Pulling my 78 351m engine out this weekend
09-09-2013, 11:55 PM
#1
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Pulling my 78 351m engine out this weekend
I plan to pull my engine out this weekend, the rear main seal seems to be leaking, lost about a quart of oil driving a mile down the road. So while I have the engine out is there anything else you guys suggest I do?
09-13-2013, 08:34 AM
#2
I'd address anything else that would be difficult to with the engine still in the vehicle. I'd at the very least check the compression and make sure it's good because it's much easier to pull the heads and rotating assembly to clean up the bores and rering the pistons when the engine is out of the truck vs. in the truck. Ditto with listening very carefully for noises like a rod knock or noisy lifters. I'd also at the very least give the engine a good wash and a repaint.
The other thing I am sure will be suggested to do by others when you take your 351M out is to put a healthy 460 in its place. It's a drop-in replacement as they use the same bellhousing pattern and a 460 will be much stouter than any M-block in a similar state of tune. Personally, I'd turn the 351M into a 400M using the 400M's crank, rods, and get yourself some higher compression 400M pistons. (The 351M and 400M use the same block.) I'd also put on a good 4bbl intake and carb, cam (and check the timing) headers, and exhaust. The M blocks were very doggy from the factory due to emissions issues and what I described above will un-dog it quite nicely.
The other thing I am sure will be suggested to do by others when you take your 351M out is to put a healthy 460 in its place. It's a drop-in replacement as they use the same bellhousing pattern and a 460 will be much stouter than any M-block in a similar state of tune. Personally, I'd turn the 351M into a 400M using the 400M's crank, rods, and get yourself some higher compression 400M pistons. (The 351M and 400M use the same block.) I'd also put on a good 4bbl intake and carb, cam (and check the timing) headers, and exhaust. The M blocks were very doggy from the factory due to emissions issues and what I described above will un-dog it quite nicely.
09-13-2013, 12:25 PM
#3
vertical pin buster
Just beef up the 351. Flat top pistons rv cam and a intake and r bbl carb. With mechanical secondary. And headers I built one like that and it ran well in a f150 with a c6 with a manual shift body kit. I even placed a few times in half to. Truck phlls.
09-14-2013, 07:49 AM
#4
I'd prefer a vacuum secondary over a mechanical secondary on anything that is very heavy or doesn't have very deep gears in the rear. A mechanical secondary needs a vehicle where the engine can rev up very quickly after that throttle is pressed and the shots of fuel are dumped in, else it will bog. A dentside F-150 with 4.11s and a nonlockup transmission like the C6 might be able to get away with it, but only when it's empty. I've seen a few guys try to pull a trailer with mechanical secondary carbs and it is not pretty.
