hello all, im currently building my newly aquired 95 12v and had some questions. im going to o-ring the head and stud it, but i don't know which stud kit to go with here are a few i've seen, A1 12mm, ARP 12mm, and haisley 12mm, which is the best? also what head gasket should i use, i plan on twins in the future, since im o-ringing the head is there a certin head gasket to use? thankyou for any help.

jason

 

The arp's are good choice. How much boost your gonna run? If your gonna exceed 70psi, run a copper head gasket. How much advance you running? If you run lots of advance, go the copper head gasket. The bad side of the copper gasket is that they slightly leak coolant and are a bit messy. I'm running a stock 2gen gasket but I hardly exceed 65psi of boost.

 

well for a single turbo i probably won't pass 45psi, but my future twn set up i plan on pushin 70-80psi, right know the 95 12v is out of the truck and is stock so i haven't messed with the timing yet, also i have heard about using a marine haed gasket, are they good for 70psi?, and where can i buy a copper head gasket? should the haed gasket be a bit oversized, like .10 over? sorry about all the questions, but i don't want to build this engine twice. thanks again for the help
jason

 

I like the 12mm ARP studs and the marine headgasket using o-rings. This setup holds very reliably to over 80 psi. On my old truck I saw over 100 psi on this setup with no failure. The trick is to do the o-rings correct and spend the time torquing the head. Done correct this is about the ultimate street setup. The A1 and Haisley studs are the same.....

Doug Smith

 

If it aint leaked yet I would just do a re-torque or stud it and go.

JMO...

 

well i appreciate all of your opinions and will probably go with the marine head gasket, since the copper ones have more of a tendency to leak, but where can i buy a marine head gasket and should i get it a size larger, like .10 over?
jason

 

come on guys i know that somebody knows where i can buy a head gasket from.

jason

 

Cummins.

3283339 is the .020 over gasket
3283337 is the .010 over gasket
3283335 is the stock size.

Doug

 

And the ARP studs are on sale over at www.naparts.com right now

 

So if you use a thicker head gasket (.020) and you only have to remove .007 off the head to true it up, that makes the head sit .012" higher than stock. Do you have to re-shim your injectors to adjust for the change in location? Does that cause any issues with compression?

 

You can get differant size washer's for the injectors and bring it back close to stock.

 

Good questions. I've been told that my f-1 sticks are designed to work in the typically used range of gasket heights. I too am curious as to the effect of lowering compression a bit through the hg and if a thicker gasket be better for guys like dogin and me with the higher compression eth's.

In general terms, how does a bombed ctd respond to lower compression of a .020 gasket?

 

My truck has difficulty starting at cold ambient (below -20) when not plugged in. Sounds like only three cylinder are running. Tons and tons of smoke. I've heard that dropping the cylinder pressure abit helps with cold start but it might be a tall tale.

 

thats defenetly a tall tale. it does just the oppisite.

 

We use only the .020 over gaskets on all headwork/rebuilds we do. The compression drop is small and the plus side is improved valve to piston clearance. There isn't any cold weather start problems either.

Doug