Hey everyone, I have a 75 Maverick that blew a rod through the oil pan about 3 years ago. I had removed the 250cc engine with plans to rebuild the transmission and install a 5.0 that I picked up from a '92 F150. However, since revisiting the project, I am considering rebuilding the inline 6, as long as the block is not cracked. I would like to look at several options to weigh their feasibility. Here they are: 1. Rebuild the 250. I would appreciate any resources you may know of to help in this process. (If the block is cracked, I would most likely not rebuild it unless there are reman 250 short blocks out there to replace it.) 2. Buy a new crate engine. Again, any sites you know of that offers either the 250 or 302 would be great. 3. Install the 5.0. This is my least favorite option, since there will need to be quite a few modifications to both the engine (convert EFI back to carb, for one) and the engine bay. At this point, I am rebuilding the C4 transmission regardless of which route I take, since the 302 and 250 used the same bell housing. I appreciate any guidance you may provide!
Even if block isn't cracked, without serious machine work, I doubt the 250 is rebuildable. Anytime a engine tosses a rod, there were already serious issues. If lucky you may have five useable rods, but the crank is surely junk as likely are pistons. Eaiest fix by far is another 250 for replacement, if you look at a rebuilt engine, chances are you'll get zero $$ for your core. Granada & Monarch used to be good sources for 6 or 8 but those days are history. For a V8 swap, donor car is best, piecemeal it a PITA and costs probably 3-5X. The truck motor is a good choice but will need motor mounts, V8 flexplate, intake, carb, exhaust manifolds or headers, etc, etc, etc. Unless you find a pre'80 engine, will probably need all the pieces that the truck engine needs.
'Even if block isn't cracked, without serious machine work, I doubt the 250 is rebuildable.' true enuff, but don't get discouraged on getting your 75 running soon. the V8 conversion is do-able with enough parts and time but swapping in a viable six will be a lot simpler and faster if you don't require 'V8' posturing . The 250 in the '74 was 'Craigs List' low mileage - low cost motor from another Maverick V8 swap . After checking internals and adding a Supercharger, the anvil-strong 250 has run flawlessly for over 3 years with occasional boost levels approaching 1 bar. the 170 in the '63 is another Maverick motor from a low-mileage but total rotted '71 4dr on CL. It has a cyl. head from a donated blown 250 Mustang motor left out in weather after owner attempted a 351/C6 swap into the Mustang. The 351 swap was never completed and the Mustang never saw the road again but the 170 with 250 head still is rolling 15 years later. the '61 has a built 250 with Offy Tri-Power setup and does redline launches all day long. and a 200/C4 from a cheap CL parts' 76 Comet GT for another forced induction project. I also have two clean 250 block cores ready IF/When too much enthusiasm necessitates ... have fun
I do think the 250 is underappreciated as an engine. I really like having an inline 6 (every vehicle I've owned has had a straight 6) because I find the engine bay more spacious and easy to work in. I might just mess with the 250 I have just for fun, to get an idea of what taking apart an engine entails. After that, I'll take the 5.0 I already have and try to track down all the parts I'll need. If anyone has a list of parts for the 302 swap from 250, that'd save me a lot of time!
I would suggest finding a used 250-6 (they are out there from people doing the V-8 swap) and putting that in your car.
