We took my turbo b16 hatch to the dyno and as soon as vtec would engage it would loose about 60whp and then begin to pick up power again. We took the car off the dyno and did a compression test and the numbers were 130-125 psi in the cylinders. Could the rings not be seated properly? Also would that effect the vtec the way it is affecting it?
My tuner said to change my rings but i dont want to change the rings and still have the same problem. I wanted to figure out the problem so when i take apart the motor i can fix it. BTW i checked all my bearings and they are brand new.

The motor is a b16a2 with
skunk2 IM
rev valvetrain
stock cams and gears
new oil and water pumps
acl bearings
eagle rods
je 9:1 81mm pistons
AC block guard
The turbo is a 50 trim 48 a/r exhaust 50 a/r compressor
2.5in down pipe and catless exhaust
no name big front mount intercooler.

I thought maybe the timing was off but its not. We checked it a few times and it is set at 16*

 

did you do a leak down on it? that will be able to tell you more

 

Is this a new build (motor)? Has the valvetrain been adjusted properly? What condition are your valve seals in? Have any copies of you dyno plot to post up? It could possibly be a tuning issue. Your compression is a bit on the low side, but it should still make power.

 

nah its not a tuner issue because ive tried 2 different tuners. BUt i can tell you that the air fuel is between 11 and 12 and as soon as vtec engages it goes crazy lean and the it comes back to 11 through 12. On 8 psi it made 184 whp. I have not done a leakdown test yet. Its a newly built motor has less than 5000 miles. I seated all the valves personally and i installed all the valvetrain. What would a leakdown tell me exactly? And do you think the rings arent seated correctly?

 

it has brand new valve seals. and gaskets.

 

it would tell you where its leaking at......

Sounds like the valves havent been adjusted like stated above..... when you finished your build did you adjust the valves?

 

ya the valve were adjusted. Then i switched from gsr cams back to b16a2 cams and i re adjusted them. The valvetrain makes no noise.

 

ttt

 

has anyone else had this problem?

 

why dont you take the advise and do a freaking leakdown test.... a leakdown test will tell you were your compression loss is going via rings intake valves exhuast valves head gasket etc etc... your car isnt going to get fixed over the internet all we can do is guide you...do the leakdown test and get back to us...

 

ok buddy im not doubting that a leakdown test wont prove the problem. Im just asking if anyone has had this problem before. RETARD!

 

I'm not too surprised at that number. The key is consistency cylinder to cylinder.

Also a poor breather system can hurt your ring seal.

EDIT: I re-read your post..I really don't see how low compression would cause a 60 whp drop upon vtec engagement. Were you looking at fuel pressure at the time by chance? maybe you have fuel issues, not compression issues? I think there's a different problem at hand.

 

what do you mean your not surprised with that number? THe cylinders are pretty much consistent. I dont have an oil catch can. So do you think the vtec problem is my rings?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92redhatch &raquo;</TD></TR><TR><TD CLASS="quote">THe cylinders are pretty much consistent. I dont have an oil catch can. </TD></TR></TABLE>

Bingo!

you probably don't have proper crank case ventilation, there for u blew out your rings

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Running925 &raquo;</TD></TR><TR><TD CLASS="quote">Bingo!

you probably don't have proper crank case ventilation, there for u blew out your rings</TD></TR></TABLE>

with compression that low this thing would be smoking, a lot.

 

no it only smokes on WOT(im guessing rings) and a little bit in the morning(valve seals). i ordered a leak down tester so as soon as i recieve it i will do the test.

 

Good job RETARD!