Headgasket on H.O.

MD-LUCKY

MD-LUCKY

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Whats the word on headgasket thickness for an HO (2001) motor?

I don't know how much is going to have to come off the head yet, but it is about to have new o-ring grooves..

I know the HO motors have a little higher compression ratio than the SOs, so I was considering going a little over stock thickness to drop that ratio down in the mid 17s.

What have you guys with HO motors done in the past? Where's the sweet spot on gasket thickness seem to be?

Thanks in advance!
 
You might be right.. For some reason, I had those numbers b-ass ackwards and switch around.

I thought HOs where 18.1:1 and SO's where 17.3:1.

I'll look it up.. Either way, what are folks doing to drop those HO numbers down to around SO numbers?
 
SO: 16.3:1
HO: 17:1

Dunno where I got those numbers from above. So, lets say I want to drop down to around mid 16s. Thoughts?
 
i would use a .020 over 12 valve gaskit. you have to cut some of the holes to match the 24 vlve one.
 
I would stay with the stock gasket unless you are planning to run massive amounts of boost or spray. Whatever you do remember that the higher the head goes the higher the injectors go out of the bowl.
 
TheBigNasty said:
I would stay with the stock gasket unless you are planning to run massive amounts of boost or spray. Whatever you do remember that the higher the head goes the higher the injectors go out of the bowl.
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thinner washers!
 
Seems I've either got to modify a 12v gasket to go over, or look at marine options.

I'm considering a .10 over marine. Need to find a good place to purchase original cummins equipment.. I'll make my decision soon.

Thanks for the help guys!
 
Go to cummins web site and look for a dealer close to you. I think rocky mountain cummins cover your area.
 
contact snedge on here, he is a cummins dealer and will ship parts to you out west. he has always been good to me.

i ran a .020 over 12v marine gasket on my HO with o-rings when I did mine 3 years ago
 
0.020 over will drop you close to 1 point if I remember correctly.

x2 on getting cummins parts thru Snedge...
 
Mike. I can supply you with a complete upper gasket set for your 24V and replace the stock gasket in the kit with a 12V modified gsk., any size you decide .010 or .020.
 
Diesel Freak said:
Why are you looking to lower the CR????

you will not like it!!! I sure didn't!!
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I'll second that. The .020 I put in mine took away torque and added smoke. That's about it. I would have put a stock one back in, but I got sick of yanking the head off. As long as nothing's leaking, that head can stay right where it is!:dead-horse-fast2::D
 
They ended up taking .08 off the head.. A bunch.

I ordered a .020 modified 12v gasket from Snedge. If any of you folks are reading through this thread and stumble across this, he is a heck of a nice guy and easy to work with.

The decision didn't boil down to compression ratio to be honest.. After they loped so much off the head I was a little more concerned about valve to piston clearance. Compression ratio should still be considerably higher than stock SO, but a little lower than HO.

Now I just need a set of twins to justify all this damn work.
 
I would just use a stock gasket, and check clearance valve to piston with ZERO valve lash to be sure.
 
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