i have a b18c1: 9:1 cp, b16a1 cams, skunk2 intake manifold, 2.5" intercooler piping, homemade log manifold (see in my build thread), garrett t3/t4 60 trim (.60 cold side .63 hot side). on the dyno at 8psi it made 197whp so we thought vtec wasnt working. i checked vtec by reving to ~3000 rpm and touching the solinoid to 12v. there was a definate change in tone so i figured that it is working mechanicaly. i then tested output from the ecu with a test light, the light came on. so i believe that vtec is working. from there we started to look at the dyno graphs at 6000rpm it made 165 torque after that torque fell on its face. just to see what would happen we raised the boost to 13psi, it made 206hp and ~175 torque that still fell on its face. even if i wasnt engageing vtec, wouldnt the power have gone up still? it seems like i am hitting a brick wall at 200whp. my tuner also said that vtec maps only wanted a little more fuel than the low cam. do you think my manifold could cause this low of hp. we replaced the distributer and turbo. we checked for boost leaks, clogged intercooler, anything we could think of. the torque seems like its not to far off but the hp is way low.


Modified by dbiker207 at 11:51 PM 10/23/2007

 

how is ur wastegate routed? do u have a dump tube? if the wastegate is dump n anywhere near the turbo inlet thats the problem. post up a dyno graph.

 

not sure what kind of dyno you are on... but I know most people replace b16a cams with gsr/itr or more aggresive profiles.

is your timing correct?
timing belt installed correct (not off a tooth?)
is your dump dumping right by the intake?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted k20 &raquo;</TD></TR><TR><TD CLASS="quote">how is ur wastegate routed? do u have a dump tube? if the wastegate is dump n anywhere near the turbo inlet thats the problem. post up a dyno graph.</TD></TR></TABLE>

yes i have a dump tube, i welded a 45 degree on to the end pointed away from the turbo inlet

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by markaria &raquo;</TD></TR><TR><TD CLASS="quote">not sure what kind of dyno you are on... but I know most people replace b16a cams with gsr/itr or more aggresive profiles.

is your timing correct?
timing belt installed correct (not off a tooth?)
is your dump dumping right by the intake?</TD></TR></TABLE>

timing belt was checked 3 times by 3 people

base ignition timing 16 degrees

 

i have a 3 inch downpipe and 2.5 inch catback with no cat

 

post up the dyno graph. what r u tuning the car with? is the dumptube routed under the oilpan? even if it has a 45 degree elbow and its dump n into the engine bay area, that could contaminate the oxygen

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted k20 &raquo;</TD></TR><TR><TD CLASS="quote">post up the dyno graph. what r u tuning the car with? is the dumptube routed under the oilpan? even if it has a 45 degree elbow and its dump n into the engine bay area, that could contaminate the oxygen</TD></TR></TABLE>

tuning with neptune, dumptube isnt under the oil pan, but my tuner said he has had alot of cars with the dumptube closer to the turbo than mine.

 

hows the compression on the motor? my car was doing something similar and it turned out i was runnin on 3 1/2 cylinders.... run a leakdown and compression test, thats what i would do first. the manifold will not cause that much of a restriction that you would be down that much horse. how far are you revin the motor on the dyno? if its not goin into the high cam profile your not gonna make any more power. with the vtec engagement turned off on my car for ***** and giggles on the dyno (we were also trouble shooting) my car only made around 220ish hp. im not convinced your vtec is engaging at this point

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BUILT4BOOST &raquo;</TD></TR><TR><TD CLASS="quote">hows the compression on the motor? my car was doing something similar and it turned out i was runnin on 3 1/2 cylinders.... run a leakdown and compression test, thats what i would do first. the manifold will not cause that much of a restriction that you would be down that much horse. how far are you revin the motor on the dyno? if its not goin into the high cam profile your not gonna make any more power. with the vtec engagement turned off on my car for ***** and giggles on the dyno (we were also trouble shooting) my car only made around 220ish hp. im not convinced your vtec is engaging at this point</TD></TR></TABLE>
how did you figure out that vtec wasnt working on your car? the only reason i thought it was working is because the tone changed when i touched off the solinoid and even at a higher boost level it didnt really make anymore power.

i did a compression check before i went to the dyno it was:180,188,185,190. this was after the initial start up, i started it up and tuned the idle a/f, let it get up to operating temp, shut it off and did the compression check so it was done before the rings had seated

 

we need dyno sheets

 

vtec is at 5300

 

you're running 11:1 AFs, when you should be in the 12:1 range and it doesnt appear as though VTEC is engaging. You can see the turbo spool, but quickly die off because there is no high cam or fuel to support it

the spool on that turbo sucks too and it shouldnt with a log...IMO find a new tuner

 

you think it would be a bad idea to unplug the vtec solinoid and go for a drive to see if it feel any different?

 

These weren't the final charts, and the afr was cleaned up more on the streets, but you get the picture. Like dom said, we pretty much tried everything to make power, probably a total of 7 hours on the dyno playing with diffrent maps, diffrent timing values, diffrent afr. We moved vtec all over and witnessed changes in the graph and afr. Checked base timing 3 times, cam timing, etc. Checked the vtec soleniod with a test lamp, checked the intercooler for clogs, boost leaks etc. Even with cars that i have tuned on the dyno that didn't go into vtec we always have seen an increase in hp with increase in boost (up to a point).

Here is the dyno vs. another gsr, only thing diffrent was exhaust manifold, you can see at 4500 it hits a brick wall, and it did that no matter what.

 

Not to mention everyone that saw the inside of the manifold insisted that it was the problem and the area was to small that was feeding to the turbo, through the ecu and logs vtec it was switching over as well

 

im starting to think that vtec isnt working properly. when we moved vtec around and saw the change in the graph, couldnt that have been because the maps were changing over but the cams werent? the only reason i say this is because austins dyno layed over mine there is a increase in torque at 4500 (where austin says vtec is)
on mine at 5300 there is no increase in torque.

I just want to say that the guys at Synapse have been very helpful and gave me a break so i didnt go broke paying for 2 days of tuning.

 

a really nasty log manifold could cause those problems, but there has to be a compounding variable because even after the spool, the power quickly dies off...

Mike, i trust you guys for tuning and recant my previous statements about finding a new tuner. Hopefully we'll get this all sorted out soon!

 

The only way its possible its not going into to vtec is a mechanical problem, we checked and made sure oil pressure was there, i for a while myself thought it wasn't engaging but you could hear a tone change @ engagment and I believe the owner himself touched the soleniod when it was running and watched/heard it engage.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike@synapse motorsport &raquo;</TD></TR><TR><TD CLASS="quote">The only way its possible its not going into to vtec is a mechanical problem, we checked and made sure oil pressure was there, i for a while myself thought it wasn't engaging but you could hear a tone change @ engagment and I believe the owner himself touched the soleniod when it was running and watched/heard it engage.</TD></TR></TABLE>

i was gonna say if you didnt actually hear it engaging then it could be a clogged screen on the solenoid. we had the same problem it was getting power at the right rpm but VTEC wasnt locking in so we piulled the solenoid and sure as **** it was filled with bearing material from the previously spun bearing in the motor.

 

U can buy my Synapse ramhorn manifold for 400 haha and youll be straight

 

I remember seeing a GSR that was having issues with the IAB? (secondary intake runners? I know what it is I just can't remember the name) and pretty much had the SAME results. Car fell flat on it's face because they weren't engaging.

Something to look into?

 

lets assume vtec isnt working, midrange tq still would have risen with the increase in boost. 8psi-&gt;14psi would have made a ton of tq.

on my personal car, I've made about 300whp on the low cam with a moderate amount of boost. ie 10-11psi with my 35r midrange was good but top end was nowhere to be found. i wouldnt expect the same power, but the same characteristic would exist, good midrange, no top end.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SovXietday &raquo;</TD></TR><TR><TD CLASS="quote">I remember seeing a GSR that was having issues with the IAB? (secondary intake runners? I know what it is I just can't remember the name) and pretty much had the SAME results. Car fell flat on it's face because they weren't engaging.

Something to look into?</TD></TR></TABLE>

he has a skunk2 intake manifold no butterflys.

 

went for a drive tonight for the first time on dry pavement. vtec is definatly working 100%. me and my friend coujld hear and feel vtec engaging at 5300. it was pretty prominate in 4th gear. i think the reason i doubted it was, it would spin and go through the revs so fast that i couldnt hear it, and the tires were spinning and i couldnt feel the gain.

 

do a leak down test.....i had a similar problem with a car that had a bent valve(s). kicked my *** for a while.

 

a bent valve would have showen up in the compression check i did.