70 Ignition Shielding?

[Mike F.]

This is for a 70 Coupe L46.

Can someone explain why there are two types of heat shields for cylinders #1 & #3? One page of the AIM shows a triangle shaped heat shield (item #18) and another page shows a straight type heat shield (which is common for the other cylinders).

If you install the triangle heat shield the outer chrome heat shield cover will not go over it. Any ideas?

TIA,
Mike

[Terry M.]

Re: 70 Ignition Shielding?

The triangle heat shield is made to go over the temperature sender for the IP gauge. On the Driver's side head it is between the #1 & #3 cylinders. and on the passenger side the same drilled and tapped hole in the head is for the TCS temperature sensor between the #6 and #8 cylinders. And yes the chrome shield will go over it on either side, with a lot of cuss words and bent sheet metal. Best bet is to leave the exhaust manifold bolts that attach the ignition shield brackets loose and get the wing bolts started through the holes in the ignition shield, then tighten the wing bolts, and last tighten (properly torque) the exhaust manifold fasteners. That order of assembly will bend the brackets into shape. And now you know why so many early C3s lost their ignition shielding early in their life.

The part that is shown without opening for the temperature sender is where the draftsman failed to change the drawing from the 1968 drawing where the temperature sender (for the IP gauge) is in the intake manifold.

[Mike F.]

Re: 70 Ignition Shielding?

Terry,

Thanks for the info..

Your answer now has me asking another question. Do I understand correctly that the triangle type heat shield should be for both locations, cyl. 1&3, and cyl. 6&8?
In my first picutre, item #19 is the heat shield for cylinders 6 & 8, it's the straight type.
AIM wrong?

[Paul O.]

Re: 70 Ignition Shielding?

Mike

If you have a temperature sensor which you should between 1&3 and 6&8 you need the triangle heat shield with sensor opening. The other shield will interfere with the sensor and wiring.

Paul 18046

[Terry M.]

[Kenneth B.]

Re: 70 Ignition Shielding?

Mike,

Paul has it right. If you have both the temperature sensor for the gauge (left front) and the temperature sensor for the TCS system (right rear) you will need two sets of the two pieces shown in your second from the end photo. You will have to deform the heat shield (the inner piece) somewhat in order to get the ignition shield (the outer piece) on the engine.

Full disclosure: The heat shield (inner piece) on the right rear was missing from my car on delivery. It was never installed at St Louis. I added it, and the missing spark plug wire rubber grommet at the driver’s side distributor shield support that they also left off.

TELL ME IT ANT SO JOE. A lot of people now think that all the Corvettes left the factory perfect.LOL I have stories about SN #62 78 pace car I had with 3 mi. with broken T-top glass,bad paint & way more things wrong that GM let ship to a ST. Louis dealer that way.

[Terry M.]

Re: 70 Ignition Shielding?

The paint job on my 1970 was and is a POS. A large hocker rubbed through the metallic on the rear deck. I still haven't figured out the extra five bolts I found under the carpet on the 1970. I have to say the C6 is a whole other story. I think I got the entire car I paid for, and the paint job is superb. However the C6 is so complicated I could have failed to find some missing pieces and I would never know it. I susopect we were just expecting too much of the old cars, and we restore them too well -- but that drags this thread where it shouldn't go. We were talking about spark plug shielding. Let's stick with that and save the rest for over beers.

[Mike F.]

Re: 70 Ignition Shielding?

Mike

If you have a temperature sensor which you should between 1&3 and 6&8 you need the triangle heat shield with sensor opening. The other shield will interfere with the sensor and wiring.

Paul 18046

Actually, the straight type heat shields will fit under the temperature probe without and issues. (Mine is currently set up that way.)