possilbe plan for my plastic intake

supertrick_05 · Post by **supertrick_05** » Sun Mar 16, 2008 2:35 pm

I have seen people powder coat plastic intake manifolds from the newer Vettes, as well as the flimsy plastic valve cover covers...I have an extra plastic intake manifold that I may try experimenting with...just as soon as I get my powder coating gun, and play around with different scrap metal first.

Not sure if anyone here would know this, but how hot do you think those manifolds can withstand? The Corvette intake manifold was cured for 40 minutes at 375 and the flimsy plastic covers at 350 for 40 minutes.

turbodudey · Post by **turbodudey** » Sun Mar 16, 2008 3:03 pm

Temperature info from wikipedia: http://en.wikipedia.org/wiki/Polycarbonate

Looks like the plastic will start to get soft at just over 300 degrees. Obviously the higher you go the softer it will get. With the actual melting temp over 500 degrees you could probably get away with baking at over 300 degrees. You'll just have to be carefull handling it when it's hot so as not to deform it.

Post by **racer12306** » Sun Mar 16, 2008 5:34 pm

Are you sure it isn't a special kind of powderdcoat? I thought powdercoating stuck to the metal by electrostatics until it was baked.

kevo · Post by **kevo** » Sun Mar 16, 2008 8:05 pm

If i were you i would just stop right where you are. The intake manifold, throttle body and valve cover are made of a composite consisting of nylon, glass and various resins. They have a special coating inside and outside to prevent deterioration. i don't know how much heat they can take but personally i wouldn't bother messing with them at all.

Post by **jonnymopar** » Sun Mar 16, 2008 9:53 pm

Unfortunately, I have to second that one. There's no guaranteeing that once you've got it looking good and ready to put back on the car, you might start bolting it up and find that the mating surface won't sit flush with the head anymore.

If you are really looking to do a custom intake, maybe the 1st gen intake would fit. That would be WAY cheaper than going with a Magnum setup. I know the throttle body faces straight up on the 1st gens, but I'm sure you could either use a 90-degree silicone elbow, or completely eliminate the turn-up from the end of the intake and somehow make it so the throttle body mounts relatively similar to how the 2gn works.

turbodudey · Post by **turbodudey** » Sun Mar 16, 2008 10:44 pm

If you really don't care about messing up the plastic manifold, I don't see why you shouldn't at least try. If the mani isn't actually polycarbonate, but turns out to be some other polymer that melts into a lump of goo, then you may be out a mani. I guess I would be surprised if it wasn't polycarbonate though. Seeing as it wouldn't be horribly abnormal for the manifold to experience temps aproaching 220 degrees while bolted to the head...

supertrick_05 · Post by **supertrick_05** » Sun Mar 16, 2008 11:54 pm

The 1st gen manifolds are still plastic...

Post by **jonnymopar** » Mon Mar 17, 2008 9:17 am

supertrick_05 wrote:The 1st gen manifolds are still plastic...

Really?? I could have sworn that they all got aluminum intakes. I take all that back then. Probably because I'm used to working with the 1gn DOHC stuff, which got aluminum manifolds.

Post by **occasional demons** » Mon Mar 17, 2008 9:37 am

The 1gn intake doesn't clear the starter/heat tubes on the 2gn. I test fitted the one I made my ghetto intake before I hacked it up. They will bolt to the head obviously, but the other stuff doesnt clear, unless the 1gn heater tubes/starter are used. Plus I can't see there being any benefit, even if they were aluminum. The outside can be painted with normal spray paint, altho it scratches easily.

kevo · Post by **kevo** » Mon Mar 17, 2008 11:03 am

supertrick_05 wrote:The 1st gen manifolds are still plastic...

some are aluminum. look around for them. You can always make a custom mani even if you don't plan on making big power. simply make the plenum smaller than the plans that are openly available online.

hul kogan · Post by **hul kogan** » Mon Mar 17, 2008 11:53 am

supertrick_05 wrote:The 1st gen manifolds are still plastic...

nope, they had aluminum SOHC manifolds on some 1st gens. they are pretty rare from what i have gathered.

i actually had two of them up until a couple months ago when the same guy bought both of them from me.