High rpm problems

[mikeylighter]

Picked up a 2g yesterday, has a 6 bolt bottom end with 2g head. Once I hit about 4500rpms the car looses a very noticable amount of power, and feels very rough. I was told it was due to the cars CAS, and that I needed the black top one. And after I run it for a while it will suddenly start running on 3, but if i turn the key off and on real quick, it will fix it. The PO put an hks bov on it, so its not recirculating right now. I know that causes problems with the engine dying after pressing in the clutch, but can it also cause high rpm problems? Before I sink the money and time into tracking down a black top, I wanted to make sure that it is the issue.

 

[954g63gst]

that happend to me when i installed a 16g turbo as my first mod. everytime i hit 3500rpm the car felt like it self governed or lost power did you upgrade your turbo or did he

 

[mikeylighter]

it has the t25 still in it

 

[GSTurbo1]

your spark is probably blowing out, try putting new ngk copper plugs in gapped at about .030. I had the same problem and just stepped down to a colder plug and had to close the gap a little bit.

 

[Afizzle]

try basic maintenance before replacing anythign expensive.

BOOST LEAK TEST, plugs & wires, compression test, and a leak down test. Fix all boost leaks and run these other tests and report back if the problem is still there.

http://www.dsmtuners.com/forums/articles-parts-fabrication/386650-how-build-boost-leak-tester.html

http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

http://www.dsmtuners.com/forums/articles-420a-specific/258957-compression-test.html

 

[Ace_gst]

Are you running the 2g head, if so you maybe throwing the random miss fire code. I would stop where I was a reset the battery (pull neg off battery for a few minutes). That would cure it for me.

I was running a black top as well, still have it if you need it, and I never had high idle. When the ecu was throwing code it would stall and almost have a idle surge but more cammy feel to it.

Sorry I see you have a 2g head. Check your codes most likely random miss fire which needs to be tuned out.