Supercharged S3
01-15-2003, 04:16 PM
#61
Drifting
Welcome to the V8 crowd. I think what you are reading is slightly askew. There are many 928's out there running 290/300 Rear Wheel Horse Power (RHWP) which equates to an easy 350/360 flywheel hp. These 928's are basically fine tuned stockers. I know of people running 330/350 rwhp without strokers and superchargers which is over 400 flywheel hp without opening up the engine.
It's not as easy building an engine which only 60,000 were ever made in all different configurations. The people usually associated with building 928's are quality consious and really don't want to destroy another rare engine for testing. You can scatter a SBC and walk around the corner and get a dozen more. Have a custom set of SBC heads made from scratch and then compare the price to 928 parts. Then again, have you ever seen a SBC run 450 rwhp for over 100k miles with no degradation of performance? DEVEK has proven it's achievable. Granted it's not cheap, but I think that a SBC that could do that wouldn't be a couple of thousand dollars. (I haven't seen one yet!)
Dave
(KETCHMI)
It's not as easy building an engine which only 60,000 were ever made in all different configurations. The people usually associated with building 928's are quality consious and really don't want to destroy another rare engine for testing. You can scatter a SBC and walk around the corner and get a dozen more. Have a custom set of SBC heads made from scratch and then compare the price to 928 parts. Then again, have you ever seen a SBC run 450 rwhp for over 100k miles with no degradation of performance? DEVEK has proven it's achievable. Granted it's not cheap, but I think that a SBC that could do that wouldn't be a couple of thousand dollars. (I haven't seen one yet!)
Dave
(KETCHMI)
01-15-2003, 05:47 PM
#64
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Dave I think the point that Richard was trying to make is that a Z06 vette comes stock with 420 (conservative) fhp from 350 ci. Taking that to 520 will not shorten the life span of that motor any mire than it will on thee 928. It will however cost phenomenally less. Example: for $400 you can buy a killer cam for a sbc. Since the 928 has 4 cams does it cost 4 times as much? No it's six times as much and very little info on results. In fact a lot of people say you cant do anything to speak of with the 928 cams. Although I dont have ANY personal experience with this, the 944 guys change cams without thinking twice. Same head right? Bottom line: I can take almost ANY american V8, change cam, exhaust, throttle body and chip and have serious performance. Why does it take a 6 to 10 thousand dollar blower or a stroker motor to pick up some power on a 928?
01-15-2003, 06:12 PM
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Thanks carlos-- that's exactly what I was trying to say!
Both the sbc and porsche v-8's operate on the same basic principles. Why is it so hard to upgrade? Is it the lack of DOCUMENTED power increases?. I know some companies supply dyno sheets (as they should) but there is still a lack of basic info on stuff like flow numbers for the heads, porting info, and ignition upgrades. It seems like a few hardcore porsche fans come up with some upgrades (good job Iceshark!!) but they move heaven and earth to accomplish this. As far as I know there's nothing mystical about these engines. I know blasphemy!
Both the sbc and porsche v-8's operate on the same basic principles. Why is it so hard to upgrade? Is it the lack of DOCUMENTED power increases?. I know some companies supply dyno sheets (as they should) but there is still a lack of basic info on stuff like flow numbers for the heads, porting info, and ignition upgrades. It seems like a few hardcore porsche fans come up with some upgrades (good job Iceshark!!) but they move heaven and earth to accomplish this. As far as I know there's nothing mystical about these engines. I know blasphemy!
01-15-2003, 08:45 PM
#66
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva"> Why does it take a 6 to 10 thousand dollar blower or a stroker motor to pick up some power on a 928?
</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">First, you really must compare similar motors. Really the only motor that is close to the 928 motor is the ZR-1 motor. However, for arguments sake lets take the new aluminum LT-1 motor and add some performance goodies.
I'm choosing to showcase Lingenfelter because he makes a good high quality product similar to the products we would consider adding to our 928s. Lingenfelter wants $4,950.00 for his supercharger kit, parts only, and another $750.00 for an unpainted hood so your kit can fit or for $8,399 installed. His kit will get you another 100 flywheel horsepower. To get to the 140 extra hp you will need to look at the fine print and add some components: **LS1 490 HP figure includes: headers, cat back exhaust and air intake. See pricing below. A few extras on top of the installed/uninstalled price to complete the kit:
LPE high flow air intake system $300.00
LPE lighted boost gauge $295.00
Lpe 1 3/4" stainless long tube headers $1,395.00
Corsa stainless steel exhaust system $795.00
HD automatic transmission rebuild $2,595.00
Yank custom torque converter* $600.00
Labor to R&R transmission $350.00
Polished supercharger $1,000.00
To get to 550 horsepower, twin-turbo, you will need to ante up a bit: Manual transmission package $22,995.00
Automatic transmission upgrade $2,595.00
650 horsepower TT will run a bit more:
Manual transmission $ 39,995.00
Automatic transmission upgrade $2,595.00
725 TT a little higher:
Manual transmission $49,995.00
Automatic transmission upgrade $2,595.00
Let's look at their naturally aspirated motors. A 427 with 500 horsepower will cost you:
Corvette LS1 $28,500.00
Corvette ZO6 $26,500.00
HD Automatic transmission rebuild $2,595.00
O.K., so the 427 is a little too expensive and you only want 475 horsepower. Let's buy the 383 motor:
Manual transmission $16,995.00
Automatic transmission upgrade $2,195.00
Ouch, a Corvette isn't cheap either. You really must look at similar engines if you want to talk about performance. Sure, you can upgrade that iron block Chevy fairly cheap but let's compare apples to apples.
</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">First, you really must compare similar motors. Really the only motor that is close to the 928 motor is the ZR-1 motor. However, for arguments sake lets take the new aluminum LT-1 motor and add some performance goodies.
I'm choosing to showcase Lingenfelter because he makes a good high quality product similar to the products we would consider adding to our 928s. Lingenfelter wants $4,950.00 for his supercharger kit, parts only, and another $750.00 for an unpainted hood so your kit can fit or for $8,399 installed. His kit will get you another 100 flywheel horsepower. To get to the 140 extra hp you will need to look at the fine print and add some components: **LS1 490 HP figure includes: headers, cat back exhaust and air intake. See pricing below. A few extras on top of the installed/uninstalled price to complete the kit:
LPE high flow air intake system $300.00
LPE lighted boost gauge $295.00
Lpe 1 3/4" stainless long tube headers $1,395.00
Corsa stainless steel exhaust system $795.00
HD automatic transmission rebuild $2,595.00
Yank custom torque converter* $600.00
Labor to R&R transmission $350.00
Polished supercharger $1,000.00
To get to 550 horsepower, twin-turbo, you will need to ante up a bit: Manual transmission package $22,995.00
Automatic transmission upgrade $2,595.00
650 horsepower TT will run a bit more:
Manual transmission $ 39,995.00
Automatic transmission upgrade $2,595.00
725 TT a little higher:
Manual transmission $49,995.00
Automatic transmission upgrade $2,595.00
Let's look at their naturally aspirated motors. A 427 with 500 horsepower will cost you:
Corvette LS1 $28,500.00
Corvette ZO6 $26,500.00
HD Automatic transmission rebuild $2,595.00
O.K., so the 427 is a little too expensive and you only want 475 horsepower. Let's buy the 383 motor:
Manual transmission $16,995.00
Automatic transmission upgrade $2,195.00
Ouch, a Corvette isn't cheap either. You really must look at similar engines if you want to talk about performance. Sure, you can upgrade that iron block Chevy fairly cheap but let's compare apples to apples.
01-15-2003, 08:54 PM
#67
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JIM NOWAK: You are dead on with that post it cost money any direction you go looking for hp. The problem I have is the 928 motor doesn't have the r&d that it takes to really see what it can do for the average guy over the long haul. I feel that if you what to play you gotta pay. I would try the stroker with a supercharger.
Curious George
Curious George
01-15-2003, 09:40 PM
#68
George,
Your right! The problem with 928 development is the damn all aluminum engine. The Alusil bore makes the engine difficult to develop. Any piston manufacturer can make pistons that will work in an iron bore but tell them you have an aluminum bore and watch them either run away or charge 10x the price they would charge to make a piston for a Chevy engine. Of course, Porsche and their suppliers knows what to do and how to do it but you don't see them sharing any of their knowledge. No doubt, Porsche could make the 928 motor have a reliable 700 horsepower but they are concerned with selling new cars not selling products to make their old cars as fast or faster than their new products. Why would you buy a new $100,000+ 911 twin turbo if you could buy a twin-turbo kit from Porsche for $20,000 and installl it on the 928 and have a car that would absolutely kill the 911 in performance. There is no replacement for displacement!
Anyway, I think the key would be to ditch the aluminum bore if you want to pressurize the 928 engine. Once you get rid of the aluminum bore, just about anyone can make these cars fast. You will not have to worry as much about the engine grenading under boost either. The Alusil bore is great for what it was intended to do but if I had all my money back from my engine mods. I would have the 928 motor sleeved, fire ringed, and add some serious boost. If you don't want the motor sleeved, I'd just get a supercharger and a good intercooler and let her rip. If it blows, a good used 928 replacement motor can be had for $1,000 to $3,000 if you look in the right places.
Your right! The problem with 928 development is the damn all aluminum engine. The Alusil bore makes the engine difficult to develop. Any piston manufacturer can make pistons that will work in an iron bore but tell them you have an aluminum bore and watch them either run away or charge 10x the price they would charge to make a piston for a Chevy engine. Of course, Porsche and their suppliers knows what to do and how to do it but you don't see them sharing any of their knowledge. No doubt, Porsche could make the 928 motor have a reliable 700 horsepower but they are concerned with selling new cars not selling products to make their old cars as fast or faster than their new products. Why would you buy a new $100,000+ 911 twin turbo if you could buy a twin-turbo kit from Porsche for $20,000 and installl it on the 928 and have a car that would absolutely kill the 911 in performance. There is no replacement for displacement!
Anyway, I think the key would be to ditch the aluminum bore if you want to pressurize the 928 engine. Once you get rid of the aluminum bore, just about anyone can make these cars fast. You will not have to worry as much about the engine grenading under boost either. The Alusil bore is great for what it was intended to do but if I had all my money back from my engine mods. I would have the 928 motor sleeved, fire ringed, and add some serious boost. If you don't want the motor sleeved, I'd just get a supercharger and a good intercooler and let her rip. If it blows, a good used 928 replacement motor can be had for $1,000 to $3,000 if you look in the right places.
01-15-2003, 10:08 PM
#69
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Jim,
I haven't seen you on the board in a while, welcome back. There is a post somewhere by Z that that describes the combustion chambers and cylinders of the S4 to be effective in preventing detonation. I believe it is in the "Supercharged S4" post. He named several factors: hemispherical piston and head shapes, valve spacing, valve angles and that they being all aluminum disipate heat quickly. This is further evidenced by the fact that the <a href="http://porsche-cars.com/history944a.htm" target="_blank">944 4 alve, 928 S4 and 959 have the same combustion chamber, valves, and angles.</a> The 959 has a 8.3:1 compression ratio though.
By the way I have picked a M112 to use in my project.
Andy K
I haven't seen you on the board in a while, welcome back. There is a post somewhere by Z that that describes the combustion chambers and cylinders of the S4 to be effective in preventing detonation. I believe it is in the "Supercharged S4" post. He named several factors: hemispherical piston and head shapes, valve spacing, valve angles and that they being all aluminum disipate heat quickly. This is further evidenced by the fact that the <a href="http://porsche-cars.com/history944a.htm" target="_blank">944 4 alve, 928 S4 and 959 have the same combustion chamber, valves, and angles.</a> The 959 has a 8.3:1 compression ratio though.
By the way I have picked a M112 to use in my project.
Andy K
01-15-2003, 10:14 PM
#70
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Question...
What are the negatives regarding potential damage that can be done or take place over the long haul to a 928 engine by being supercharged vs one that is not. I'm speaking of a "properly built and installed" SC system.
Tim Delarm
What are the negatives regarding potential damage that can be done or take place over the long haul to a 928 engine by being supercharged vs one that is not. I'm speaking of a "properly built and installed" SC system.
Tim Delarm
01-15-2003, 11:56 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by GoRideSno:
<strong>There is a post somewhere by Z that that describes the combustion chambers and cylinders of the S4 to be effective in preventing detonation. I believe it is in the "Supercharged S4" post. He named several factors: hemispherical piston and head shapes, valve spacing, valve angles and that they being all aluminum disipate heat quickly</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Remember the analogy of the ripples from dropping a rock into the center of a bowl of water?
<img src="http://www.momentoffame.com/snapshots/MomentOfFame/l28263.jpg" alt=" - " />
<strong>There is a post somewhere by Z that that describes the combustion chambers and cylinders of the S4 to be effective in preventing detonation. I believe it is in the "Supercharged S4" post. He named several factors: hemispherical piston and head shapes, valve spacing, valve angles and that they being all aluminum disipate heat quickly</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Remember the analogy of the ripples from dropping a rock into the center of a bowl of water?
<img src="http://www.momentoffame.com/snapshots/MomentOfFame/l28263.jpg" alt=" - " />
01-16-2003, 03:01 PM
#74
Carlos,
I think I could have a bracket and tensioner made for less than $300 and the pulley would run another $50 to 300 depending on how you made the pulley. Plumbing would probably be another $100 to $300. Of course, I'm talking in theory on the 928 but from experience on my Mercedes. I, hopefully, will get my car back in the next couple of days and I can eliminate the theory aspect. I just do not have my car to make the measurements nor have I had it for the last two and a half years......another story another time.
I don't think there is any reason you couldn't do a complete custom kit, depending on local machinist talent and cost, for less than $3500 with everything you need to get some serious horsepower. Many people are awfully proud of their R&D work. Supercharging is not rocket science and they have been doing it to engines for over 60 years.
I'm using Foy Gilmore to make my custom car parts. You may or may not know of him but he is really big in making custom chassis for drag racers and got his start by making custom headers. He does great work and is reasonably priced and is currently making custom headers for my Mercedes. In fact, some Hospitals use him for precision machining surgical equipment. The problem is he is so popular he is booked for the next decade.
I think I could have a bracket and tensioner made for less than $300 and the pulley would run another $50 to 300 depending on how you made the pulley. Plumbing would probably be another $100 to $300. Of course, I'm talking in theory on the 928 but from experience on my Mercedes. I, hopefully, will get my car back in the next couple of days and I can eliminate the theory aspect. I just do not have my car to make the measurements nor have I had it for the last two and a half years......another story another time.
I don't think there is any reason you couldn't do a complete custom kit, depending on local machinist talent and cost, for less than $3500 with everything you need to get some serious horsepower. Many people are awfully proud of their R&D work. Supercharging is not rocket science and they have been doing it to engines for over 60 years.
I'm using Foy Gilmore to make my custom car parts. You may or may not know of him but he is really big in making custom chassis for drag racers and got his start by making custom headers. He does great work and is reasonably priced and is currently making custom headers for my Mercedes. In fact, some Hospitals use him for precision machining surgical equipment. The problem is he is so popular he is booked for the next decade.
01-16-2003, 04:28 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Jim Nowak:
<strong>Supercharging is not rocket science and they have been doing it to engines for over 60 years.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Actually they've been supercharging engines since the late 1800's already. Even centrifugal superchargers have been around and been used since before World War One. This isn't exactly the cutting edge, high tech, never been done before stuff that some people apparently think it is.
<strong>Supercharging is not rocket science and they have been doing it to engines for over 60 years.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Actually they've been supercharging engines since the late 1800's already. Even centrifugal superchargers have been around and been used since before World War One. This isn't exactly the cutting edge, high tech, never been done before stuff that some people apparently think it is.