Thread: intercooler gasket information needed

for those of you with intercoolers, im about to install an ssic so ill be needing some form of gasket. i would assume that i could use two supercharger gaskets with the centers cut out for the intercooler, which i would like to do. i have heard a lot of people say that they use rtv, but i would rather not if its not needed.

so let's hear how you all put yours together.

come on, seriously? this would take seconds to answer for someone that has done it before.

sc gasket on bottom and one on top of ic

awesome. good deal.

Only use a thin film of RTV if you decide to use any at all. When using GM gaskets, you would want to use a very small amount of RTV where you trim off any of the red seal. And yes a gasket on both side of the IC. Watch tha you don't block the PCV passages.

I have done 4 IC installs, and ended up using a generous amount of RTV for all of them. The few that I did not use much RTV on, I ended up having to take back apart for vac leaks anyway.

These were all using the green ZZP gaskets. I have no experience with GM gaskets, but if you are using the green gaskets from ZZP, do yourself a favor and do NOT skimp on the RTV. You will be super pissed when you realize it all has to come back apart due to a vac leak. Pay special attention to the area directly underneath the snout. There is not a whole lot of room to play with there.

^^^ the garlocks are crap. It's better to trim the GM than use those green ones.

Zach, may be right about the using a little more RTV on the IC. I forgot some of them don't sit flat like the s/c to LIM matching surfaces do.

So the million dollar question is...


"Are you using the gar****s or the GM gaskets?"

I continue to use the garlocks, because I have been able to re-use them. If I could do it all over again, I'd plunk the money down for the GM gaskets.

YMMV though, as a local guy used garlocks on his ZZP S2 setup, and used NO RTV at all, and claims no vac leaks. Not sure how he pulled that off, because nearly nobody else can. But yeah. Just felt like saying that.

i hate those garlock gaskets. i tossed the one that i had before because it was crap. the paper GM gaskets have worked awesome for me in the past, so i was planning on sticking with those.

id love to stick with no rtv, because i feel that it would be best that way.

and just to answer all of my questions all at once..i need the longer bolts for an ssic, can anyone tell me how long and what thread size those should be, 6mm? i want to get some nice bolts instead of the crappy ones i have now. if they really only need to be an inch longer than the stockers (ssic = 1" ic core) then ill just measure them up myself and go to the hardware store.

Originally Posted by Reptile

If you want the best gasket hands down...use a GenV gasket. Some trimming required in the outlet area, but you get the benefit of having the metal impregnated gaskets. It will also help with the big drops in pulley sizes and the extra boost you will eventually develop.

Please explain why the metal impregnated will help, as I have an IC to install and am interested. I already have the precut 2 garlocks that came with the Stage 2 and two GM Gen 3 gaskets to trim.

Lee are you going ICd again or is this on another car??? For the SS IC and the Gen Vs Garlocks come with the kit and work ok if sealed properly. I was never a fan of the gasket but when you are stuck with using them then they really arent that bad. I too would prefer using the OE Gen V gasket but nobody locally stocks them and they are a bit pricey so most people either cant afford to wait a day or two and dont want to pay the extra $$ for them. I talked to Zooomer about the garlocs a long while back and he told me to use the gray GM sealant and put a little bit on both sides of the gasket where it needs to seal so thats what I have been doing with them. I will put a very small bead and then smear it with my finger. I have done this on numorous installs and never had a vacuum leak. Brian I dont think the Gen V gasket will work at all with Gen 3 housings because the outlet hole is too larger and wont seal because the base of the outlet is moved quite a bit farther towards the nose on the Gen Vs. For the plain ol Gen 3 housings and intercoolers then using the OE gasket on the top is fine and depending on what IC and intake manifold you are using will work on the bottom also.

Originally Posted by Trannyman95

Lee are you going ICd again or is this on another car??? For the SS IC and the Gen Vs Garlocks come with the kit and work ok if sealed properly. I was never a fan of the gasket but when you are stuck with using them then they really arent that bad. I too would prefer using the OE Gen V gasket but nobody locally stocks them and they are a bit pricey so most people either cant afford to wait a day or two and dont want to pay the extra $$ for them. I talked to Zooomer about the garlocs a long while back and he told me to use the gray GM sealant and put a little bit on both sides of the gasket where it needs to seal so thats what I have been doing with them. I will put a very small bead and then smear it with my finger. I have done this on numorous installs and never had a vacuum leak. Brian I dont think the Gen V gasket will work at all with Gen 3 housings because the outlet hole is too larger and wont seal because the base of the outlet is moved quite a bit farther towards the nose on the Gen Vs. For the plain ol Gen 3 housings and intercoolers then using the OE gasket on the top is fine and depending on what IC and intake manifold you are using will work on the bottom also.

Dave yep I'm IC'ing the SS again. There is a Stage 2 with ZZP Frozen boost style FMHE sitting on my shelf. I just have to will myself into taking the bus to work for a few days so I can do the install in my typical OCD style. Good info on the garlocks and the GM sealant. Since I have both the Garlock and OE Gen 3, I may do as you suggested and use the garlock with GM sealant on the bottom and OE on the top.

I've not heard of anyone having problems running the Gen 3 OE gaskets. That's what I wound up using on my Stage 3 IC w/o any problems. They still looked good when I pulled the IC off.

so im gonna plan on using 2 oem gen3 gaskets. bolt sizes anyone?

Originally Posted by Bio248

so im gonna plan on using 2 oem gen3 gaskets. bolt sizes anyone?

Without reading back through everything, it may be easier to just buy the stainless steel bolts from ZZP ZZ Performance SSIC Bolts
along with your GM gaskets.

Other than that, you will likely have to just pull your bolts and add an inch to what ever they are, like you mentioned earlier. There is more than one size bolt, a couple are longer than the others.iirc

I could measure the length of my Stage 2 bolts for you and you could subtract the difference (1.25in iirc), but I have no way to tell you what the thread size is.

im just trying to think if i can get them cheaper from the hardware store than having to get the prices marked up through zzp, same with the gaskets. shipping is also an issue when i can get things around town.

Originally Posted by Bio248

im just trying to think if i can get them cheaper from the hardware store than having to get the prices marked up through zzp, same with the gaskets. shipping is also an issue when i can get things around town.

Understood. I'll go ahead and give you the length and quanties of my Stge 2 bolts, later this evening. Surely someone knows what the thread is.