Hot Rod Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter · #1 ·
I recently got back into working on cars again. Its been a little over 25 years so please bare with me as I try to learn this again. Maybe pick up some new tricks of the trade.

I got a 1969 Camaro and it has a 406 SBC in it. Its a great motor and runs strong. Fairly aggressive cam. I just had some Aluminum heads put on it and bought a new Quick Fuel 750 Carb. I have it running and I feel like something just isn't right. I had an Edlebrock AV2 650 on it and it was set at 10 to 12 degrees advanced at idle. After installing the Quick Fuel 750 it seems to be idling best at 33 degrees at idle. Which I know is not good.

Hoping you can help give me some pointers on where to start. I plan to retard the timing back to 12 degrees and then work with the carburetor to try and bring it back to a good idle. But any tips and tricks you can share with me would be greatly appreciated. And if you need information please do not hesitate to ask. For example I am getting around 16 on the vacuum guage at idle with 33 advanced.

Thanks in advance. And I look forward to learning from this forum.
 

·
Registered
Joined
·
2,797 Posts
What compression do you have with the new heads? My SBC has about 9.4 compression and aluminum heads, and runs great with about 15-16/degrees base timing and 20 degrees more from mechanical advance by 2000 rpm. I have a fairly mild cam with 213/217 @ .050 and 112 LSA.
 

·
Race it, Don't rice it!
Joined
·
8,813 Posts
Timing is largely a function of Head chamber design and shape.
What heads?
Need more cam details too.
Likely, youll end up somewhere in the 15-18 initial and all in around 34/36. Get that squared and you can work on the carb tuning.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #4 ·
The compression will be around 10.5-1 with these heads. These are performance world heads. 196cc and 202/160 valves. The only thing I don't know much about is the cam shaft. It came with the original motor. All I can say is its quite lumpy and does give me some good power.

I set it to 12 degrees advanced at idle tonight and played around with the carb, I have 15 to 16 on the vacuum guage at idle. It max's out around 29 degrees total. I might try and advance it to 15 to 18 and see how it likes it.
 
1 - 5 of 5 Posts
Top