335 series 400ci in a 67

[xlman]

Oh ya, doin' the swap. This engine is a torque monster, no need for high rpm's. Got a C6 for it. Has "anyone" on this site done the 335 series (351C, 351M, 400) swap? Reason is, i have this engine (perfect shape) in my pickup and i'm rebuilding a 1969 460ci to put in it's place. So... the 400 is going into the Stang. If anyone here has done this, i'd appreciate your input! Thanks!

 

[rebel65]

i know dodgestang has put a 351c in his fastback, his is a 66 tho. might want to check out his site, dodgestang dot com

 

[rbohm]

putting a 400m into the 67 mustang is almost exactly like putting a 460 into the same car. the difference is that you will have to build your own headers as to my knowledge no one makes a header that will fit.

 

[htwheelz67]

yep, its like doing a 429/460 the exhaust is the biggest issue as I dont know anyone who makes headers for a 351m/400m in an early mustang, but John Kaase has proved that the 400m is the new king of HP in the small bock ford (even though its like a big block) power dept. The last engine masters he won with one, it had a wierd 98 LCA on the cam but made over 600 hp with a pretty tame cam and CHI heads, I was blown away at the power numbers but the combo he created worked together perfectly like no other engine I have seen. I have not seen a 408 similarly built make that power. Good luck.......I think this will become a more popular swap in years to come. The underated hp deprived 400m power is unlocked.

 

[D.Hearne]

The headers aren't the only thing that'll be an issue, the spark plugs will require lifting the engine to change, plus the motor mounts will have to be fabricated, the 400 has mounts unique unto itself.

 

[xlman]

Rebel 65, that Cleveland (same block\shorter deck) would've been much harder in a 66. 67's were made to accept big blocks and the 335 series aren't really as big. Thanks for the info!

rbohm and htwheelz67, i did alot of looking and see that headers will be an issue. Probly just put cast manifolds on (with a good exit position) and fabricate the pipes. And htwheelz67, i read the shootout article where John Kaase blew them away with his 400!!!! Amazing!

D.Hearne, i am a retired machinist\welder and i never accept "can't", only "how" (LOL). Spark plug issues were usually solved in the early days by making access plates in wheel wells or opening them up completely (my cars only see rain by accident). Motor mounts are easy. Thank you also (got your pm).

I believe in research first, scratch head second and tackle third -- so any leads to this swap will be greatly appreciated! Thanks again guys!

 

[dodgestang]

You won't need access plates for the plugs. Just a 90 degree swivel adapter on the back of your spark plug socket. I change the plugs in mine without moving the motor. It is easier to do with the valve covers off but I've done it with the valve covers on enough times.

 

[htwheelz67]

If you are a fabricator then I'm sure you can modify a set of 351c headers to fit, dont bottle up the power with manifolds.

 

[xlman]

Dodgestang, i went to your site, "nice job"! You had a much harder job with yours'. My 67 i hope is a touch easier.

htwheelz67, i have headers on it now in the pickup but, it's street cammed and running a 750 holley vac\sec. Only useful to a little over 5500rpm. (monster torque to there though). With 3.20 gears it will still be a handfull. (LOL)

Here's my pickup showing off! http://www.youtube.com/watch?v=hPe4bzleY1w

Don't sneeze at the 335's! Alot were thrown away.

 

[D.Hearne]

D.Hearne, i am a retired machinist\welder and i never accept "can't", only "how" (LOL). Spark plug issues were usually solved in the early days by making access plates in wheel wells or opening them up completely (my cars only see rain by accident). Motor mounts are easy. Thank you also (got your pm).

I'm not retired (yet) but having had 10 years experience with a big block 67 Stang (in the 80's) there comes a point where the hassle of tuneups and header fitment (and removal) are more trouble than it's worth. Good luck, you're going to need it. The 400's are good engines, but they're on the expensive side as far as building one right (the piston & open chambered head issues) where it'll run on anything less than 93 octane gas with a comp ratio compareable to what an FE series engine will tolerate. I did a full blown build on one, but ended up pulling it from the 77 F100 it was in. I replaced it with a stock 400, cammed with a Summit K5200 cam topped with the 2 bbl intake and a Holley 500 carb. That one was far more pleasant to drive than the full tilt motor. The 351C will fit in a 65-66 without mods, but best done with the towers cut back for plug access. I'd advise doing the same for the 400.

 

[xlman]

D., 351C is almost exactly the same as 351M\400 (slightly shorter deck height). Initally, it seems odd that a car designed to accept a big block would be harder to transplant than the 2 previous yrs. I have no plans on changing the 400's current configuration. Very streetable, very reliable. I believe a bit of research will point me at the right set of cast exhaust manifolds with a suitable dump. Watch my youtube clip in my previous reply and you'll see how it propels a 4500 lb pickup. No more mods needed. That is "the" engine i'm using. Our 67 is not intended for originality so, cutting, chopping, modding underneath ain't a problem. Thanks for your input D.

 

[D.Hearne]

D., 351C is almost exactly the same as 351M\400 (slightly shorter deck height). Initally, it seems odd that a car designed to accept a big block would be harder to transplant than the 2 previous yrs. I have no plans on changing the 400's current configuration. Very streetable, very reliable. I believe a bit of research will point me at the right set of cast exhaust manifolds with a suitable dump. Watch my youtube clip in my previous reply and you'll see how it propels a 4500 lb pickup. No more mods needed. That is "the" engine i'm using. Our 67 is not intended for originality so, cutting, chopping, modding underneath ain't a problem. Thanks for your input D.

The 351C is much narrower than a 400. There's a 1.1" deck height difference that adds up to about a 2" wider motor (and taller). The 351 fits just fine in a 67-70, afterall the 70's came with the 351C as an option, so there's no mods to be done with a small block 67-70 car.. They're just a little tight in a 65-66 cause the engine bay is narrower.

 

[htwheelz67]

dont forget the weight factor as well....it will be tight but doable, I cant see a 400m with CI ex manifolds out performing a similar built or milder 393/408.

 

[rbohm]

The 351C is much narrower than a 400. There's a 1.1" deck height difference that adds up to about a 2" wider motor (and taller). The 351 fits just fine in a 67-70, afterall the 70's came with the 351C as an option, so there's no mods to be done with a small block 67-70 car.. They're just a little tight in a 65-66 cause the engine bay is narrower.

dont forget the bellhousing bolt pattern on the 351m/400 is the same as the 429/460, except for the rare early 400 blocks that used the 351c bellhousing pattern. engine mounts are also different.

 

[htwheelz67]

frankly if it were me I wouldn't do that swap unless I had a 400m built for racing like John Kasse's and I was racing. I would drop in a 460 torque monster before I would do a 400m at least there are parts available for that swap. But you could be the first, theres a guy that put in a 2.3 turbo in his 65 and he had to do the must2 swap and cut out the shock towers to make it fit. If you really want the 400m thats what I would do.

 

[xlman]

Thanks everyone! Gettin' alot of useful input here! Maybe the 460 sittin in my garage might be the pick (little heavier but alot more potential). I'll be posting with pics when the transplant starts! Later guys!

 

[htwheelz67]

it would be easier as they make motor mounts, headers etc... for 429's in mustangs plus more intakes and cams are available.