In Case Anyone Cares....The Cometic Leaks

[rico05]

Yep. It does. So this weekend my Felpro will be in, and I will be coppering it up and nice and sexy and hoping that it will work. More than likely, I will be getting ARP head studs ($$$ allowing) so that there are no weak points in my install. Sucks, but oh well. Live and learn. She is drivable, but every time I boost or revv a lot, she gets hot, and she needs a refill of water every day. Argh.

[c-rad]

That sucks man. I am hoping mine doesn't leak. It better not!

[TurboFortysx]

That sucks. If mine leaks there will be hell to pay!! I have the headstuds on mine now so we will see...

[rico05]

Well Chris, you did your right and had your block decked and your head milled.

I "plan" on a full factory spec (a little head porting may or may not be in the plan) rebuild done by SGP http://www.sgpracing.com later on in the fall. They are legendary for thier VGs so I think they can do a CA pretty well

[c-rad]

Well Chris, you did your right and had your block decked and your head milled.

I "plan" on a full factory spec (a little head porting may or may not be in the plan) rebuild done by SGP http://www.sgpracing.com later on in the fall. They are legendary for thier VGs so I think they can do a CA pretty well

I bought a bunch of stuff from Kyle at SGP back when I had my Z32. Good place!

[boost_boy]

The one I just Overboosted's car was letting penetrant out before the engine ever saw oil. So I check the torque specs of the head studs and they were tighter than recommended. Needless to say, it did not leak after we test drove it. As a matter of fact, no leaks (Thank god). I'm going to be putting mine on today if UPS brings it early enough. We'll see what happens then.

Dee

[Shift_Tommy]

a quick noob question, why do mechanics spray copper spray on gaskets?

[c-rad]

a quick noob question, why do mechanics spray copper spray on gaskets?

If you don't resurface the head and block, there are little peaks and valleys on the surfaces (no matter how good you are with a scraper). The copper spray fills in these gaps to create a good seal.

[rico05]

Yep. Spray it on, and hurry up and get the head torqued down and it will act like a high temp adveasive. A can is like a $5 insurance policy.



I hope to be back full boosting in the next few weeks. The funniest thing about all this is in my hurry to get the HG bought, I bought the Cometic trying to get something better than stock (the usual ideology for all of us I assume) and in the end, it just ended up making for more of a headache!!

I think this time I may do a full pic tutorial since I actually know what I am doing

[float_6969]

I put mine together with a felpro, stock style gasket and copper spray. I'm using ARP headstuds, and this is a High compression CA that has seen up to 18psi and never batted an eye. I'm sure the Cometic is a good gasket, and if it had been available at the time I built my motor I would have put one in, but it wasn't so I didn't

[Kouks]

Sorry to hear that it leaks rico, especially after all that work. good luck on the felpro.

[rico05]

No biggie as I kind of expected it. I hope the Felpro does a better job.

[capowered240]

What all do you spray it on? Both sides of the gasket.

[rico05]

Yep. Spray it on, and get the head on quick, before it dries all the way. FYI, it is on the spray paint isle in O'Reilly and with the oil funnels at NAPA.

I also got eh hook up. Long story short, a buddy of mine got me the Felpro at cost. So instead of $70, it was $30. Head should be off again tomorrow night, barring any major issues (which I know will occur)

[capowered240]

Alright thanks. Those felpro gaskets any good?

[rico05]

Apparently, since there are a few folks on here running them.

[nocwage]

What happened to all those Nismo head gaskets people had bought?I know they weren't cheap but are they still available and were people happy with them? A guy I know just had his cometic on his 4g64 die on him as well.

[float_6969]

Just to re-iderate, you HAVE to have the head AND block, resurfaced if you are going to put a Cometic in. They will NOT seal if you don't.

[Neejay]

Head should be off again tomorrow night, barring any major issues (which I know will occur)

Always...there is always SOMETHING minor and/or stupid that goes wrong, lol.

So if I werent planning anything crazy (boost/hp wise) then a oe type Felpro gasket + copper spray gasket would be ok?

[rico05]

Get some ARP head studs as well. The ones you want are the Mian Studs for an SR20DET. The ARP part @ is 202-5402, and expect to pay ~$100 for a set. I am doing this head gasket, then here in a week, I am ordering the ARPs and swapping them in later on. Common idea is CA head bolts are not torque to yeild, and should last about 2-3 removals/reinstalls.

[XTCshri2222]

I'll be useling feldpro on my rebuild here some pix of the Feldpro gasket for you all.

[kota2240]

i just wanted to say that my cometic is leaking. I had the head redone but not the block. I guess im kicking my self in the *** too.

[rico05]

I was really impressed with the quality of the Felpro. I am very interested in seeing if Chris has luck with his Cometic after his monster build.

And as long as I can get someone to help me lift my head off (it has been ready to go since Thursday) I should be done Monday night or Tuesday.

[nismoplsr]

Just to let you guys know i have been running a felpro for 3 years now with reused stock head bolts. No problems yet. First year it was 14 psi on the stock t25, then a year of 18 psi on GT28RS, i am now running 22 Psi daily with the GT28RS and the Felpro gasket.

[boost_boy]

Just to let you guys know i have been running a felpro for 3 years now with reused stock head bolts. No problems yet. First year it was 14 psi on the stock t25, then a year of 18 psi on GT28RS, i am now running 22 Psi daily with the GT28RS and the Felpro gasket.

With the right fuel and timing, you can do this all day long.

I still can't understand why you guys are having issues with the cometic gaskets. I have opened-up an engine that I built, did some minor repairs, re-used the same cometic gasket, and still no leakage. Needless to say the repairs were a success, so expect to see a 450+whp CA posted within the next couple of weeks or so.

To those who plan on using a cometic gasket, you must make sure your block's deck is smoothed out and free of warpage. If your engine hasn't overheated, be sure and move all pistons half-mast, and stuff each chamber as much as possible to prevent abrasives from going into the cylinders. Make sure you scrape all the old H/G material from the block's deck and any rust or corrosion as well. Next, using 400grit sandpaper with your hand and without applying too much pressure, commence to sanding the deck evenly until the area has a smooth shiny finish. Be sure and check the cylinders to make sure there isn't any abrasives in there. This is more of the do-it-yourselfer way, but the best way to get a good finish is to remove the block and head and get them decked or resurfaced by a competent machine shop. This works for me, but may not work for you, so don't follow my lead.

Dee

[rico05]

Good info Dee. I was worried about trying sandpaper, but I am going to give some 800 grit a shot tomorrow. For a Felpro gasket tho. I will hang on to the Cometic for my future build.

EDIT: Any tips for the head? Is B-12, a razor, and elbow grease really the only way, or you have any other safe tricks?
Modified by rico05 at 2:27 AM 4/17/2006

[TurboFortysx]

You can also use a fine 3m pad that fits on a dremel tool. It worked really well for me.

[rico05]

800 grit, a soft hand, lots of B12 and one of the nice wash cloths from JC Pennys that my mom bought me showed me that in my rush of reassembly last time, the head was far from clean. There was a LOT of gunk still on there. I also checked it with a straight edge, and made sure not to rub perpindicular to the bore. I think that between the forgiving Felpro, the copper adhesive, and proper head stud torque (anyone remember the bolt I left loose? LOL) should see this as a long term fix. Tomorrow we shall see.

[Neejay]

so do you think that was the problem?

[Fenvy]

hey rico, quick question about the arp, is it the main stud that needs shaving or the head studs?