Max Boost With Std. Intercooler

What would be the max boost that I can run with the std. Intercooler.

Some of these places like Viper motor sport say "slap on an exhaust and turn the boost up to 14psi" and you will be getting around the 160rwkw mark....

HOW TRUE IS THIS?

When I had the Stock Dyno Done I think Tim said that It peaked at 8.5psi then dropped to 7psi or something after 5500..

with stock everything except exaust/filter/and fuel pump I run 14psi without any trouble.

With a larger turbo this would be less..

What about the Hot 40 Degree Summer days?

Do you flick to a lower boost setting?

With Std cooler, but aftermarket exhaust, filter and remapped computer i run 13.5psi... its fine... one good thing to do would be to make a duct to your std cooler... thermo wrap the intake pip (the part that goes over the engine...) and put silver around that... should be fine to about 15psi :) wouldnt wanna go much over 1 - 1.1bar with std turbo tho

I actually think that skylines only go pop at 14psi if the fuel pump is suspect or if something else is wrong . Er.. A/F on my car was about 11.8 or so at 14.0 psi, so there's plenty of fuel there.

Er.. only have filter and exhaust.

oooh how did you wind up the boost?

Well my fuel pump is excellent apparently as tim when he dyno'd it put a fuel pressure reg. bleed kit as it was running way rich on full boost..
It ended up getting an extra 10rwkw from the fuel pressure reg. bleed kit.

<checks receipt>
The fuel pressure was $68.. Fitted and setup..
I got him to do a dyno diagnostics to see if there were any problems around the corner, I also wanted a dyno print out to go off of when I do the exhaust, filter, turbo and on the list goes. :)

Going from the dyno read out and that 2 psi gives around 10rwkw.
Starting from 125rwkw.
Exhaust around the 140rwkw mark
Boost from about 8-9 to around 14.
Should get me up around the 165rwkw mark.. I hope..

:flipa: R8 250kw Commodore

On stock intercooler and stock injectors and stock fuel pump and stock cams ie totally stock engine, except exhaust and air filter I ran 1.2bar (about 18psi) and got 420bhp at crank. It also ran at 1.3 bar (about 19.5psi) and got 440bhp, but turned it back down for safety.

The turbos are stock size but with steel wheels, to allow higher boost.

This was on my R33 Le Mans that I have now sold..........running fine with new owner.

However, it is obviously less hot over here in England, so I can't say whether it would be safe to run this boost in 30 or 40degrees centigrade.

Guy

UK GTR OWNER, GTS-t's my friend. Your GTR puts out more power than any of our cars even on stock boost :)

Hmm i think the KW figure varies with different boost control methods. I'm sure EBC's give a higher kw figure as they hold boost even at high revs as opposed to a bleeder where the boost is highest in the mid range. er.. anyone?

Hit the nail on the head SlowGts-t.

-Joel-,
Take note of the location of the other guys posting in this thread mate, UK & NZ, not the hottest places on earth, having been to the UK a fair few times, & living in Tassie for 1/2 my life (similiar climate to NZ) I know it can get very warm, but on average not like OZ (current temps in Adelaide & outer South Australian areas, mid 30's to over 45'c).

Now, I'm not sure with the 32 GTS-t IC, but I can assure you the 33 GTS25t IC (which is probably bigger?) will NOT cope "safely" with more than 10-11psi (YES!!! I mean 10-11psi) without some detonation. It may not be audible, & you might run it higher for a yr or 2, but it's not doing much good in the long term.

If you don't believe me on this, fill up with a tank of 98 fuel, wait till a cool night, go to a spot where you can go WOT a few times, set boost to 12+psi, & turn off the stereo & listen hard as you nail it in 2nd.

Or.... find someone willing to lend you their 32 GTS-t Power FC & watch the dash eng light (PFC uses it as a knock indicator) flash it's tits off!!! Don't think this option will be easy though :D

Originally posted by SlowGts-t
Hmm i think the KW figure varies with different boost control methods. I'm sure EBC's give a higher kw figure as they hold boost even at high revs as opposed to a bleeder where the boost is highest in the mid range. er.. anyone?


A good quality EBC (in fact most EBC's) will not only provide peak rwkw gains but also noticeable gains throught the rev range, as they hold the wastegate actuator line closed until the preset boost level is reached (ie:no wastegate creep & faster boost response) + they monitor the manifold boost level & then attempt to maintain that preset boost (opening & closing the bleed via stepper motors/solenoid as required).

But they cost big $$$:(, on a bang for your buck the humble bleed valve wins hands down.

Originally posted by UK GTR OWNER
1.2bar (about 18psi) and got 420bhp at crank. It also ran at 1.3 bar (about 19.5psi) and got 440bhp

How did you go about measuring BHP @ the crank??? eng dyno?

It is very difficult to compare the R33 RB25DET to the R32 RB20DET as I know the RB25DET will not handle much more than 10-12 psi without a fmic due to its high compression ratio compared to the rb20det.

I'm going to get the boost wound up on a hot day on a dyno as to make sure there is no detonation.

So when I wind the boost up I also have to change to a colder range spark plug and also change the gap to .8mm is that correct?..

Would any one have to plug part no. that they use for their r32gts-t running around 14psi?

True, very true, 9.0:1 comp' ratio RB25DET vs. 8.5:1 RB20DET.

Still, it's a good idea to set your max boost on a hot day (as you plan to do).

Plugs, you don't "need" colder range plugs, but it will help reduce the chance of pinging, although a colder plug can tend to foul easier too.
If you do go to a colder plug I'd only go 1 heat range colder (7's).
Reducing the gap to ~0.9-0.8 is a good idea to help prevent misfires.

I run copper NGK's, BCPR6ES's gapped to 0.85 & have found them to be very very good (RB25DET though).

I've tried standard Platinums, VX Platinums, & the new Iridiums (+ others) & have found the cheap coppers to work best of all (strange I know?) But they work, & @ less than $30 a set you can't go wrong (I change my plugs every 5k anyway). In fact a # of workshops around OZ have mentioned the coppers have given better results.

So do the Rb20DET's Run the same plugs as the RB25DET?

And 'BCPR6ES' is that the part no.. and are they the 1 heat range colder plugs?

Not sure if the RB20 / 25 DET run the same plug or not?, I'm tipping they would.

"BCPR6ES", or "BCPR6ES11" gapped down to 0.9-0.8, are the plugs I run, they aren't the standard plugs, but "I've" had great success with them.

6's are the standard heat range, 7's are 1 range colder (8's 2 colder & so on).

I'd suggest ringing Tim @ RPM, or Tilbrooks, & ask them what they recommend for the RB20DET, they'll have fair idea as to the best option for the local conditions/fuel etc...

Although I think Tilbrook don't recommend using Copper plugs? (if you don't like doing plug cx's go Platinum or Iridium).

Hey guys Just to add a bit...

Guys be very careful when you run >12 PSI on a Stock RB20DET fuel system! Dont be greedy. You will need a AFC or somthing like that to prevent your engine from running lean.

I myself did not know (or suspect!) that I was running lean @ 13PSI until I checked my A/F's on a Dynojet! Dont trust your stock o2 sensor/AF gauge either.

I actually made more power at a lower boost level with stock ECU and fuel system... no Sh!t

hrmm thats strange running lean..

I'd say your fuel pump is on its way out.

When I had the std fuel pump i was running 12.5psi and made 152rwkw with a fuel pressure reg. bleed kit to lean her off a little.

Then I ran 14psi boost and still had to lean her off a little.

THEN.. I fitted a bosh 910 fuel pump and it ran way rich all the way through the rev range and now i can only get the right AF's either in the mid and run the top end a little rich or run it lean in the mid and have perfect top end mixtures..

So well I've decided to be safe and run the mid perfect and the top end rich.

Still made 156rwkw on 14psi boost in the mid but it drops around to 12psi over 6000rpm. (weak actuator spring)

New turbo soon gt2530.. :) <grins> Then a full ecu tune :)

The beauty of the 32 ECU.. :)

Yeah I run a bit lean at top end too with 12psi, modified computer chip (no idea what tho it was like that when i bought it) 3" TRUST exhaust with HKS Downpipe and filter... any suggestions how to fix that?

Originally posted by [TWUBLE]
Yeah I run a bit lean at top end too with 12psi, modified computer chip (no idea what tho it was like that when i bought it) 3" TRUST exhaust with HKS Downpipe and filter... any suggestions how to fix that?

Go grab yourself a GTR fuel pump off a wrecked one or just order one, they flow their asses off. Don't remember the number Ben quoted to me but I do remember it was really high :D

Your car makes nice power Joel!

Ok..well meybe everyone's car is a little different

The first thing I replaced when I bought my GTS-t was the original fuel pump as the old one did not last long...

So with a low milage new pump I assumed i would be fine rinning 13PSI based on what I read in the forums. I turned up the boost and drove around merrily not knowin I was running lean until my first dyno session with a reliable A/F meter checking mixtures. Also my car is a auto.

For safety, I am definatly going to upgrade my fuel pump anyway since my car seem to be leaning more than the average GTS-t.

My point is it is best to find your safe boost limit on a Dyno rather than turning up the boost and hoping for the best ;)