The quest for horsepower has begun
01-27-2002, 09:26 PM
#16
[quote]Originally posted by steve cattaneo:
<strong>I'm waiting to hear from extrudehone on a price to flow test and rework a S4 intake manifold.</strong><hr></blockquote>
They told me $600 to get one extrude honed when I contacted them recenty.
<strong>I'm waiting to hear from extrudehone on a price to flow test and rework a S4 intake manifold.</strong><hr></blockquote>
They told me $600 to get one extrude honed when I contacted them recenty.
01-27-2002, 11:51 PM
#17
Steve,
Don't use total seal rings on the 928 engine. I learned that one the hard way and had to rehone my block.
If you're going with 11.1:1 compression, you might want to upgrade to a tuneable engine management system with a good knock sensor.
Matching the J&E pistons to work in the Alusil block was/is a pain and the piston coating was an even greater pain.
If I had the whole process to do over, I would supercharge and intercool the engine and pump-up the boost. When/if the engine blows just bolt on another short-block and do it all over again. The U.S. short-blocks have become relatively inexpensive but those engine modifications will not be cheap.
Jim Nowak
Don't use total seal rings on the 928 engine. I learned that one the hard way and had to rehone my block.
If you're going with 11.1:1 compression, you might want to upgrade to a tuneable engine management system with a good knock sensor.
Matching the J&E pistons to work in the Alusil block was/is a pain and the piston coating was an even greater pain.
If I had the whole process to do over, I would supercharge and intercool the engine and pump-up the boost. When/if the engine blows just bolt on another short-block and do it all over again. The U.S. short-blocks have become relatively inexpensive but those engine modifications will not be cheap.
Jim Nowak
01-28-2002, 02:03 AM
#18
Steve C.,
Put 3200 miles on Pattycakes since the
Summer Flame Thrower Fest on the K&N filters.
I had tapped and wiped the excess oil off of the filter and after cleanup of throttle body wiped it dry prior to filter installation.
Results: zero oil misting, no debris, no grit,
no dust, ... nothing.
I then noticed it was a calm night, 32% humidity.
Here comes the flame magnet...
Everything from the intake horns to filter cover/filter/retaining bands came off.
And proceeded with the evening Camaro/Mustang.
Short version: the larger the amount of unrestricted air produced a smoother, faster revving engine. Back home checked for dirt and reinstalled everything. My hide-a-way cul de sac had an incredible amount of Camaro/Stang/Firebird and hot rod pick up traffic to day. My neighbors were pissed. I guess I trounced everything last night. And they finally, me!!! Merde!
I think you would be doing your engine project a grave disservice if you didn't do a little machine work/experimentation.
I'm looking around for an old 390 CI ford cover and filter set-up. That skinny, long oval for the trip carb set up would be ideal and there should be room. If your big valves can't draw enough air to those big pistons all is for naught.
Give the air feed some thought if you haven't already.
John S. and Pattycakes - still looking for a sibling.
Put 3200 miles on Pattycakes since the
Summer Flame Thrower Fest on the K&N filters.
I had tapped and wiped the excess oil off of the filter and after cleanup of throttle body wiped it dry prior to filter installation.
Results: zero oil misting, no debris, no grit,
no dust, ... nothing.
I then noticed it was a calm night, 32% humidity.
Here comes the flame magnet...
Everything from the intake horns to filter cover/filter/retaining bands came off.
And proceeded with the evening Camaro/Mustang.
Short version: the larger the amount of unrestricted air produced a smoother, faster revving engine. Back home checked for dirt and reinstalled everything. My hide-a-way cul de sac had an incredible amount of Camaro/Stang/Firebird and hot rod pick up traffic to day. My neighbors were pissed. I guess I trounced everything last night. And they finally, me!!! Merde!
I think you would be doing your engine project a grave disservice if you didn't do a little machine work/experimentation.
I'm looking around for an old 390 CI ford cover and filter set-up. That skinny, long oval for the trip carb set up would be ideal and there should be room. If your big valves can't draw enough air to those big pistons all is for naught.
Give the air feed some thought if you haven't already.
John S. and Pattycakes - still looking for a sibling.
01-29-2002, 12:39 PM
#19
Burning Brakes
Join Date: Aug 2001
Posts: 1,117
Likes: 0
Received 0 Likes
on
0 Posts
Steve,
Sounds like you have a good plan working. If you are looking for larger valves, consider 944 heads. These are one of the big $ 928 tuners' "big secrets", or used to be anyway. The 944 head has significantly larger valves than a 928 head. Bigger than even Euro heads by a significant margin.
You can use the 2V standard, 2V turbo, or (the largest I recall) the 2v "S" (1 year only, so kinda large $ for a used head). The 944 was designed to use the 928 head casting, so fitment is not an issue - you get large valves with all factory parts and very little machine work. There is some minor work to be done, let me know if you need more data.
I'm going 2v with a 5L block, supercharged (not any of the "systems" on the boards) intercooled. Still doing intake math (ugh) - depending on the results of the calculations, custom intake may, or may not, be worth the time on a force-fed motor.
Jim, If you have any dyno numbers on your car, it would be great to know where your car is at currently.
Greg
Sounds like you have a good plan working. If you are looking for larger valves, consider 944 heads. These are one of the big $ 928 tuners' "big secrets", or used to be anyway. The 944 head has significantly larger valves than a 928 head. Bigger than even Euro heads by a significant margin.
You can use the 2V standard, 2V turbo, or (the largest I recall) the 2v "S" (1 year only, so kinda large $ for a used head). The 944 was designed to use the 928 head casting, so fitment is not an issue - you get large valves with all factory parts and very little machine work. There is some minor work to be done, let me know if you need more data.
I'm going 2v with a 5L block, supercharged (not any of the "systems" on the boards) intercooled. Still doing intake math (ugh) - depending on the results of the calculations, custom intake may, or may not, be worth the time on a force-fed motor.
Jim, If you have any dyno numbers on your car, it would be great to know where your car is at currently.
Greg
01-31-2002, 11:35 PM
#20
Three Wheelin'
Thread Starter
Join Date: May 2001
Location: Hudson Valley NY
Posts: 1,641
Likes: 0
Received 0 Likes
on
0 Posts
Update
Jerry Roche (JE piston) said his pistons would work in a nickel-silicon bore with no coating (alusil) to the pistons needed. He suggests a chrome plated or molly ring. Everyone recommends against a spiral lock ring.
I spoke with Jim at Powerhaus. He said all 911 cylinder heads are nickel/silicon and they use molly rings. It seems that nickel/silicon is the way to go. It’s more durable then alusil, which is power honing with silicon.
My 85 euro M28/22 heads has 45 mm (1.773) intake valves. 40 mm (1.576) exhaust valves. 310 hp.
My M28/42 heads has two 37 mm (2 X 1.457 = 2.914) intake valves. Two 33 mm (2 X 1.300 = 2.600) exhaust valves. 316 hp.
The 928’s 32 valve heads flow more air then 16 valve heads on intake and exhaust. The more air/fuel mix you get in and out of a cylinder, the more horsepower it produces. The centrally located plug (32v) burns the air/fuel mixture faster. The two exhaust valves, with their two stems, make the cylinders run cooler. There is less of a tendency for these valves to glow red, and less chance of detonation. With all of this potential for producing high horsepower, the 32v 5.0 liter engine rated at 316 hp has only 6 more horsepower then my euro 16 valve 310 hp engine, why?????
The restriction has to be in the intake ports of the head, the intake manifold or maybe the cams.
John S, I agree we need a cold air intake system for our cars,next project.
Mike thanks for the info.
Greg, good luck on your project. Whose supercharger are you using?
Jim Nowak, I can’t wait to see your dyno numbers.
400hp
The quest continues….
Steve C
The Great White
Jerry Roche (JE piston) said his pistons would work in a nickel-silicon bore with no coating (alusil) to the pistons needed. He suggests a chrome plated or molly ring. Everyone recommends against a spiral lock ring.
I spoke with Jim at Powerhaus. He said all 911 cylinder heads are nickel/silicon and they use molly rings. It seems that nickel/silicon is the way to go. It’s more durable then alusil, which is power honing with silicon.
My 85 euro M28/22 heads has 45 mm (1.773) intake valves. 40 mm (1.576) exhaust valves. 310 hp.
My M28/42 heads has two 37 mm (2 X 1.457 = 2.914) intake valves. Two 33 mm (2 X 1.300 = 2.600) exhaust valves. 316 hp.
The 928’s 32 valve heads flow more air then 16 valve heads on intake and exhaust. The more air/fuel mix you get in and out of a cylinder, the more horsepower it produces. The centrally located plug (32v) burns the air/fuel mixture faster. The two exhaust valves, with their two stems, make the cylinders run cooler. There is less of a tendency for these valves to glow red, and less chance of detonation. With all of this potential for producing high horsepower, the 32v 5.0 liter engine rated at 316 hp has only 6 more horsepower then my euro 16 valve 310 hp engine, why?????
The restriction has to be in the intake ports of the head, the intake manifold or maybe the cams.
John S, I agree we need a cold air intake system for our cars,next project.
Mike thanks for the info.
Greg, good luck on your project. Whose supercharger are you using?
Jim Nowak, I can’t wait to see your dyno numbers.
400hp
The quest continues….
Steve C
The Great White
02-01-2002, 12:54 AM
#21
Steve,
Wow, I had no idea that the J&E pistons could be used in the Alusil bore without coating the pistons. Neither did my Devek engine builder? Hummmmm, what should I do? Or more importantly, what should you do or who do you believe? I would do a little more research before you go by their recommendation. You could be very lucky or?
Yah, I can't wait till the engine is done because it has been 1&1/2 years since we started and whole load of $$$!
Jim Nowak
Wow, I had no idea that the J&E pistons could be used in the Alusil bore without coating the pistons. Neither did my Devek engine builder? Hummmmm, what should I do? Or more importantly, what should you do or who do you believe? I would do a little more research before you go by their recommendation. You could be very lucky or?
Yah, I can't wait till the engine is done because it has been 1&1/2 years since we started and whole load of $$$!
Jim Nowak
02-01-2002, 07:59 AM
#22
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Join Date: May 2001
Location: Hotlanta - NE of the Perimeter
Posts: 12,269
Received 266 Likes
on
153 Posts
Steve-
You are right on the money with the 32v sizes. Something to consider might be the 968 valve sizes - I am researching this info now. The 968 valves are slightly larger than the later year 928's.
Talking with Jim B @ 928 Int'l - he indicates that without radical changes - the 928 can be massaged (normally aspirated) with reilable results up to the Throttle Body limitations, which is ~450 HP.
If you should find any info on the 968 valve sizes - please let me know.
hth and tia-
You are right on the money with the 32v sizes. Something to consider might be the 968 valve sizes - I am researching this info now. The 968 valves are slightly larger than the later year 928's.
Talking with Jim B @ 928 Int'l - he indicates that without radical changes - the 928 can be massaged (normally aspirated) with reilable results up to the Throttle Body limitations, which is ~450 HP.
If you should find any info on the 968 valve sizes - please let me know.
hth and tia-
02-02-2002, 12:57 AM
#23
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Join Date: May 2001
Location: Hotlanta - NE of the Perimeter
Posts: 12,269
Received 266 Likes
on
153 Posts
Update on valve sizes-
Just got back from sneakin' a peak at the 968 SM's -
The exhaust valves for the 928 and the 968 are identical in every dimension.
The 968 Intake valves differ in valve base diameter only - they are 39 mm vs. the 87+ 928 size of 37 mm. All other dimesions are identical.
Now for the interesting part - if the 85/86 is rated for 288 hp (with 35 mm Intake valves) and the 87 S4 is rated for 316 [net = 28hp] (with 37 mm Intake valves) - how much improvement would be made with the 968 Intake valves?
hth-
Just got back from sneakin' a peak at the 968 SM's -
The exhaust valves for the 928 and the 968 are identical in every dimension.
The 968 Intake valves differ in valve base diameter only - they are 39 mm vs. the 87+ 928 size of 37 mm. All other dimesions are identical.
Now for the interesting part - if the 85/86 is rated for 288 hp (with 35 mm Intake valves) and the 87 S4 is rated for 316 [net = 28hp] (with 37 mm Intake valves) - how much improvement would be made with the 968 Intake valves?
hth-
02-02-2002, 01:56 AM
#24
Steve,
You are running dual exhausts, right?
What is the I.D. of the pipes/headers?
Are you thinking of running 21/2" - 3" pipe?
With compression numbers in excess of 10:1 - plus^, under boost, especially, in the mid to upper rpm range that engine is going to have to evacuate a hell of a lot of low volume, high pressure gas.
I'd like to know how that end of the project goes.
Keeping in mind those compression/boost estimates
I can't help but agree with Jim about excercising just a little more caution on the J&E pistons. It would be tragic to shell-out an engine on the professional advise of someone who has, basically ,no stake in a bad outcome -except for flames.
Did you get in touch with Abby on the Louisiana sHARk project? He was SCing too. If nothing else, he or his engine builder might have some info and tips on the piston coating issue.
And you could ask Nicole to consult with her chums across the water. They might have access to the engineering spec/recommendation on pistons.
Drive on.
later
John S. and Pattycakes
You are running dual exhausts, right?
What is the I.D. of the pipes/headers?
Are you thinking of running 21/2" - 3" pipe?
With compression numbers in excess of 10:1 - plus^, under boost, especially, in the mid to upper rpm range that engine is going to have to evacuate a hell of a lot of low volume, high pressure gas.
I'd like to know how that end of the project goes.
Keeping in mind those compression/boost estimates
I can't help but agree with Jim about excercising just a little more caution on the J&E pistons. It would be tragic to shell-out an engine on the professional advise of someone who has, basically ,no stake in a bad outcome -except for flames.
Did you get in touch with Abby on the Louisiana sHARk project? He was SCing too. If nothing else, he or his engine builder might have some info and tips on the piston coating issue.
And you could ask Nicole to consult with her chums across the water. They might have access to the engineering spec/recommendation on pistons.
Drive on.
later
John S. and Pattycakes
02-02-2002, 02:54 AM
#25
John,
Abby used 944 turbo pistons with custom rods and wrist pins. He is going low compression and high boost with his engine.
I'm moving towards high compression and low boost due to already completed engine components (pistons). However, I could easily switch my pistons for the 968 104 mm pistons and achieve low compression and high boost.
I think I will enjoy the normally aspirated engine until I get bored with the performance. Usually boredom sets-in two months after each major engine modification.
Jim Nowak
Abby used 944 turbo pistons with custom rods and wrist pins. He is going low compression and high boost with his engine.
I'm moving towards high compression and low boost due to already completed engine components (pistons). However, I could easily switch my pistons for the 968 104 mm pistons and achieve low compression and high boost.
I think I will enjoy the normally aspirated engine until I get bored with the performance. Usually boredom sets-in two months after each major engine modification.
Jim Nowak
02-03-2002, 12:06 AM
#27
Jay,
My car uses 2-valve heads. I think you could be correct if I were using a 4-valve head, but even if they were to raise compression it wouldn't be much on my engine.
Jim Nowak
My car uses 2-valve heads. I think you could be correct if I were using a 4-valve head, but even if they were to raise compression it wouldn't be much on my engine.
Jim Nowak
02-03-2002, 10:49 AM
#28
Three Wheelin'
Thread Starter
Join Date: May 2001
Location: Hudson Valley NY
Posts: 1,641
Likes: 0
Received 0 Likes
on
0 Posts
Jim and John,
Just to clarify my quote of Jerry Roche, he said, “JE pistons without a coating of any sort to the piston will work in a 928 cylinder bore treated with nickel/ silicon”.
Nickel/silicon is electro plating with nickel matrix and silicon carbide. It is a different process then aluminum/silicone (alucil). For aluminum/silicon the cylinder “bore is machined until the silicon protrude from the aluminum so that the piston and rings only make contact with the silicon” then the bore’s are power honed with a silicon compound completing the process, the end result is a aluminum silicon prep bore.
U.S chrome will do the complete process of nickel/silicon electroplating and cylinder bore machining
Cylinder bore machined to 104 mm is $480/$60 per bore
Electroplating 8 cylinders is $920/$115 per bore
Total is $1400 to prep the block (this price is w/o the cost of pistons)
For any pistons to work in an aluminum/silicon prepared cylinder bore, the pistons have to be chrome plated or iron coated.
I hope this clears up any misunderstanding I may have caused.
Steve C.
The Great White
<a href="http://www.uschrome.com" target="_blank">www.uschrome.com</a>
Just to clarify my quote of Jerry Roche, he said, “JE pistons without a coating of any sort to the piston will work in a 928 cylinder bore treated with nickel/ silicon”.
Nickel/silicon is electro plating with nickel matrix and silicon carbide. It is a different process then aluminum/silicone (alucil). For aluminum/silicon the cylinder “bore is machined until the silicon protrude from the aluminum so that the piston and rings only make contact with the silicon” then the bore’s are power honed with a silicon compound completing the process, the end result is a aluminum silicon prep bore.
U.S chrome will do the complete process of nickel/silicon electroplating and cylinder bore machining
Cylinder bore machined to 104 mm is $480/$60 per bore
Electroplating 8 cylinders is $920/$115 per bore
Total is $1400 to prep the block (this price is w/o the cost of pistons)
For any pistons to work in an aluminum/silicon prepared cylinder bore, the pistons have to be chrome plated or iron coated.
I hope this clears up any misunderstanding I may have caused.
Steve C.
The Great White
<a href="http://www.uschrome.com" target="_blank">www.uschrome.com</a>
02-03-2002, 12:07 PM
#30
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Join Date: May 2001
Location: Hotlanta - NE of the Perimeter
Posts: 12,269
Received 266 Likes
on
153 Posts
I guess the use of the 968 pistons in a 2 valve application will lower the CR.
In the 87 model, stock pistons are 10:1, while in the 968 - 11:1 (note sure of the CR value in the 2 valve motors). One note of significant difference it the stroke value on the 968 vs. the 928 - is this the major factor that causes the CR increase?
In the 87 model, stock pistons are 10:1, while in the 968 - 11:1 (note sure of the CR value in the 2 valve motors). One note of significant difference it the stroke value on the 968 vs. the 928 - is this the major factor that causes the CR increase?