Crate 350 - no holes to mount plug shields

[brown7373]

My 350 crate engine does not have holes on one side of the block to mount the spark plug shields. I assume that drilling and taping an engine on a stand is nearly impossible. Anyone solve this?

[Mike C]

Cast iron drills and taps easy. Are the bosses present in the casting? My concern would be drilling into water jacket. But if bosses present and use a drill stop and bottoming tap should be straightforward.

[Keystone_Hate]

Don't run the heat shields. Why would you spend the time and money, possibly risking completely screwing your block, to run a $20 part that really doesn't do anything?

[CaptRMW]

Originally Posted by brown7373

My 350 crate engine does not have holes on one side of the block to mount the spark plug shields. I assume that drilling and taping an engine on a stand is nearly impossible. Anyone solve this?

You are likely missing the hole at the rear of the passenger side. Julio thinks the starter brace hole is it and thinks it is done. I just drilled and tapped the second one in a year last week and it is not that much of a job. They have no doubt built thousands without this hole. Measure the depth of one of the holes and measure the location precisely. Check the drill size by fitting a drill bit into one of the holes. You will need a bottom tap. Good luck. Roger

P.S. If you are missing more than one hole I would call the engine supplier and invite him to send someone over to do the job.

[B. W.]

Mine doesn't have holes either. I didn't run heat shields.

[CaptRMW]

If you are running headers the heat shields will not do anything but if you are running rams horn manifolds your spark plug boots will be fried by the heat, or you can get insulating boots to protect them. GM was not known for putting things on these trucks that didn't serve a purpose.

[Mike C]

Originally Posted by CaptRMW

If you are running headers the heat shields will not do anything but if you are running rams horn manifolds your spark plug boots will be fried by the heat, or you can get insulating boots to protect them. GM was not known for putting things on these trucks that didn't serve a purpose.

I totally agree with GM not putting things on for no reason. But I have run 2 1/2" 'vette manifolds on my Jimmy for nearly 20 years and the wires have been fine. I routed them down and along the oil pan then back up the back of the block to the distributor. (Buy some 75 Corvette wires if you are running HEI).

I would guess my spiral wrapped Taylor wires and boots are significantly more heat resistant than the vintage GM wires however.

[brown7373]

I bought a 3 piece tap set on Amazon and a #7 drill bit, used a center punch to mark the spot and drilled and tapped the hole. It was easy to do and took only a few minutes.