Absolute maximum power through the rear wheels
Absolute maximum power through the rear wheels
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sleep envy

Original Poster:

62,260 posts

279 months

Thursday 2nd November 2006
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Been reading about people tuning forced induction engines to plus 450bhp and having been in a spin in VS's old 993tt (pre tuned state so around 400ish bhp - where he still scared the shit out of me), I've decided 300 bhp is more than enough to get myself into, and just about, out of trouble.

The idea of owning (I'll forget about taming) a GT2 is out of the question as I know I'll lose my licence within a week.

Similarly, I reckon a tweaked TT with 4wd would be easier to deploy full beans more of the time, meaning I'd keep my licence for an extra week.

How much power can you realistcally tune a RWD car before it all gets too silly to use on the road.

to keep things simple I'm ignoring TC and LC systems 'cos my RS only has organic versions of these i.e. my right foot

fidgits

17,202 posts

259 months

Thursday 2nd November 2006
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you kinda answered your own question there...

There isnt a specific figure - it's all down to driver ability - (ignoring the TC/PSM) 300bhp can be far too much for some people, others can easily handle double that...

all about skill and talent im afraid..

fidgits

17,202 posts

259 months

Thursday 2nd November 2006
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By the way, in answer to your literal last question - I believe some Toyota Supra's in Japan have been tuned to 1200bhp...

stuttgartmetal

8,164 posts

246 months

Thursday 2nd November 2006
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In this case how about half a shitzu ?[ No idea what that is in Nm]


nel

4,830 posts

271 months

Thursday 2nd November 2006
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sleep envy said:
How much power can you realistcally tune a RWD car before it all gets too silly to use on the road.


It kind of depends if you want to use the car when the roads are wet and greasy! If you could guarantee nice dry, summer roads then the GT2s, Rufs and Turbo 2s that can be tuned to over 600 bhp would be fun but challenging. However, when the going is slippery I'm not sure that they'd be that much fun to drive...

I'll admit that I frequently regret having a 4WD turbo....until it starts raining and 4 wheel powerslides on wet roundabouts remind me of the advantages! Still, it is a damned shame that 993 GT2s are so expensive because that would be my choice.

sleep envy

Original Poster:

62,260 posts

279 months

Thursday 2nd November 2006
quotequote all
stuttgartmetal said:
In this case how about half a shitzu ?[ No idea what that is in Nm]




yeah but that's been converted from 4WD to FWD

fidgits

17,202 posts

259 months

Friday 3rd November 2006
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Gazboy said:
fidgits said:
By the way, in answer to your literal last question - I believe some Toyota Supra's in Japan have been tuned to 1200bhp...


Some yanks claim over 1500bhp at the wheels BUT it seems their way of measuring power on a chassis dyno is somewhat different to ours


Also - generally for those supra's, they have drag car rear wheels/tyres rather than road setups... so IMO they dont count..

fidgits

17,202 posts

259 months

Friday 3rd November 2006
quotequote all
Gazboy said:
fidgits said:
Gazboy said:
fidgits said:
By the way, in answer to your literal last question - I believe some Toyota Supra's in Japan have been tuned to 1200bhp...


Some yanks claim over 1500bhp at the wheels BUT it seems their way of measuring power on a chassis dyno is somewhat different to ours


Also - generally for those supra's, they have drag car rear wheels/tyres rather than road setups... so IMO they dont count..


They are actually road legal tyres, in much the same way that you can get road legal tyres that resemble cut slicks (like the M3CSL's tyres).


ahh, i saw a picture of 1200bhp supra with the drag rear wheels... havent seen any US 1500bhp ones..

fidgits

17,202 posts

259 months

Friday 3rd November 2006
quotequote all
Gazboy said:
fidgits said:
Gazboy said:
fidgits said:
Gazboy said:
fidgits said:
By the way, in answer to your literal last question - I believe some Toyota Supra's in Japan have been tuned to 1200bhp...


Some yanks claim over 1500bhp at the wheels BUT it seems their way of measuring power on a chassis dyno is somewhat different to ours


Also - generally for those supra's, they have drag car rear wheels/tyres rather than road setups... so IMO they dont count..


They are actually road legal tyres, in much the same way that you can get road legal tyres that resemble cut slicks (like the M3CSL's tyres).


ahh, i saw a picture of 1200bhp supra with the drag rear wheels... havent seen any US 1500bhp ones..


CRD? They chopped out the innder arches, lost the irs and put in a live axel and absolutely huge drag slicks, and were promptly disqualified from the event they wanted to win in the first place.


thats the chappie...

identti

2,389 posts

255 months

Friday 3rd November 2006
quotequote all
fidgits said:
Gazboy said:
fidgits said:
Gazboy said:
fidgits said:
By the way, in answer to your literal last question - I believe some Toyota Supra's in Japan have been tuned to 1200bhp...


Some yanks claim over 1500bhp at the wheels BUT it seems their way of measuring power on a chassis dyno is somewhat different to ours


Also - generally for those supra's, they have drag car rear wheels/tyres rather than road setups... so IMO they dont count..


They are actually road legal tyres, in much the same way that you can get road legal tyres that resemble cut slicks (like the M3CSL's tyres).


ahh, i saw a picture of 1200bhp supra with the drag rear wheels... havent seen any US 1500bhp ones..


Look on SupraForums. Some claim over 1300whp which equates to around 1500bhp! Dosen't mean that they're drivable though, and I bet they're completely out of control on a track. I think the amount of power through the rears is totally dependant on the car it's in.

Touching Cloth

11,706 posts

269 months

Friday 3rd November 2006
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anonymous said:
[redacted]
biglaugh


I think that is Charlie's latest idea, a rolling road adapter kit for animals. Started out as a project to see if all horses did actually produce 1HP, or if indeed the Japanese had been breaking the terms of the gentleman's agreement and breading horses that "kicked out" (see what I did there) 1.5hp or more. Anyway after successful trials it was realised that the kit could be downsized to fit all manner of animals; the dog market was an obvious target given the propensity amongst dog owners for pub talk about how fast their dog could "fetch stick".

Brett928S2

1,504 posts

245 months

Saturday 4th November 2006
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Hi

In my 928 (4.7 ltr) ,,,it has 310 hp as standard....plus my Nitrous...when I hit the switch...it goes to 500 ish hp...but in a straight line only....you wouldnt want to hit the switch on a bend lol

Next year ...I will be upping the Nitrous to aim for around 1000 hp....but for straight lines only....for driving with that hp constantly....including bends..you would need a VERY special car....like a VERYON lol

But most people dont want 500 or 1000 hp in bends...you want it when that annoying Lambo or Ferrari thinks he can overtake you....THEN you hit the switch and walk away from them....huge fun ..and when the switch is off...its just a normal car...

All the best Brett

Edited by Brett928S2 on Saturday 4th November 01:44

RedRSR

332 posts

286 months

Saturday 4th November 2006
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Brett928S2 said:

But most people dont want 500 or 1000 hp in bends...


Why...do most people not know how to use a throttle pedal

aww999

2,078 posts

291 months

Saturday 4th November 2006
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Forced induction on a road suspension setup with road tyres can be a real handful, as in the pursuit of big power people fit big turbochargers (myself included), so you can often get a big spike in power as you cross the turbos boost threshold rpm which can break the rear wheels loose. You also have old-school turbo lag as you try and meter out the power in bends. Not the most refined way of going from a-to-b but certainly fun!

I have an old-shape supra, Garrett T67 turbo,all supporting mods including fully-mappable aftermarket ECU. The peak horsepower figure I ever saw was around 580-600 at the wheels, at (I think) 28psi boost on 118 octane race fuel. In that tune, the car was almost undriveable (by me, anyway!) on road tyres; it would just ignite them as it crossed 4000rpm in fourth gear on anything over half throttle even in a straight line. This was on 275 Eagle F1's in the dry! Could have gone down the route of fitting Nitto treaded drag radial tyres but their soft sidewall would have made the car a real "straightline special". Have detuned the car to around 375bhp at the rear wheels on pump fuel and I enjoy it more now than before, even though it's "slower"

I would be the first to admit that this 80's GT is not the best platform to thrust 700 crank horsepower upon, a decent chassis could certainly handle this much power channeled through the rear wheels without the sheer terror (I'll admit it!) that I suffered from.

My toher issue though, was that I only really enjoy driving when I feel like I'm wringing the cars neck to some extent. With huge BHP on the public road, opportunities to feel the best that your car has to offer are very limited, so you can often end up feeling short-changed.

verysideways

10,271 posts

302 months

Sunday 5th November 2006
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Have to say i'm not sure i agree with the question, since the amount of horsepower isn't ever going to be a problem in a straight line but the rate at which that power is developed (torque) is key.
I used to sling around 450lb/ft around every day and it was awesome, but it kept me very much on my toes.

In the rain i could NEVER use full throttle anywhere near 4500 rpm (this is 4wd remember) as the resultant spike from the overboost would put me at close to 500lb/ft and that made all four wheels spin at 90mph on the M4 on one particularly noteworthy occasion!

In the dry it would shred the tyres as full boost came in whilst in 2nd gear, and would squirm in third. I'd say a standard 993tt is just about right for most conditions at 398lb/ft (with the standard Porsche map, which is very progressive).

sleep envy

Original Poster:

62,260 posts

279 months

Monday 6th November 2006
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verysideways said:
Have to say i'm not sure i agree with the question, since the amount of horsepower isn't ever going to be a problem in a straight line but the rate at which that power is developed (torque) is key.
I used to sling around 450lb/ft around every day and it was awesome, but it kept me very much on my toes.


but Pete, that was 4wd...

if your tt was rwd I'd have never jumped in hehe

Davey S2

13,394 posts

284 months

Monday 6th November 2006
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The 911 FF GT2 has about 780bhp iirc

sleep envy

Original Poster:

62,260 posts

279 months

Monday 6th November 2006
quotequote all
when it's not broken...