Don Terrill’s Speed-Talk

Good news hopefully. Talked to him today and there is a bad plug. One of them is melted through the ceramic at the plug boot tip. Maybe result of a bad plug or boot coming loose. He is getting a new set of plugs now to repair it. So I hope the thing was arcing there and getting another plug gap, and...

For my car... approx. 3300 lb Camaro. 3.42 gears, 2,400 stall. Tires are 295/50/R15 California 2 season weather, with crappy 10% ethanol gasoline. Fuel does sit for a while as I drive the car a couple times a month. And for the above mentioned, not sure on the advertised specs...Had a lot of hotrods...

Don't remember my advertised specs as I almost never look at advertised. I'll have to dig up my cam card. Off hand by memory which might be right, I think intake was advertised at 294. This is a hyd. roller cam. Here is another thing to consider too. The more you push the limit, the more finicky tun...

Biggest thing is if it is heads or cam, he won't be able to do it without my help. The next semester is coming at the beginning of the year. So it is one of those crunch time builds/repairs

It was running till the trans linkage went. I installed a Pro Ratchet for its Powerglide which was a pain. The radiator and water pump went. The Rochester was trash even the boosters were chewed up. The HEI distributor would not advance or retard from some much rust...the shaft was toast. The altern...

-we used to find flat exhaust cam lobes, broken exhaust valve springs, badly bent or broken exhaust pushrods caused the popping back thru the intake.. -You might want to pull the valve covers and see if all the exhaust valves appear to moving up and down the same amount or if there's a broken sprin...

All worked fine with my engine. I gave him my distributor setup, wires, and we got new plugs. The only thing I can think of there is that my CD box pushed past a problem. He is inductive now. maybe there is an issue there??? Or worse yet, at the valve events. But I have to eliminate everything else ...

Everything rebuilt in the carby, cleaned etc. Even the check valve.

if its just at initial throttle tip in, very first thing i'd check is that little rubber umbrella seal for the accellerator pump. one little pin hole in those causes untold grief, and still visibly look like its getting good pump shot. Its definitely getting a crap load of accel pump shot as thrott...

No vacuum leaks, initial shot good. Thinking about having him get a Chevy points type cap and rotor from the parts house to keep costs down. It is an MSD ready to run with the points type system. I also told him to close the gap some. The above mentioned are easier fixes, but what I am more worried ...

My specs with 91 octane gas 11.25:1 SBC 400 234/244 @.050, 112 lobe 4 degrees advanced iron headed 64 cc chambers timing is at 20 initial, 34 total cranking compression is 210 all around...was 220 when originally built zero decked block with Fel Pro 1014 gasket if I remember right, but quench is goo...

And as far as timing, I did take that across the board to see if it could be an issue. 10 initial, tried, no vacuum advance, total timing shouldn't be in play as the problem isn't there, but bumped that around a few degrees. Also changed springs to see if the engine didn't like the mechanical curve....

Initial is the same without vacuum advance as he is connected to ported vacuum. Same with total as the can pulls timing out where it should...Also worth noting, the voltage is a very constant 14.3VDC everywhere as the engine is running.

Oh..and the carby set up very well via the mixture screws. The vacuum needle was very steady at 15" of vacuum. Which is lower than I expected, but the engine internals are unknown. But via the vacuum gauge everything looked good.

Visited my brother in law at Christmas. Didn't have much time to troubleshoot. He has a 307 Chevy that has a backfire through the carb if you barely lean into the throttle. If you rev the engine it is not there. Known specs... 307 Chevy camelhump heads unknown cam Holley 650 vacuum used MSD ready to...