i'm buying a work truck......(not a mustang..but maybe ya'll can help)..it's a 76 or 78 f-250. it has a 400m..i'm wondering what are some cheap mods to grab some horse power?? exhaust,cam,heads,pistons..anything?? thanks
If it has high miles id rebuild it. I would do cam and intake aswell as carb, I think edelbrock sells a power package through summit thats pretty cheap. Some headers and good flowing mufflers will also help. I think Hedman sells longtubes for your application.
Well.. I would start by switching out those heads. Try finding some heads from 69-70 to help wake up your engine. I bought my complete DO0E heads for $80.00 plus shipping and they flow pretty well. Try Ebay for finding you an intake. Should be able to snag you one for $80-$150 depending upon which intake of course. You can get your cam from www.summitracing.com. Check out summit's grinds and you can pick one up for around $80.00 and thats including lifters. Although, I would encourage you to buy a better brand, but you said cheap.
The 400m is a stout brute, and will respond to the normal four barrel intake, cam and headers stuff. It is a fairly low compression motor. That can be improved with some head and block milling. Other than the low compression, the heads are decent as cast.
I bought 77 F150 with a 2 barrel 400m, with 157k miles and drove it 9 years to 205k miles. One of the best, most reliable vehicles I ever had. Towed boats and cars all over the place.
A 400M is a torque monster, I used to own a '78 F250 that had one; it lasted over 200,000 miles.
Those engines had some of the most restrictive intake and exhaust manifolds I have ever seen. Find yourself a nice 4bbl intake and carb, and a cheap set of headers. The stock cam is very mild, made for low end torque; you could grab some easy hp by swaping that for something w/ a little more duration. Look around on ebay, parts are easy to come by. Intake and exhaust parts are interchangeable for the 351M and the 400M, so keep that in mind when you're shopping around.
I'd think you'd be better off swapping it out for something a little easier and cheaper to build, but to each his own. Just not a real fan of the 400M boat anchors.
nahh...no swaping...i actually have a good running 302 i could put in...but nahhhh. i'll stay with the 400m. need somthing new to work on. anyways...i might be going towards the carb,intake,headers,and possibly a cam. thanks for ya'lls help.