Has anyone swapped an FE for a 400? Will it work with a NP-435? Would a C-6 be better or less involved?
Beers to all

 

Yes it will work with the NP435 - you just need the right bellhousing.

Why?

 

If it's a stock 400 you have laying around and this is a cheap repower, keep the FE.

If it's a 400 rebuilt with some compression and a decent cam, you might be on to something.

FWIW I would not go through the trouble to change from the FE to the 400. The FE can be made to do more than the 400. The FE already fits so I would not be spending money on mounts and bells etc.

ymmv.

 

Back in 77 I purchased a new 77 T-Bird and it had a 400 2 V and it ran really well and got good mileage. The only problem I had was the crude computer would malfunction occasionally and the car would have to sit for an hour or so then it would go! After that issue was resolved I put 70 K on it then sold it to a friend who drove it for a long time until he got T-Boned in an intersection.
I always thought the 400 was a decent engine as the heads were similar to the Cleveland heads and flow real well stock, however, not quite the sewer pipes like the Cleveland heads are.
Other than there is a lot of aftermarket goodies and it is a more modern of an engine and maybe easier to find parts.
I had a lot of head work done on my Bird 390 yeas ago when I rebuilt it. Lot of work to get them to flow, install hardened seats, sodium filled valves and a 3 angle valve job and other head and valve train work. I installed a Cobra Jet cam from a 428 and a Holly 650. The machine work was expensive.
400 heads should come with hardened seats and decent valves for unleaded gas. Shave them to boost compression if needed but at least a 400 should run OK on pump gas we get nowadays.
I'm looking down the road when you need a valve job and it cost a fortune to update the 390 heads.
The 400 4V Edelbrock is coming out of a Torino

 

Not much in the way of pistons for a 400, aside from the dismal mid 8's CR stock dished "teacups". Yes, there are some available from tim meyer, but they aren't cheap, and generally only .030 over.
The 400 could have been a great engine, but it came along at the wrong time, and was smogged to death.


Fitting it into the truck will require 77-79 engine mounts and frame stands for a 351M/400. Along with the correct 400 flywheel and bellhousing to mate up to the NP435.

I had a 78 F150 with a 351M. Wasn't a bad cruiser, but had no guts when it came to towing. A 300 pulls better than that dog did. I seriously debated swapping in a 390, but sold it and bought a 65 F100 with a warmed up 390. That 390 would accelerate faster towing a loaded trailer (stopping was another story....), than the 351M did empty, and they both got about the same MPG.


If the 352 is in decent shape, I'd spend the money getting the heads prepped for unleaded (if not already done) and swap in a mild cam. Using car 352 pistons, rather than truck pistons, should give a decent bump in comp ratio while still allowing for pump gas.

In my opinion, the FE is twice the engine compared to a 400. And I don't just mean in wieght.......

 

Did you know you can bolt on a set of 4V Cleveland heads and get 9.6:1 as long as you use the rest of the right parts for the valve train?
Now you have a set of heads with sewer pipes for intake and exhaust. Nice roller cam and great big Holley double pumper? What happened to the gas mileage?
Oh well, what the heck!
See how easy it is to get carried away?
Guess i should leave it stock...

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