ok i'm trying to tune my friend's setup.. its a all out streetable race car if that makes since.. his setup:
AEM EMS
T3/T4 Drag kit
running 5 PSI so far..
wideband on the way
fully built h22a4 (rods, piston's.. cams, oversized valves, the works)
car.. 90 Accord.. gutted

here is the problem.. the car runs great without VTEC.. soon as it engages it feels like the car hit a revlimiter.. the A/F seems fine.. timing is ok.. i don't understand it.. i raised the VTEC to 9000.. so it won't come on.. and the car pulls great without it.. but he spent all this money on a h22a for VTEC.. so it'd be nice to have it.. any help is appricated..
i've already tired dumping fuel when VTEC hits.. retarding the timing.. leaning it out.. everything.. nothing seems to work.. the car car fine N/A and on nitirous.. its only done this on a turbo.. any one have any input?

 

the only thing i could think of is oil pressure. if its too low, vtec wont engage and it will feel like u hit the rev limiter.

check if the oil pressure sensor could be working? i dont know if the AEM bypasses that.

Oil pump going bad?

 

Try tuning out the cam overlap...that might be what's causing the problem...short term solution is to lower the VTEC point to about 5000

 

VTEC was origanaly at 5000, it didn't work there eirther. I'll check the oil pressure.. but the oil pump should be ok, all clearences checked out good 1000 miles ago. The sensor is working.. light comes on when engine is off, and goes off then its on.. so i know thats good

 

post your timing values, i bet i know what your problem is.

Better yet, send me your calibration file, and ill look it over

Mase@full-race.com

 

is this tuned on the dyno i hope?

 

My car is doing the same thing. As soon as i get near vtec my car wants to die. When the rpm gauge gets near 5000 it like hits a road block.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SMOOTH97LUDE &raquo;</TD></TR><TR><TD CLASS="quote">My car is doing the same thing. As soon as i get near vtec my car wants to die. When the rpm gauge gets near 5000 it like hits a road block. </TD></TR></TABLE>

what fuel management are you using?

 

I am using an V-AFC. When I had my car dyno tuned it never happen. at least i was not driving. So i guess it could have happened. The hesitation seems to happen in 1 and 2 gear.

 

what was the afr when they tuned it? and what boost levels?

 

mase i'm using an AEM base map timing.. the one that says.. 1000 turbo 310.
I only have modified fuel.. the timing is still set at base map.. any help you can give me would be helpful.
thanks..
PS i told my friend to switch his oil feed line.. he tapped off the oil pressure sending unit.. i think he is going to tap off somewhere else this time tho. we'll see how that works out

 

maybe your low on oil? That could cause the vtec not to engage

 

umm, no i'm always checking it thanks for the reply

 

try advancing the timing, h22's are larger bore and thus need more timing.

im willing to bet it will fix it

send me over your map, and ill make some changes

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">send me over your map, and ill make some changes</TD></TR></TABLE>

Yea... for 5 bucks every 10 minutes

 

hey mase, i'll send u the map soon as i get my laptop back, its in the car right now.. see what u can do.. thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GudeH23a &raquo;</TD></TR><TR><TD CLASS="quote">

Yea... for 5 bucks every 10 minutes </TD></TR></TABLE>

haha, no thats only for tools such as yourself