When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
as referenced in the previous post, I think it's a separate issue from my idling problems.
[Setup: F20C, J's Racing exhaust, test pipe, ARC airbox, tuning on Emanage Ultimate]
My tuner attempted to lower the VTEC crossover point to 4000 rpm as after numerous runs, it was found he decided that was the point where the car makes the most power (having tried 5000 rpm and 5500 rpm). After sorting out the A/F, it was strapped to a dynopack and this was proven to make ard 5-6 whp between the rpm range of 5000-6000rpm. Area under graph was indeed more satisfactory.
However, after hard-running the car for a short 10mins, the car threw a VTEC Solenoid Code:22 CEL.
Switching back to crossover point of 5800rpm made it ok again.
What could be the reason?
What is the common consensus on VTEC crossover lowering?
Many thanks for your patience and understanding. Me and my friends spent 2 consecutive nights at the workshop till 1am in the morning troubleshooting but finding nothing.
How complicated/expensive/dangerous is it to lower the RPM level at which VTEC engages? I've got a stock 2005 S2k (8000rpm redline) with 22k miles on it and the car explodes off at 6k, but up till then, leaves some to be desired.
Originally Posted by RugRunner,Aug 10 2008, 12:11 AM
How complicated/expensive/dangerous is it to lower the RPM level at which VTEC engages? I've got a stock 2005 S2k (8000rpm redline) with 22k miles on it and the car explodes off at 6k, but up till then, leaves some to be desired.
I wouldn't mess with the vtec engagement on a stock S. You'll most likely loose top end power if you lower it all the way to 4k rpm....not to mention something worse.
I wouldn't mess with the vtec engagement on a stock S. You'll most likely loose top end power if you lower it all the way to 4k rpm....not to mention something worse.
You will not loose top end power it infact should remain the same.
Lowering vtec on a stock car will net a bit of power in the mid range but you are not taking full advantage of the larger profiles unless you are FI.
The larger lobs are not in the peek efficiency at lower RPMs unless you are forcing air into the motor.
In your case since it sound like you want to smooth out the transition lowering vetch 1k or 1.5k should do the trick. Just make sure your tuner appropriately adjusts fuel and ignition timing and that he does not have the lower vtec turn on unless say you are above 90% throttle any other TPS angle leave vtec stock.
I wouldn't mess with the vtec engagement on a stock S. You'll most likely loose top end power if you lower it all the way to 4k rpm....not to mention something worse.
not sure but aem tuners lower it to 4,200 and set the rev limit to 8500, thats how panducky tunned my friends ap2!
thanks for the jumper settings. you are right. it was that. *thumbs down to the emanage manual*
oh... got it retuned at vtec crossover pt of 5000rpm. found that though it makes more power at 4000rpm, (huge punchy low revs), but the trade off seems to be an incurable dip in power in the 6000rpm region.
at 5000rpm, the whole curve was tuned to be linear.
08-06-2008, 05:47 PM
[Emanage Ultimate] Lowering VTEC crossover @ 4K
