I have a 1979 ford F250 crewcab with a 400m engine, with a holly 600cfm carburetor. I bought the truck sight unseen out of Colorado, something I will never do again. When I got it back to east Tn. I learned that it had water in the oil. The oil was a gray sludge and the shop that I had doing the body work had the heads machined and the gasket replaced. With some new 20w 50 oil in the old truck I an not getting any oil pressure after about 10 minutes of run time, in the short 15 mile drive home the lifters started to clack if I went over 50mph. Doing some reading I know that I am looking at some serious issues. I have no idea how long or how much driving was done on the engine with the head gasket leak. I would like your input on weather I should stick with engine and have it rebuild or replace it with a jasper engine. My goal for the truck is to make it my daily driver, about 12000 miles a year. I am not concerned with keeping a matching numbers or stock appearance I want to make it a reliable driver for the next 20 years. I would also like to keep it close to $3,000 for the engine since i tapped the bank for body and paint. I unfortunately will have to have someone do the work for me since my job does not allow me much free time and my lack of tools or knowledge or guidance from someone who knows what they are doing.

 

Since you're not able to do it yourself, go with a Jasper - 3yr/100,000 mile warranty is good peace of mind.

Note: Whoever you get the new block from, Have them send you the Block Casting number and foundry name (MCC, CF or DIF) so you can verify it's not a defective MCC Block. That's the ONLY issue with the 351M/400's to worry about.

 

With very few exceptions like K-Code Mustangs, there is really no such thing as a "Numbers Matching" Ford... That's a GM thing where they cast or stamped VINs on engine blocks.

The closest Fords get is being "period correct". Meaning, the part number or casting ID could have been installed based on a specific build date.. typically up to 60 days before the truck was bucked.

2x with Jasper based on your situation.

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I put a Jasper 400 in mine about 2 years/24,000 miles ago and have had zero problems. The thing runs like a top. It's my daily driver.

 

There is no F-ing way I would put a Jasper engine with it's OEM spec cam and gears into a truck that already has an aftermarket manifold and 600 cfm carb. Now, if Jasper would install a mild cam and full roller timing set straight up, then maybe.

It would be interesting to know how much a local guy would charge to build one with a Summit SUM-5200 cam and timing set, and Tim's oil mods. The parts are barely more $ than OEM and make a world of difference.

One of my wife's brother-in-laws used to own an engine rebuilding place, and unless you got pretty radical, the price difference between totally OEM and "what the manufacturer should have done to begin with" is small. The machining still costs the same.