't built it for boost, but it may get up to about 10 or so psi even with its high compression if I can get the charge cooled enough with intercoolers and or meth/water injection.
The entire engine was disassembled and balanced/reworked. New rod bolts, new small end bushings on the rods, new mains, new rod bearings. The block was cleaned up and the bores were re-lapped to bring the alusil out again. Heads were decked, rebuilt with new seats and guides, and I did some polishing on the exhaust valves for flow over the margins. The intake valves also were buzzed a bit at the leading edge for flow. The heads were port matched to the Euro runners and gaskets, so there is no more lip there.
I grafted S4 fuel rails on the Euro intake with 39lb injectors (just in case I guess) so I wouldn't have fueling issues. Opened up the holes for the injectors IN the rail, and the will be -8 line from the tank to the engine and back. That should be good for whatever I do.
I will be running the megasquirt www.msefi.com , so I will have tunability for most instances, and a MAP based tune, so no problems with boost. I have the FORD EDIS system all reasy to install and wire, so that is a dual coil system run from one 36-1 timing wheel that I THOUGHT I would put on the pulley, but it turns out a perfect place is on the outside of the flywheel as I can make the perfect sized wheel to fit there at www.emachineshop.com for about 180 bucks or so. So I am not tied then to any pulley or wiring at the front of the engine if I go Centrifugal or whatever. ( I have a used V-1 anyway).
I spent quite a bit of time on the valves John. I was THINKING of doing Chevy valves, but I chickened out, and just did the work I described above on the entire port/valve combination for good smooth flow. I stuck Chevy valve springs in there for more shut force at the high rpms (only 6700 or so unless I show power above that) That was a trial - larger spring seats, custom valve spring shims, etc. Hope it all works!
For that reason I put in the HTD belt system from the later cars and basically almost new cams gears.
The 10:1 compression pistons were what kept me in the 4.5L build. If I hadn't found those for the price I did (250 shipped from a guy on ebay - NEW mahl boxes, unopened old stock) I would have bit on a 5.0l block. But I probably now have one of the last REALLY rebuilt 4.5L engines around. People just chuck them now and buy bigger. It won't be the first time I'm called crazy.
Looking at your longer post, I wanted bigger valves, but its a street engine, and I was concerned about port velocity and low range power. I guess well see in the end. I plan a dyno run without boost just to see what I really built.
The entire engine was disassembled and balanced/reworked. New rod bolts, new small end bushings on the rods, new mains, new rod bearings. The block was cleaned up and the bores were re-lapped to bring the alusil out again. Heads were decked, rebuilt with new seats and guides, and I did some polishing on the exhaust valves for flow over the margins. The intake valves also were buzzed a bit at the leading edge for flow. The heads were port matched to the Euro runners and gaskets, so there is no more lip there.
I grafted S4 fuel rails on the Euro intake with 39lb injectors (just in case I guess) so I wouldn't have fueling issues. Opened up the holes for the injectors IN the rail, and the will be -8 line from the tank to the engine and back. That should be good for whatever I do.
I will be running the megasquirt www.msefi.com , so I will have tunability for most instances, and a MAP based tune, so no problems with boost. I have the FORD EDIS system all reasy to install and wire, so that is a dual coil system run from one 36-1 timing wheel that I THOUGHT I would put on the pulley, but it turns out a perfect place is on the outside of the flywheel as I can make the perfect sized wheel to fit there at www.emachineshop.com for about 180 bucks or so. So I am not tied then to any pulley or wiring at the front of the engine if I go Centrifugal or whatever. ( I have a used V-1 anyway).
I spent quite a bit of time on the valves John. I was THINKING of doing Chevy valves, but I chickened out, and just did the work I described above on the entire port/valve combination for good smooth flow. I stuck Chevy valve springs in there for more shut force at the high rpms (only 6700 or so unless I show power above that) That was a trial - larger spring seats, custom valve spring shims, etc. Hope it all works!
For that reason I put in the HTD belt system from the later cars and basically almost new cams gears.
The 10:1 compression pistons were what kept me in the 4.5L build. If I hadn't found those for the price I did (250 shipped from a guy on ebay - NEW mahl boxes, unopened old stock) I would have bit on a 5.0l block. But I probably now have one of the last REALLY rebuilt 4.5L engines around. People just chuck them now and buy bigger. It won't be the first time I'm called crazy.
Looking at your longer post, I wanted bigger valves, but its a street engine, and I was concerned about port velocity and low range power. I guess well see in the end. I plan a dyno run without boost just to see what I really built.
05-27-2005, 05:11 PM
#29
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I've been looking at the megasquirt (towards dumping the AFM). Are you going wiht their new duaghter card for better resolution?
Man, I think your doing it right! I can't wait to see what she does on the dyno! I've often though of using the Chevy valves (I'm looking at some head work right now) but theres still some question of just how much bigger you can go due to valve spacing and bore clearance. On that note... did you do anything with the steel sleeve on the exhaust ports? Any idea why thats there? It looks like a you could gain some area there and othert aluminum heads (american perfromance stuff) I've seen don't have that. Are you concerned about the heavuer valve srpings adding to timimg belt stretch?
Man, I think your doing it right! I can't wait to see what she does on the dyno! I've often though of using the Chevy valves (I'm looking at some head work right now) but theres still some question of just how much bigger you can go due to valve spacing and bore clearance. On that note... did you do anything with the steel sleeve on the exhaust ports? Any idea why thats there? It looks like a you could gain some area there and othert aluminum heads (american perfromance stuff) I've seen don't have that. Are you concerned about the heavuer valve srpings adding to timimg belt stretch?
05-27-2005, 05:18 PM
#30
I will probably try and tune without the duaghter card as I do not believe I get the higher resolution since I have 'n extra for the code - which I am using to tune the ignition.
What years do the exhaust ports have a steel sleeve on? Mine do not, and neither did my old 81?
Chevy valves are doable. My mechanic buddy did them on his 83 euro. But for him, and the 4.7, chevy valves = bore wall cutouts. Nice huh? A nice chunk out of the side top of the acutal tower to get those valves in there. And the CIS can't fuel it above 4k... That was 2 years ago. Looks like chevy valves are only for 5.0 where you will have more bore wall room.
I AM concerned about the belt. But there will be no valve piston contact if it snaps. I went a BIT higher on spring tension but not crazy. I just don't want any float at 6700 shifts.
What years do the exhaust ports have a steel sleeve on? Mine do not, and neither did my old 81?
Chevy valves are doable. My mechanic buddy did them on his 83 euro. But for him, and the 4.7, chevy valves = bore wall cutouts. Nice huh? A nice chunk out of the side top of the acutal tower to get those valves in there. And the CIS can't fuel it above 4k... That was 2 years ago. Looks like chevy valves are only for 5.0 where you will have more bore wall room.
I AM concerned about the belt. But there will be no valve piston contact if it snaps. I went a BIT higher on spring tension but not crazy. I just don't want any float at 6700 shifts.