R33 Stage 1 Mods Vs 300zx & Soarer...dissapointed

[MBS206]

No power? Off the mark?

I have FMIC,

Clutch/light flywheel

Full exhaust

Boost controller

Tuned

And I STRUGGLE to get off the line. For one reason. It's called WHEEL SPIN!

I light up at the drop of a hat off the mark. The RB20 struggles off the mark COMPARED to an RB25.

But the RB25 is no slug whilst off boost.

[govich]

I still think GTST needs to rev too hard before you see any power, all the dyno charts I see are really peaky, which means almost anything down to granny's vdub can do you on take off.

Have a look at some dyno charts from engines without ridiculously large turbos attached to them. From my own dyno sheet the engine sees 12psi from 2700rpm (stock turbo), with ~95rwkw at 3000rpm. From a fairly conservative estimate of 110kW at the crank, that converts to around 350Nm of torque, which is a big chunk for a 2.5L engine at that speed..

Edited August 16, 2007 by govich

[WhiteHot_R33]

Hey vault13 as everyone else has said get a dyno run and proper tuneable ecu. . .

I know that i was pretty annoyed with the lag in my car without an EBC as it didn't get full boost until 4500 rpm and then it took off. . . no mid/bottom end at all.

with a Profec B and PFC the car is incredible on the street, full boost by 2700 RPM and I sometimes short shift whereas I used to have to go to redline so i didn't drop off boost.

they are only $385 now from some traders and really do make a difference!

so does a PFC!!

[swanny180]

Mate, dont even think about spending a cent on buying management/boost controllers/anything else at this stage, its simply pointless.

Get a dyno run mapped against boost pressure, then figure out where the problem actually is.

Youll be able to see rpm vs boost vs power, and get an idea of whats actually happening.

You might find boost doesnt build untill very late for a stock turbo (say 4000rpm), then makes reasonable power to redline (say 200kW). This would indicate that theres probably a problem with the actuator, or perhaps a boost leak from a cooler pipe.

You might find boost builds at a normal rate (ie 12psi by ~2700rpm), but power is poor until higher revs. This would indicate its more likely a problem related to timing (possibly physical crank timing, possibly in the tune).

Basically, you wont know what you will find though, till you actually get it done.

For around $50 its gonna save you a lot of hassles whilst troubleshooting, and youll most likely find its something quite simple.

No point spending a few hundred on an EBC to find that the tune is rubbish, and no point spending a few hundred on a PFC and tune when your turbo wasnt making boost till high rpm...

Trust me, youll get much better advice and a lot better understanding if you have a dyno graph to help you understand whats happening

Let us know when you get one done!!

[Chi100188]

mmm i don't think the RB25 is a slug, i've given a twin turbo manual soarer with 2 equivalent T28 twin turbo set up but complete stock car apart with 3 inch zorst and i kept up and i have FMIC and 2.5 inch zorst non tuned so yeah get it checkd out b4 spending big money mate cause the 25's aren't that slow ! haha ur case is abnormal matey ^^

Cheers

Chi

[SECURITY]

there has got to be a problem with your car.

the ecu i sold you was doing my head in for DAYS. i was tossing up between selling it and keeping it and i couldnt make up my mind. it felt way better than when i had my safc in.

i bought the ecu off someone who was running it on a stock turbo gtst also with 'stage 1 mods'. i was running it on 15psi also with a standard exhaust. it would make me wheel spin through 2nd and 3rd. sure its through a hiflow turbo but even on 10psi (ask MANWH0RE when i was testing it out he was in the car with me), it spun through the rev range and through gear changes also with the standard exhaust.

im going to say from what ive read, your timing is out and by a fair bit too. get it fixed up and im sure you'll have the same results.

[Nismo_God]

chuck it on a dyno....

but my car with stock turbo/ecu and turbo back exhaust and fmic and 12psi made full boost by like 2300rpm and 200+rwkw so something isnt right there...

[vault13]

Thanks to those who made suggestions.

I bypassed the stock solenoid and the boost seems to build quicker.

It still only hits peak boost around the 4-4.5K mark though, still feels slack at low revs.

When I eventually get a tune I'll throw a chart up if anyone's interested.

BTW does anyone know if there are any tuners in Bris or Toowoomba who can tune the H8 chip in this chipped ECU?

[rev210]

You know getting a fairly stock R33 manual running mid to low 13's on its 'factory' sized rubber is very easy.

http://www.skylinesaustralia.com/forums/in...showtopic=66556

here are a few things to look at.

* replace the wastegate actuator with a factory one to test.

* Check everywhere for air leaks, including all vacume hoses and the cheap ass intercooler core you bought. This is a pain is an ass but, in your case necessary.

* Check your base timing settings, add a little timing.

hope that helps

[femno]

When I eventually get a tune I'll throw a chart up if anyone's interested.

mmm i dont think youre completely understanding what people have suggested.

You dont need to have it tuned on the dyno as yet, ie have anything changed, you need to put it on the dyno so you can see what the afrs, boost and timing are doing and see why the power sucks.