Ever since I've owned the car it has had an electric fuel pump back by the fuel tank. It and the blower fan draw current as soon as the key is in the accessory's position. I was wondering if a mechanical fuel pump would be better to allow the starter to have more juice on hot starts where I seem to have issues at times. I have 10.4 to 1 compression ratio and when the car is hot it seems to struggle to turn over. Any advice would be appreciated.

Years ago I had a 327 engine that would struggle to turn over when hot.  I never did figure what the cause was.  I wouldn't think an  electric fuel pump would be that much impact on current draw (normally 3-4 amps).  I'd first make sure that the issue is actually a current issue -- try a voltage meter at the starter to see what the drop is when cranking, and compare it to voltage right at the battery.  If there is a great difference it could be the wiring e.g. maybe a connection is not good enough.  If the voltage difference is negligent, and the battery is good, it could be a weak starter, or ignition advanced too far.

Hot starts on "The Toy" were an issue until I put a sandwich of gaskets between the carb and the manifold.  The carb was HOT to the touch before I put the gaskets in.  After that it stayed just warm to the touch and hot starts were a thing of the past.

Hot starts on "BLKBRRD" were an issue also because the starter was so close to the header/exhaust pipe.  Installing a "mini-starter" solved that issue as there was more space for air to circulate around the starter reducing the heat soak.

Jim Olson 

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Where I've been in a Corvette...!!!

Doesn't the Start position bypass everything but the starter and ignition? 

You'll need an electric fuel pump if engine is fuel injected. 

1973 L-82 4 spd

So the battery as is, had 12.70 volts. With the key turned to accessories position (blower on and electric fuel pump running) I had 12.23 volts at the starter. While cranking the voltage dropped to 9.64 volts. Is this excessive?  Thanks

Thanks for reply. I have the special spacer between the carb and manifold to restrict heat transfer. I also have a high torque mini starter installed with a heat shield wrapped around it. Both helped but still have the issue from time to time. I also installed a fuel filter with return line so fuel pressure drops to zero as soon as I turn off the car.

Can you measure the voltage at the starter while somebody turns it to the Start position? I think normal voltage drop is around 10.0 to 10.5. If the voltage at the starter is less than that then I would go through and check ground connections and positive connections to the starter from the battery. 

Edit: I found by blocking the exhaust crossover in the intake and wiring the heat riser valve wide open helps cool things down under the hood. It was my daily driver and I never had a cold problem in the winter by doing that.

1973 L-82 4 spd

1: Weak battery. Anything below 10.6 or so volts while cranking is too low. 

2: To much initial ignition timing. If the engine is hard to spin over when hot, and it sounds like it is "kicking back", it has too much timing. You can try to retard the timing a couple of degrees and see if that helps. I have found that when one is kicking back, and hard to crank when hot, that pumping the throttle a couple of times while cranking cools the intake charge, and the engine will fire up quicker. I have also used a "kill switch" to dis-able the ignition/distributer before cranking, to allow the engine to spin normally without having to fight a system that has too much advance on the timing. Once the engine is spinning over, the kill switch is flipped back on, and the engine fires right up.

3: Quality of fuel. With the compression ratio you have, it will require a higher octane fuel to fight the pre-ignition that creates the hard to crank issue to begin with.

Joel Adams
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I have a new battery coming as the current one was only putting out 293 CCA vs the 690 CCA stated. The new one will have 800 CCA.   I have the total timing set at 33 degrees advanced.  I will drop it back to 30-31 if I still have a problem.

Thanks everyone for great input. Gave me many things to look at and test.

Let us know how it works out.

1973 L-82 4 spd