Help- Built engine makes less power than before (dyno graph)

[andyman97]

If that was the case, it's not the norm.

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[dopes6070]

Well its not the norm I think because i modded the stock fpr LOL. and most people arent willing to do that type of thing.

[emjay]

what happens if u don't go returnline and are going for big power and just tune with 750cc and kpro ? i know pressure can increase ... but if it hasn't already ..it won't randomly would it?

[dopes6070]

I believe the stock fuel pressure is 43 psi so if you are forcing 15 psi into the intake manifold the boost works against the fuel pressure because remember the pump has to push fuel through the injectors and into the manifold to go with the boost. So you really only have 28 psi of fuel pressure which isnt nearly enouph. thats why everyone uses a 1:1 reglator which would bring it to 58 psi under boost. I just eliminated having to run a return line. I just needed a boost ref line going to the tank which I ran through my interior so it was hidden.

[tfnaaf]

well for all practical purposes the leaner the more HP he will make. ASSuming the tuner wasnt letting it detonate while he tuned it. It just seems like something else is wrong. If i were to guess timing may be off(cam or ignition)???? I guess my first question is what all was changed during the rebuild other than injectors and pistons? As for the must have standalone argument ehhh ... save that for a rainy day....... As far as the rising rate FPR it is true they are the way to go in most cases. In my case i tuned mine @ 7psi without the boost reference at all. Mine in fact is capped with out a vacuum line hooked up. Any fuel management is only as good as the person setting it up. Or in my case only as good as the amount of time spent setting it up.

[02fpcivic]

To a point lean is mean(and very dangerous), until you have severe detonation, then the motor fights itself. Think about it, the pre-ignition is the reason why you bend/throw rods, hammer the bearings out, break ring lands, etc..

[tfnaaf]

Originally Posted by 02fpcivic

To a point lean is mean(and very dangerous), until you have severe detonation, then the motor fights itself. Think about it, the pre-ignition is the reason why you bend/throw rods, hammer the bearings out, break ring lands, etc..

true, but like i said assuming he wasnt getting any detonation.

[02fpcivic]

Well who knows what this tuner is doing, hehe. Most of the places Ive been to have no idea about tuning obd2 piggy-back systems and the ones that do want nothing to do with them at boost levels this high. I think going k pro tuned at a hondata certified shop would probably cure this situation. I'd go through the car thoroughly before doing so to make sure everything was up to par.

[andyman97]

Originally Posted by 02fpcivic

Well who knows what this tuner is doing, hehe. Most of the places Ive been to have no idea about tuning obd2 piggy-back systems and the ones that do want nothing to do with them at boost levels this high. I think going k pro tuned at a hondata certified shop would probably cure this situation. I'd go through the car thoroughly before doing so to make sure everything was up to par.

Now if only people would listen...

[drunkenmagnum]

Well I am pretty sure something else is the issue here (the A/F is fine). I haven’t been driving the car lately and have been keeping an eye on the stats just to monitor that nothing is out of line. Next month I want to schedule time with a different tuner just to see what we might be able to do differently and get some input on this from another source and see what he says about the fuel problem or if there is one.

IT just seems to me that with those injectors, even with the stock fuel pump, that i should be able to put down no less than 200whp.

The car itself has been running great - minus any respectable power.

[emjay]

Originally Posted by andyman97

Now if only people would listen...

i listen i listen i won't do it unless i do it right

[drunkenmagnum]

My installer said the SRT-4 injectors went in without a issue but everyone else has had to mod there clips it seems to make them work. is it possible they could have been installed incorrectly or might i need a resistor box?

Dont think this is an issue, just throwing it out there.

[speedfoos]

No, SRT-4 injectors are high impedance just like the stock D17 and RSX ones, so you don't need a resistor box. The stock Honda clips will 'fit' the SRT-4 injectors, they just don't lock in firmly to make a secure connection. Basically they could pop off if you went over a big bump or something to jar the engine enough to pop a clip, but that doesn't sound like your issue.

[drunkenmagnum]

the way the boost drops off as the RPM and power increases, is that normal? havent found any real leaks but i want to make sure some is not creeping out.

[speedfoos]

Definitely sounds like you have a boost leak somewhere. Stock intake mani may be leaking. The rumor is that it's not guaranteed to much good over 12psi. 15psi could have caused a small breach and you now leak pressure from it. All you silcone joints are good? Using T-clamps or standard worm-clamps?

If your turbo has a pressure port on it, it may be worth hooking a boost gauge up to it and comparing the pressure drop between the compressor and what's registering at the IM. Might help pinpoint a leak.