Dyno result 15hp missing

[lj~R]

Got my car dynoed today (tuned the boost controller)and it managed to get 228.1hp@5000rpm on wheel 14psi boost. Was wonder why my dyno result reading quite low in compare with my mate's 1994 s14(JDM). He managed to get 243hp@wheel around 6000rpm@14psi boot.BTW my car is nz new not sure if that is different to JDM model and we dynoed on the same place. I know air fuel ratio loosk very lean after 4000rpm. Don't have any idea where the other 15 horses go .I guess there must be somthing wrong with my car?!
engine mod's I 've done
60mm throttle body
FMIC
trust intake
3inch front pipe
cat removed
walbro 255L fuel pump
hks silient hi power exhaust
Greddy profec b boost controller
stock bov (modified)
We have similar engine mods except he doesn't have 3inch front pipe and cat removed but he has greddy type r bov.

 

[mint]

hmm you have to bear in mind that a RR isnt great for getting readings mate, i mean if you went to 5 RR's in one day you wouldnt get the same results between 2 of them.

Also things for example air flow/ fuel etc, I bet if you had gone to another one it would have been fine, or another RR and you'd be asking where the extra 15hp has come from ^_^ lol. I wouldnt worry about it too much tbh mate.

Also depending on the age of the car you have to bear in mind its history? Wear over time etc etc will cause a drop in engine performance over the years.

 

[meddler]

Your air fuel ratio in the second pic looks a bit strange. It shouldn't get as low as 10. Looks like you car is really leaning out. Having it that lean would kill quite a few horses and maybe your engine in the long run. Maybe check your fuel filter. Might be time for a new one. Just a thought.

 

[kazamas15]

I personally believe the JDM spec is likely to pull out more HP compared to NZ spec.

My friend's GT-T is a good example. We compared the acceleration of R33 (JDM) and R34 (NZ). The R34 really struggled to keep up with R33, but when he change to JDM spec (he got pissed of with the NZ spec and bought a JDM spec), it just managed to keep up with R33, probably just because R34 is still slightly heavier.

However, I notice that you have got FMIC, but no tuning on done on air fuel ratio. It?s likely that you will get a lower dyno result, because the a/f ratio is not tuned.

 

[japmadlad]

get it remapped :nod:

 

[Yakozan]

I'm running similar spec on my JDM and got about 241hp ATW with 11psi peak boost, running 98RON fuel.
Also on rollers.
Do you have bad tyres maybe?
If the car is spinning on the rollers it will show less power.
If you have good tyres then AFR is the only thing I can think of.

 

[lj~R]

Cheers for all the replays.

I got goodyear f1 eagle 245/40/17 on the rear and it shouldn't spin at all I supposed. I'd like to buy a power fc and it will worth money value if I'm planning to gain more power in future.But currently I think to get a APEXI SAFC is the next step what I have to do lor :nod: Actually, it's cheaper to buy and tuned.

 

[gunner93]

Seems your hp peak too soon. It should cont to peak up to 6,500rpm. Also AFR should come down gradually. JDms need to run abit rich at higher RPMs.

 

[kazamas15]

yeah the peak power happens around 5000rpm, that is rather low for s15.