OK, guys. I'm posting this here because I know you guys are very helpful. Its not re: my 69 Z/28, but rather my 66 Corvette Roadster.

I recently droped in a fresh LS6 with a reasonable amount of mods. The motor has been running great, just need to open up the exhaust as it is constricting the power.

Anyway, I was road racing it at Summit Point yesterday...first session was great, the second session it began to backfire a bit when I would come off of the throttle. I very gradually began to feel a reduction in power, albeit slight. I also began to hear a bit of a poping noise out of the exhaust...especially the drivers side. The timing checked out ok at 18 degrees at idle. It began to feel progressively worse (loss of power) and on my way home it finally shut off. I had to get towed home. When it shut off, it was like a turned the ignition off. The motor has no strange noises, etc.

I took the plugs out to have a look, they all looked fine. The new MSD distributer looked fine, no cracks. The new MSD looks fine (whatever thats worth). Took both valve covers off to see if maybe a spring was cracked/broken etc., all looked fine. this evening, I took the #1 spark plug out to look for a spark...no spark.

I'll take the MSD coil, which is older than dirt, to Track Auto to test tomorrow. I the meantime, any suggestions as to where else I should look?

[This message has been edited by Rafael Fagundo (edited 10-31-2000).]

[This message has been edited by Rafael Fagundo (edited 11-01-2000).]

perhaps it could be your alternator.. if it was running off the battery for a while the spark would get weaker and weaker as the battery drained, IE the popping noise and the lose of power and then finally when the battery got too weak it will shut off and quit running. Check the alternator and the voltage regulator, hope that helps

Tim

The battery seems strong. It cranks the motor real well. I just replaced the coil, but no difference. The car won't start. Check the new MSD, it seems fine. Now I'm getting little explosions out of the carb. Anyone else?

if you're getting little explosions out of the carb it means you are getting spark at least.

Sounds like you could have a valve problem. Do a compression check and see what's going on. Little back fires through the carb could mean a hung valve or valves. Depending on how bad it is I would think it would run anyway though, but with a bad miss. A compression check will tell you alot and eliminate any Mechanical engine problems. Then you can move on to other areas.

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Rafael,

Check and see if the dist is still on #1 when the timing mark is on zero. If its firing once in a while but poofing out the carb, it sounds like it's out of time. Check the dist gear, if you are running a roller cam you need a bronze gear, or if you are running to much oil pressure, it will get the dist gear.

Also check all the wiring on the MSD stuff, be sure the main hot, and ground are in good shape. I don't have the # here at home but MSD has a good tech line that can take you through some test to tell if it is the MSD stuff.

Check all the MSD wiring, and the dist gear first and then call MSD.

Larry

Maybe as simple as you didn;t have the distributor locked down enough to withstand a nice whippin' at the track.

Check timing. Betchya it's off.

Sounds like a dynamite ride!

Well, guys...the good is I found the problem. The bad news?...its a pretty good size problem. Turns out, half of the gears on the distributer have been sheered off. It appears the CAM I have, a Crane CAM, "allows" for the use of a steel vs. alloy gear on the distributer. Well, for what ever reason, it took several teeth off, thus causing the mis-firing and ultimately, the shut off.

I took the distributer back to the engine builder who quickly recognized this was a manufacturer issue. So far, he has agreed to shield me from any costs for repair. Good thing, as I just spent and on-Godly amount of money on the new motor.

Thanks to all for the feedback!

[This message has been edited by Rafael Fagundo (edited 11-02-2000).]