OK, the Cleveland was released in '70. That means the Boss 302 was still made and released for a full year before the Cleveland. The Cleveland heads were still a redesign of the Boss heads. The 429 was introduced in 1968 wasn't it? The Boss 302 was a design based on the 429 - the both have the cross-over water ports in the head and intake. They pretty much share the same port to cu." ratio or are the ports on the 429 smaller relative to size of the engine? This whole big port/valve is a reaction to the extremely small ports on the "Y" block 272, 292, 312 engines. Ford engines couldn't ever breathe enough and the Ford started making engines with too much breathing capacity. It all ended with the Boss and four barrel Cleveland heads. The Four barrel Cleveland intake ports were so big that in order to get better than 75% volumetric efficiency the engine had to be turning 8000 rpm. What I wonder is when is Ford going to let the exhaust size catch up to the intake? When are we going to see an engine that has good breathing on the exhause side? it would be nice to have good cams that didn't have to have split curves to make an engine run well. The cam grinders have to be tired of making a cam with two lobe profiles one it. One duration for the intake and add ten degrees to the exhaust duration so they will breathe properly. Of course it is a moot point now because our favorite small blocks are no longer being made. (except in the performance and after market areas)
The aftermarket and head porters took care of the exhaust difficiencies. And the 335/385 head designs hardly had any start in the Y block heads. The FE head designs were the improvement in that instance. The FE's strangely had no exhaust flow restrictions. And nobody claims you were off in the "what came first" arguement. On the contrary, the 335 series was more than likely developed right alongside the Boss 302, just because it was released in the following model year means nothing. Ford's taking the Cleveland heads and making the Boss 302 was a response to the high rpm failures with the Tunnel Port 302 of 68. The Peterson book is also incorrect in the statement that the Cleveland was killed in 73, in fact it lived on another 10 years "down under"
Back to the original question,with the abundance of aftermarket support for the "regular" 302s,I believe they are just as capable of big HP as the bosses.Also,the boss engines are very rare and the unique parts inside make them fairly expensive to "play with".The biggest holdback on the SBF has always been the heads,now there are several aftermarket heads available that allow them to breath quite well.And they are for the most part a direct bolt on(not requiring spacers or special intakes)
The original Boss 302 parts are rare, but it's entirely possible to build one that equals and exceeds it with new parts. The only O.E. part needed is the intake and these come up on ebay frequently and sell for about $400.
I have worked on countless Cleveland equipped 1970 Mustangs and Cougars. I own one. In my experience, Ford switched the 2 barrel version from Windsor to Cleveland mid year. I can look in my driveway for proof. Almost all 4 barrel versions in 1970 were Clevelands. Ford literature from the time supports this.
I agree that the 302 can be a strong motor. It is capable of 1 1/2 hp per cu" in the proper hands while living a long productive life. It is by no means capable of making the same hp as the Boss engine. The strength of the Boss block allows it to turn higher rpms and hold more combustion pressure than its weaker cousin. I have never seen a Boss block broken in half which is all too common with high hp 302s. That, I believe, is why they have introduced a "new" Boss block. The 302 may be out of the production cars but it is still very active in the rodding industry. There is still enough demand for the small block to warrant the (re)production of a stronger block. The 302 is limited too by its deck height. The original question was; "what is the difference . . . and which do you prefer?" I prefer the 302 of the two in question. Parts availability, cost and size are its advantages. I would expand the choice to include the 351W because I like it better than the 302 because it has the cu." capacity that provides for more hp capacity at lower rpm
I thought the 351 cleveland motor were under developement and the trans am dudes needed a replacement for the tunnel port head of 68. Then took the 351c head and adapted it to the 302 thus the boss was born. All the books I have say it was that way not the boss head was adapted to the 351c As for the question save money and build a nice 302. The street boss I have made has cost a ton of money......it's in the $6000-$6500 for just a 306!!!!!
I guess we've got an expert here that worked at Ford when all this was going on. (funny how you keep claiming the Boss was first over the Cleveland cause it was in production a year sooner, but the fact that the 429 came out in 68 doesn't matter)
This is from the Boss 302 registery.......maybe you better contact them so they get there facts straight Paul http://www.boss302.com/story.htm
It is a personal LYCOS web page - It has nothing to do with FOMOCO. Get the information from the Ford site and then you can be the expert. Just because its on the internet doesn't mean that it is of any value.
So what are your facts countering the Boss 302 Registery and Dr John Craft the author of Boss & Cobra Jet Mustangs.
Just to throw in my 2 cents here, but as far as I've always heard the 351C was first available in 1970. Lots of Mach 1 'Stangs and Torinos had them, I guess.
Paul, I have learned that you definately have your areas of expertise and have earned your place here on the board, but this topic is not your strong point. This will make the third time we have argued this exact point. I have said everything I need to say the first 2 times... http://mmb.maverick.to/showthread.php?t=19010&highlight=Tunnel+port+302 And... http://mmb.maverick.to/showthread.php?t=26251&highlight=Tunnel+port+302
