I have a 1990 f-250 4x4 with 90,000 mi. automatic trans. pretty much stock. I am second owner I inherited it from dad so I know all the history of the truck. My question is : will a 1970's 429 swap out with the 1990 460??? I have a built 429 putting 450 hp. and I am hoping it will swap out. The 460 is EFI and I know I will have to swap the EFI parts over. I just can not stand the gutless 460 that is in it now and the 8-9 mpg. Thanks

 

The block will swap in, heads not so much...your efi intake won't fit the old heads and the SD computer and EFI probably wouldn't run with the cam you have in the 429 anyway if it has overlap.... Of course you could convert the truck to a carb and put your complete 429 in...unless you have an E4OD auto then you'll be needing an independant trans controller as well..

 

EFI heads have totally different ports than your 429 so, no.
Neither the intake or the exhaust manifolds will mate up.

You would also have to find a way to make the front dress work and change to a rear sump oil pan & pickup.

The motor mount location and bellhousing pattern are the same.
The 429 was internal balance though so you would have to find a zero balance flex plate to mate to your transmission.
And if an E4OD, run a controller like a Baumann.

I've seen conversion plates to put a carb on an EFI engine at Price Motorsport, but not the other way around.

Edit: I see I'm late to the party on this one,

 

i see in your sig you say you got a 5spd correct? if so swapem youll just have to run a carb... then you gotta regulate your fuel pressure from 30+ down to the 7psi range

 

The 5 speed is in HIS diesel truck, the question is about the 1990 Automatic he inherited from his father....

 

I made a swap like this although not on that new of a truck. I had a 429 CJ and a super sharp 79 f100 explorer. Truck was an original 302 a-t with air. To make the swap go easy I bought an 78 lincoln with a 460 for $200 bucks. I used all the engine accessorie brackets from the lincoln to make the ac,ps and all work on the 429. Used the tranny out of the lincoln and shortened the lincoln driveshaft and used it in the truck. Only thing we did to the tranny was add a shift kit. What a sweet ride. I think if I was you I would do about the same and use the tranny out of the lincoln to get away from the electronics and you would have a fun ride then.

 

Damn i completely screwed up there, i see now in the original post it says Auto, but either way fuel psi gotta be regulated down to 7ish psi

 

He cant get a tranny outta a Lincoln... his is 4wd so hed have to run a divorced transcase, its auto then he can do what Al said or he needs to find a C6 or standard to swap in

 

Can't be a deadhead regulator either, needs a return line...

By the time you swap to MAF, get a shift controller, FPR, new exhaust, ect... you'd be time and $ ahead to just build the '90 motor.
(stroker, compression, bigger injectors and a strong SD friendly cam)

Those ports flow better stock than any stock carb head anyhow.

I don't know about in Seattle, but you could never get past smog to register it here.

 

Have to ask... why is the current 460 "Gutless"? I have a 460 in my Dump, w/ 410 gears that has more than enough ***** to haul anything I put in the bed. I've owned several 460's over the years and other than MPG's, I have no complaints with any of them.

 

Deffintally would have to have return line to go from 30+ to 7, and i disagree on the ports though a good set of C9's or Doves will walk all over a newer set of heads....


in NC aslong as its older than 96 it dont matter cause it dont go on the computer that way

 

Okay, I should have said D3VE's, E6TE's (heads that you'd find stock on ANY truck...)
Not CJ's, SCJ's, or PI heads - which only came in cars.

 

....... I see your in Seattle, drive down to Tacoma to Reincarnation and talk to Scott..... He's forgot more about making power in the EFI 460s than most of us will ever know... Heck you can buy ported efi heads and intake from him that will bolt right on to your 429or your current 460...

LWard runs a carbed motor in his new truck build I think.... and got away with fooling the transmission If I remember right... He also knows his chit.. Look for his "ultimite build" thread its good reading for anyone with one of these trucks......

 

If he can find a C6 and change the output shaft and install a 4X4 adapter that would work, he'll just have to shorten the front and lengthen the rear driveshafts. Of the later 460s, the F3TZ heads are the best, the 90 will have E7TZ heads.

Maybe his cat is partially plugged? I have seen that the first gen EFI 460s are pigs, my son and one of his friends decided to see whose dually was faster. Mine is an 86, carbed, C6 and 3:55 gears, his was an 89, EFI and 4:10 gears. He walked away from the 89 in an impromtu drag race. If you can picture two crew cab duallies squaring off at a light (it was the middle of the night) it must have been a sight!

 

c9's and Doves came on stock cars..., id assume if he has a 450hp 429 its got c9's or Doves on it