351c to 429 swap

[zx2guy]

i own a 73 cougar with a 351c (2v), and an fmx trans. and the 351 is goin to get torn down, baked, and rebuilt, same with the trans. i found a 429 4 bbl w/ a c6 trans for $500 out of a 72 something or other. can i swap them with ease or will it take some creative work and elbow grease?

if i end up liking the 429 better i might buy another car to put it into, but the cougar i want to keep as origonal as possible. ( everything is origonal)

[MrPbody]

The Mustang was available with 429 in that era. I would think the engine mounts and exhaust from Mustang would fit the Cougar. You'll need a larger radiator, and probably need to shorten the driveshaft to accomidate the C-6. The wiring harness is also probably different.

Save the 429 for the "next" car. Get a Fox body and put a hurt on the SBC crowd. When you decide to build the 429, dump the crank and rods, and use 460 stuff. No substitute for cubic inches EXCEPT... "Cubic MONEY"!

Jim

[zx2guy]

460... were those the ones that had problems or was it the 400? anyway i asked a fellow ford geek at work and he says they wont line up and ill need to fab up ones, i need a different cross member and other assorted goodies. so damn. i might just buy it to hold onto it... since i found a 351 c that is in partial rebuild... all the fun stuff (cleaning boring honing ect) is taken care of. he'll sell the block for 250 ... 500 for the whole shibang including domed pistons, and the rebuilt heads. lemme know what you think.

[MagicRat]

The 351C is an excellent engine, and can produce nearly as much power as a 429. If the 351C is set up right, you will produce all the power your trans and rear axle can handle.

The money saved on the swap can go for headwork, or intake/exhaust work on the 351 to more than make up for the power loss.

The 351C is lighter and makes for a slightly better handling car. Back in the early 1970's, plenty of people opted for the 351 over the 429 specifically for the better handling.

[MrPbody]

While I agree the Cleveland is a good engine for performance, it's hardly in the league of any big block. All the same modifications to each would net a proportionally larger power output from the larger engine, and probably at a lower RPM..

"Dome" pistons imply high compression. High compression is not "street friendly", as race gas is required. 9.5:1 is considered the practical limit for 93 octane and iron heads.

We've had the best success with street Clevelands using 2-bbl. heads (with large valves installed, minor port work) and a reasonable cam profile. The 4-bbl. heads flow well at higher revs, but make no power under 3,500. The 2-bbl. heads can support up to 7,000 RPM with a good flat-tappet solid cam. Modifications to the valve train will be in order (screw-in studs, guidelplates, etc.).

The 460 is a tough monster. GREAT engine. You're thinking of the 351M/400. It really isn't a bad engine. It got a bad "rap" due to all the emmission controls attached and malfunctioning. They run hot in stock form. Once the systems have been updated, the engine can be very strong, and quite efficient. One of our Ford guys has one in his '78 long-bed/extended cab 150. He reports 16 MPG and has passed 100K on the rebuild. That's a 400 with Comp DE cam, Edelbrock Performer, Hooker headers and stock ignition, along with a 650 Holley vacuum secondary carb. Pulls a load, too! He has another '78 with 351M in it. It too, makes good power and reasonable fuel consumption. Amazing what we can do applying modern technology to obsolete designs!

Jim

[zx2guy]

but will those swap... and if so how easily. the 429 ild have to change a decent amount... what about the 351 m isnt that a small block with cleveland heads? or something like that. im looking to bolt out bolt in. all the fun computer stuff can wait. (i mean wiring)

[MrPbody]

No. The Midland engines (351M/400) have the "big block" bellhousing pattern used on the Lima (429/460) engines. They (the "M"s) are a "tall deck" version of the Cleveland, having a MUCH wider intake manifold. They DO use Cleveland 2-bbl. heads (a variation of them, anyway).

Jim

[zx2guy]

so the cleveland has the "small block pattern" then? (my ford motor history is limit thus the questions.. bare with me ill get it) which means the trans that came with it are limited to the c4 and fmx right? (thats auto... i have not seen a stick 73 cougar... im sure they are out there but i havent seen one)

[kermet1313]

Hey guys, . I gots me a '79 bronco just finished rebuildin the body , rebuilt dana 60 rear and and 40 front 3.5 gears, Im deliberating on wich to drop in : The 351w (bagged out) That i got it with or a 429 /w c6 trans from an f350 that i got stashed in the garage. The bronco is gunna be used mainly for climbin and diggin. What sort of ideas you guys care to share? Peace