Stock GTST rwkW?

[king_kw13]

Hi guys

I was wondering for a stock R33 GTST what is the 'average' (if there is such a thing) rear wheel kilowatts.

From the flywheel it is around 185kW?

I read in a performance mag that rwkW is around 120-135. WTF? Is there that much kW lost? That would be pretty inefficient then.

Also, what effect would 3" dump back zorst do to that rwkW? How much on 'average' increase in kW would you expect?

Cheers

kW

[Lepperfish]

Mine had about 120rwkw.....

[king_kw13]

Really? Is that stock?

[sewid]

Depends on the dyno, and the conditions like ambient temperature. I would say 125rwkw @ the rears would be pretty average from my research around various forums.

Best way to find out is go get it dynod!

[king_kw13]

Is there really much need to get it dynoed if you only got zorst and bleed valve and no other engine mods?

[qikr33]

For a start i dont know if u got it but i would get a filter ,either pod or in box k&n.A dyno will help your car run its optimum for the set up u have .Some dyno places recon they can get another 10=15psi just by dyno tune ..With the standard ecu there isnt tooo much to change.I would get it dyno to give u a starting figure before any mods.Also my r33 ran better at 10psi than it does on 12 psi,so things like this u can set up on a dyno.

[king_kw13]

qikr33 what is your rwkw with all those mods?

do u have an ebc or a bleed?

FMIC?

[rev210]

Is your gtst BRAND NEW ?

If not quoting 'average' figures for 100,000km worn engines is well.... Stupid. This sheds some light on the authority of the so called 'performance mag' to quote such figures.

[hippy]

even though it isn't brand new ... its still gives a fair idea doesn't it ... not exact but close enough??

[rev210]

hippy,

No it doesn't.

The wear characteristics vary alot. I drove serveral 'stock' vehicles before getting mine and I can tell you that there is a large varience on the power with high km cars.

[Sydneykid]

Hi guys, we have had over 20 standard R33 GTST's on the dyno, with kilometres from 10,000 top 130,000. The power output hardly varies in Shootout mode with temperature and humidity compensation loaded. The only time we see low numbers we find poor compression or other problems, fuel pumps, fuel regs, plugs etc. If it leaks down less than 25% and the support stuff is in good condition, they always make 120 to 130 rwkw.

We have found the same with RB20DET's, they are very consistent and always make 105 to 110 rwkw. We have had a couple with close to 200,000 kilometres on them and they test fine. Maintenance (regular oil and filter changes etc) seems to be far more important than age or kilometres travelled.

So to answer king_kw13 question, 50 to 60 kw losses through the drive train are very common.

As the REV said, they do vary, but we generally find that ones down on power have a support system problem or are badly tuned. The engine internals are generally pretty good and they come up well once we fix whatever the problem is.

We do find really bad ones, but they are rare. We had a 120,000k one in a couple of months ago that I removed the cam covers off and found great lumps of "vegemite" everywhere. Sent the gunk off to a chemist mate at Castrol and he reckons it had never had an oil change in its life, it was still the original running in oil.

Hope that adds to the discussion

[rev210]

sydneykid,

if they go to 'your dyno' maybe they might get an idea. What if they are in Mexico city at a few thousand feet above sea level?

BTW a statistically valid sample is greater than 30, your only 10 cars away.

[Sydneykid]

Hey Rev

It was mentioned it was in SHOOTOUT mode, so the variables were taken into account... The whole purpose was to show "consistancy" not an exact figure of what each car produced...

Son of Sydneykid

[Doctor]

I think with 20 cars you would get the idea. And because its an Australian forum no one here is going to place there car on a dyno somewhere in Mexico or a few thousand feet above sea level.

[Sydneykid]

its all done on one dyno in one wharehouse and run by someone who sets it up every run for the correct variables to an ambient temp of 24degrees celcius... it makes for a good comparison at minimum and a good general idea, even for anyone who wants to question its morals

S of S

[Guest Oz Elitesport]

king kw13 also asked what difference a turbo back zorst makes compared to standard. Anyone??

oz.

[rob77]

when my car was dyno just after getting it off the ship it pulled 97kw@rear wheels, that was bog stock standard same way it left the dealership when brand new. After a good cat back exhaust and a small amount of timing it went to 115kw@rear wheels. I've used the same dyno pretty much each time since then. After fitting the front mount, boost controller and HKS pod it made 179kw@rear wheels (boost set to 12psi) and then 183kw@rear wheels after fitting the dump+front pipe. I would say if I fit an aftermarket ecu next I'd be able to just get over 200kw. But the odd thing is the dyno figure my car gave when it first got here, I'm not sure what boost it was running back then (no decent boost gauge and didnt ask the dyno guys if they measured it), anyway the power levels seem on parr with the other guys in WA with simular mods.

[Sydneykid]

a split dump turbo back exhaust, as opposed to a single turbo back exhaust, is good for almost as much power as what you gain from a cat back. But a tuboback and catback exhaust is only as good as the cat itself. A full split dump turbo back, hi-flow cat and cat-back should be worth about 25-30rwkw.

S of S

[rob77]

With my new turbo we will be making a complete seperate wastegate to exhaust dump+front pipe, they will join back in together just before the cat.

[rev210]

Originally posted by Sydneykid

a split dump turbo back exhaust, as opposed to a single turbo back exhaust, is good for almost as much power as what you gain from a cat back. But a tuboback and catback exhaust is only as good as the cat itself. A full split dump turbo back, hi-flow cat and cat-back should be worth about 25-30rwkw.  

S of S

Split dump pipe is a superfluous modification, a well made one peice is just as good and often cheaper on the stock turbo.