A little weight loss

[joe payne]

Just getting my car ready for the smog test and thought it might be a good time to find out the weight difference between a cat converter on my 78 sc and a cat bypass. The stock cat weighs 14 lbs. and the cat bypass weighs 6 lbs.
An 8 lb. weight savings in addition to a little more exhale in the upper rpm's.

[911 in SC]

Cool! What kind of wrap is that? Where did you get it?

Thanks,
Mike

[joe payne]

Originally Posted by 911 in SC

Cool! What kind of wrap is that? Where did you get it?

Thanks,
Mike

Hi Mike,

It's Thermo Tec header wrap. From a local hot rod shop. It really helps keep the temps down under the heads. It looks pretty trick too.

[JBO]

Not sure how much truth there is to it, but I read somewhere that one problem with the wrap is that it can trap moisture and cause the metal to rust out quicker. Anyone else heard this? I thought about using it myself.

[gtc]

Even from a cold start up, how could any moisture last more than a minute or two on any part of the exhaust? It seems to me that it would vaporize and pass through the wrap quite quickly.
I've never used the stuff though.
If I were running headers or a similar cat bypass I'd get them ceramic coated in silver inside and out, in hopes that they would radiate less heat. I don't know if that works as well in practice as it does in theory.
Edit: Ah man... too slow with the typing skillz...

[911 in SC]

Originally Posted by joe payne

Hi Mike,

It's Thermo Tec header wrap. From a local hot rod shop. It really helps keep the temps down under the heads. It looks pretty trick too.

I can certainly understand how it would help keep the heat down, considering how close it comes to the lower valve cover! I know what a PITA it can be adjusting valves...

I have read and heard about the moisture issue too, but especially with the 911 exhaust, I think any moisture at all will vaporize in a matter of moments.

Thanks for the info. I'll have to check around to see if any of my local hot rod shops has it. (I do miss not having Super Shops around sometimes...)

Thanks,
Mike

[joe payne]

Originally Posted by 911 in SC

I can certainly understand how it would help keep the heat down, considering how close it comes to the lower valve cover! I know what a PITA it can be adjusting valves...

I have read and heard about the moisture issue too, but especially with the 911 exhaust, I think any moisture at all will vaporize in a matter of moments.

Thanks for the info. I'll have to check around to see if any of my local hot rod shops has it. (I do miss not having Super Shops around sometimes...)

Thanks,
Mike

Yea, you're right. More clearance getting to the lower head valves.
Not real sure about moisture either. It's rather dry here so not an issue.
If you look closely at the picture you will notice that I wrapped the cross over pipe too. It was a while you're in there deal when we did the head studs.
Oh, and just order the header wrap on line.

later.