3100 gasket on 3500 head

[SappySE107]

I found a 3100 gasket and took some pictures of it on the 3500 head.

The fire ring overlaps the combustion chamber on the intake and exhaust areas. Not much, certainly not the width of the fire ring but I don't think this is a good way to be. I am not sure what will happen if you use a 3400 gasket on a bored over 3100.

[SappySE107]

I used some clay to form around it and its .025" overlapped.

[Chris88CL]

I want to see a 3400 gasket on the 3500 heads.

[SappySE107]

I have a 3.4 DOHC gasket, which is the same thing as far as bolt pattern and bore goes.

[1988GTU]

Any for a 3.1MPFI block with 3500 swap combo? Or is that very much the same for the 3100/3500?

[SappySE107]

Thats the same thing as 3100. 2.8/3.1/3100 use the same bore.

[Scott_68B]

This is excellent information. Do you think that we're better off not going with 3500 heads on a stock 3.1/3100?

-- Scott

[SappySE107]

Correct. 3400 top end is the limit for a stock 3100/3.1/2.8. Going .060 over might fix the problem and using 3400 gaskets. Im not entirely sure on that though.

[1988GTU]

Find out!

[3400-95-Modified]

Pic of a 3500 head with a 05 3400 gasket...

[MY91GT(Z)]

good pix and for those that want to know whats best to use on their swaps and y they r the better methods so that u dont have to do a build twice

[3400-95-Modified]

Well rule of thumb is to always use a head gasket that pertains to your bore, so your sealing ring fits the cylinder, if you go larger you could run into some issues, and obviously if you go too small for the cylinder head you could also run into some major issues.

[Will'sFiero]

So what are the actual fire ring diameters of the 3100, 3400 & 3500 gaskets?

[Scott_68B]

Bringing this back from the dead out of curiousity, what issues would you run into if you used a 3400 head gasket on a 3.1/3100 block w/3500 heads?

[ForcedFirebird]

Bringing this back from the dead out of curiousity, what issues would you run into if you used a 3400 head gasket on a 3.1/3100 block w/3500 heads?

The chamber will still overlap the deck.

EDIT: It also appears the valves would be shrouded by the cyl wall.