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Need More Down Low For The Track.

SIR-JD

By SIR-JD,
in Engines & Forced Induction

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SIR-JD Rising Star

SIR-JD

Posted
Posted

Hey guys, I have a 32gtr. The engine has everything under the sun done to it. It has -5s and makes great power. The problem is not great power figures it's low down power out of corners. I'm thinking this problem may be due to 280 cams in it. What do you guys think? The car has been very finely tuned so I don't expect this.

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MBS206
MBS206

Stand on throttle earlier. Use attessa to point you in the right direction.

jimboppins2230
jimboppins2230

couldnt you start messing with the diff ratios?

SIR-JD
SIR-JD

Yeh larger capacity isn't an option as this is already a fully built 26.

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SIR-JD Rising Star

SIR-JD

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It is a2.6ltr, 98 octane fuel with octane booster the tune was done by dr drift then by cosmic performance.

It sound like people are making great power and response from the stock cams. But I'm not sure they would use all of the rev range up top that the engine was built for...

Cheers guys!

Piggaz Grand Master

Piggaz

Posted
Posted

Have you considered using the next gear down, to keep the engine in its power band?

What if you're at 4000 in second... Not quite enough on a massive cammed 2.6 with 5's to really get a wriggle on.... You're not gonna go back to first are you?

33GTRV Mentor

33GTRV

Posted
Posted

The boys pretty well have it nailed for you mate. Jew brew, smaller duration cams, this is depending on what has been hacked out of the head as well, a good free flowing exhaust, a good cold air system and some time on the dump with a set of cam gears. Failing that, a 6266 is a good option.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

It is a2.6ltr, 98 octane fuel with octane booster the tune was done by dr drift then by cosmic performance.

It sound like people are making great power and response from the stock cams. But I'm not sure they would use all of the rev range up top that the engine was built for...

Cheers guys!

So what are you spinning the motor up to exactly? Because realistically you wouldn't build a motor to spin to 9,000rpm+ and then put -5s on it as there is no need.

My stock cams were fine to 8500rpm for example with -5s... Power had not fallen off at all.

280s are madness either way for -5s, terrible match

Sinista32 Grand Master

Sinista32

Posted
Posted

Potentially get flamed for suggesting this. Oh well here goes anyway.

Guys above I believe are on the money. DO this ^

do you run a Torque/split controller ?

considered replacing your OEM G sensor ? with a Do Luck Tarzan G or the Midori unit.

discoPumpkin Community Regular

discoPumpkin

Posted
Posted (edited)

the mines 34GTR is so responsive coz of the diff ratios despite the 2530's on RB26. Either a 4.11 or 4.4 ratio would be off tap, obviously the top end end would be compromised a bit, but who cares

mines GTR response is unreal

Edited by discoPumpkin
Roy Grand Master

Roy

Posted
Posted

You are all missing the point. Odds are it would be cheaper to get the thing through the corners quicker...then you have more revs on exit and more revs means more power.

So what suspension and tyres/rims size are you running. Cams or no cams -5s can work perfectly well on a 2.6L so if the thing is laggy on exit I think you need to get through the corner quicker

XGTRX Veteran

XGTRX

Posted
Posted

You are all missing the point. Odds are it would be cheaper to get the thing through the corners quicker...then you have more revs on exit and more revs means more power.

So what suspension and tyres/rims size are you running. Cams or no cams -5s can work perfectly well on a 2.6L so if the thing is laggy on exit I think you need to get through the corner quicker

Totally agree.

Driving style is another.

How long is a piece of string.

If your at a tight track you may suffer but at a faster track it may be perfect. Set up is about compromises and wont be perfect for every corner. Just keep trying to get your lap-times down. I would be listening to Roy before i go touching the engine.

Joshbigt62r Proficient

Joshbigt62r

Posted
Posted

Yeah but massive lift big duration cams (280*) are made for a gt42 45 55 ect sized turbo. Just not really suited to smaller twins. Twin 3037s and a 1/4 drag strip is a different story. Tomei type b's are tried and proven with -5's on the track and even a drag strip strip. As R31Nismoid said -5's and 280* cams are just a extreme mismatch. I do also agree with roys comment to a extent as well.

Cheers josh

discoPumpkin Community Regular

discoPumpkin

Posted
Posted

omg, OP never once stated getting a bigger engine was an option, oh and the RB26 has to be one of the best know motors for track use for it's mid to top end power, reliability and revs.

I agree with Jim and changing the diffs, and the other guys in swapping the cams, and finally making sure it has good soft tyres for grip to enter the corners fast as poss. That will make a big difference to response

SIR-JD Rising Star

SIR-JD

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Thanks for all your responses guys. I know the cams are to big (they were in when I got the car). I run semi slims and custom coilovers on the track. I'm not sure that corner speed is the problem. Eg on sandown in the tight section it feels like I should be cornering in third but find that to get good power down out of the corner I need to be in second. Second I need to rev the car to 9+g and third is a bit sluggish out.

Would my engine specs help?

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