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04-30-2004 | 02:10 PM
#46
Drifting
Joined: Jul 2002
Posts: 3,348
Likes: 0
From: Los Angeles, CA
Originally posted by blau928
Hi There BC..
I beg to differ...!
I think my 928 is VERY reliable.. I have only gotten stuck once in 60k miles of driving. I know that it is a 17yr old car, and it was over 70k new, and maintain it accordingly. After having owned Ferraris, Mercedes, and other Porsche, BMW, and many other cars, the only other car that was as reliable was my S500, with my 740il a close second. I have driven this car to top speed many times, as I have with all my cars.
Now being that this vehicle is speed addictive, most will want to go faster. Thereby placing a higher degree of stress on the engine. Remembering that stresses on an engine are related in a higher proportion to the rotational speed of the components, then fast driving relates DIRECTLY to shorter engine life. Boost alone does NOT..! 100% increase in power from boosting ONLY PLACES 20% more load on the components of the internals. THIS IS NOT THE CASE with higher RPM....
Now, I cannot comment on others' ability to pay for these things, but I can surely say that if you are buying a budget car to go faster, then buy something other than a 928. The 928 is a very complicated automobile. however, in my experience, if maintained PROPERLY, it lasts a long time. mine has over 200k miles, and has never been apart.
I use my car daily, and drive between 150-200miles per day. Like I said, in 60k of driving this car recently, I have only gotten stuck once on the road.. That was from the fuel pump....
You have contradicted yourself by saying <<If we wanted reliability, or cheap repairs, we'd be driving a different sportscar. The 928 is a speed demon. It is a V8. It has a very high top speed. It has torque. It looks muscular. A lot of the owners of these cars like to go fast. Very fast.>>
Now, about spending extra cash on a motor due to experimenting on a boosted motor with 5psi, just plain foolish, when Bill can take the same 5k and upgrade his basic well kept engine with intercoolers etc. and enjoy the car much more by eliminating detonation. FYI, DETONATION is the greatest cause of boosted motor failures. This is from POOR DESIGN....!
However, if Bill is foolish enough to start with a poorly maintained motor, he deserves to pay twice for stupidity or ignorance.. Whether it is Porsche, BMW, Mercedes, Chevy, Ford or any car. Engines are engines...! They all do the same basic things...! The science and technology exists to do supercharging properly at this time. If Bill or whoever does not, then Bill or whomever is asking to grenade his engine.
Hi There BC..
I beg to differ...!
I think my 928 is VERY reliable.. I have only gotten stuck once in 60k miles of driving. I know that it is a 17yr old car, and it was over 70k new, and maintain it accordingly. After having owned Ferraris, Mercedes, and other Porsche, BMW, and many other cars, the only other car that was as reliable was my S500, with my 740il a close second. I have driven this car to top speed many times, as I have with all my cars.
Now being that this vehicle is speed addictive, most will want to go faster. Thereby placing a higher degree of stress on the engine. Remembering that stresses on an engine are related in a higher proportion to the rotational speed of the components, then fast driving relates DIRECTLY to shorter engine life. Boost alone does NOT..! 100% increase in power from boosting ONLY PLACES 20% more load on the components of the internals. THIS IS NOT THE CASE with higher RPM....
Now, I cannot comment on others' ability to pay for these things, but I can surely say that if you are buying a budget car to go faster, then buy something other than a 928. The 928 is a very complicated automobile. however, in my experience, if maintained PROPERLY, it lasts a long time. mine has over 200k miles, and has never been apart.
I use my car daily, and drive between 150-200miles per day. Like I said, in 60k of driving this car recently, I have only gotten stuck once on the road.. That was from the fuel pump....
You have contradicted yourself by saying <<If we wanted reliability, or cheap repairs, we'd be driving a different sportscar. The 928 is a speed demon. It is a V8. It has a very high top speed. It has torque. It looks muscular. A lot of the owners of these cars like to go fast. Very fast.>>
Now, about spending extra cash on a motor due to experimenting on a boosted motor with 5psi, just plain foolish, when Bill can take the same 5k and upgrade his basic well kept engine with intercoolers etc. and enjoy the car much more by eliminating detonation. FYI, DETONATION is the greatest cause of boosted motor failures. This is from POOR DESIGN....!
However, if Bill is foolish enough to start with a poorly maintained motor, he deserves to pay twice for stupidity or ignorance.. Whether it is Porsche, BMW, Mercedes, Chevy, Ford or any car. Engines are engines...! They all do the same basic things...! The science and technology exists to do supercharging properly at this time. If Bill or whoever does not, then Bill or whomever is asking to grenade his engine.
But I also think that most people who get into supercharging, are not as into reliability, as they are into speed. People who are into speed, are willing to do extreme things, like tear their engines apart, of bolt on a supercharger, or turbos. All things that are not in line with proper "factory" maintainance plans. They are going to extremes, to go fast...
I agree that the well-designed kits will probably not significantly reduce engine life.
What I was referring to, was people with "frankenstein" kits.
People are "experimenting" with turbos, superchargers, NOS, etc.
And yes, there is some risk, when you experiment.
Especially when you are talking about something like welding a different throttle body onto your spider, new computer, etc... There is a LOT of risk, and unknowns...
But all I am saying, is that IF he were to blow his 4.5 in the process, it would not be as big of a deal, as blowing up a GTS or GT engine or even an s4. The early engines are in older, less-desirable cars, and you can pick up entire cars, and engines, for under $5,000.
So if we hope for the best, this "experiment" way work out, and he will have a well-tuned, intercooled, low-boost engine, that will last a long time.
But worse case scenario, and he blows it up, he can still replace the engine, and continue with his work, without breaking the bank...
My only point is that early 4.5 engines are cheaper to "experiment" on...
And they are also probably the ones most in need of power enhancements...
04-30-2004 | 05:16 PM
#48
Range Master
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Joined: Apr 2002
Posts: 54,291
Likes: 1,235
Originally posted by bshaw
Yours is an iron bracket? Bolted to the water pump? .
Stock V-drive PS belt, alt belt in stock position, so the crank pulley has been modified from the FAST design also. Interesting...
Yours is an iron bracket? Bolted to the water pump? .
Stock V-drive PS belt, alt belt in stock position, so the crank pulley has been modified from the FAST design also. Interesting...
04-30-2004 | 07:52 PM
#49
Thread Starter
Instructor
Joined: Jan 2004
Posts: 172
Likes: 0
From: Northeast
Mine is about 6.5" diameter and 4 or 5 inches deep, grooved the whole length. SC belt is closest to the engine, alt is next and PS is farthest forward, all ribbed belts. You can just see at the bottom of the first 'bracket' pic I posted. Maybe not a work of art, but then again, not $8k either.
Last edited by bshaw; 04-30-2004 at 10:16 PM.
05-01-2004 | 02:28 AM
#50
Burning Brakes
Joined: Aug 2001
Posts: 1,117
Likes: 0
Originally posted by bshaw
Thanks for the offer on the fuel rails, I'll keep that in mind. You are correct in your statement that the '84 needs bigger injectors to get much past 350 hp. You can increase the fuel pressure to gain more fuel flow, but at some point you just run out of pulse width. Nissan 280ZX Turbo injectors (32 lbs/hour) will fit my '84 with the stock fuel rails, I'm headed that route now if I can verify that they're low Z.
Thanks for the offer on the fuel rails, I'll keep that in mind. You are correct in your statement that the '84 needs bigger injectors to get much past 350 hp. You can increase the fuel pressure to gain more fuel flow, but at some point you just run out of pulse width. Nissan 280ZX Turbo injectors (32 lbs/hour) will fit my '84 with the stock fuel rails, I'm headed that route now if I can verify that they're low Z.
The larger injectors go without saying, I was commenting more to the overall fuel delivery. Also, the later injectors are more available in more outputs, with better atomization than the Type I units. But the T-I units will work fine.
I can get low Z Type I (hose style) injectors if you perchance your quest is unsuccessful. Not sure about the 'Z' of the turbo ZX injectors, if I see one tomorrow, I'll ohm it out for you.
As long as you stay under ~500 RWHP, the rest of the fueling system is adequate, marginal, but adequate. If you want any more HP, the rest of the stuff needs to be upgraded as well - not terribly expensive to do, but has to be done though.
Good Luck,
Greg
05-01-2004 | 10:06 AM
#52
Thread Starter
Instructor
Joined: Jan 2004
Posts: 172
Likes: 0
From: Northeast
Originally posted by gbyron
Bill,
The larger injectors go without saying, I was commenting more to the overall fuel delivery. Also, the later injectors are more available in more outputs, with better atomization than the Type I units. But the T-I units will work fine.
I can get low Z Type I (hose style) injectors if you perchance your quest is unsuccessful. Not sure about the 'Z' of the turbo ZX injectors, if I see one tomorrow, I'll ohm it out for you.
As long as you stay under ~500 RWHP, the rest of the fueling system is adequate, marginal, but adequate. If you want any more HP, the rest of the stuff needs to be upgraded as well - not terribly expensive to do, but has to be done though.
Good Luck,
Greg
Bill,
The larger injectors go without saying, I was commenting more to the overall fuel delivery. Also, the later injectors are more available in more outputs, with better atomization than the Type I units. But the T-I units will work fine.
I can get low Z Type I (hose style) injectors if you perchance your quest is unsuccessful. Not sure about the 'Z' of the turbo ZX injectors, if I see one tomorrow, I'll ohm it out for you.
As long as you stay under ~500 RWHP, the rest of the fueling system is adequate, marginal, but adequate. If you want any more HP, the rest of the stuff needs to be upgraded as well - not terribly expensive to do, but has to be done though.
Good Luck,
Greg
Tell me about your fuel rails...do you have some pics?
05-01-2004 | 02:04 PM
#54
Three Wheelin'
Joined: Mar 2003
Posts: 1,286
Likes: 1
From: New Berlin
Bill, this is informational just in case you decide to build another intercooler in the future.
Your current intercooler design has entry/exit points on the sides connected by long channels.
However, it would be more advantageous to have the entry/exit points on the top and bottom, connected by short channels, while using the same physical dimensions as the current design.
For a good example of what I'm referring to, break out Corkey's book and go to page 117, Fig. 8-21.
Also, go to page 121 Fig. 8-28. Be aware though that there is a typo which reads: '..but the top core has much greater internal flow area,'
It should read: '..but the BOTTOM core has much greater internal flow area,'.
The reason this is true is because the top illustration has approximately 23 channels where the charge can pass through and heat removed, whereas the the bottom illustration has approx 56 channels. Not only that, the 56 channel can flow twice as much charge for any given time since there are twice as many 'doors' to go through.
This typo is born out when it continues to say: 'Furthermore, long tubes have inherently more drag than short tubes.'
While on that page, also refer to Fig. 8-29. It says: 'Always increase the core area by adding a greater number of internal passageways. Do not just make the same number of passages longer.'
I know, details, details! But like it or not, you are in a crash-course to learn all this stuff since you plan on tracking your car.
Your current intercooler design has entry/exit points on the sides connected by long channels.
However, it would be more advantageous to have the entry/exit points on the top and bottom, connected by short channels, while using the same physical dimensions as the current design.
For a good example of what I'm referring to, break out Corkey's book and go to page 117, Fig. 8-21.
Also, go to page 121 Fig. 8-28. Be aware though that there is a typo which reads: '..but the top core has much greater internal flow area,'
It should read: '..but the BOTTOM core has much greater internal flow area,'.
The reason this is true is because the top illustration has approximately 23 channels where the charge can pass through and heat removed, whereas the the bottom illustration has approx 56 channels. Not only that, the 56 channel can flow twice as much charge for any given time since there are twice as many 'doors' to go through.
This typo is born out when it continues to say: 'Furthermore, long tubes have inherently more drag than short tubes.'
While on that page, also refer to Fig. 8-29. It says: 'Always increase the core area by adding a greater number of internal passageways. Do not just make the same number of passages longer.'
I know, details, details! But like it or not, you are in a crash-course to learn all this stuff since you plan on tracking your car.
05-01-2004 | 07:18 PM
#55
Thread Starter
Instructor
Joined: Jan 2004
Posts: 172
Likes: 0
From: Northeast
Yep, good points, Lag. This was designed with a couple of other constraints though, it had to fit in the space given and had to be built with the parts available. Entries on the top and bottom would make REAL tough to fit in a 10" tall space. This was the best compromise available at the time.
BTW, the crash course started years ago, not yesterday :-)
BTW, the crash course started years ago, not yesterday :-)
05-01-2004 | 07:35 PM
#56
Thread Starter
Instructor
Joined: Jan 2004
Posts: 172
Likes: 0
From: Northeast
Originally posted by drnick
bill, did you make this kit yourself and is the air-air intercooler yet to be installed? whats it like to drive? excellent stuff!
bill, did you make this kit yourself and is the air-air intercooler yet to be installed? whats it like to drive? excellent stuff!
And yes, the a-a intercooler is yet to be installed. I still have some loose ends to tie up, some tuning to do (I haven't touched the cold fueling yet, and part throttle transitions still need work) BOV, WBO2, then install the intercooler and put the smaller pulley on the Vortech :-)
05-02-2004 | 02:00 AM
#57
Burning Brakes
Joined: Aug 2001
Posts: 1,117
Likes: 0
Bill,
2 for 2 on the TurboZX injectors being high Z, though I have not verified this firsthand, so I still would not swear to it.
The rails are aluminum extrusion(6061-T6), with properly detailed holes for rach injector. Each end is drilled and tapped for an 8AN o-ring style end port. Allows you to use either a 8AN or 6AN male o-ring fitting on the rail inlet/outlets.
This is not the pipe thread (NPT) style that some "tuners" (scarily enough, on Porsches) use. NPT can crack the tube and/or require a sealing compound of some sort - neither of which is desirable with a 40+ PSI gasoline sprayer under the hood.
The rails are drilled to line up with the stock intake holes, with a stanchion on each end to hold them down - same holes as the bung retainers. One can simply plug-in the newer style injectors with this setup - the Bosch injector electrical plugs are the same. The only difference is the newer style injectors will be about 4mm shorter 'reach' into the intake - really not a problem, since the pattern doesn't spread fast enough to hit the side of the hole in the intake. But, if you're feeling retentive, you can mill another 4mm down into each of the injector bosses in each intake runner. A 4-flute end mill should produce a decent result, just kind of a PITA to do the set-up.
I'll post a link to a shot of the rails in a little while - res won't be great (camphone) but you can at least get an idea. The stanchions in the pic are not drilled yet. I left layout blue on one so you can better see the contast for the injector details.
They're not on my car yet (84US), doing some things all at once, don't have time to do and redo. I'll have lotsa pics on my web site once its finished.
Greg
2 for 2 on the TurboZX injectors being high Z, though I have not verified this firsthand, so I still would not swear to it.
The rails are aluminum extrusion(6061-T6), with properly detailed holes for rach injector. Each end is drilled and tapped for an 8AN o-ring style end port. Allows you to use either a 8AN or 6AN male o-ring fitting on the rail inlet/outlets.
This is not the pipe thread (NPT) style that some "tuners" (scarily enough, on Porsches) use. NPT can crack the tube and/or require a sealing compound of some sort - neither of which is desirable with a 40+ PSI gasoline sprayer under the hood.
The rails are drilled to line up with the stock intake holes, with a stanchion on each end to hold them down - same holes as the bung retainers. One can simply plug-in the newer style injectors with this setup - the Bosch injector electrical plugs are the same. The only difference is the newer style injectors will be about 4mm shorter 'reach' into the intake - really not a problem, since the pattern doesn't spread fast enough to hit the side of the hole in the intake. But, if you're feeling retentive, you can mill another 4mm down into each of the injector bosses in each intake runner. A 4-flute end mill should produce a decent result, just kind of a PITA to do the set-up.
I'll post a link to a shot of the rails in a little while - res won't be great (camphone) but you can at least get an idea. The stanchions in the pic are not drilled yet. I left layout blue on one so you can better see the contast for the injector details.
They're not on my car yet (84US), doing some things all at once, don't have time to do and redo. I'll have lotsa pics on my web site once its finished.
Greg
05-02-2004 | 02:31 AM
#58
Burning Brakes
Joined: Aug 2001
Posts: 1,117
Likes: 0
Here they are in less than glorious resolution...
http://pictures.sprintpcs.com/?sivt=...Jo8k8FoaFoUoGh
http://pictures.sprintpcs.com/?sivt=...JJ8h8HQ7MhLhjU
Greg
http://pictures.sprintpcs.com/?sivt=...Jo8k8FoaFoUoGh
http://pictures.sprintpcs.com/?sivt=...JJ8h8HQ7MhLhjU
Greg
05-02-2004 | 01:27 PM
#60
Burning Brakes
Joined: Aug 2001
Posts: 1,117
Likes: 0
I can tell you it will be considerably less for 2 rails and connectors than the 951 folks (that I've checked) charge for 1 rail. They'll also be less than if you spent the time to do all the measurements and ordered them as a one-off. Still figuring out how many of these I'm going to make per batch, so my price is kinda in flux right now - I did a run of 8 for proto purposes and still have a couple pair left.
The more basic parts I buy, the lower my cost, but I don't want to take funding away from other inventory items...
You get the picture. If you are in need, I do have 2 pair left. PM me, I can give you a price - don't want to be doing a lot of 'selling' on the board, until I send my Renn sponsorship check in.
Greg
The more basic parts I buy, the lower my cost, but I don't want to take funding away from other inventory items...
You get the picture. If you are in need, I do have 2 pair left. PM me, I can give you a price - don't want to be doing a lot of 'selling' on the board, until I send my Renn sponsorship check in.
Greg