Jump to content
SAU Community

Recommended Posts

well finally got my r33 gts t to the dyno not heavily modded just stage 2 FMIC, apexi safc, 2.5 inch from the cat back exahust and 12 pounds of boost i obtain a 190kw at the wheels. "HAPPY? i dont know!" the guy who was tuning said he has never seen such an ugly power curve! from 4800rpm the curve is perfect shooting straight up but before that, it looks like a stair way all lumpy and shit at 4200rpm to 4800rpm it actually flat lines making no power. WHY IS THIS!!!

also how come on 7 psi at 4000rpm it makes roughly 138kw but at 12 psi at 4000rpm it makes roughly the same. a little help would be great.

Link to comment
https://www.sau.com.au/forums/topic/23376-why-wierd-power/
Share on other sites

Your turbo is too small. It takes more that you think out of the small t25 to keep up with the rb25's displacement and rpm's. This creates lots of extra heat going into your motor reguardless of the intercooler. May sound comfusing to you but I can almost gurantee its the problem. Why do you think the turbo makes boost so soon? Its too small.

Link to comment
https://www.sau.com.au/forums/topic/23376-why-wierd-power/#findComment-500234
Share on other sites

Originally posted by gtrhybrid

Your turbo is too small.

Er, no. Note his problems are before 4800rpm, not after. The turbo is a T3, btw.

ECR 33, the 4500rpm flat spot is a common problem with 25t's, but a safc + tuning usually sorts it out for most ppl (myself included). The factory ecu runs super rich and takes out a bunch of timing at non-stock boost levels. Cutting back fuel (afm load) on the safc should have corrected it. Does your tuner have much experience with rb25det's?

Link to comment
https://www.sau.com.au/forums/topic/23376-why-wierd-power/#findComment-500258
Share on other sites

Originally posted by ECR 33

2.5 inch from the cat back exahust

I believe your problem is this.

Replace the current exhaust with a 3" Turbo-back system and you'll gain a good 8-10rwkw across the board with noticable power gains in the 2,500-4000rpm area by freeing up the turbo and allowing it to breathe.

I created a thread here somewhere of a "before / after" dyno readouts when I got my standard front/dump/cat replaced with a 3" system. Ahhh here we go you can read up on it

here

Link to comment
https://www.sau.com.au/forums/topic/23376-why-wierd-power/#findComment-501185
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Wife wanted basket things in the wardrobe in our temporary house. Thought about ripping our the wardrobe and fitting the entire IKEA set, but it's a temporary house and we want to move in a few years. So IKEA advertises this as a 50cm unit, however the actually basket and rails measure 46cm wide. Only issue was depth, IKEA stuff is quite deep, where as the builder special junk is super shallow at less than 40cm. Send it, chopped the rails, then offset the mounting holes, job done, happy wife, less shit scattered all over the bedroom. Did the same to the other side too. Also drove the Skyline shit box today, dropped off oil at Supercheap Auto. I didn't realise they only now take max 2x bottles per visit. I visited 2x Supercheap Autos.  
    • I've seen similar actually in my situation. You never know what tables are attempted to be used when the car thinks it's -99C or +200C. The fail state is not usually that extreme but you know what I mean - it was in my case though! This is where being able to read all the sensors is useful cause you see this stuff really quickly.
    • The above is very important. However as long as you keep timing relatively low, it's plausible to make your own knock ears and plausible to learn to tune with a modern ECU that can do wideband O2 correction like a boost controller. I mean if you only have one viable road to even drive the car on, learning to tinker to this level may be worth doing given you can't do much else with the car...?
    • I find the fact that the rear plate has to be bent inwards at the rear not so bad: but the front is just awful: It's like come on. (these are my very old, now retired/turned in plates) TBH it is a lot of money to fix a minor issue, the fact I said "I'll never really spend the money on doing this" is why people ended up buying them as a gift for a 'car guy' who can be hard to shop for.. for car guy things.
    • I just bent the ends of my premo plates. It even went through Regency like that after the engine conversion and the inspector (a great bloke!) just squinted his eyes and said "I didn't see that". Plates, and how they look, are just something that have zero importance to me.
×
×
  • Create New...