Any advice, blacktop 20v 7age wont rev past 6500rpm

[JinxD]

hey guys having some problems, maybe someone else has had this problem before?

engine setup:

7age 20V blacktop head. recut cam sprocket etc. stock AE111 ecu running COP's
OEM coil and igniter connected, speed sensor connected. O2 connected, sta wire connected etc. Ecu throwing no error codes.

The problem:

car starts runs and idles fine, when revving the car on partial throttle it winds out to 8400rpmish no problems.
when you put the car on wide open throttle it gets stuck at 6500rpm like its hitting a brick wall.

things ive checked.

changed over fuel pump, changed injectors, ignition timing is good etc im thinking it has something to do with the cop's
does anyone have any ideas, on what could be causing this? i know there was a thread on Club4age but since they had a crash i cant get to it.
thanks guys

[fantapants]

have heard the knock sensor in the blacktop ecu is VERY sensitive.... as it only happens on full throttle, maybe its being a pmsing chickieboo?

[JinxD]

Well it's worth a shot ill keep you posted

[ahstwin]

Does it stay steady at that rpm or does it rev hunt?

[Matt]

i'd be ensuring the vvt is working correctly... It'll struggle to rev out without it working.

But there was a thread on this not that long ago here where the timing needed to be wound up cos of the cop setup...

Also from my own experience I've seen a dud alternator give similar symptoms too

[JinxD]

i can have go with the timing like mentioned in that thread and report back but it will stay at that rpm but it really has a heart attack like you are sitting it on full limiter
thanks for the quick replies so far guys

[Matt]

Would most likely be the timing...

[timbo]

It can rev rev free all day, it's when it's under load that the problem occurs. Timing would be the first thing to check, the timing may be retarding when it should be advancing. The TPS can be the cause of the problem. Check the base timing whilst revving the engine and watch where the timing mark travels; left for advance and right for retard.

[JinxD]

had a play with it tonight.
turns out that the dizzy was getting turned as the motor rev's so reset the timing to 10btdc tightened everything up and it seems fine.
when i checked it was set to 0deg btdc seems the cover was getting caught on the heater outlets due to the block being taller from the 7A

[Matt]

Glad you got it sorted... I've got a fresh 7a sitting on a stand in my shed waiting to go into my daily... Is stock 7a rods, silvertop pistons and head, but blacktop ecu.