Can anybody help me with my size and the year of my engine? I just got my 1969 mustang mach 1 home. And I'm looking for the year on my block? I ran the buck tag on it. Well it should have a 351w with a 4v carb in it, but it has a 2v engine in it. I don't know it is a 302 or a 351. I know that it is not a 351c because of the fuel pump bolts.
First off, very nice find! I like that car. It looks like it still has original paint.
A quick way to distinguish a 351W from a 302 is to look at the relationship between the distributor mounting surface and the front rail the intake seals against on the block. On a 351W that front rail is roughly 2" above the distributor mounting surface. On a 302 that distance is very small, 1/2" or so. The 351W is a much taller motor.
The 351W 2 barrel was the base motor in a 69 Mach 1 so it shouldn't be a 302. It could have ben changed somewhere in its life but that would have been a very poor choice of engine swaps. So, I hope that didn't occur.
Are you saying the engine code in the vin is an M for 4 barrel 351W or H for 2 barrel 351W? Without double checking, I believe it's the 5th character in the vin.
When it comes time for engine disassembly of an original 1969 351W, the 4 barrel version has flat top pistons with valve reliefs and the 2 barrel version has a dished piston for lower compression.
Like jeff421ford mentioned, casting numbers on the block will help. They are near the starter area.
Thanks for all the help. the car is a M code and I found the casting numbers under a LOT of oil. It is a 1975 351w 2v That came out of a Torino. This is no good for me to find parts to match up with the car.
And yes it as the factory paint on her. she is a barn find. she hasn't seen a road in 30+ years! I have mor pictures if you want to see it.
Welcome looks like you found the info you needed. Not to bad looking 69 Mach1. More pics after you get it cleaned up to see what you've got. Good luck JTS 71 Mach1
At least its a 351W. Bizarre that somebody didn't even put the 4 barrel setup back on it. There are pros and cons for a 75 351W. Pro, it has the slightly taller deck, 9.503" vs. 9.480 for 1969 and 1970. So off-the-shelf piston selections are much larger. Con, the 1975 cylinder heads are much less desirable because they have larger combustion chambers than the 1969 and 1970 resulting in lower compression ratios. Also, I've heard the 1969 block is a little stronger around the main web area.
Just do your homework during the rebuild and don't jump into it blindly. Most engine shops are not aware of the nuances in a 351W.
Still a great find!! Nice car!! My favorite Mustangs are the 1969 and 1970 Mach 1's and Boss 302's. It will be a fun project.
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