S4 Twin Turbo will be a reality!
11-23-2005, 04:34 PM
#61
Captain Obvious
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Originally Posted by bcdavis
Yes, but 928 Turbosports is already marketing a low-budget turbo kit for the 928.
So knowing John does good work, I would rather see him prove his point to the rest of the 928 community, about how fast a turbo 928 can be, rather than put out another product like Goldmember, that no one respected, because it's dyno numbers were so low compared to the supercharged s4s. If he does a cheap and mild turbo setup on that s4, it's going to be right in the same ballpark as the supercharged cars, and in the same ballpark as the 928 Turbosports kit. But expensive as hell. If a turbo kit is going to be expensive (which it is), then it ought to be putting out 500+ RWHP like the MURPH cars...
So knowing John does good work, I would rather see him prove his point to the rest of the 928 community, about how fast a turbo 928 can be, rather than put out another product like Goldmember, that no one respected, because it's dyno numbers were so low compared to the supercharged s4s. If he does a cheap and mild turbo setup on that s4, it's going to be right in the same ballpark as the supercharged cars, and in the same ballpark as the 928 Turbosports kit. But expensive as hell. If a turbo kit is going to be expensive (which it is), then it ought to be putting out 500+ RWHP like the MURPH cars...
I believe that even a mildly TTed S4 would be much faster than the rear turbo or majority of the SCed 928s and this would include my car too.
Also, I am proud of the fact that my low budget SC runs as good as the high $$$$$ SC kits. This winter the intercooler is going in with a slightly smaller SC pulley (8psi). With traction, I should be able to run 12.4-12.5sec all day long. My goal is to produce 400RWHP for under $1500, once I reach this I’ll stop. As you can see, some people's goal is to go all out, mine is much less.
11-23-2005, 05:00 PM
#62
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I just think that since John quoted around $8,000-$13,000 for his OB manifolds, etc,
I can't imagine his turbo kit being cheap. I really think that the only way people
are going to drop $10,000+ into a turbo kit, is if it delivers bigger dyno numbers
than the MURPH guys, with more time under the power curve... People will
only pay that kind of money to have the fastest 928 on the block. If he
does a "cheap" kit, and it only produces 400RWHP, people who want
power, will just get a supercharger and get the same numbers for
a lot less $$$. And if they want a cheap turbo kit, they can get
the 928Turbosports starter kit, or a rear turbo setup.
I can't imagine his turbo kit being cheap. I really think that the only way people
are going to drop $10,000+ into a turbo kit, is if it delivers bigger dyno numbers
than the MURPH guys, with more time under the power curve... People will
only pay that kind of money to have the fastest 928 on the block. If he
does a "cheap" kit, and it only produces 400RWHP, people who want
power, will just get a supercharger and get the same numbers for
a lot less $$$. And if they want a cheap turbo kit, they can get
the 928Turbosports starter kit, or a rear turbo setup.
11-23-2005, 06:44 PM
#63
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Why will it be so difficult to best the Vortech stuff out there? Each turbo I have will not even be working hard to blow out 275-300 HP each. Even if the car makes the same HP on the dyno, the torque numbers will be much higher and this means a wider powerband and ultimately a more power"full" car. Like I said I'm not going to go cheap. I'd rather build the best and rest on that, compared to building something the masses want to bolt on. If you want cheap, go and get a Mustang, the short blocks are like $2,500 already prepped. Not saying there is anything wrong with them, but cheap and Porsche usually just means cheap...catch my drift? Remember, a power curve that linearly increases to a peak of 400 HP won't match a power curve that makes, say 390 HP with 75-100 more ft-lbs across the RPM band. Afterall, your tach has to make it to the redline by passing through the entire speed range, right? You simply can't drive it at the redline, remember that.
Remember, I showed that my 4.5 liter twin was quicker than an equally CS boosted 4.5 liter car and he had the advantage of the 5-speed. Goldmember mowed down a 1/4 mile at 13.6...I want to say the car did 16 seconds when I started. You always have to look at % improvement. Guys on this board like to make comparisons...but it is apples to oranges up to now. They may have made the most powerful apple top date, but I haven't touched my apple yet...I'm still working on the citrus fruit family right now. 12.9 sec on a car that did 14 to 14.2 seconds out of the crate isn't as big an improvement as 13.6 on a car that did 16 stock. That was with quite small K-24 units. 0-60 was a brisk 5.2 seconds, stock is 8.0 seconds. Remember, these are 3-spd A/T car figures. Show me any 4.5 liter 928 powered 928 3-spd AT that bests these figures. You would need a 5.7 liter Chevy to better those numbers. The car would have made a lot more power with larger turbos. When it was dynoed it put down 355 ft-lbs and about 265-270 HP (the exact number escapes me right now) to the wheels through the 3-spd turdbox. That was on a 100F day. The power curve was basically flat from 3600 on out. Peak numbers are meaningless unless you look at the whole powerband width. I would have preferred more peak HP, but the 100F tems cost me at least 30-40 HP. I believe my original estimate of 375 HP at the crank to be valid...assuming it isn't a sauna box outside.
There is lots of potential with the 32V engine for sure...lower duration minimal overlap camshafts, nice combustion chamber, etc.
Remember, I showed that my 4.5 liter twin was quicker than an equally CS boosted 4.5 liter car and he had the advantage of the 5-speed. Goldmember mowed down a 1/4 mile at 13.6...I want to say the car did 16 seconds when I started. You always have to look at % improvement. Guys on this board like to make comparisons...but it is apples to oranges up to now. They may have made the most powerful apple top date, but I haven't touched my apple yet...I'm still working on the citrus fruit family right now. 12.9 sec on a car that did 14 to 14.2 seconds out of the crate isn't as big an improvement as 13.6 on a car that did 16 stock. That was with quite small K-24 units. 0-60 was a brisk 5.2 seconds, stock is 8.0 seconds. Remember, these are 3-spd A/T car figures. Show me any 4.5 liter 928 powered 928 3-spd AT that bests these figures. You would need a 5.7 liter Chevy to better those numbers. The car would have made a lot more power with larger turbos. When it was dynoed it put down 355 ft-lbs and about 265-270 HP (the exact number escapes me right now) to the wheels through the 3-spd turdbox. That was on a 100F day. The power curve was basically flat from 3600 on out. Peak numbers are meaningless unless you look at the whole powerband width. I would have preferred more peak HP, but the 100F tems cost me at least 30-40 HP. I believe my original estimate of 375 HP at the crank to be valid...assuming it isn't a sauna box outside.
There is lots of potential with the 32V engine for sure...lower duration minimal overlap camshafts, nice combustion chamber, etc.
11-23-2005, 07:05 PM
#64
Man of many SIGs
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Kuhn, I applaud you. 
You are forging a new path and aren't easily pulled into petty arguments. At least lately. And there have been plenty of opportunities for them. Keep up the hard work. I am sure it will pay off in the end. 
By the way. Are you really wanting to get 8-13k for manifolds? Wow. Way outta my league. But still, good luck.
Quote" I haven't touched my apple yet...I'm still working on the citrus fruit family right now."
11-23-2005, 07:43 PM
#65
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Fabio...not sure where the 13K came from...I was originally estimating about $9,000 for the entire system, including all of the goods...
Now I'm off to venture into the 4.5 liter navel orange once again.
Now I'm off to venture into the 4.5 liter navel orange once again.
11-23-2005, 08:05 PM
#66
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I think people would pay that much, if it had better preformance numbers than the supercharger kits. Dyno aside, top numbers aside. That's been discussed to death. But if you could prove your turbo s4 could beat the supercharged cars in a race, I think you'd have some buyers...
11-24-2005, 07:56 AM
#67
Drifting
one other factor that may put people off the turbo route on the older cars is the fact that john saw fit to rebuild the engine using custom pistons and nikasil coatings. bang for the buck, bolting on a supercharger is much easier.
11-24-2005, 11:42 AM
#68
Race Director
the next couple of years will be very good to 928ers....already have proven S/C kits and turbos are on the way! Three years from now a stock S4 will have at least 5 options to 400rwhp...stroker (+monster 7.4L)...twinscrew...vortech....TT (John)...or TT (turbosports)....5 years ago there wasn't very many options....just the stroker and vortech!
Times are good for 928's
Times are good for 928's
11-24-2005, 11:53 AM
#69
Captain Obvious
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Originally Posted by IcemanG17
the next couple of years will be very good to 928ers....already have proven S/C kits and turbos are on the way! Three years from now a stock S4 will have at least 5 options to 400rwhp...stroker (+monster 7.4L)...twinscrew...vortech....TT (John)...or TT (turbosports)....5 years ago there wasn't very many options....just the stroker and vortech!
Times are good for 928's
Times are good for 928's
Ona side note, I remember back in ’98 when I bought my first 928 (’83), most of the owners took their 928s in for service. Any high performance modifications were looked at as a “no - no” and hardly anyone did their own work. Anyone that did their own wrenching was usually treated as a grease monkey or a cheapo. Over the years this shifted to most of us becoming DIY owners. As soon as this happened, a lot of the neat aftermarket parts started to surface. The Boxter board sort of reminds me of those days.
11-24-2005, 10:01 PM
#70
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We all should be proud to be working on our own kit here. I'm glad that there is a rather large number of people doing serious modifications to these cars. We aren't modifying hondas here.
We're extending the life of some awesomely engineered Porsche machinery using the last 20 years of R&D that the world has done. Not applying what has been learned would be a crime. Really, how many cars out there have the potential of the 928, or even the stock performance?
Anyone can build a bomb to run in a straight line for 11.5sec. It takes some serious work to build a supercar that will do it time after time and turn corners as well. Big Kudo's to those that have taken the plunge, I hope to as well at some point. Right now I'm mid-914 and 928, big power for my 914 and awesome devek suspension upgrades for my 928. Eventually I'll do some motor work to my 928, and I can't wait to have to put together the choices.
Thanks herr-Kuhn, 928 turbosports, 928 Specialists, FAST 928, devek, 928 international and all the rest I forgot for giving me so many options for an old, out of date, poorly marketed, limited build car.
I WILL STOMP MY BOSS'S SKYLINE SOME TIME DAY - EVEN IN A STRAIGHT LINE.
We're extending the life of some awesomely engineered Porsche machinery using the last 20 years of R&D that the world has done. Not applying what has been learned would be a crime. Really, how many cars out there have the potential of the 928, or even the stock performance?
Anyone can build a bomb to run in a straight line for 11.5sec. It takes some serious work to build a supercar that will do it time after time and turn corners as well. Big Kudo's to those that have taken the plunge, I hope to as well at some point. Right now I'm mid-914 and 928, big power for my 914 and awesome devek suspension upgrades for my 928. Eventually I'll do some motor work to my 928, and I can't wait to have to put together the choices.
Thanks herr-Kuhn, 928 turbosports, 928 Specialists, FAST 928, devek, 928 international and all the rest I forgot for giving me so many options for an old, out of date, poorly marketed, limited build car.
I WILL STOMP MY BOSS'S SKYLINE SOME TIME DAY - EVEN IN A STRAIGHT LINE.
11-25-2005, 01:53 PM
#71
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The easy route is rarely the best route...just remember that. In my opinion, if something is worth doing it is worth doing all the way. It would be easy for me to eat at McDonalds every day, but I prefer to cook my own food. I guess you see my point here.
Forged pistons would be a smart move on any forced induced car. It was my preference, not a necessity, but a preference. You see, with them I don't have to worry about smacking off a ring land if something like a bad tank of gas comes along. Take a look at the high temps strength of a 2618 alloy compared to the Mahle alloy on the stock cast pistons...you just might decide to do the same thing I have done. There is a technical reason cars like the 944 turbo and Ford GT come with forged internals from the manufacturer.
Quicker and cheaper won't seem like the right chioce when you can't get by the better machine, be it a Porsche, Audi, Honda or Subaru example...the fundamentals still apply and that is that the turbo holds the most potential for increasing the overall performance of the car. Everybody sees superchargers on drag cars for one reason...turbos have been kept out by the rule makers because they offer so much more potential.
So the turbo may cost 30% more and have 1.5X-2.0X the install time...in the grand scheme of things if the performance is better then the additional is clearly worth the difference...at least in my mind.
Of course, the value is always in the eye of the purchaser.
Forged pistons would be a smart move on any forced induced car. It was my preference, not a necessity, but a preference. You see, with them I don't have to worry about smacking off a ring land if something like a bad tank of gas comes along. Take a look at the high temps strength of a 2618 alloy compared to the Mahle alloy on the stock cast pistons...you just might decide to do the same thing I have done. There is a technical reason cars like the 944 turbo and Ford GT come with forged internals from the manufacturer.
Quicker and cheaper won't seem like the right chioce when you can't get by the better machine, be it a Porsche, Audi, Honda or Subaru example...the fundamentals still apply and that is that the turbo holds the most potential for increasing the overall performance of the car. Everybody sees superchargers on drag cars for one reason...turbos have been kept out by the rule makers because they offer so much more potential.
So the turbo may cost 30% more and have 1.5X-2.0X the install time...in the grand scheme of things if the performance is better then the additional is clearly worth the difference...at least in my mind.
Of course, the value is always in the eye of the purchaser.
