What headgaskets will hold up to 20psi, also is 20psi enough to lift the heads off the engine block? What's a safe number for boost levels before you have to drill out your block to accommodate bigger head studs?

 

o-ring the block

 

I wouldn't do that. Blowing a head gasket is a safety valve. When the headgasket can't blow, the bottom end will.

Rob

 

Is true is a safety valve, but if the gasket blows there's a good chance that the combustion escaping thru the gap that the blown head gasket leaves will eat-up the engine block and the head, It happened to me once, and that's a bye bye to both the block and the head. I strongly recommmend the use of head studs when running high boost.

 

I would stud the heads also or at least a good set of bolts(ARP). With 5 bolts per cylinder and a stock or Fel Pro Perma Torque head gaskets I dont think there should be a problem running only 20 pounds of boost, with a proper tune of course. Keep the compression low and the octane high, and watch for detonation of course

 

if your running 20psi on a bottom end that cant handle it whats the point?

 

It's a safty valve if things, or the tune, go wrong. Even the best bottom end will come apart if detonated bad enough.

 

ok at what PSI dont you have to drill out the block for bigger head bolts?

 

You dont need to re-thread your block in order to put studs.

 

I dont think you need to go with bigger bolts(preferably studs anyway)no matter what PSI your running.

With the buick V6 it's not bigger studs that help but rather more studs. In a stock block we have 4 bolts per cylinder, to increase cylinder seal the Buick motorsports stage 2 blocks have 6 bolts per cylinder. A smallblock has the advantage of 5 bolts per cylinder.

The best thing you can do to keep the headgaskets in the motor, at 10psi, 20psi, or 30+psi, is a proper tune and extra attention when assembling the motor(like making sure the deck and head surfaces are perfectly flat, clean, and dry). I'll say it one more time, a proper tune will do more for keeping the headgaskets, and motor, together than anything else.

Steve

 

fel pro loc-wire gaskets and head machining

 

The heads pictured above appear to be o-ringed? Do those felpro gaskets have a copper ring in them to sit in this groove?

How do those straight copper headgaskets work? I seen them in parts catalogs and wasn't sure if they were worth $85.

 

I got the FLATOUT RCC Coated Copper gaskets and had www.fowlerengines.com put in O rings in the block and recievers in the head. My option was the Felpro wire LOC or the Flat out set up which was suggested stronger. The RCC coating suposedly lets me run on the street. You can feel the coating on the gaskets , a type of clear silicone like laminate.They are reuseable as well.


Normally the copper gaskets tend to leak a little anti freeze on the street making you have to check the oil but the new rcc gaskets put a stop to that suposedly.
Pics here of o-rings , heads , and block can be seen here
http://614streets.com/Nova.html

I noticed Summit now carries the FLAT OUT Gaskets.

http://www.flatoutgaskets.com/
Good reading here
http://www.flatoutgaskets.com/gaskets/techtips.asp

I think alot of the composite gaskets out now are pretty dam strong, fel pro race and cometic etc. I would think the main issue to run 20 psi would be to make sure the heads and block deck are straight and very clean and run studs. The rest of the engine obvioulsy needs to be strong and then tuned well before going nuts with the pressure.

 

no they are reciever groove cut to fit a felpro part # 1045 The 1045 is just like a regular gasket but it has an oversized fire ring inner wire that fits into the machined reciever groove. the wire is made from stainless steel. If your machine shop has never done this before, find a new machine shop. the gaskets are available from vendors of felpro high performance gaskets. They are not officially O-ring. O-ring would be the next step for me and involves some compromises of its own.

O-ringing is described well above in 614Streets post with the copper gasket. The copper gasket is not used on its own to achieve the fire ring seal but is pretty much the most severe setup there is. Most cars that run O-ringing are either ford or have found it is the only thing that works in thier massive cylinder pressure application.