I am going to put a 351c in my 79 F150. Two questions.

A. When I move the frame perches back towards the firewall, are there holes there or do they have to be measured and drilled. I looked at the perches, and there were holes behind them. Im just not sure if Ford made a "universal" type perch frame mounting holes.

and

B. Will certain parts of a 351m work with the new motor, 351c. exc. (radiator, frame perches,)

I just wanted to clarify before spending money. This is my first project truck and I am in no hurry. So, ill take my time, and keep good progress photos. Thanks for any info. Brian

 

Why a 351C? There are better engines for a truck.

 

You will need to get the engine mounts and maybe the perches from a truck that had a 302 or 351W. You will need to get the exhaust system mated up and being that a 351C was never installed into a truck like yours then the exhaust manifolds from a 351M or a 400 that was in a truck may have to be used. There are different exhaust manifolds for a 4V 351C and a 2V 351C. Although a 351M and 400 exhaust manifold will work on a 2V 351C they will not work on a 4V 351C because the 4V ports are huge compared to the 2V ones of any 2V 351C, 351M or 400.

Which 351C do you have? I am not sure if the oil pan will be a problem, but you will need to check the clearance and oil plug access. I do know that the way the accessories attatch to the engine are different for a truck engine verses a car engine, so that may be a problem for achieving proper clearance.

I do agree that there are better truck engine choices than a 351C. Although I have seen a pretty impressive performance with a 351C in a truck with a lower gear ratio. My 72 Torino has a mildly built 351C with the original 2.73 gear and it isn't too shabby with a 2V carb. My truck has a 2.75 gear and I don't think that the .02 difference is enough to make a 351C perform too bad. Just don't expect it to pull a loaded trailer as nice as a truck with a 351W does. The reason is because 2V 351C heads will outflow any stock 351W head. The higher RPMs it takes to make use of the torque capabitlity of a 351C is way higher in the rpm band than most people will ever use a truck. Don't even think about using 4V 351C heads in a stock truck and especially using it like a truck hauling loads around or you will be quickly disappointed.

Now if gas mileage isn't a problem then replace the rear gear ratio to a lower gear ratio so that at highway speeds you are revving the 351C to say around 2500-3000 and you will be in the ballpark and can enjoy the maximum hp and torque of a 351C in a truck. You will be even happier if you have a manual transmission because you can build a 351C even more than a stock automatic transmission will handle without using a stall torque convertor.

Here are a few more points about the 351C :
The main bearing journals are smaller in diameter than other engines like a 351W in order to reduce friction at higher rpms. The smaller journals are a weak link in using a 351C for a work truck engine. You can get a variation of compression ratios depending on which heads and aftermarket pistons you use. There are 2V 351Cs, 4V 351Cs, 351 Boss and 351 Cobra Jets. I think that is all of the versions of the 351 Cleveland, but I may have missed one.

I have an extra 351C just waiting to be needed one day. I have toyed with the idea of using it in my 76 F100 someday.


I would like to know how this turns out and what kind of low end performance you get with it. The best way to see how it does compared to what you have now is to take it to a local dragstrip and make a few passes before swapping in a 351C. Then go back after and make a few runs and compare the times. Post the differences here.

Anyway keep us posted if you do go the 351C route.