sick 351M
Freshman User
Joined: May 2002
Posts: 33
Likes: 0
From: Kalispell USA
sick 351M
Hi! I have a 1979 bronco with a sick 351M. is this a good engine? Should I rebuild it or is it better to go with something else? This rig is used for trailrunning/ camping....not a daily driver. Would like some power and low end torque, just enough to have fun!! I have heard some negatives about this engine, would like some more opinions...thanks! :7
Tuned
Joined: Jun 2001
Posts: 266
Likes: 0
sick 351M
>Hi! I have a 1979 bronco with a sick 351M. is this a good
>engine? Should I rebuild it or is it better to go with
>something else? This rig is used for trailrunning/
>camping....not a daily driver. Would like some power and
>low end torque, just enough to have fun!! I have heard some
>negatives about this engine, would like some more
>opinions...thanks! :7
...let's just say it is design challenged! A 351M is a destroked 400, so in rebuilding it you could (and should) swap the crank and pistons to turn it into a 400. It may be nearly as cheap to just pick up a used 400 and rebuild that. Built properly, you will see a big difference in low-end torque (even stock you would notice the difference). Take the CR up to 9.5:1, use a straight up cam sprocket, a mild cam, Performer intake, a 600 or 750 CFM carb, headers, dual exhaust, etc. A popular mod lately is to put Aussie heads on it. This will yield higher (10+) compression with the stock pistons, without detonation. Larger valves would be good too.
The 351M is a good motor, that has been hobbled by de-stroking. But as noted above, it can be fixed...
>engine? Should I rebuild it or is it better to go with
>something else? This rig is used for trailrunning/
>camping....not a daily driver. Would like some power and
>low end torque, just enough to have fun!! I have heard some
>negatives about this engine, would like some more
>opinions...thanks! :7
...let's just say it is design challenged! A 351M is a destroked 400, so in rebuilding it you could (and should) swap the crank and pistons to turn it into a 400. It may be nearly as cheap to just pick up a used 400 and rebuild that. Built properly, you will see a big difference in low-end torque (even stock you would notice the difference). Take the CR up to 9.5:1, use a straight up cam sprocket, a mild cam, Performer intake, a 600 or 750 CFM carb, headers, dual exhaust, etc. A popular mod lately is to put Aussie heads on it. This will yield higher (10+) compression with the stock pistons, without detonation. Larger valves would be good too.
The 351M is a good motor, that has been hobbled by de-stroking. But as noted above, it can be fixed...
Senior User
Joined: Jan 2002
Posts: 107
Likes: 0
From: Dallas Ga
sick 351M
I am rebuilding a 351 in to a 400 now. I bought my crank and brarings for $183.00 and 9.0 to 1 pistons for $20.00 each. It is not that much to do this mod. If have the 351m crank ground that's $85.00 or trade it in for a reconditioned one $140.00, so the crank is not much differance. The pistons for a 351m is $130.00 so the $160.00 for the pistons is only $30.00. Here is a link to check out http://home.earthlink.net/~tcrocker/400.html
