I have a post that should generate some interest... I have a 66 Fastback that I have had about 15 years. Not long after I got it I ended up with a 289 from another car, rebuilt it and have had it in the car most of the 15 years I have had the car. Recently though, I decided to rebuild the "original" engine, the previous owner told me it was the original engine. Well, silly trusting me, I never really looked at it much - I put it on an engine stand and put a couple of bags over it... I disassembled it and had a local, reputable Mustang shop machine the block and crank, and order me up a 289 rebuild kit. My buddy (yikes, a vette guy - he helps me with my 'Stang, I help him with his 'Vettes, it's all good!) put his 'Vette engine into a performance shop and the guy told me that he would assemble my short block, very cheaply, and guarantee it for a year. Soooooo, I took him a truckload of stuff. That is where this whole thing gets interesting....
The performance guy called me and said things weren't fitting together. It appears from the casting on the block, C90E-60150, 9016, 15, that I have a 351 Windsor block, not a 289....Obviously not the original for the car. The Mustang shop obviously did NOT give me my crank back, it simply did not match up to that block, we believe it is for a 289. We think we have 351 piston rods, but we don't know how to tell. I have a book but it really doesn't go into too much detail about the differences between these 2 engines. I called the Mustang shop and spoke to the owner, i think there were some rear ends chewed because he wasn't happy they didn't pick up on it, because they did order me up a complete 289 rebuild kit, not a 351 kit. He did offer to trade me the 351 block for a 289, but my trust level with them is not what is should be either. The performance guy is suggesting that he just get a 351 crank, and assemble the engine. So, here is the real reason for this post.... What are the differences? From what I read the cam and carb I have (Edelbrock Performer-Plus #2122 cam and Edelbrock 600cfm #1406) should be fine. However, the nice Edelbrock Performer 289 aluminum intake manifold will not. What about the piston sizes? It appears the bores are all 4' but the Mustang shop pressed the new pistons and rods together already.... Hopefully someone can give me some ideas on which would be better, and possibly what to expect if I go forward with the 351w build...
Any help is greatly appreciated,
Dstanger

 

Cant help you with your question, but I know I would keep the 351W.

 

the rods/pistons will not fit. the 351w stock rod length is 5.956", and the length of the 289 is 5.155" (pretty sure).

 

Thanks so far for the posts. I'm thinking that the Mustang shop is willing to trade me a 289 block all machined and ready to go, I'll just do it that way. I see too many things that will cost $$$, really that I've already spent. I would still like to see any thoughts/comments that anyone has, I'm still trying to figure out what to do.

 

That really depends on what you want after you finish. A stock 351 W can be built to incredible HP as well as a stock 289. If it were mine, I would keep it 289.

 

that cam you have is gunna be a 289 firing order and a 351 crank has a different firing order then the 289. Those 2 wont jive, the carb is the only thing thats good so far.

 

This mystery deepens! This block has a casting of C90E-60150, which by all the books I have says it is a 351W. I took everything back to the Mustang shop that did all the machine work and I had every guy in the shop looking at this. This block, even though the casting indicates 351, is NOT! It has a car-id stamp on the top (I guess this was decreed law sometime around 1968) and it clearly shows a C car, or a 289-2V. The markings on the cam indicate 302 (W2), all of the piston rods are also 302 (C80E) and the Mustang shop says that I actually do have everything I need to build a 302. This is a very strange puzzle, wondered if anyone has any comments about a 289 block marked with C90E.... btw, we checked about every dimension and feature on this block, it is definitely a 289/302 block.....
Dstanger

 

Well the 289 and 302 had different strokes, so you could build a 302 instead. Piston swap should be all it needs.

Daver, I dont want to sound like a jerk, but FYI the 351 cams different firing order will work with any 302, 289,260,351 crank. They just have the combustion cycle on the other stroke for two pistons. When swapping firing order cams, you only need to change the plug wires on the cap. The crank wont care what cam is in it.

V8s only have two firing orders, doesnt matter if its GM, Chrysler, or Ford. Well as long as they are 180 degree engines. How they are numbered is what makes a difference. If you set up an early 302 or 289 with a GM firing order it will run if you use the same number sequence as the GM engine. Ford has #1 on the passenger side GM has it on the drivers side, in Fords #5 position. So if you bring #5 up on TDC and install the plug wire where the rotor is pointing, you will have number one for a GM. Confused yet?

If you want to know I can make a seperate thread or something, its just FYI anyway... kinda cool really..

 

Thumpin is absolutely right on the cylinder number stuff. Ford just elected to number theirs in a linear ( front to rear ) fashion where everyone else numbered theirs in a back and forth ( side to side ) fashion. TDC is TDC and the cam has no idea what firing order the manifold has stamped on it. JMHO, Dean

 

Even though the Windsor cam fires different, it is much better for your 289/302. Instead of firing 1-5-4-2-6-3-7-8, it will fire 1-3-7-2-6-5-4-8. The Windsor firing order is less stressful on your engine.