I attempted to reseal my Keel manifold today. I had cleaned off the upper portion and the thin plate well, laid down a bead of The Right Stuff, and mated the surfaces.

I used clamps, which was probably a mistake. After giving enough time to cure, I undid the clamps. Turns out the thin plate isn't completely straight, because it bowed up and apart by 1 or 2 mm in a few places. Ugh.

Is the answer to just use a lot more Right Stuff and not clamp the surfaces together? I'm worried about what happens when the manifold is installed and torqued down if I've left much of a gap while it was put together but uninstalled.

Also, I thought Bill Ball and others had indicated that they used 1" spacers inside their manifold. I discovered that my manifold is more than 1" thick, so 1" spacers would just sort of float around in there. In retrospect, I should've measured before purchasing them.

Would love to hear tips from those who have BTDT. Thanks.

 

Although I haven't messed with mine yet, I was under the impression that Bill et. al. used one inch spacers and the stock intake gasket; no right-stuff required.

Dan
'91 928GT S/C 475hp/460lb.ft

 

I used Right Stuff to mate the top and bottom plates to the side wall of the manifold.

But, yes, Brian, the plates will separate once you unclamp them as the plates are not flat to begun with. So, I put another bead on an install it right away. Ralph and the other guys in Colorado had their manifolds modified by Embree. Among the mods: change out the bottom plate for a thicker piece that would stay flat and add more screws to the edge to keep it together. I didn't do that.

I had no idea Andy changed the sidewall dimensions. Even at 1", the blower sits about as high as it can. Sorry about that. I can't imagine it is not a standard dimension.

 

Well, my manifold is like Tony's, in that it's got the 1/4" plate that the supercharger attaches to. So it's possible to take the supercharger off the manifold. Then you have the top part of the manifold (which is cast like an upside down shoebox with the sides part of the structure), which the intercooler mounts to on the inside, then the thin plate, which the intercooler slides into. There's some additional piping that gets threaded in once the pieces are assembled. It's a little convoluted.

I guess I'll take another stab at it tomorrow, once everything is hard enough to scrape off. But I'm concerned because there's a bunch of intercooler crap that has to be screwed together once the top part of the manifold has been dropped into position, so it's not like I can just mate the two surfaces and drop them into the car and reassemble things.

I measured--it's 1 3/16" thick. Go figure.

 

Brian, I have no direct experience with the manifold in question, but why not use something that doesn't really cure/dry, like Yamabond?

 

OK, Brian, yours is one of Andy's cast manifolds, so its going to require different treatment.

The main thing is to try to prevent warping of the thin bottom plate so that you can avoid air leaks there. The outer edges of the plate to manifold seam along the intake runners should be OK if you use the stock gasket with 1/8th inch spacers, like bunch of us have done, along with internal spacers (1-3/16ths in your case) on the main manifold bolts or studs and any other through-bolts, which helps keep the base flat. If you use studs, it can be a bit of a challenge to get these internal spacers to stay in-place as you drop the manifold on. I used bolts and dropped them in before I put the manifold onto the motor. But then you face keeping the gasket located properly. So, what I did was use a couple of studs at the ends for location initially and then replaced them with bolts once the manifold was down. I think I slipped the spacers in for these bolts through the injector holes after the manifold was down and I had removed the temporary studs. Anyway, once you get the correct length spacers, I'm sure you'll figure out a better way to get this installed.

The sealing in the area in the valley is dependent on the peripheral screws and any through-bolts. Embree added more screws to the Colorado guys' units. I added a couple of through-bolts with spacers, sealed with goop. Also there were some studs mounted in the top of the manifold that I changed to either through-bolts with spacers inside the manifold or long bolts with the head inside the manifold, adjusted so the length of the bolt inside the manifold acted as spacers, locking them with a nut against the bottom side of the lid.

 

Anyone have pictures they could share for us that don't have Andy's system?

 

I gooped it all up again and didn't clamp it this time, so we'll see if it works. Before I took it apart, it worked for nearly 4 years, so there's got to be a way to reseal it such that it stays sealed when it's off the car, and also remains airtight once it's installed.

If it needs to come apart yet again, I'll take pictures so those following along in their mind's eye can get a better sense of what I'm talking about.