Could some of you that have the thermal coated header from MSA tell me whether or not you use the heat shields. I'm trying to make a decision on this and would appreciate your advice/opinions. Thanks, Cliff.

I use them. I would always use them. If for nothing else, than if gas leaks out of the carbs, it will not drip directly on the header.

I forgot to put the lower one on and the exhaust heat burned a hole in my PCV hose. It's going back on after I finish torquing the manifold down, BTW have you noticed how little torque is called for the exhaust manifold nuts? I just don't trust such a low torque.

I'm going with 10x1.25 studs on the ends so's I can wrench down on them. 15lbs isn't much but I've read to retorque them a few times fairly soon after install. Did you put your new manifold gasket on with the metal core closet to the manifolds? The thicker side of gasket material to the head right? Oh and I thought your cylinder head was new looking at those pictures. Great job!

I have the stock heat shield installed over my header. Of course with the SUs, I don't know how you could not install the heat shield, since that is where the throttle return springs attach.

I have the stock heat shield installed over my header. Of course with the SUs, I don't know how you could not install the heat shield, since that is where the throttle return springs attach.

Not so with F.I.

You know I did not know that about the manifold gasket. The one I got from MSA is a bit different then the felpro I used last time. I just looked at it installed and I cannot see a thick or thin side. 50/50 chance?? I am not sure why my valve trane is so clean the valve faces though had quite a bit of carbon build up.

good luck, looks like you are a step closer than me.

I have the thermal coated 6 into 1 MSA header on my 240Z. The car has early SUs and I was lucky enough to acquire an early heat shield (no cut-out for the exhaust manifold heat riser)--it's pretty small though and the headers snake out below it a good bit. Like other responders have mentioned, don't see how you could not use a heat shield of one kind or another because it provides an area to hook the carb return springs & protects the PCV hose (if used). I've seen the springs hooked on a screw, or something could be welded to the header itself to hold the springs. A larger shield would be preferable if you ask me. I wanna know if anyone has fabricated a larger one that will clear headers and offer more protection from fuel leaks? It's happened to my car once when the fuel bowl overflowed and raw gas was dripping out onto the hot header (YIKES!). And those dinky fuel hoses are certainly very very close to the whole exhaust as it is. If I had some suitable sheet metal tools, I'd try to make a bigger heat shield...only downside is that it would spoil the cool factor of oogling the headers, but form should follow function especially when heat is concerned.

I run a heat shield, a coated header and the 6 to 1 header is wrapped. Boiling 93 octane fuel while struck in traffic isn't my idea of fun.

Cannot get rid of this heat in my 1972 240z with twin su roundtop carbs? Car still misfires after 5 to 10 minutes in stop and go traffic. I thought i had a problem in the engine and the problem is clearly heat. Any advice on how to tackle this?

Fit some efficient heat-shield material and run it from engine head to chassis rail.

https://www.google.com/search?q=nimbus+heat+shield&rlz=1C1VSNC_enFR576FR576&oq=nimbus+heat+shield&aqs=chrome..69i57j69i59j0i22i30l2.4227j0j7&sourceid=chrome&ie=UTF-8

There's a lot of turbulence behind the radiator - does anyone seriously believe the the hot air rises only vertically ?

2 hours ago, jalexquijano said:

Cannot get rid of this heat in my 1972 240z with twin su roundtop carbs? Car still misfires after 5 to 10 minutes in stop and go traffic. I thought i had a problem in the engine and the problem is clearly heat. Any advice on how to tackle this?

 Have you ever tried driving with the hood unlatched to see if the problem reoccurs? It'd be an easy experiment.

@rossiz louvered his inspection covers on the sides of the hood. I don't remember if heat was his reason for doing so but it looked good and I'll bet it lowered the engine bay temps.

I have not drove this way. I did open the hood with the engine idling while parked. Temperature lower a little bit. But its not the same stop and go traffic vs parked at idle. More heat is generated while acceletating and stopping in 10 to 15 mins traffic jams