Hi my name is Joerg from Germany.
I have a 455 build new engine with Pertronics billet distributor III / hotter cam / Pro Comp alum.heads / Help needed, high compression
First at idle the rpm is stalling very high.
Timing was at to 14° initial and 36° advanced vacuum not connected. 4-6 vacuum
Runs like crap.
Than I put initial to 22° and 36° advanced, at idle way better and much more vacuum,
If i look on the FiTech handheld spark varies from 22 to 26° depends on stalling i guess distributor is spring loaded and if rpm are raising springs will open
compression is ok all above 10 / at 900 rpm about 10-11 vacuum.
No Intake leaks.
Now to my questions:
1. My O2 sensor is in the header collector after this I mounted only one muffler thats all, could this be a problem because Q2 sensor is getting to much fresh air from behind
2. Is it normal that this cam needs so much initial timing ?
I cant get support here in Germany because lack of knowledge.

Has anyone an idea ?

Regards Joerg



getting false readings because it get fresh air from behind ?

 

That cam should have 13-14” of vacuum no problem.
I’d set initial at 18 or so. What is your idle air/fuel target?