Bad results on the Dyno

[clone]

RB20det GTS-t stock, only air intake

1. air / fuel not good
2. 194hp I think its supposed to be 245hp
3.back firing
4.plugs and coils are new (stock)

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After I found

1.the belts are vibrating like crazy at 5000rmp(guessing bad tentioner and old belts)
2.dirty air filter (waiting on a new Apexi)
3. found a hole in the exhaust (replacing with HKS)

just learning. any suggestions?

[amnash]

strip it. build it up from the ground! unless its ur dd then it will take a while

[nelsonmxmarc]

You said it's stock? 194whp isnt bad

Your AFR's are WAY too lean .. that is not safe..

[DreadedFist]

AFR's are lean as balls. Honestly, if your car is bone stock, 194whp seems high. They make what, 215 to the flywheel in stock trim, 20 years ago?

[Skym]

Safe A/F ratio at peak hp is 11.6:1. 12.0:1 is as lean as you want to go on stock engine.

I would check for exhaust manifold leaks, as can go that lean with exhaust leaks, as wideband o2 sensor picks up extra oxygen in exhaust that comes from manifold leak. Same with intake manifold leak.

Also check fuelpump pressure, condition of FPR (remove vacuum hose to FPR and see if fuel pressure rises 7.1psi or so).

My car was around 148rwhp (UK rwhp) when stock, which is around factory 215hp (UK hp) at engine. Once you add aftermarket exhaust, it's not stock anymore, as rwhp can increase by up to 24hp. I think that was around 10 years after it was built, when dyno run was done.

[clone]

I just figured out that the previous owner must of tuned it to:
-hoter plugs (which I put stock ones in)
-3" HKS exahust (which I went down to stock for insurance purpose)
-aftermarket fuel pump
-uped the turbo psi to ????

How dangerous are these readings, I am thinking of putting all that stuff back in and paying a tuner $400 to tuning it asap.

I was hoping to make it threw the winter.(yes, I dont have a winter beater yet-might get a civc)

[Shane_Sawatzki]

yah in stock form that kinda power isnt bad at all, but thats not a healthy 194 dont push that thing WOT to redline too much unless u wanna risk hurting it. Put the aftermarket stuff back in, do a compression test and then take it to have it retuned.

my old gts4 had 89,xxx km on it, blitz nur spec exhaust, apexi power intake, boost controller and an SAFC and it was a really healthy engine, i put down 212 rwhp at 13 psi and i wasnt even close to as lean as you. you dont want to get past 12:1 as skym said, then your just asking for trouble after that.

[M13]

that's a good result for stock 20 yr old 2L.

[clone]

chepper solution

Thanks for the the feed back.
I went to an other tunner he recomended put everything back in and throw in a AEM air/fuel gage $250. Then do a run hope everything evens out. if not tune from there.

[nismocan]

Ouch 11.6 afr is a bit rich, okay if your strip only but for a daily driver you are going to just wash the rings out of your engine. Stock motor on moderate boost it is fine to run 12.5 afr and peak at 12 , if your racing then by all means bump it up a bit to 11.5 or lower but not for daily driving. We have 4 imported cars we have been running now for years now either daily drivers or race and have no problems as of yet. Good dyno results and good exhaust temps

[DreadedFist]

Ouch 11.6 afr is a bit rich, okay if your strip only but for a daily driver you are going to just wash the rings out of your engine. Stock motor on moderate boost it is fine to run 12.5 afr and peak at 12 , if your racing then by all means bump it up a bit to 11.5 or lower but not for daily driving. We have 4 imported cars we have been running now for years now either daily drivers or race and have no problems as of yet. Good dyno results and good exhaust temps

Ignore this guy. 11.6 is perfect under boost, it's not like you are running 11.6 all the time, at all engine speeds and loads.

[nismocan]

Ouch that hurts to each his own.

[DreadedFist]

I wasn't being a **** :P

[clone]

thanks for the help again. It was running dangerously lean. I have learn't alot since my last post on this thead.
she's running great now!!! little rich at the end but Nistune should fix that..


Gained in horse power
-new splitfire ignision coils #7 plugs (fixed backfiring)
-timing belt, water pump, tentioner, idler bearing (probably why it spiked on the dyno)
-3" HKS cat back
-walbro fuel pump/ OEM sending unit (evened out A/F ratio)
-corroded wires to ecu/cam sensor (thanks rightdrive)

[MKIV]

Buy my tuned ECU
AEM FIC - Tuned by Tony at DMT

All you'd need is Gtr injectors and a 3" exhaust. My tuned ECU made 264whp at 14psi.