1973 IH Scout II 345, 727, tri y headers d300 twin stick, msd 6a and coil, pertronix, 10 degrees timing, jet stage 2 quadrajet, IH only rpt intake, autolite 85's at .040, 268h comp cam, 37's 4.56 gears, 3/4 ton IH truck axles SOA with 4 wheel disc. Idle rpm at 750 in gear. That is as low as I can set it without it dying. Nice lope from the cam.
Truck runs Rich to the smell. 10 degrees timing. Gas/no ethanol, 4 psi from a mechanical stock pump.
9 degrees of steady vacuum no matter my tuning on the mixture screws. The quad screws are out 3 and the apt is out 5 from the bottom. It will lock up the 37's brake wise.
My question: do you think 9" of vacuum is close with the 268h cam or do I have a vacuum leak?
I have sprayed carb cleaner with no increase in idle rpm.
When I installed the intake I used the metal gaskets and red hi tack spray. Not copper. I hear that May be bad. I May have used black rtv on the intake threads, but I can't remember. I have rpt intake 038.
Help me figure out my tuning and advise as to thoughts on the vacuum of 9" with a cam. Motor cranks and runs great, just smells a little Rich. Might benefit from a good long trip to burn off some oil and I could have some pin hole exhaust leaks in the pipes. New dual setup coming soon.
Thanks.
Update!!!!!
I found two huge vacuum leaks. I thought the choke stove bolts locations were bottomed out threads. They dump right into an intake runners. :facepalm: thanks to my buddy levi for catching it!
Truck runs Rich to the smell. 10 degrees timing. Gas/no ethanol, 4 psi from a mechanical stock pump.
9 degrees of steady vacuum no matter my tuning on the mixture screws. The quad screws are out 3 and the apt is out 5 from the bottom. It will lock up the 37's brake wise.
My question: do you think 9" of vacuum is close with the 268h cam or do I have a vacuum leak?
I have sprayed carb cleaner with no increase in idle rpm.
When I installed the intake I used the metal gaskets and red hi tack spray. Not copper. I hear that May be bad. I May have used black rtv on the intake threads, but I can't remember. I have rpt intake 038.
Help me figure out my tuning and advise as to thoughts on the vacuum of 9" with a cam. Motor cranks and runs great, just smells a little Rich. Might benefit from a good long trip to burn off some oil and I could have some pin hole exhaust leaks in the pipes. New dual setup coming soon.
Thanks.
Update!!!!!
I found two huge vacuum leaks. I thought the choke stove bolts locations were bottomed out threads. They dump right into an intake runners. :facepalm: thanks to my buddy levi for catching it!
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