well in the quest for more power i switched out my itr cams for skunk2 tuner stage 1's

on old set up with 2.5"exhaust, s2 im, and itr cams i put down 425 @15psi, went to get retuned today and at 15psi i put down 350whp

new parts are victor x, 3" exhaust, and s2 t1 cams

vtec works when set low, but it just doesnt seem to carry power like it should, it starts dying around 7k even with the boost creaping a couple psi

checked the solenoid and it activates, how else would i be able to tell where the problem was, it worked before perfectly but doesnt seem to be working now, if we engaged vtec 1000 rpm later it would have a little bit of power difference but no noticable/audible engagement

 

during the cam swap did you lose the o-ring or dowel in the middle cap??

 

take the vtec off the motor and check the screen.. it might be clogged or what he said..^^

 

already checked the middle dowel with the o-ring and they were fine

 

You have to move your vtec setting higher in the RPM to get the power of the the cams they have a slight more lobe in them.

 

kill yourself, please.

 

I highly doubt thats his issue, this is not the first car his tuner has touched......

 

what would happen if its missing.

 

What turbo manifold do you have and also how big is your exhaust? Did you guys set the timing belt right... checked timing with a timing light?

 

that's one of the first things the tuner will check, is the timing. Highly doubt that is the problem. Moving forward with a dyno when the timing is off is pointless.

What is your oil pressure? If the solenoid is engaging then it probably wouldn't be the solenoid wiring. Double check the screen like someone said.

 

possible low oiling potential

 

He has a full race GT kit. It is a .82 a/r 35R.

The timing is set correctly, the dizzy is in the middle of the end cap so it is very close.

I did not recheck the mechanical timing yet, but at some point this weekend we are going to do a leak down. As he did have the tensioner come loose and the belt slipped about a week ago.

The compression checked out just fine across the board so at this point I am pretty stumped on it.

 

UMMMM What are the Lobe centers guys????????

 

what does lobe centers have to do with vtec not mechanically engaging?

i will have john or derek post up the comparison chart of the power now and power before

with my mods i should be able to make power to 9k all day long and its not carrying past 7000

i am just looking for some ideas

we set it really early and heard an audible crossover, but when set higher it will not engage

 

why dont you forget the ecu. take a wire from a 12v source, then apply it to the vtec sol when the engine is at high rpm.

what engine management are you using ?

 

A friend recently had this problem, although a different scenario, he had random vtec engagement. his head was missing the pins that hold the rocker arm rods in place. (although this doesnt sound like your issue)

 

another thing is.... perhaps you dont "hear" or "feel" vtec enguage because your cam timing is jacked, the overlap would only get worse with RPM.

 

going to check mechanical timing tomorrow

using s300, checked the solenoid to made sure it clicked and it did

 

Brian, did you check valve lash when you installed the cams?

 

when you figure it out let me know. ive been having similar problems.

 

yes installed cams and set lash to 7 for intake and 8 for exhaust

i really think it has to do with oiling system or something, if it was cam timing i doubt i would make 390 whp with it , and the fact that when set really low it engages

 

Time to get an oil pressure gauge. If it is a failing oil pump at least you can diagnose it before it wrecks your bottom end.

 

So it does not engage at higher rpm?

in for results when the problem is fixed!

 

Yeah. I'm thinking it's an oiling issue and we also had the issue with the dyno. Made for a shitty day.

Reason I asked about the valve lash is perhaps the cam key was cut ever so slightly off, allowing the cam gear timing to be inline with the crank, but the physical camshaft lobes were off by how ever much.

 

that wouldnt explain no audible vtec crossover


checked mechanical timing today and it was dead on (of course )

checked the main o-ring again under the middle cam cap and it was ok

checked the 2 o-rings at the cam gear end and they were good

tore apart the vtec solenoid and screens were clean and the plunger was working perfectly

put positive wire to the vtec solenoid at idle and made an audible difference in idle

drove it and idk wether its the cold weather or its working but its get pretty lean after 4,000ish (couldnt really tell because it spins through 3rd gear, and 4th gear was on highway and didnt want to chance running it lean)

plan on putting a mechanical oil pressure gauge on the front vtec oil port tomorrow and see what pressure i get at 5,000rpm

if all else fails i will buy a new oil pump and install that bitch (dont see why changing cams would make the oil pump go out though!!!!! )