DOC OTIS

iTrader: (9)

Need to know what head gaskets, studs/bolts, and tq specs you guys are using/running?

Ive got probally 2000 miles on my setup and just started dialing the n2o in and ran into a problem. On the bottle it was shooting coolant out the overflow. Did a leakdown test on it and both sides were leaking. Not sure if its a block problem? head gaskets? studs?

Im am using .053 Cometic's that are made for the Darton MID blocks and used permatex adhesive on the gaskets per MTI's instructions. The block is studded and I torqued the studs too 75 foot pounds.

Really curious what others are running and what is holding up. Ive got another set of Cometic's but a little leary of trying them again.

Scalpel

iTrader: (4)

Did you re-torque the headstuds after an initial break-in period?

I'm willing to bet the headgaskets are the issue in this scenario.

Scalpel

iTrader: (4)

BTW, just to clarify, you installed the heads on the shortblock, right?

DOC OTIS

iTrader: (9)

No I did not re-torque the headstuds. I wasnt aware that was necessary, and yes I put the heads on

cyphur

iTrader: (10)

Yea, ARP bolts/studs pretty much have a 3x torquing procedure. For some reason otherwise they have a tendancy to back off. That actually might be whats happened here. Otherwise definitely agreein with the head gaskets idea.

Scalpel

iTrader: (4)

Yep, cyphur nailed it. Sounds like the TQ backed up a bit and allowed the N20 to damage the head gasket.

Bear

iTrader: (1)

I get all my info from Steve at RED. He is the source of sources. Check in with him for help. He re did my whole setup. Good Luck.

Scalpel

iTrader: (4)

Bear, how's your motor running after Steve fixed it all?

hydfixer

I am putting my 427 together and have the same gaskets, what kind of sealer did you use? Can't remember by who but was told not to use sealer, did MTI tell you that? If so what kind? Thanks

Scalpel

iTrader: (4)

Also, have your heads re-checked for straightness to be sure they didn't warp any with the headgasket issue (assuming the headgaskets gave out).

slo-vette

I would recommend calling Cometic on the gasket adhesive issue. They told me to install them dry only.

DOC OTIS

iTrader: (9)

I'll have to look around and see if I can find the product I used. I know it was made by Permatex and MTI sent it to me, its what they use. Definitely going to make a few phone calls regarding the adhessive.

I appreciate the responses and the advice guys. Hopefully someone will chime that is actually running one of these blocks and keeping the gaskets on it.

11 Bravo

iTrader: (3)

Ditto for me.

Textralia

The permatex product you want is hyolmar...it comes in a tube and a spray...all LPE tt and 427's have this product on the cometic head gaskets Wash

11 Bravo

iTrader: (3)

Where do you get it, and why do you need it if Cometic does not recommend it? Not doubting you, but this is just something else that I am getting conflicting advise on. Want to do it right the first time lol.

DOC OTIS

iTrader: (9)

I've also heard conflicting advice. I tried it this way and it didn't work. Definitely hesitating putting it back together the same way.

Surely someone on here is actually running one of these motors? Id like to know what their using, not what is recommended. Sometimes I feel like I am doing R+D for some of these companies, lol

Textralia

you can get it at any major auto supply.... ive seen it done either way,and yes theres conflicting reports..... Wash

Stu'sWS6

iTrader: (3)

ttt for ya Doc!

Ben R

Steve @ Race Engine Development can answer any question you could possible come up with concerning the Darton MID Sleeves.

Scalpel

iTrader: (4)

You didn't re-check the torque on the head studs like ARP suggests after an initial engine heat cycling/warm-up. It may have very well worked if the torque was re-checked (assuming the tq was no longer the same as when you initially tq'd it on install).

The answer could be a simple as that.

I'd call Steve@Race and ask him what he thinks. He'd be a great source to ask