RJC "bulletproof" headgaskets.


Signal 1 J-12
May 22, 2002
Are these gaskets as "bulletproof" as claimed? Anyone ever popped one without venting a piston(s) or DOTC?? Does the sealer that comes with them actually dry hard and is that just for water sealing duties???
Safety Valve

Would be better to blow a head gasket then hammering the bearing,windowing the block or DOTC.
Beings that Im the one that actually came up with that setup, I can answer most of your questions.

The sealer does dry but it remains pretty pliable. If you want something that dries a with less flexibility, I would recommend using the GE1200 sealant instead. One word of caution, tho, its very acidic so wear gloves if you use it because if it gets in your cuticles, it hurts for days. The sealant Jason sends out isnt acidic and works great.

In the beginning, I used the GM steel shim gaskets with this setup. They've been discontinued and mostly run out unless you get lucky and score some of them someone is sitting on them. The gaskets Jason designed to replace them seem to work well. I personally think double stacking them is still the way to go but thats neither here nor there.

Using the double GM steel shims, Ive only personally ever had two people blow the setup. Both times it took a large amount of boost to do it and it wasnt a simple pushing out of the gasket, the gasket exited the side of the block both times. Shane actually managed to blow both gaskets in half on his own car.

It's a tough setup.. as tough or tougher than anything else youre going to put on there. It's battle proven but like everything else, people that don't sell it will poo poo it.. there are a lot of good solutions out there these days.
The Black goop is made by 3M for this type of application to seal metal to metal. Ive had mine for a while and they work great.
I did manage to blow one out the sid eof the block this year, first time for everything I guess. Pre-stroker motor at high boost I never had one problem with them, and they were abused plenty....
i ran them on my tta.one time my alky pump went out and i lifted the heads and pushed coolant out the over flow:eek: but did not blow them.i had to retorque the head bolts down due to coolant and bubbles comming out of the over flow,but they were fine after that.
Blew my drivers side RJC gasket into the intake manifold. This was caused by a major knock event when the intake tube came loose after the MAF and before the Turbo (thus sucking a ton of unmetered air and running me way way lean). Of couse that happened at the top end of a 1/4 mile run. I was actually happy that it only blew the HG.

I've been happy with my RJC gaskets, I happily plunked down the money to buy another set after that incident and everything is still happy more than a year later.
I'm running them. I actually used the metal-flake spraypaint instead of the sealant.

Plenty of 20+ psi passes with absolutely no issues. Been on the car for 4 years or so.
i use them, they work good.....no issues. they work well enough for me to burn a piston up then finally melt a window in the gasket and block and head!
damn injector:mad:
a couple of us have been trying out the cometics with not as great of results as the RJC's so we will be going back with those on the next motor...
a couple of us have been trying out the cometics with not as great of results as the RJC's so we will be going back with those on the next motor...

I also used a set of them back in the day when the second gen style came out, I was not happy with them...I could never get them sealed up right. I'm now using the RJC gaskets...so far so good.
Gotta bring this back. So is it true? Will these seal it up soo good that I'll burn a valve or piston first?
The sealing is only as good as the clamping. Clamping comes from the fasteners. There aren't enough to prevent head deflection with a stock block. If you're hurting head gaskets then you have other issues

Using the RJC steel shims on aluminum heads does not sound good due to possible galvanism and the gasket hardness compared to the cylinder head deck.