3FE heads on 2F head (1 Viewer)

[Godwin]

An unmolested intake. This is the underside and one corner needs to be ground down to eliminate the interference with the 3FE exhaust manifold. The white material in the holes is dirt dobber mud .

The is the manifold I've worked over and you can see the corner where material has been removed. A fair amount has be taken off.

Before actually mounting on the 2F I'm planning on dry mounting the manifolds on a head to check final clearances.

 

[Klonky99]

So those holes are just where the exhaust manifold mounts to the intake and they'd be useless now right?

 

[Godwin]

Yes, with the 3FE exhaust no need for those bolt holes.

 

[LAMBCRUSHER]

Godwin, looks like your more careful approach has left you with potential to use on a 2F manifold, maybe. I took off more material than that, but because I didn't feel like taking my time to clearance- just made a cut to be done with it. Good Work! I'm still on the fence about weather to take off the face of the exhaust flange, or to grind down the back of the where the bolt come up against. the face milling would net a cleaner look, but would be alot of material to take off and leave potential room for warpage...

 

[Klonky99]

What are you doing for your down pipes? Are you custom fabbing them or do you already have the 3fe down pipes?

 

[Godwin]

I have 3FE down pipes.

I'm going to add washers, or 1/2 washers, to the intake to build up the difference between the thickness of the 2F intake and 3FE exhaust. I'm hesitant to have the 3FE exhaust milled down plus I don't know of a good machine shop in my area. The good one went under a few years ago.

 

[cruisermatt]

I have 3FE down pipes.

I'm going to add washers, or 1/2 washers, to the intake to build up the difference between the thickness of the 2F intake and 3FE exhaust. I'm hesitant to have the 3FE exhaust milled down plus I don't know of a good machine shop in my area. The good one went under a few years ago.

Make sure you use the Remflex gasket. Even though you are accounting for the differences I'm sure there going to be some irregularities that the thicker gasket will take up.

 

[Klonky99]

The face that mates to the head shouldn't have to be milled, just around the bolt holes I thought

 

[cruisermatt]

The face that mates to the head shouldn't have to be milled, just around the bolt holes I thought

What? No, just a few of the bolts don't line up. Nothing critical.

 

[BGarcia88FJ62]

@Godwin How are things progressing with this mod.

 

[Godwin]

@Godwin How are things progressing with this mod.

Slow. I don't expect to have it completed until October. I'm on the road a lot through the end of the month plus I have to rebuild my t-case in the next week. I have all the parts I need, just need the time, but I also have to track down a good muffler shop to finish out the pipes. I'm planning on cutting the Y-pipe to avoid the routing under the frame.

 

[BGarcia88FJ62]

Slow. I don't expect to have it completed until October. I'm on the road a lot through the end of the month plus I have to rebuild my t-case in the next week. I have all the parts I need, just need the time, but I also have to track down a good muffler shop to finish out the pipes. I'm planning on cutting the Y-pipe to avoid the routing under the frame.

Sounds like you have a plan put together. I'll keep my eye on this thread really curious to know if how well it performs.
would love for this to be an alternative to headers. Sourced a 3FE exhaust Manifold looking for a 2F intake.

 

[60 toy ota]

Let me know if you want pics of my routing (2fe), had a shop do it and it should have rolled out of the factory that way

 

[BGarcia88FJ62]

Let me know if you want pics of my routing (2fe), had a shop do it and it should have rolled out of the factory that way

Sure post'm up no such thing as too much info.

 

[Godwin]

Minor thread bump. I made some small amount of progress today. Rough measurements flange thickness is that the 3FE exhaust manifolds are 15 mm thick and the aluminum 2F intake is 10 mm thick. My approach is to cut in half OEM manifold washers and stack two 1/2 washers on the 2F intake to increase thickness. The washers are ca. 3 mm thick and this give me a flange+washer thickness of ca. 16 mm so I'll have to sand down the washers to match the 3FE flange.

Progress today was cutting 6 washers in 1/2 and JB Welding one set of 1/2 washers to the intake. Once the JB has set up I'll JB on the other washer set. I don't know if the the JB will hold up to the heat but with 1/2 washers sandwiched between the manifold flange and a whole I'm not concerned about that.

 

[LAMBCRUSHER]

that sounds like a good alternative to the grinding of the exhaust flange. Post up results!

 

[LAMBCRUSHER]

the jb weld will do fine.

 

[Godwin]

Forgot to add that I went with OEM washers because I knew they would be the correct inner and out diameter and thickness would not vary. I've seen too many hardware store washers that within the same bin were of widely varying thicknesses.

 

[60 toy ota]

Sure post'm up no such thing as too much info.

Better late than never. I really like where they put the 02 sensors, replacing both is a 10 minute job (although that's not really applicable here...)

 

[Bluegrass40]

Just found this thread. I have a '78 40 and am planning on replacing my header with a 3fe manifold that i picked up about a year ago. I'l be watching the thread to see the progress.

Right now, I'm looking for the documented bold pattern for the exhaust manifold. I want to make up a temporary plate to mount the exhaust manifolds to so that I can work on the y pipe layout outside of the truck (I need to keep the truck running right now and don't want to remove the header etc to get the measurements... Anyone have these dims?