So, first pull...not too great. Max HP ~200. I say oh great...what crap.

So since i havne't scanned my embarrasing dyno, i'll describe it as best I can.

Pre-VTEC (low cam), the car is making great power (actually the mx hp is at at vtec switchover...once VTEC switch-over comes...i get a short dip, then small climb in power, and then it just falls off...
best pull was ~225hp. needless to say, i was bummed.

Gotta open the head up...the car shop i've taken to want to check out the pins that push through the rockers to engage vtec (forgive me if I have this wrong).

We won't know jack until they open her up.

Any other theories from you guys/gals?

Tom

 

225 with a turbo?

 

with a problematic turbo

It really should hit about 270-280 if we can figure out why it's not making power in VTEC land. The turbo itself is working properly.

 

I WAS BUMMED too when i first dynoed my car and it was a horrible street tune on 7lbs and it did 247 i almost started crying but then it got cleared up wooohhooooo

 

Sounds like you have an exhaust restriction. Usually the problem is somewhere in the exhaust itself. Either downpipe, cat converter (if you're still running one), or the exhaust piping/muffler.

More rarely, its a problem with turbo choice, usually too small an exhaust side, or too small an A/R on the exhaust side.

The problem occurs because of excessive backpressure combining with the high overlap of the high rpm VTEC lobes to push exhaust gasses back into the chamber (or not allow their efficient exit).

We've seen this on a number of VTEC Hondas, and freeing up the exhaust fixes 90% of them. Replacing the exhaust side of the turbo is usually the fix for the remainder.

SC

 

what size turbo are you running?

 

Oh yeah, sorry, i forgot to mention, we completely disconnected the cat to rule that out. it did give us another 20 hp or so, but the power curve is still really jacked up.

I have autologic pick the turbo for me. I believe it's a sc61. not 100% sure, but i think it's that. a hybrid.

~7K rpms
_
/ \
VTEC / \
_ / \ <- before 9K
/ \ /
/
/
/

closest I can come to drawing it without scanning it in (which I will do). There is a drop off in power when it shoudl climb to about 8000rpm or a little after, and then drop off just a tad...not like what is on my dyno sheet.

:/

 

ok, the dyno graph didn't turn out right...

 

 

How's your oil pressure? I remember reading that someone else was having similar problems with VTEC not engaging because the oil feed to the turbo caused enough of a drop in pressure to stop engagement. Who's working on the car? Autologic?