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[Kribside]

Hey guys i just put in a turbotech boost controller to my r32 gts4. i've set it to about 13psi. it hits this initially but then constantly drops off to below 10 psi. even before i put in the boost controller i could see the boost rarely held but it would only drop by 1 psi max. i took off the BOV to eliminate a leak there (advice from a mechanic) but even without it, the boost wont hold.

any suggestions would be greatly appreciated

thanks heeps

[bubba]

I'm using the turbotech boost controller on my r32 gtst, running 13-14psi, it does drop off slightly but only to 11-12psi, not below 10. Not too worried, it's all temporary because as soon as I get some management the RB25 turbo and R34 injectors are going in

[mad082]

if it is dropping below 10psi then i'd say the actuator is stuffed. the actuator is rated to 10psi so that is the minimum it should hold.

or there is a major leak somewhere.

[jeffworld2]

do you mean the first few times you gun it it gets to 13, but later it stops at 10? that sounds more like management problems to me

[Kribside]

every time i gun it it reaches 13 then it drops... sometimes it holds longer than other times. im baffled

[murrayis]

does it only start to drop off after about 5000rpm?

[Kribside]

uhhhh i havent been watchign the rpms... only the boost, next time i take him out ill take note and get back to you!

[bazr33]

mines doin that on my hiflow r33 turbo

excepty mines sitting on 18psi, dropping to 15psi

and actuators on r33 turbo is 7psi, so yours should be holding.

i would be leaning towards the actuator is stuffed or turbo leak

[bubba]

when you say it drops below 10psi, how far below are we talking? 9psi? or less than 5psi?

[jazza08]

I'm using the turbotech boost controller on my r32 gtst, running 13-14psi, it does drop off slightly but only to 11-12psi, not below 10. Not too worried, it's all temporary because as soon as I get some management the RB25 turbo and R34 injectors are going in

You can't put 34 injectors in an rb20 unless they are GTR and why you'd bother if your gettin a stock r33/34 turbo i don't know... waste of time.

For the boost issue, get yourself a decent actuator (HKS etc) with a 14psi spring and it will give the boost controller nothing to do Or even an rb25 one at 10psi and the boost controller should be able to make up and hold the extra 4psi no problems, if your tryin to make an average boost controller make the actuator do 100% more ie double what its supposed to of course you'll have some problems! Upgrading the actuator would be the easiest way to get what you want i think

[bubba]

They are top feed injectors, apparently of an R34, eitherway I have the rail they came with and a smart mechanic for $50, if they are good, then there no problem.

For $300 the RB25 turbo shall be a nice upgrade while I save for an r33 frontcut and I will be using the RB25 actuator with the RB25 turbo.

Not everyone has cash to throw around so why bag on cheap yet effective (hopefully) upgrades. A real waste of time is spending thousands on your RB20.. an RB25DET is a better place to start.. too bad they only came in boats

Edited November 17, 2006 by bubba

[jazza08]

Im not bagging you at all, just don't waste your money on those injectors, ull need a re-tune and they won't make any more power, ive seen rb20 injectors flow 280rwhp and you won't even make that with a standard rb25 turbo on 1bar ++ of boost... Save your money on the injectors

For the amount ive paid for 300rwhp outta the rb20 i would have a pretty much standard rb25, so i disagree on it bein a waste of time but rb25 is an awsome upgrade in an r32 thats for sure!

[bubba]

Management is the bit that's got me stuck the injectors only cost me $50 with a rail and are a darn sight newer than the stock ones, so so if they work, cool - leaves a fair bit of safety with the duty cycle - if not, whack the standard ones back in.

I'm trying to decide whether to get a dyno tune and remap once it's done for about $700 OR saving a bit more for a powerfc as long as someone could convert it back to rb25 setup. I can't really justify the $1500 for an AP Eng powerfc if I can't use it on the next engine

What kind of setup are you running jazza?

[mad082]

an RB25DET is a better place to start.. too bad they only came in boats

a r32 with a full tank of fuel weighs the same as r33 with a nearly empty tank. they are 4% heavier, but have over 20% more power.

but yes, an rb25 is a much better place to start. a guy in town just spent $8000 doing up an rb20. he put a stupidly big turbo on. he makes full boost at 5800rpm, and his redline is at 7200rpm. max power is just under 250hp (~185kw), and off boost it is hopeless. now for a darn sight less than $8000 he could've bolted a stock rb25 in and made the same power and had a much nice car to drive.

[jazza08]

Well he obviously has NO idea really because to make that power with that lag is fkn stupid anyway, the weight differences between a R33 and R32 ARE noticeable, id know there is both cars sitting in my driveway, the 32 is much more nimble but the 33s motor means you don't notice it much in a straight line. The injector deal for $50 sounds incredibly cheap, if you can make em work then for your reasons i agree with what your doing.

I have done most of the bolt on mods, turbo with gate, injectors, pump, cooler/zorst, boost controller etc etc

Makes 300hp @ rears with full boost (20psi) by 3900rpm which is plenty fine for the street, to tune it i simply got the ecu rom'd and remapped!

My mate has the EXACT same mods on his rb25, ie same turbo + supporting mods inc injectors etc and makes 324rwhp on about 18psi and full boost by 3100rpm... is it worth spendin 5k+ to get everything set up properly on an rb25 for 24rwhp more and 800rpm less lag? Yes it makes more torque down low but i can't justify the expense unless you are going for 400+ hp, then the rb20 is just no good and you should look at a built rb25 or rb26

Edited November 18, 2006 by jazza08