Daniel Mitchell

I'm sticking a set of Pro Topline aluminum heads on my '70 Nova (old style LT1) and need a little help to make sure I don't screw it up. What should I torque the heads to and should I do it in steps to arrive at a certain lb/ft? I'm using new ARP bolts if that matters.
Also, what should I use on the bottom bolts to seal in the water passages? Will pipe sealer like what a plumber would use work? I've heard that's what to use but it never hardens so I don't see how it seals.
Oh yeah, should I just torque them from the inside first and work my way out? I've got a Haynes manual that will probably show the sequence though. Thanks for the help!!

Z28SORR

The torque spec. is for the bolt not the head material. Because you are using ARP you will need to get their specs. And they will recommend a sealent to use also. Try their WEB site or call them.

Green95Z28

Yea, stock torque specs and the stock sequence is what you want to do. You could go a bit more on the torque but not more than about 5 foot pounds. Although some may disagree I always start my torque at like 35 then go in steps of 10 foot pounds until I arrive at 65. Then once I have it all finished and I fire the car and run it for a day or so then I re-torque the heads , many people say you don't need to do that but I just do it for good measure, and so I can check everything.

HeavyChevySS

hey green, nice collection bud !!


1993 Z-28 13.22@103 1.80 60'
1995 Camaro Z28 13.3@104
1968 Camaro (482ci 705hp EFI)
1969 Chevelle SS 396 12.19@110
1963 Nova SS 10.554@125.4 1.37 60'
1973 Chevy Vega 327 CI (hasn't run yet)
Front Motored A/Fuel Dragster 6.65@202 1700+RWHP
2004 Corvette Z06 13.00@114
2004 Corvette C5 13.74@103
(New motor for the nova and 93 soon)

couple questions..

the Z06, I don't think you have drag radials on that do you?
I would def. get some and drop that time down.

the velle, whats done to it as far as power?
I ask because that is almost the exact 1/4 times I am expecting from mine this year. my 383 will prolly put 360 - 390 rwhp to the ground.


thanks

Damon

Torque will be the same or very close to stock spec- 65 ft/lbs.

Do them in steps- 35, 45, 55, 65. Go from the center out in a spiral pattern, or follow the manual's recommendations. The exact order isn't hyper critical.

Sealant is at your discretion. It does not need to be a hardening type sealer. I've used all sorts of goop and never had a leaker. Permatex non-hardening, Gasket Shellack (nasty brown stuff in a little brown bottle), even simple anti-seize compound (the grey stuff). You don't want to glob it on the threads. A thin coating will do just fine. It just has to be BE THERE, basically, not much more.

You MUST run a thread chase through ALL of the old block threads before you install the heads. Failure to do so will not allow you to get anywhere close to an accurate torque on the bolts when you reinstall the new heads.

You MUST use the little washers that come with the ARP bolts if you're using them with aluminum heads. They prevent the bolt head from galling and digging into the soft aluminum head when you torque the bolts down. Put just a little motor oil on the washers before you install them just so you're not tightening the bolts down dry metal against dry metal. Again, for accurate torque settings and all later. The beveled inside edge on the washer goes UP towards the bolt head. The flat side goes DOWN against the head.

Go slow, take your time. Do it right the first time. You'll go buggy running a chase through all the threads before you're done but it's a critical step.

A little old-school trick for you, too...... after you have done everything right and everything's torqued down correctly let the engine sit overnight. Run the head bolt torque AGAIN at 65 ft/lbs. You'll be surprosed how much further they move, jsut from the gasket compressing down overnight and settling. NOW it's properly torqued and you won't have any problems with it later.