I am in the process of upgrading my 1977 f-150 4x4's 351m motor with these parts that I am slowly aquiring (mostly by Ebay). Any suggestions or opinions would be great for I am not a mechanic and need all the help I can get. This is what I have piled up in the corner so far.: Edelbrock Performer 400 Intake, Edelbrock 600 cfm carb, MSD 6A ignition, Black Jack Headers, Airtex waterpump, Edelbrock pro-flo aircleaner, and the Edelbrock Valve covers. And Im about to order : Comp Cams 268h High Energy Cam kit, MSD distrubter and MSD Blaster Coil with the 8mm wires..

How is this so far???? Do I need things such as a oil pump, fuel pump, aux. oil cooler for this upgrade or anything else for that matter.. Im not sure about messing with the pistons or heads I think the stock set up is fine. The motor is smooth running as it is I just want more power and performance..

 

Don't forget a good aftermarket timing set that will allow you to remove the factory's built in 4 degree retard. Also consider investing in some springs for the distributor which will allow you to tune the mechanical advance.

 

Thanks for the tips, I added them to my notes...Luckily my uncle is a mechanic and he is going to help me install all the parts at his shop..

 

That's a great setup. The MSD distributor should come with not only a set of springs but also a set of cams that will positively stop the advance at whatever full advance you want. If you do any towing, try to grab an MSD adjustable timing control. I've got one and I can retard the timing down to about 6 degrees for towing and then advance it to 14 degrees for street performance. Also, you might want to consider going with electric fans. It's a cheap way to gain 15-30 hp and saves wear and tear on the water pump. I've got dual 14" PermaCools and they do a terrific job!!!

 

Im a fortunate to have found this site.....Im also pondering turning my 351m to 400. I know that the only diffence is the crankshaft and the pistons based on reading previous posts, But is it as simple as paying for crank kit (via PAW) and installing. I heard that there would be a deck height issue if this is done .And does it make much diffence between forged and cast pistons.. Also I have noticed that the compression ratio is also something to think about, I have read that there are pros and cons for going to a higher CR. I would like to stick with the stock heads for this project and I think that means sticking with a lower CR to prevent pinging.. I know I am rambling but one more thought, Is going .030 over something I need to do Ive seen it mentioned quite a bit..

 

Boring the cylinder walls is only required to clean them up for rebuild. You can go as low as .10 if that is all that is required. When changing to a 400, all that is needed is a 400 crank and pistons, I believe that the rods are the same? Clearance is not a problem as long as you don't mix and match cranks and pistons between 351m and 400. Hope this helps!

 

>Im a fortunate to have found this site.....Im also pondering
>turning my 351m to 400. I know that the only diffence is the
>crankshaft and the pistons based on reading previous posts,
>But is it as simple as paying for crank kit (via PAW) and
>installing. I heard that there would be a deck height issue
>if this is done .And does it make much diffence between
>forged and cast pistons.. Also I have noticed that the
>compression ratio is also something to think about, I have
>read that there are pros and cons for going to a higher CR.
>I would like to stick with the stock heads for this project
>and I think that means sticking with a lower CR to prevent
>pinging.. I know I am rambling but one more thought, Is
>going .030 over something I need to do Ive seen it mentioned
>quite a bit..

As long as you don't try to "mix n match" 351M and 400 cranks and pistons you're fine. Rods are the same. 400 pistons and a 400 crank are the only things you need to change a 351M into a 400.

Good luck finding "off the shelf" forged pistons for a 400 but you don't need them anyway. If you don't plan to race it or run nitrous or forced induction then you should be fine. Factory engines go hundreds of thousands of miles on cast pistons.

.030 is sort of a "standard" overbore in the industry. The overbore is needed when rebuilding higher mileage engines because the wear and tear of the combustion process tends to make the top of the cylinder larger than the bottom. Also since the pistons get sideloaded due to the rotation of the crank shaft it also tends to make the cylinders oval shaped instead of round.

When I had my 400 bored I told the machinist to take as little as possible and he was able to get away with .020. The flat top pistons I got come in that size so it was perfect.

 

 

I'd have to suggest that you go with some form of "HIGH VOLUME" oil pump when doing all these upgrades.... Im also doing the same rebuild right now and i have been told over and over that its inportant to have the higher volume of oil hitting the internal engine parts... JUST A SUGGESTION

 

If you go for a high volume pump then I'd suggest fitting a high volume sump as well. I'm not sure if it's such a huge problem with the 400's as they don't usually rev so high, but with the 351C the oil drain back can be restrictive and at high rpms the sump can be emptied with the result that the oil pump starts pumping air and hence bearings get destroyed.

 

Also, don't forget the extra oiler line from the front of the block next to the fuel pump back to a tee underneath the oil presure sending unit. It is a $40 insurance policy.