What are the differences between 460 manifolds from a 1990 F250 and a 1994 F250? Is it only the EGR tube locations and styles or are the port sizes and bolt patterns different? And while I'm asking, are there differences in the lower intake too?

 

Nobody? Nobody at all?

 

I believe the 94 has F3TE heads which I believe has slightly bigger ports so I would think that the lower intake and manifold would be slightly bigger too however I am not sure.


I am curious though on what others say on the intake manifold as I have both a stock 91 intake and one with a F3part number which I believe is off a later 460 and curious which one I should run on our 91 460.
Trav

 

My hunch exactly. It's like you read my mind!

 

I don't know brother. This is the only 460 I have had.

 

all the part numbers for efi 460's are the same.

 

^ there ya go.

 

That's for the intake, right? I couldn't find any concrete info on that. Several places said all will fit, some said 88-92 and 93-97. So confusing.

I have just about figured out that the exhaust manifolds do have different ports for the EGR, but still don't know on port size and bolt pattern.

 

All EFI 460s have the same bolt pattern for intake and exhaust. Both of which are completely different in pattern and spacing from the earlier carb'ed version.

 

This is all EFI stuff, so good. So any intake and exhaust manifolds I decide to use will work, as long as the EGR issues are handled.

I'm gathering up parts for a repower for my truck. I'm going to do some porting on the intake and cast manifolds. If the exhaust manifolds don't turn out to suit me, I'll go with headers.

 

I couldn't get the EGR and AIR fittings out of my manifolds. I just welded them up.

If you are going to do all that work, maybe try to find a deal on shorty headers?

 

EGR fitting is just something I will deal with. I will get JY ones that don't have the AIR fittings cause them things are a real PITA! If I end up going with headers, I'll go with long tubes. If I'm going to go thru the trouble fitting headers, it's going to be for the maximum gain. But I really want to try ported manifolds. EXTRA WORK+DIFFERENT=FUN, right? Maybe?

 

The real gains are on the exhaust port and larger exhaust valve. Any other work on the intake side is very little gain IMHO. Porting manifolds is a waste of time.

 

I have my eye on a set of heads that have larger ports and valves. I'll get them soon. Maybe just a little clean-up on the intake. Not enough to gain on the exh manifolds to make it worth it? Or are they just made wrong for flow?

 

Just port match the intake to the heads. Polish the combustion chamber and exhaust port. Not sure how much larger valves you can go with.