If I asked the same question on some of the extreme snob sites I would be shot in the head immediately.

Can someone tell me what the basic differences are? I think I've heard of the 351 ci in both types. I don't get it. :confused:

Thanks in advance. ~Joshua

Wish I could give you a more detailed response, but I dont know too much about it either, but from what I know, they are just two different blocks and come in different displacements(at least I know the windsor does).

Cylinder heads is the biggest difference between the two motors hands down. The cleveland heads were designed with flow in mind WAY back in the day when Ford was Trans Am racing. The ports were WAY too big and the valves were over 2.100 I believe. Dont quote me, I need to do some research. The block itself sucks as the oiling is less then stellar. The intake as well is of course different too then a windsor.


As for a windsor, the oiling is definately better. The block can take over 650 from the factory but the heads and intake were highly restrictive. The new victor and victor glidden heads are extremely nice and getting easy 300++++cfm is not a problem

Our 395" windsor spins to 9600 rpm and we sit right at 870 hp on motor. Of course there is a lot more too it and we run a large bore / short stroke setup but it definately runs.

We are finally reaching a day and age with a valve train that can handle the clevelands HUGE heads and we can take advantage of that. In the late 60's when it came out was just not good at all. By the time the motor started making power, it went into valve float. Ford had the right concept, just only got half the puzzle right. 302 from GM in the Z28 is where it was at :D

Pretty much what he said.

Also, Cleaveland blocks have 2.75" main journals (which is commonly thought to allow for higher reving) where a Windsor block has 3" main journals (which is commonly thought to restrict high reving)

This theory isn't held by all, because there are alot of guys using Windsor blocks with great success.

Pretty much what he said.

Also, Cleaveland blocks have 2.75" main journals (which is commonly thought to allow for higher reving) where a Windsor block has 3" main journals (which is commonly thought to restrict high reving)

This theory isn't held by all, because there are alot of guys using Windsor blocks with great success.


Thanks for bringing that up, I completely forgot about that :o| Nice car by the way and welcome! :judge:

there ya go man! all summed up for ya

Cylinder heads is the biggest difference between the two motors hands down. The cleveland heads were designed with flow in mind WAY back in the day when Ford was Trans Am racing. The ports were WAY too big and the valves were over 2.100 I believe. Dont quote me, I need to do some research. The block itself sucks as the oiling is less then stellar. The intake as well is of course different too then a windsor.


As for a windsor, the oiling is definately better. The block can take over 650 from the factory but the heads and intake were highly restrictive. The new victor and victor glidden heads are extremely nice and getting easy 300++++cfm is not a problem

Our 395" windsor spins to 9600 rpm and we sit right at 870 hp on motor. Of course there is a lot more too it and we run a large bore / short stroke setup but it definately runs.

We are finally reaching a day and age with a valve train that can handle the clevelands HUGE heads and we can take advantage of that. In the late 60's when it came out was just not good at all. By the time the motor started making power, it went into valve float. Ford had the right concept, just only got half the puzzle right. 302 from GM in the Z28 is where it was at :D


9600RPM!!! Damn! And the Windsor blocks in the fox bodies certainly can't take 650hp from the factory from what I've seen/heard... Sooo, when I come down May 20-27th, you should show me what to do with my stock 89 motor... ;)

9600RPM!!! Damn! And the Windsor blocks in the fox bodies certainly can't take 650hp from the factory from what I've seen/heard... Sooo, when I come down May 20-27th, you should show me what to do with my stock 89 motor... ;)
arent the 351 and 302 blocks different? also, what is it that causes the block to break where it does?

arent the 351 and 302 blocks different? also, what is it that causes the block to break where it does?

The blocks are different. Not all 302 blocks are that weak either, mostly the common late model roller blocks. The Mexican and Boss 302 Blocks are much better but the 351 stuff doesnt have any really WEAK years like the 302 blocks. The 302 blocks split because there is nothing too them, especially in the mains. The blocks are fuggin LIGHT just picking them up compared to most blocks. They arent in the same league as a 351, LT1, Modular, LS1 ect ect.

69-74 351 Windsors are the strongest years for a factory 351W block. 69-71 blocks have a 9.48" deck height and 72-up have a 9.5" deck height.

All 351 cleavelands have a 9.2 deck height.

69-74 351 Windsors are the strongest years for a factory 351W block. 69-71 blocks have a 9.48" deck height and 72-up have a 9.5" deck height.

All 351 cleavelands have a 9.2 deck height.


The 302 mexican blocks are "known" to be better simply because they have a higher Nickel percentage in the cast then the other blocks. They were casted in Mexico and that is what happened when they made the metal for pouring.

It is better to get the earlier blocks for the "most" part simply because casting was not as refined as it is today. Back then they had to throw in a ton of metal and make the casting thick so the cylinders would stay straighter and have more rigidity. When the 302 came out in the early 80's ford completely changed America with their casting process and it enabled them to have thinner walls, less weight etc.

problem is everything else on that motor from the factory sucked performance wise. WIth it as a whole from the factory, it was very nice but the cylinder heads and intake were terrible. Definately do NOT flow well.

Also they take right at 500 hp before splitting a cylinder or straight down the lifter valley.

9600RPM!!! Damn! And the Windsor blocks in the fox bodies certainly can't take 650hp from the factory from what I've seen/heard... Sooo, when I come down May 20-27th, you should show me what to do with my stock 89 motor... ;)

Just let me know when you make it into Houston Kev. I can definatley let you come by the school and introduce you to a few of the guys. If you need any other help on your motor, just let me know and we can get you rolling for sure!

The 302 mexican blocks are "known" to be better simply because they have a higher Nickel percentage in the cast then the other blocks. They were casted in Mexico and that is what happened when they made the metal for pouring.

It is better to get the earlier blocks for the "most" part simply because casting was not as refined as it is today. Back then they had to throw in a ton of metal and make the casting thick so the cylinders would stay straighter and have more rigidity. When the 302 came out in the early 80's ford completely changed America with their casting process and it enabled them to have thinner walls, less weight etc.

problem is everything else on that motor from the factory sucked performance wise. WIth it as a whole from the factory, it was very nice but the cylinder heads and intake were terrible. Definately do NOT flow well.

Also they take right at 500 hp before splitting a cylinder or straight down the lifter valley.

Oh yea, mexican blocks are definately a stronger choice for a 302 block, the only bad thing is they aren't quite as easy to get ahold of as a standard 302. Good info there! Also mexican blocks have "Hecho en Mexico" casted into the lifter valley.

Back to the 351W blocks, a little known fact is that there were some 351W blocks made in mexico as well. They have weird casting numbers and also have "Hecho en Mexico" casted itno the lifter valley.