Running it to 7000 rpm's is not something I insist to do, in fact I choose this mild cam to keep the rpm's down, but that does not change the fact that with these big heads it does pull very easily to 7000 rpm's and does not seem to fall on it's face at all. Changing heads is not an option for me now, but I might consider that option later, these heads do come off my racing engine and will be put on that engine before next racing season. These heads do have 64cc chambers, here in Iceland we don't have a flow bench, so we are not able to go to some major modification on these heads. The main reason I choose to use these heads are because I think it's better to use these well flowing aluminum heads, even though they are This big for moderate 350 CID engine, rather than using some poor flowing small valve Smog heads with bad combustion carachteristics and big bath tub chambers.
The crank is cast piece. But I don't quite think that's the main issue here, in fact there are local racer's here in Iceland that are running a nitrousd 8000+ rpm 355 CID engine in the 5.60's in 1/8 mile with cast crank, and lightweight rotating assembly. But maybe their pushing it to the limit..!
In fact I'm do already have a sfi approved balancer that I'm going to use and the block deck is pretty good, last time this engine was together I did use fel pro #1094 head gaskets that do measure 0.015" thick without problems.
You say that with flat top pistons this engine might be around 10:1 compression ratio, depending on heads and head gasket, deck height etc. this engine must run on 91 oct gas. But with this moderate size cam and aluminum heads that's maybe no issue with 10:1 comp ratio ?
I'm dead on that the only reason I had bearing issues is because these stock rod bolts didn't held up at these rpm's. But since we are started to talk about bearings, what kind of bearings do you advice me to use in this mild build ?
Best regards from Iceland.