Down Pipe question

[86Tona]

I read somewhere that if the down pipe is wrapped to keep in the heat it does two things. It allows for better exhaust evacuation by putting hotter gasses in the first part of the exhaust system and it keeps the engine compartment cooler. The later part makes sense to me and if this does result then it also makes sense that a cooler engine compartment would help to make for more effiecnt power making. This result could be an increase or in power or a lower loss due to temps being cooler.
While I'm typing this I am also wondering what would happen to that heat if the down pipe is wrapped. My guess is that it would be disapated by the cat and back pipes. That said and if it's a way to improve things (if only a little) then some heat shields under the car would be a good idea to help keep the interior cooler.
Comments?

[gkcooper]

How about wrapping it all the way to the muffler? I am planning that.

[nemesismachine]

Why not get the downpipe jet hot coated?

[86Tona]

All good suggestions but what about the original question. Why do it at all unless there is some benefit?

[Polygon]

Quote:

Originally Posted by nemesismachine Why not get the downpipe jet hot coated?

You're looking at between $75 and $100 to do that. I asked this question about a week ago and everybody pretty much said it wasn't worth that. There is a member on here that will do it for $70, shipping included.

As for the original question. Heat wrapping can also store moisture causing corrosion. You're better off getting a high temp coating if you feel it is worth it. Either wrapping or a high temp coating will store the heat energy in the pipe keeping out of the cabin and will help with exhaust scavenging. Also, the heat energy will be dissipated after that by the cat and the rest of the pipe, but that should only concern you to reduce cabin temperature. If that bothers you then an undercoating, heat shield, or high temp coat the entire exhaust.

[BLASINTEBO]

There are some vague benefits, like thermal efficiency... and keeping the heat where it needs to be... and it's not a hard mod to do, if you are putting a bigger downpipe in...

[86Tona]

$70? For the coating perhaps but to wrap it there are products like this one from Eastwood.

http://www.eastwoodco.com/shopping/p...keyword=DEI001

If the benefits would be that it keeps the heat away from the intake as well as other benefits associated with running the engine just a bit cooler this would be a good thing.

[Polygon]

Yes, the wrap is a lot less expensive but I was just saying that it can trap moisture.

[86Tona]

If the down pipe is stainless that would help. Would the ceramic coating have the same thermal factors as does the wrap?

[detobias]

summit racing has the 1" wrap on sale 1"x50' easy to wrap; thats what I used on my DP

(and I just used some good quality thin wire to hold it)

http://store.summitracing.com/partde...5&autoview=sku

[Polygon]

Quote:

Originally Posted by 86Tona If the down pipe is stainless that would help. Would the ceramic coating have the same thermal factors as does the wrap?

The coating would be better if you don't mind spending the money. Jet Hot has a 1,300 degree coating and a 2,000 degree coating, plus the coating would prevent rust. If you have stainless pipes that isn't as much of a problem.

[86Tona]

I googled a DIY ceramic coating product. It seems there is some you can buy that will allow you to do the coating yourself. Since it is somewhat expensive it would be better if a few folks decided to do this and everyone chipped in to have theirs done with the product that must be purchased. This would lower the per piece price a great deal.

[86Tona]

***UPDATE***

http://www.techlinecoatings.com/Exhaust.htm

It seems that the process of ceramic coating is not rocket science. There is a product that the above link that sells for $19.95. It is 4 ounces which they say is good for a pair of small headers. So my guess is that one $20 supply would do two down pipes of about 3' in length. Some of these materials do need to be oven baked so this may prevent some folks from doing it. However my brother has a shop that repairs aircraft propellers. They also have an NDT shop and a plating shop. When plating they bake these large pieces over time. So for me to do my down pipe will cost $19.95 with enough to do the manifold too. Very cool.