Boost + 928... someone talk to me
#16
Race Director
can boost produce more hp from a 928 engine...for sure......
is it cheaper than rebuilding the engine or changing internal parts....yes
it all depends on what you want to do.....street car or race car.....how often will it be driven to the limit....and for how long (think Open Road Racing)....
Most boosted 928's are supercharged and street cars.....so they get short bursts of VERY high power....then go back to normal driving.....boost is great at this...
IF you want extended time at high load-RPM then there are large issues to overcome with supercharging...& turbos to a slightly less extent..... The most reliable high HP 928's are all strokers (increased displacement)....for a very good reason.....
is it cheaper than rebuilding the engine or changing internal parts....yes
it all depends on what you want to do.....street car or race car.....how often will it be driven to the limit....and for how long (think Open Road Racing)....
Most boosted 928's are supercharged and street cars.....so they get short bursts of VERY high power....then go back to normal driving.....boost is great at this...
IF you want extended time at high load-RPM then there are large issues to overcome with supercharging...& turbos to a slightly less extent..... The most reliable high HP 928's are all strokers (increased displacement)....for a very good reason.....
#18
Three Wheelin'
With regards to turbo setups, what about that Finnish guy that put his turbo right before his radiator and a bunch of convoluted plumbing to an intercooler? Never seen that offered by anyone so i figure he did it/engineered it all himself. He's on Rennlist. I think he said he used a Volvo truck turbo. Seems pretty badass to me.
#19
Captain Obvious
Super User
Super User
The Scandinavian's are a class on their own. I've see some many awesome, one off creations, come out of that peninsula that it truly is amazing. This is one of them. The turbo is after the radiator by the way.
#20
Rennlist Member
This
This is what can happen when people have a different view on life, and have waaaay too many holidays.....
#21
Drifting
I did carls raptor sc first , had 7 psi but didnt come on till around 3000 rpm and missed low end torque . If i went the the kuhn twin turbo first ( boost comes on earlier and with much torque) I never would have done the stroker.....
sc stage 3 7500
carls stage 2 6000
kuhn twin turbo 12 plus install and tuning 2500to 3000 more
stroker with itb , custom everything and oil control north of 50K
sc stage 3 7500
carls stage 2 6000
kuhn twin turbo 12 plus install and tuning 2500to 3000 more
stroker with itb , custom everything and oil control north of 50K
#23
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If I did the Kuhn TT kit, where would it be power wise? I'm debating whether to keep this and mod it or trade my dad for his Vette. I already gathered it will cost 10-12k for the mods I want to do to it and it will make right at 500 at the wheels on motor and run low 10s in the qtr mile.
I know the 928 will never be that quick, but if it could make over 500 at the wheels safely, it's on the table (esp for the same mod money). I know they are different cars, I just want to make 21st century power. My last VW was as quick as my 928 is with just a computer flash upgrade.
I know the 928 will never be that quick, but if it could make over 500 at the wheels safely, it's on the table (esp for the same mod money). I know they are different cars, I just want to make 21st century power. My last VW was as quick as my 928 is with just a computer flash upgrade.
#24
Personally i don't think you can get 500rwhp and do it reliablly, or at least not without a bunch of tuning and trial and error. My boost kit is probably around 400rwhp and does it easy without a lot of screwing around. Get past 400 and things will get quite a bit more involved. For a street car I have lots of top end power on reserve. I know some people talk about needing to get over 3000rpms before any boost kicks in on some kits, but with Victors kit I feel it immediatly when I touch the go pedal.
#25
Captain Obvious
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#26
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Gee a short visit to Kuhnperformance.com reveals his own car running 12psi claims over 570 whp, and that figure is typical of the 32 valve engine at that sort of boost level.
Colin's mid mount turbo is an amazingly effective and infinitely less complex installation.I personally dislike single larger turbos and particularly long hotsides, ie mid and rear mounts, but Colin's is hard to argue with.
I've actually been working on mine today, and I can't believe the enormous amount of detail work that goes into a Twin Turbo installation, that is why I'm quick to recommend Johns kit. It seems expensive but it took me untold hours to put mine together, it could have been cheaper to buy his kit or at least large chunks of it.
In my opinion Twin Turbos are the 'best' boost option, giving a wider rev range of torque increase, not suprisingly John points this out on his website. My own car starts to register boost at 1800 rpms and pulls like a train all the way to the rev limiter. I couldn't be happier.
In short it is the cheapest most effective means to achieve a most substantial power upgrade.
Colin's mid mount turbo is an amazingly effective and infinitely less complex installation.I personally dislike single larger turbos and particularly long hotsides, ie mid and rear mounts, but Colin's is hard to argue with.
I've actually been working on mine today, and I can't believe the enormous amount of detail work that goes into a Twin Turbo installation, that is why I'm quick to recommend Johns kit. It seems expensive but it took me untold hours to put mine together, it could have been cheaper to buy his kit or at least large chunks of it.
In my opinion Twin Turbos are the 'best' boost option, giving a wider rev range of torque increase, not suprisingly John points this out on his website. My own car starts to register boost at 1800 rpms and pulls like a train all the way to the rev limiter. I couldn't be happier.
In short it is the cheapest most effective means to achieve a most substantial power upgrade.
#27
Nordschleife Master
This statement makes no sense whatsoever. For the same USD and RWHP number, it is obvious beyond a shroud of doubt that forced induction motor will be more reliable. The main reason being that you don't need the high rpms to make the power with forced induction.
#28
Nordschleife Master
Personally i don't think you can get 500rwhp and do it reliablly, or at least not without a bunch of tuning and trial and error. My boost kit is probably around 400rwhp and does it easy without a lot of screwing around. Get past 400 and things will get quite a bit more involved. For a street car I have lots of top end power on reserve. I know some people talk about needing to get over 3000rpms before any boost kicks in on some kits, but with Victors kit I feel it immediatly when I touch the go pedal.
The early S4 engine is basically unbreakable as long as you avoid very high rpms, avoid high g-forces, don't let it knock, and don't live in the Death Valley in terms of cooling. It can make 500 ft-lb of torque 3000-6000 rpm all day, all night.
#29
Supercharged
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Fixed it for ya.
It is more involved. The higher the power the more complicated and costly it gets. No way around that.
If you want 500 at the wheels, I think the only options are Murfs Stage 3, or a TT system. I think the strokers are close to 500 but not quite there. My DR twin screw (extensively modified) now makes 490, but that's not quite 500...
I will say, there is a BIG difference between 400 and 500 on these cars. 500 gives you just enough power to feel a bit out of control if you're not paying attention. 400, while nice, just gives you a taste of what there could be.
I rode in a 800hp TT 928 last fall and OMG it was amazing. Very scary, but fun all at the same time. So maybe I just need to up my game and go to 600 HP next. It just costs time and money.
It is more involved. The higher the power the more complicated and costly it gets. No way around that.
If you want 500 at the wheels, I think the only options are Murfs Stage 3, or a TT system. I think the strokers are close to 500 but not quite there. My DR twin screw (extensively modified) now makes 490, but that's not quite 500...
I will say, there is a BIG difference between 400 and 500 on these cars. 500 gives you just enough power to feel a bit out of control if you're not paying attention. 400, while nice, just gives you a taste of what there could be.
I rode in a 800hp TT 928 last fall and OMG it was amazing. Very scary, but fun all at the same time. So maybe I just need to up my game and go to 600 HP next. It just costs time and money.
#30
Fixed it for ya.
It is more involved. The higher the power the more complicated and costly it gets. No way around that.
If you want 500 at the wheels, I think the only options are Murfs Stage 3, or a TT system. I think the strokers are close to 500 but not quite there. My DR twin screw (extensively modified) now makes 490, but that's not quite 500...
I will say, there is a BIG difference between 400 and 500 on these cars. 500 gives you just enough power to feel a bit out of control if you're not paying attention. 400, while nice, just gives you a taste of what there could be.
I rode in a 800hp TT 928 last fall and OMG it was amazing. Very scary, but fun all at the same time. So maybe I just need to up my game and go to 600 HP next. It just costs time and money.
It is more involved. The higher the power the more complicated and costly it gets. No way around that.
If you want 500 at the wheels, I think the only options are Murfs Stage 3, or a TT system. I think the strokers are close to 500 but not quite there. My DR twin screw (extensively modified) now makes 490, but that's not quite 500...
I will say, there is a BIG difference between 400 and 500 on these cars. 500 gives you just enough power to feel a bit out of control if you're not paying attention. 400, while nice, just gives you a taste of what there could be.
I rode in a 800hp TT 928 last fall and OMG it was amazing. Very scary, but fun all at the same time. So maybe I just need to up my game and go to 600 HP next. It just costs time and money.