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Just got a dyno of my car (HR31 Coupe), its making 127rwkw. Its basically stock standard with a 3" split pulse dump, full exhaust, FMIC and splitfire coils.

Now its running very rich in the midrange (pretty normal for the redtop ECUs), down to dead on 10:1 at about 5000rpm. Goes back up to 11 ish up higher up and then back down to 10 again. You can see big holes in the power curve where it richens up when I compare it to the afr graph.

Now I dont plan to do much to this motor, probably a stock rb25 turbo when the standard one gives up the ghost but aside from that that is all. Now Im thinking a SAFC might be a good bandaid fix to this problem, lean it out to 12.5 through out the range should pick up ~20kw? in the middle where it richens up and smoothen out the power delivery. I know a full ECU would do a much better job, but at $1500+ installed and tuned for a decent ECU it seems like a waste of money considering my plans for the motor. I may as well put that money towards a better car with all the goodies already.

What are your thoughts, Boostworx quoted me $250 installed and tuned for a SAFC which seems like a cheap option.

The turbo on those early RB20DET's was tiny and woeful so its really the first thing to attack , R32 GTST turbo or R33 GTST turbo would be good . You may find that they'll make better power and lean out the AFR's at the same time . RB20 turbo (R32) would probably be cheaper because of their percieved value . I can't remember if oil and water lines were different but if you get those from the R32 it should in theory all go bolt .

Cheers A .

The ECCS model actually had a much better turbo very similar to the silvertop, the NICS model is probably the one you are thinking of which is terrible and chokes after 5000rpm.

Either way when this turbo dies Im gonna replace it with a stock RB25 turbo. I doubt they will lean out the ratios out though, it would probably be just as bad.

Yeah you may aswell just go SAFC is you're not gonna do too much to the engine - powerfc would be overkill - especially when you price one for an sr20...

Edited by Mr Italy!

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