See: http://www.teamswift.net/viewtopic.php?p=134543&highlight=civ+embeded#134543 This guy created intake manifold gaskets using phenolin and significantly lowered the intake temp on his Swift (yeah, I know). Would similar usage provide any benefit to the naturally-aspirated 3x8 series? Edit: ok, he actually used nylon, someone else suggested phenolin. The purpose of the gasket is to insulate the intake manifold from the heat in the block
We have made similar for "certain" companies and have always been made from Peek. Nylon only has a long-time serving temperature of approx 200 deg F - Peek has over double that with still the same thermal conductivity & also has a greater tensile strength of nylon. Now days there are a multitude of themoplastics out there with some pretty impresive figures to go with them. We are actually working on a project at the moment where we are considering making some of these for the 348 as a customer of mine is doing certain major modifications to his inlet side of his engine! Paul
Sign me up. I'd like to buy them from you for the 348. Will there be a "no drilling" option (it's OK if not, too)? Throttle body spacers, too?
ND, Fortunately on the 348 manifold they only use 2 of the holes for location - the others are oversize (9mm dia IIRC) but we will have to look a little further before we make a final decision on design etc as this part is still being talked about - if anyone needs manifold plates for throttle bodies we are just about to get them on the go! As for offering any type of kit - this is still way too early in the game to even think about it!! At the moment its purely a one off!! Paul
As well as your average family sedan They cam stock on the fuel injected VW Type 3 (Squareback, Fastback, Notchback, and the Type 34). Used on the intake runners to isolate them from the heads. I believe there's a phenolic spacer used under the mechanical fuel pump of the same engines (carb versions, of course).
I'm pretty sure there are a couple of phenolic spacers between the 2 SU carbs and the manifold on my 1973 240z!
348 paul, this is very common on carburated cars to prevent too much heat from vaporizing the fuel and causing vapor lock. I believe the gaskets that are being discussed are being used between the intake manifold runners and the block to prevent engine heat from abnormally heating the runners. My 246 has the phenolic spacers under the carbs as well.
As a followup, the example in the link was a turbo'd car, so obviously intake charge heating is an issue. Is it as much of an issue in a naturally aspirated motor? I'll need to make custom intake gaskets anyway, so I cannot see a downside of using this material. Am I missing something?
Sorry Gary - It was just a passing comment I do remember this from early days of swapping various carbs over on Ford pinto blocks and not using any thermoplastic spacers. You learn by your mistakes!! Paul
I hate to be a wet blanket, but I've looked at this issue before, and thought you might be interested. While insulating spacers are useful, and even necessary,on carbureted engines, their purpose, as folks have stated above, is to stop the fuel in the bowl from getting hot. When you start talkig about doing this to a fuel-injected car, what people seem to be after is cooler intake air. If so, I don't think inslating the manifold is going to be all that useful. Reason being that the air just doesn't stay in the manifold long enough for it to get any significant heat transfer. A 3.2L engine at 6000 rpm is pulling in almost 10,000 liters/min of air. Now I'm not familiar with the intake layout on these cars, but even if the volume of the manifold is several gallons, that still works out to less than a tenth of a second the intake air stays in the manifold. A few degrees of manifold tem difference isnot going to change the intake air temp by even half a degree in that length of time. Just something to think about....
I double-checked my Parts List for VW...you're correct, a standard intake gasket for the intake runner to head. I mis-thought...there is a phenolic spacer but it's for the injector to sit on and it fits inside the end of the intake runner Back to our regularly scheduled Ferrari chat...
Yep. The phenolic spacer will certainly insulate the manifold at the mechanical connection to the hot engine block, but the hot environment near the engine will still heatsoak the manifold even with a spacer. No sense in using one unless it's under a carb.
I agree with the heat soak from a hot engine environment, but as Dubai Vol stated the air just isn't there for a long enough period to be to concerned about, however when it comes to smoother running especially on carburated engines the warmer runners probably contribute to volitization a bit. Now when it comes to extracting every last percentage point of performance then it may become an issue. I have never, however seen racecar engines where they insulate the intake runners. Mostly what you see is efforts made to provide cold intake air and call it good.
Have you considered NASA's aerogel for use as a phenolic spacer or gasket? http://www.mkt-intl.com/aerogels/aerogel_order.html I'm going to be needing this part (some sort of improved spacer/gasket) in the next 3 weeks. Image Unavailable, Please Login Image Unavailable, Please Login
I have been thinking of doing this on Emachine.com There is a small benefit with reduced heat but the real benefit may be something else in helmhotz resonance or what ever. You see if we could get flow and volume similar to the larger 348comp cars I could see a real benefit. In fact with the challenge tube exhaust you might have something here. Slao you could now drill the spacers and insert nitrous oxide and fuel lines in and really have some fun without having to risk the effects of wet mixture in a dry manifold. Now are you guys interested in phenolic spacers? I think it could be a cheap way for extra HP. I got the tube exhaust and dyno access and I'm so lazy if someone will make the spacers I'll be the testor.