400 CI in an 85 Stang

[LeeMoney]

Heres what ive got..
85 stang 2.3 L fully stock with manual T5OD
400 CI V8 out of 77 F-150

I plan on putting the engine in, but a few problems have come to my attention such as
1. Mustang rear end is 7.5 gear - ive read some articles that say this might break with a 400 CI
2. Tranny might not bolt up to the block right and the input shaft on the 2.3 is diff than for the 5.0 V8
3. Driveshaft might have to change since the 5.0 V8's had shorter shafts

Just wanted to know if anyone had some good info/advice

[Joe M]

Heres what ive got..
85 stang 2.3 L fully stock with manual T5OD
400 CI V8 out of 77 F-150

I plan on putting the engine in, but a few problems have come to my attention such as
1. Mustang rear end is 7.5 gear - ive read some articles that say this might break with a 400 CI
2. Tranny might not bolt up to the block right and the input shaft on the 2.3 is diff than for the 5.0 V8
3. Driveshaft might have to change since the 5.0 V8's had shorter shafts

Just wanted to know if anyone had some good info/advice

1) you will need an 8.8 rear end. Personally id just find a 9" and have it cut down. The t-5 stock is gonna fail sooner or later. They do on 302's and on the 400 its more likely. Id upgrade for a world class or talk to allstock93 and see what he wants to rebuild and upgrade yours. Its not gonna be cheap.
Driveshafts can be re done, but the 2.3 and 5.0 share similar driveshafts. but with the 400, i dont know if you can even use the stock t-5 + bellhousing, let alone know if you would want to.

[2 beer]

I am putting a 429 in mine this spring. If your gonna do it just go big block. I dont know shit about 400's though. I would recommend replacing the 7.5 though. I have one in my car right now and it will come out when the 429 goes in.

[Bill M]

Heres what ive got..
85 stang 2.3 L fully stock with manual T5OD
400 CI V8 out of 77 F-150

I plan on putting the engine in, but a few problems have come to my attention such as
1. Mustang rear end is 7.5 gear - ive read some articles that say this might break with a 400 CI
2. Tranny might not bolt up to the block right and the input shaft on the 2.3 is diff than for the 5.0 V8
3. Driveshaft might have to change since the 5.0 V8's had shorter shafts

Just wanted to know if anyone had some good info/advice

I would bet a '87 HO motor would make more power than a '77 400. The trans wont hold any power and the rear wont either. I 'd find another donor motor/trans/rear. The big block idea sounds great.

[gutlas5]

i'd put a 460 in it. they make motor mounts, c6 tranns to bolt up, and hooker headers ment for the swap. and they make bolt in 9 in housings thta can handle any power you throw at it

[LeeMoney]

Well thing is i already have my 400 and its pretty much ready to go.
The 400 is pretty much a 351 with longer strokes and i for sure want a manual in it. Im willing to throw some money at the tranny if its necessary, but would prefer a cheaper alternative. Im not going to be producing rediculous amounts of HP or anything (probably 200 to 250).

As for the rear end i have heard that tbirds have 8.8's and that just replacing the whole axle isnt much trouble. Anyone know anything about this or is it just a load of bs?

[LX Sport]

First, im pretty sure that T-5 is gonna break pretty fast. The T-5's in the 4 cylinders and 5.0s are different (atleast thats what ive been told). The 4 cylinders are weaker. Second, the 351/400M block is not a smallblock, so a 302/351W based bellhousing isnt gonna work, or atleast shouldnt bolt right up. your gonna want a 8.8, but with 200-250 rwhp, you might be alright with the 7.5

with that being said, i would really recommand NOT putting a 400 in your fox, the end result will not be worth it. if your gonna put a big ass heavy motor in your fox, do a 460. but if you want to do a motor swap, just get a decent 302 or 351W and do it. you'll be able to make more power for less money and less hassel.

[gutlas5]

you could put a small blcok chevy in it???? hehehehehe but a 400 making liek 200 hp? uhhh find a 5.0 form the same year, it'll make just as much power and weigh a lot less. and ou can either just bolt stuff togeher and replace shit as it breaks, or just gut the dirveline to sell before you break it and put in good stuff. almost everyone on here will recommend throwing in a 5.0 and tranny, and a 88 and call it done.seeing how there easier to find parts for. sae yourslef the hassle of tyrign to find 400 headers and a tranny. but hey, thats just my two cents.

[worduphomefry]

yeah i'd have to agree with that. what is the point of putting that in when it'll make about the same power of the 302 while being heavier and more of a hassle to do. like what was said before go 460 or just stick to the small block and go 351 from a truck. you can find those for cheap and you'll be able to make nice power and the 5.0 stuff will work with it.

is there a specific reason you're going with a 400?

[StangerJon]

because he already has the 400.


it was just fully rebuilt.

[theduckylittle]

Heres what ive got..
85 stang 2.3 L fully stock with manual T5OD
400 CI V8 out of 77 F-150

I plan on putting the engine in, but a few problems have come to my attention such as
1. Mustang rear end is 7.5 gear - ive read some articles that say this might break with a 400 CI
2. Tranny might not bolt up to the block right and the input shaft on the 2.3 is diff than for the 5.0 V8
3. Driveshaft might have to change since the 5.0 V8's had shorter shafts

Just wanted to know if anyone had some good info/advice

Okay, the 400CI is the 400"M" engine. Good News/Bad News. The "M" engines, when properly rebuilt, are tough as nails, and do have some potential because they are large bore engines with good flowing heads. You'll need a good cam to open it up the right way.

The Bad News: They use big block components to bolt up to things. You need to get 460 swap motor mounts and you'll need to get a transmission with the big-block bellhousing (this can be attained from the aftermarket for a reasonable cost, or from a junkyard C6 -- which is fairly common).

The oil-pan will need to be custom, becuase if I remember right the 351/400M doesn't match up with the 351C or 460 swap oil-pans.

Also, your T5/2.3 is pretty much useless for you at this point. (If you want to throw it out, I'll come pick it up, because I have no money... and need more donor blocks to cut up for some testing...) But the 2.3L bellhousing on the T5 is wrong for anything but the 2.3 and putting a 5.0 bellhousing on it won't do you any good because it doesn't fit the 400M either.

Good news: If you get a C4, and order up a 460-bellhousing for it your driveshaft and cross-memeber will bolt right up!

Don't buy into the "You should just shorten a Ford-9" rhetoric. Joe, I'm sorry meng, but you've never had to do this before, don't work with Fox-bodies, and the expense isn't worth the outcome. An 8.8" is PLENTY strong for a NUMBER of applications. Guys run 9's on an 8.8" and it will be SIGNIFICANTLY cheaper than ever putting a Ford-9" into a Fox-body.

Yet another thing to consider is the headers for the swap. The 400M is a W-I-D-E engine. You might be able to use some modified 351C swap headers to get the job done, but be prepared to run manual steering and get creative with a BFH in order to get everything to fit.

Due to the height of the 400, you may also need to get a cowl hood or be willing to "selectively modify" the hood that you have in order to get clearance for the carb and air-cleaner assembly.

-Duck

[theduckylittle]

your gonna want a 8.8, but with 200-250 rwhp, you might be alright with the 7.5

Yeah... so long as the power isn't that high and he's not doing 6,000 RPM drops at every light the 7.5" will be fine for a while...

-Duck

[theduckylittle]

http://www.mustangsandmore.com/ubb/Forum12/HTML/008979.html

Here's some useful information on 400M's... apparently a lot more stout than I thought.

-Duck

[Racin Repair]

The 400 is just as heavy as a 460, it is not worth the hassle to put in your car. A 400 can be made to obtain around 500 horse but the problems is you need to do some good porting work because the head castings are junk, the ports don't line up to the exhaust or intake very well. Good pistons are expensive for it, and they have alot of internal drag with the very large journals on the crank, they can last along time in low horspower aplications like they were meant to but they just aren't efficient motors. A rebuilt 400 is still a boat anchor, stick with a 302 or 351w and you'll save many many hours and be much happier. Now as far as putting a t-bird 8.8 in it, not gonna happen with out having it narrowed, the t-bird shares the same chassis as the Lincoln Mark and its wider and longer. I had a 7.5 with 3.08 gears live up to a to mild 351w with a top loader 4spd, they key is no traction!

If someone gives you a 351m-400m and its brand new- refuse it, don't put it in a fox, don't even do the big block in a fox they're too heavy and unless you have back halfed the car the weight distribution is going to be way off and you always have traction problems and you'll end up with a mustang that has big block that handles like crap and has problems getting out of its own way.

[theduckylittle]

Now as far as putting a t-bird 8.8 in it, not gonna happen with out having it narrowed, the t-bird shares the same chassis as the Lincoln Mark and its wider and longer.

That's not true. It's only 3/4" longer, and it doesn't need to be narrowed, you just need to swap in Mustang axels + bolt on mustang brakes. Both of which can be sourced from the 7.5". All the 7.5" rear-end hardware BOLTS ON to a 8.8".

My Capri has a Lincoln Mark VII rear-end in it right now... and guess where I got all the stopping hardware?

-Duck