I posted before on a simular topic but didn't get any answers.I have the crower 63403 vtec cams, springs, retainers. My question is in your experience what are the optimal fuel pressure settings, cam timing for intake and exhaust, and vtec crossover? I have a stock fpr on there now. When the car goes into vtec the power seams to just die. I have set the vtec to 6000, 6200, 6500, the power loss seams to start with the vtec crossover.

Thanks
Derek

 

I don't have any experience with those cams unfortunately, but if vtec changeover is a problem do one dyno pull with the vtec change over at 500 rpm, then one at 9000 rpm, then put the two torque curves together and see where you'll get the most area under the curve.

 

check out this site
timing at 19 deg
http://crower.com/cat/import/h...3.jpg

 

I wish there was dyno around here local. I just moved the vtec down to 5000 rpms and I still get the same symtoms. the power band just dies. does anyone know what psi the fuel is on a gsr with stock fpr? I need to get an aftermarket one.

 

38 psi at idle
that is running stock injectors
you should maybe consider prelude 290cc injectors

 

I guess my question is would a fpr fix my problem?

 

another question is my car idles at 1500 rpms when fully warmed up, could there be a timing issue causing the car to run like crap when in vtec? I dont know the symtoms of a motor with timing off.

 

You're getting lean at vtec. Get Hondata or at least a Vafc and have it properly dynod. Crower will tell you to set your x-over around 6300. I find 6k to be best on my setup. I'm running 42psi pressure with 410cc injectors hondata tuned. The gears are at +2.75I and -.5E, that setting seems to give me the best midrange power. Optimal settings for your car could be very different.

 

udate: me and my friend found out something funny while installing my fpr and gauge. I know that vtec is tempromental(sp?) but will the engine go into vtec sitting still in neutral. The reason why I ask is before we were fiddling with the fpr I got my friend to listen to the engine while I reved it up. when the car switched it to the vtec cam the car would seam like it would miss or like it was some kind if rev limiter. I installed a brand new dist about a month ago.

thanks

 

im assuming that you are using a vafc

that sounds like fuel cut to me ...
also the problem with changing vtec cross over is due to the ecu changing fuel and timming maps at a set rpm...when you change it the ecu still changes the same so when you set it higher (witch you should be) you have to correct the difference in fuel from afc to ecu you hit a dead spot of lopts of fuel and not enough air...or in my case(i lowered vtec)and get lots of air no fuel..and no power

this can only be cured so much on a dyno but still there is no way to fix the timming when changing vtec...

best bet is to get it on a dyno with air fuel read out and see how it looks

 

I'm using a feilds vtec controller with fuel setting at 0. I have set vtec range 4500-6500 rpms same thing happens when it goes into vtec. there is no difference or change what so ever. my fpr is set to 50 psi on stock injectors. i have no access to a dyno around here, so that sucks.

 

update: Its amazing how much power you can make by swapping out a 90 crx hf 1 inch piping for custom 2.5 inch piping and freeflow muffler. it seems that it wasnt fuel cut but the exhaust trying to get out. the car went from dieing when it went into to vtec to breaking traction from 4000 rpms and up in 1st. the car runs 100 times better