I pulled the manifolds last weekend because I had a bad boost leak. (I could hear it!) As you may remember I have a slight intercooler leak which doesn't seem to be getting worse. As you also may remember, I'm spraying water/methanol. The runners and valves look pretty clean to me and the goo wasn't heavy. I replaced the stock type gaskets for the cork gaskets but this time I only torqued to 15 nm and the outside bolts a tad less. I realized I was destroying the little O gaskets even with even torque and the manifolds were tilting a little causing my prior problems with them. The car feels a lot better without the leak. Anyone else torquing the outside bolts less than the inside 4?

Les

 

I have new gaskets for these aswell. Easy to remove and install? How can you see a leak in the manifolds?

 

You can usually see where they were leaking after you get them off, if they were. The wetness from the gasoline shouldn't extend past the ridge in the stock metal manifold gaskets. I can get the manifolds off, clean them, and put them back on in under an hour. I have way too much experience.

Les

 

should be 5 5 10 les. never had any issues with this pattern for the inside middle working outward and pushed 22 psi art wot. i ditched the cork and just used the oem gaskets. grip sprayed his with copper and his leaks went away

 

+1

Copper spray on the stockers is the....

 

I still have a set of cork gaskets in the closet. If I continue to have problems I'll try the copper spray. Incidentally, my highest dyno was with the cork gaskets. Hummm. Coincidence? Heck if I know.

Les

 

I just think the cork goes bad over time... I still have cork on, but going back to oem w/the copper spray...Steve is right on the torque procedure as well... it's an aluminum thing... Starting my tear down tomorrow night working thru Friday until done...

 

The cork O ring outer gaskets are falling apart on mine as well but no leak as best I can tell yet. What is 5 5 10 sequence? I used inside/middle out patternas well.

 

I'm guessing we are talking the manifolds to "riser" gaskets not the riser to block gaskets.

Painful question for some - can someone post a link to the copper spray please....no time to search and am planning to do them 2morrow.

and yes - 5 5 10 - if you can explain pls.

 

 

Never heard of it.....

 

5 ft /lbs torque then retorque at 5 ft/ lbs again then final torque at 10 ft/lbs. all from the inside middle working outboard. 5-5-10!

 

Those torque specs work for the stock metal gaskets. With the cork I recommend more steps and stopping at 15 newton meters. I also believe, right or wrong, that the inner bolts have much more gasket surface area than the outer bolts. Therefore using the same torque on the outer 2 crushes (destroys) the cork O rings which is the cause of the cork gasket leaks. I learned this lesson from my previous set of corks that only stayed on a month. As I mentioned before, my highest dyno was with freshly installed cork gaskets. Freshly installed metal gaskets were down a fair amout with no other changes. Same dyno, same tune, less than a month apart, same season, same Island. Just my reality in the land of Don Q.

Les

 

les i believe 15 newton meters converts to 11 ft/lbs. so 1 ft/lb diff. i tried the corks many times and after they heat cycle they are useless if you pull the manis. after using them again and again i just went back to stock and had no issues.

 

10-4 on the 5-5-10 'lbs. gracias

 

cant believe I found a can of that copper spray stright away 2day!
also picked up a sheet of rubberised cork for $16...might try a couple of gaskets

 

Well, there's a new one; I haven't heard of anyone on here cutting their own manifold gaskets? Robs are very affordable if that's the way you want to go. I'm on the side that believes the corks suck, and are only good short term(1 day at the races). And yes, I used the 5-5-10 sequence. Both times that I've tried the corks, I've had the same results. When removed, the very thin smooshed out cork into the port was cooked and getting ready to let go. It would be sucked right in to the valve if that occurred. No worry about that happening w/ the OEM metal gasket. And also to mention; the smooshed out cork is interrupting the air flow a bit. My $.02

 

Anyone who remembers the trouble with the cork and cork/rubber valve cover gaskets of the old days will remember the troubles with them. They always ended up getting hard as a rock after constant tightening to stop the oil leaks. The areas under the screw heads of the covers became distorted and had to be flattened out before fitting new gaskets, the covers were sheet metal and bent easily. I am sure the new cork/rubber gaskets formulations are better than they were but .....

I have new gaskets on order and I would not fit cork gaskets in their place. I see that as increasing the risk of bending the metal covers and then having trouble with the use of the stock gaskets. The few screws used in this application makes holding down bent plenums even harder.

Just my opinion, which isn't worth too much at times.

 

I have several sets of barely used metal gaskets. If I used the copper spray would they be reusable? Just asking. Since Rob sent me the manifold bolts with lock washers I haven't had a problem with the bolts coming loose. They stay put without loctite. (Most won't ship the copper spray to P.R. so I'll order some from the local autoparts store)

Les

 

No. They aren't reusable. The crushing of the metal is what makes the seal and the copper spray just helps with the seal. I re-installed the Rob mani's on my coup last night using the metal gaskets. My cork gaskets were actually sealed really well, and were not showing any signs of leaking.