so i got this ls/vtec in a 94 cx hatch
and it doesn't rev pas 4.5k when you give it alot of gas
but if u baby it it does go past 4.5k
i took it to the mechanic and he told me that it was becuase of
low oil pressure but everyone else says thats not the problem
i was wondering if any of you guys could help me out?
i bought the ls/vtec kit from inlinePRO
the head is a 2000 b16

 

Describe what happens when you reach 4.5k. Does the rpm ever bounce? Does it missfire at all? Is there any sluggishness you can notice? Post any mods. The most likely causes of your problem are timing, a restriction in air/fuel delivery or a malfunctioning sensor.

 

yea it sounds like misfires
do you think it could be the distributor thats gone bad then?

 

It's often difficult to diagnose problems that only occur at high rpm. You can check it with a timing light to see if the sparks are coming at the correct time, most importantly at max rpm. You can check or replace the air filter to see if you just can't get enough air to support high rpm. You can also test the fuel pressure. The sensors in the dizzy can be checked by testing the resistance of each. It would be unusual for the distributor sensors to only have problems at high rpm but not completely unheard of.

 

ok i will check the fuel pressure

 

Check it with both the regulator vacuum hose attached and with it disconnected. The proper fuel pressure at idle depends on your setup since it's a custom motor. With the regulator hose attached, you should see at least 30-38psi. R-type fuel systems run at about 38-45psi. With the hose disconnected, max fuel pressure should be about ten psi higher than with the regulator hose attached. A restriction in the system should create higher pressure and decreased flow. Low pressure means either a leak or a bad fuel pump. If the air and fuel systems are fine and you have no other problems at lower RPMs, it would have to be the timing, which could mean the distributor as you suspected. GL