I had a very nice conversation with Gus this afternoon on the phone.
He says, and he is right, that even if the exhaust manifold isnt big enough, the engine wouldnt detonate at higher advanced degrees on high revs !
He believes that the problem is either with too much compression, OR with my cams no been timed the way they should !
You see what I did when closing the engine with the fast road cams, was use the standard cam pulleys - as suggested from the company who sold them to me.
I put the timing of the engine EXACTLY on the marks, as I would do with a standard engine with standard cams and pistons !
The only way to make sure that didnt happen, is to measure the timing of the cams with a gauge instead of the marks of the cam pulleys.
This means I need to drop the engine to have it checked as there isnt any room in the engine bay to do this test.
SO ! I'll wait for the powerflex bushes to arrive, probably by the end of this week or beginning of next week, order a pair of adjustable vernier pulleys for good measure, cross my fingers and hope for the best !
If the timing is exactly right even with the gauge measurement, that would mean that I will need to brake down the engine and skim the pistons. I hope it doesnt come to that !
Gus, thank you very much for all your help mate
I just hope after I do this I can come back and tell you that I gained the desired 25 to 30 bhp