can somebody tell me if there is any such thing as a 400 Cleveland? Not just a 400 built at the Cleveland plant. I ran across a guy with a 70 Mustang and he claims it has a 400 Cleveland engine as advertised by Ford.

 

Hey oneslickhotrod, I think this guy is talking about a 400 modified. This motor is part of the 335 series. Basically you have the 351 cleveland and the 351/400modifieds.

Compared to the 351C block, the 400’s deck height is 10.297" vs. 9.206, the 400 has larger crankshaft main bearing journals, and the 400 uses longer connecting rods. The 400 gets its additional 49 cubic inches with a 4.00" stroke of the crankshaft (compared to the 3.50" stroke of the 351C).The 400 featured a 429/460 bell housing bolt pattern and the same bore diameter (4.00") and bore spacing (4.38") as the 351C and all later Windsor-class small blocks.

 

Hey tbolt, You took the words right out of my mouth except for the fact that 400m and 351m were geometry nightmares. You know , the 73 351's had the 385 series bellhousing too.

 

Ford really blew it on those M motors, good for a boat anchor, No power lousy fuel mileage, I think they had a chebbie engineer slip in on them, an pushed this idea....

 

In the early 70's, I think 1973, Ford retarded their cam timing to satisfy the EPA. That along with lower compression killed the horsepower ratings of their V-8's. If you put a new timing chain in one of the early 70's engines, make sure you have one that puts the cam straight up on TDC and it makes a world of difference in the stock engine. You can find Austrailian "Cleveland" 2v heads with "quench" combustion chambers and bring the old 8.6:1 engines up almost 2 points and really wake the old engines up. The Aussie's made 302 and 351 Clevelands up into the 1980's. From what I understand the Cleveland engine is as common there as a small block Chevy is here. The "M" heads do not flow well at all as the ports, especially the exhaust are really restricted due to the built in emission passageways in the head. These heads are all stamped "M" on the top corners beside the valve covers. These heads are very prone to crack and are not performance items at all. The American Cleveland heads will have a 2 or a 4 cast on top, referring to 2v or 4v port and valve size. The only quench chambers the US made were 4v's, as the Aussie's made them in 2v. The US did make a few 400's early on that had regular "Cleveland" 2v heads on them, but that would be a very rare find these days.

393c Stroker

 

[:@]it's montreal; not modified[sm=shootshoot.gif]

 

RamROd - you have the same senitiment as most on the 400. The 400 is one bad *** engine, that can easily be built to out run a 460 for less money. I recently built one for my 78 F250 that dynoed at 380hp and 490ft Lbs and it was less than $1800. The heads are an engineering marvel with the canted valves and lots of quench. The key to the 400 is compression - you need to get it up to 9.5 or 10:1 to make any real power from one. There are no pistons available, I was able to find some Nyland natural gas pistons that got the grunt we needed. The only other option is to use 4V Cleveland pistons and rework the pin end. Just some gristle to chew on.

 

400 Modified refers to the fact that the block design of the 400 was a modified version of the 351Cleveland. They started with a 351C did this, did that and ended with the 400 block design. I would agree engine valve timing and power were lacking. It was engineered as a "gas-sipper"- (Funny notion)Anyhow- the 351W took the cake from most of the smaller big blocks. Most people looking for big block action went all the way with the 460 and the smaller ones fell by the wayside as gramma's work horse cartin' groceries. Honestly if you put your mind to it you can make it work right (even though maybe the factory wasn't set on making it perform). I'll definitely agree with one thing though - man some of those Aussie motors were a sweet deal (I liked some of the body styles too).