Just ordered dual efi exhaust manifolds and an offy c intake. Was wondering where I find the gaskets to buy as I bought both used.

 

The gasket should be any standard 300 intake/exhaust manifold gasket.

Although, a Mr. Gasket 260 is a step up from what you can buy in the auto parts stores.

 

The gaskets come together? Km still a newb in the 300 world haha

 

Sure do.

 

Oooo..now I'm enlightened. I notice u have studs on your block..I believe ill just have bolts to line things up. Will this be hard.

 

It's just more of a pain. It's how I put mine on the first time. I didn't like it, but it wasn't something where I was pulling my hair out.

On the stock 1bbl setup, the entire manifold was one solid piece. So, you could put it on the guide pin and it would 'hang'. Put another bolt on the other end, and done. It was in place. After that you could just take your time with the rest of the bolts.

On the stock EFI setup, the head had 16 bolt holes instead of 13 like the carb engines. That's what the 3 extra loops are for on the EFI manifolds. They had three pieces to install instead of one (intake, front exhaust, rear exhaust), so being able to bolt the exhaust manifolds in place with bolt holes that weren't shared with the intake really helped a lot.


When you put the EFI manifolds onto a carb'd head, the guide pin only works on the intake, and the exhaust manifolds don't have the extra bolt holes to hold them in place, so you're almost completely on your own balancing these three manifolds in place AND getting the bolts in. When you use studs, you can sort of 'hang' the manifolds on them, tighten some nuts down, and they'll slowly stay in place. When you have just bolts, it's a bit more difficult.
Not impossible, just an extra layer of frustration.

 

So when I'm specifically finding a gasket..I need to get the efi setup ? The 13 to 16 bolts won't mess anything up?

 

You don't need to worry about that at all unless you have one of the rare carb'd heads that have 16 bolt holes. A few members here have them and they're usually an '86, but maybe an '85 has them. If that's the case, you can simply use them to your advantage and in that case, get an EFI gasket so it has the 16 bolt holes.

If not, don't worry about it one bit. Just get a regular 300 intake/exhaust manifold gasket set. It won't matter.

The only thing you'll have to do when you get your exhaust manifolds is a little bit of grinding. Often, one of the extra bolt hole loops on the EFI manifolds (one of the extra 3 I explained above) binds with a carb'd intake and you'll have to grind it completely off. No biggie, but is completely necessary.

Also, sometimes, the EFI manifolds stick out a little too far and you'll need to grind a little bit of metal off until they fit together nicely. Be SURE you do this before installing your intake or you'll break mounting tabs off and ruin it.






Again, not hard, but very necessary.






.

 

This'll show you which one you need to remove:

Three bolt hole loops in this picture:



Only two in this one:

 

The bolt loops aren't by the bolt holes on the gasket face like I thought haha

 

When u say bolt looks..are you saying what the bolt to the head goes into or something entirely different? Sorry..I just was kinda unclear even with the pics haha

 

On the bottom pic, see how only the far right stud is going through a bolt hole? That's the only one that does that (and it's just like the stock log manifold).

The other bolt hole loops sticking off the exhaust manifolds aren't used (and no stud is going through them). Those are extra loops for the EFI head that help in installation.

 

Man..I still feel stupid haha ok..I seen the very far right with the bolt and nut on it..from the top pic I seen the same hole still attached. What exact hole do I need to grind off? I do apologize..

 

No prob.

On the left (rear) manifold, on the rightmost runner. You can see in the top pic that it has a loop on it. On the bottom pic, it's gone.

Either way, you should be able to tell immediately the second you try to line your EFI manifolds up with the Offy, or even stock, intake.

 

O thank goodness we have a breakthrough! Haha I FINALLY see what you mean. My coordinates were all messed up. Alright.. moving on..how much would I grind off?