Thinking about heat shielding options.

[blkcorvair]

Im looking for some heat shielding options. It seems that my car will heat up and run about 205deg if not in open air with speed, Than its causing some fluctuating in my fuel misture and I noticed a bit of fuel in the overflow as well as a quick real rich condition. Looking to stop some of the heat transfer to the carb. Right now there is no heat shield what so ever. Thought about obtaining some thin aluminum and making a clamp on shield right to the header. or coating the header, or wrapping the header (Dont like option number three) or maybe a heat shield mounted to the carb..... hmmm..

 

[jlaird]

I would think a home made heat sheld would work just fine. Heck they just a peice of thin metal to deflect the exhaust/engine heat from the carbs.

 

[Morris]

Header wraps ARE ugly. But my car will run at whatever temp thermo I put in her. I put a 145° thermo in there... my car runs at 145°. With the car hot, I can touch the wrap without burning my finger.

Ugly... but effective.

 

[blkcorvair]

morris what wrap did you use? I bought one off ebay and 1st it turned rock hard than my header actually burned up inside. (Granted the original header was pretty old), but I have no problems with the way they look. Like things to be like you said effective!

 

[racingenglishcars]

Yeah, exhaust header temperatures can be high, especially if you're running high fuel/air ratios. Wrapping in that case can melt the pipe. Maybe some ducting is the way to go.

 

[aeronca65t]

A simple heat shield between the carb and manifold will help. You can use around 0.032" aluminum sheet and extend it out as far as you can. You can use the carb gasket to figure out the hole size.

If you want to get trick, you can use a double-plate heat shield with spacers (small washers) sandwiched btween the plates to keep an air space...this can be very effective in terms of insulating.

I have DEI header wrap (from my local speed shop) held on with stainless steel safety wire. It's ugly but has been on the car for about 5 years. No issues with it at all. Seems to help.

Be sure you have a good radiator. The 1500 rad is a particulalrly good unit if it's clean. My old one was partly clogged and it still did a decent job. But I ended up getting it re-cored after I accidentally stuck a giant screwdiver through it (duh!) and now it's even better.

I took an old thermostat and took the guts out of it so it just acts as a restrictor (or a "blanking plate" as racer's call these). It's a bit too cold in the Fall, but keeps the car at a nice 165F all day long in the Summer. This is a bit cooler than ideal (for power), but it also promotes lower oil temps, better oil pressure and probably longer engine life (a good trade off if you're an amateur like me). To me 205F is too high for a 1500. They're too fragile for sustained high temps.

Be sure not to run too much anti-freeze (it doesn't reject heat as well as water). About 20% AF and 80% H20 is good.

Running slightly richer air/fuel ratio will also reduce temps. This may be less than ideal for power, but again, reduces piston and valve temps for longer engine life and even keeps the header cooler.

 

[zblu]

Put one on my AH BN1, sandwiched between 2 bakelite intake spacers so as not to transfer heat from the ali deflector to the carb bodies, can put pic up if wanted

 

[Morris]

I have used two brands of wraps. One was the B&H house brand and the other was what they had on the shelf at Advanced Auto.

They do get brittle fast and do not hold up well to manhandling once they have been used for a while (which is why I had to replace).

 

[jcatnite]

I've seen an engineered blanket that curls over the headers but won't completely encase them as a wrap would. I want to try one but they are around 80 bucks a pop. I think I saw them in the moss catalog. I have vapor lock issues and would like to sheild the intake manifold from the headers as well. The problem was much worse with the ZS carb on the stock manifold. Once I switched to the DGEV on a cannon manifold it isn't as bad but still present.
JC

 

[blkcorvair]

I've seen an engineered blanket that curls over the headers but won't completely encase them as a wrap would. I want to try one but they are around 80 bucks a pop. I think I saw them in the moss catalog. I have vapor lock issues and would like to sheild the intake manifold from the headers as well. The problem was much worse with the ZS carb on the stock manifold. Once I switched to the DGEV on a cannon manifold it isn't as bad but still present.
JC

looked at this too. Jet Hot will do my whole exhaust system under $300. Very tempting. But not wallet freindly at the moment.

BTW that blanket is available at Jegs / Summit much cheaper