I have actually tried using a giant finned heat sink, and it appeared to make no difference. Then, I got a metal "loaf pan," like you'd make a loaf of bread in, or a meat loaf. I filled it with water and put it into the freezer until it was frozen absolutely solid all the way through. I placed it on top of the hot intake manifold... waited... most of the ice melted... took the pan off, and the manifold was still hot as hell.

None of this is even remotely scientific... but in my opinion, it will take a LOT to cool down the intake manifold to the point where you see significant power gains.

 

Like I said, I did it twice so don't feel bad at all.

 

Do you just need a drawing of the ports and bolt holes? If so, a tracing off somebody's heads or stock manifold would work.

If you need help in the fiberglass forming techniques I have some experienct there. I'd suggest forming the runner & plenum shape from foam, applying melted wax to smooth the surface, then glassing over, and finally using solvent to remove the foam. The marine epoxie I usually use wouldn't like the heat (West Systems). What kind of resin will you use?

 

Actually I decided to use an intake manifold gasket for my template so il'l pick up a cheap one from the zone at some point. Resin they make resins that can handle the temperature I'm a little more concerned about gasoline exposure and fabing the bungs for the MAP sensor and the Injector bungs. I know how to do this with carbureted engines.

 

E-mail me @ d48mclain@tx.rr.com and I'll send you a picture or two of my sheetmetal intake. My heads/intake is matched to off road LT4 gaskets and have 6" runners with a monoblade.

It's a lot of work. Jeb Burnett did the intake and I reported it to the larger ports and also epoxy tapered the runners to merger better into the heads. Must have 40 hours just doing that. Polishing....another 16. Jeb said he had 50 hours into it already.

 

subscribing.

I agree that measuring energy gain of the incoming air is not the way to assess effectiveness of this mod in terms of engine power gain. Interesting thread.

 

For the bungs, you might consider using a filler with the resin to make a putty (peanut butter consistancy). Then either make solid blocks in the manifold using this filler and machine to fit, or 'mold in place' using something as a core.

Using injectors as an example: Take the o-ring off an old injector. Then tape over or fill the groove to give you a smooth plug shape. You could use a dowell or better yet an aluminum rod turned to the right size. Coat with preferred mold release, mount in place in empty 'pocket' on manifold, then pack with your putty. After it cures, pull the plug out and clean up the hole edge and fill any bubbles. If using aluminum rod you can omit the mold release, and just heat the rod up enough that it will slide back out. Aluminum powder makes a great filler, especially where you need to tap threads. I also use Graphite powder, glass microspheres (lower thermal conductivity and lightweight) and various fiber fillers. Talc can work too but sometimes kicks the resin off too fast. Test a batch with filler first to make sure you like the results.

The ramair intake on my gokart was made with foam core layup, and aluminum filler for the threaded holes.

Using a gasket will probably leave your runners too big for the heads, requiring more filling later to port match.

Please make a construction thread when you do this, it will be really fun to watch/help.

 

I agree too. But calculating the energy gain of the air "is" a "way" to show the effectiveness of a thermal coating in general for those that cannot see the "concept". It's a mental help. I understand heat transfer somewhat and the concept is plain to me.

If I have the choice between 140F air or 130F air then I'm taking the lower temp.


Karl

 

No doubt. I'll take the cooler intake charge as well. One of the 1st mods anybody does is a CAI. But it is misleading to take the dT of the incoming air to measure power gain. I nice mental exercise, just relatively useless in predicting power gain.

 

Read this thread from the Edelbrock web site. Look about half way down for the comments regarding coating the manifold. Interesting.

http://www.edelbrock.com/automotive/...r99/index.html

 

They are discussing carb'd intakes. If the injectors are low and close to the ports then smooth runners doesn't matter. However if I do attempt the fiberglass manifold I will try to locate the injectors as far up the runners as possible for improved atomization, so roughing up the runners will become an issue.