SBF clarification please!

[nickpohlaandp]

Oh, I found this illustration too. I figured I'd post it up in case anyone else was having the same rod ratio/dwell time questions I had. It might help a little

Also on Google I found a post on ST from about 8 years ago talking about a very similar subject.

Sorry, posted this in the wrong thread

[12speedfurd]

Change in dipstick location isn't nearly as critical as the potential for one small block head fitting another. Of course you could make this mistake by trying to put some quality aftermarket heads on a 305 Chevy, but with Ford it seems you might be ok with the heads but later find out you're screwed on the bellhousing pattern. Too many variables

It's not as big of a deal as you think as long as you keep the Cleveland and Windsors separate. Ignore the modified motors. You will likely never see a 5 bolt 289 block, so basically all Windsors and Clevelands have the same bolt pattern.

You can put 302/289 heads on a Windsor by drilling the head bolt holes. 351w heads bolt to a 302 with a stepped washer.
All 289/302 front covers, oil covers and valve covers interchange. However you want the oil pan and timing cover to be matched because of dipstick location. Also, newer 302s have the dipstick in the block while older ones had them either on the pan or front cover.

[DaveMcLain]

So many variations with deck heights, bellhousing patterns, different blocks... makes my head hurt. There's no doubt that you can make good power with a Ford based mill, but I expect that the seemingly endless variations even within the same engine family are why so many people choose to build Chevy vs. Ford. There's more parts interchangeability and it's cheaper.

A Chevy V8 has plenty of weird unexplained changes too. For instance; the dip stick changes from the left side to the right side in about 1981, why?

Change in dipstick location isn't nearly as critical as the potential for one small block head fitting another. Of course you could make this mistake by trying to put some quality aftermarket heads on a 305 Chevy, but with Ford it seems you might be ok with the heads but later find out you're screwed on the bellhouding pattern. Too many variables

You never know.... How many people have screwed an old set of head to their Chevy only to find out that the heads don't have any bolt holes to mount the accessories.

[cjperformance]

Considering I know very little about Ford Blocks as well, maybe one of the Ford guys here could post the v-8 block sizes, like Bore, Deck Height, maybe Main Bore. That would sure be helpful.

ok. for Windsor class (8.2 and 9.5) and Cleveland/modified they are 4.38 bore centers.

for windsors: the 8.2 uses a 2.25" main, the 351w uses a 3"
8.2 deck: the 221 was 3.500x2.87, (the smogger 255 of the late 70s was 3.68x3.00), the 260 was 3.800x2.87, the 289 was 4.00x2.87 and the 302 was 4.0x3.0. up until about 64 during the 289s they were 5 bolt bellhousing blocks. then they started making the 289s and all the 302s were 6 bolt bellhousings.
9.48/9.5 deck 351w was 4.00x3.50.

the Cleveland was 4.00x3.50 also, with a 9.2 deck and 2.75" mains. the modifieds were kind of a hodgepodge which used 3" mains. the 351m I think was a 9.2 deck also, the 400m was a tall deck 351m, I think 10 or 10.2 deck height.

All modifieds, 351M/400, had 460 bell-housing bolt patterns and were the same deck dimension = 10.292" / 10.302"

There are early 400 blocks with 6 bolt small block pattern. The two that I had scrounged up (looking for an easy fit up to an existing sb case C6) soniced very thin about 1.5" down from the deck so I ended up just using a regular 400 block and did a BB case swap to the C6.

[falcongeorge]

Someone correct me if I am wrong, but I think the block deck heights were increased to lower compression from about 1972 to 1980 on the 302 and 351. Anyone know the details?

'76 for sure, could be a couple more years than that. I have a '76 block, I am on vacation right now so can't look it it up, but it's not a big difference. Just going by memory, I think it's about .040 taller?

[Daniel Jones]

One important change that I didn't see discussed was the balance factor change in 1981. Earlier SBF engines were 28.2 oz-in, as are all 351W and 351C/351M/400. Later 5.0L/302 cranks were lightened which required additional mass added to the harmonic balancer and flywheel/flexplate. 1981-up 5.0L/302 engines have a 50 oz-in balance factor.

Dan Jones

[Walter R. Malik]

The very first page

There are several small block Ford engines. They started with the 221 in 1962, then along cam the 260 and then the 289. All of those shared the 8.200 deck height as well as a 2.870 stroke. The displacement gains came only from bore size increases. Later in 1968 the 302 came along which used the same bore as a 289 but came with a 3 inch stroke. The pin height of the piston remained the same but the rod became shorter to accommodate the increase in stroke. Also on the old engines about mid '65 the bell housing pattern changed from one with five bolts to the familiar one with six bolts. All 221's and 260's are the 5 bolt but 289's can be either way, 302, 351Windsor, 351 Cleveland all use the same 6 bolt pattern.

In 1969 the 351 came along with an increase in stroke as well as deck height up to a nominal 9.500 from the 8.200 used previously. It is very similar to the 302 except for being a larger engine with a stronger block as well as a larger crankshaft featuring 3 inch main bearings. It also has 1/2 inch head bolts. In 1970 the 351 Cleveland was introduced and it uses a 9.200 deck height, 2.750 main bearing diameter along with a free flowing canted valve cylinder head which is similar to the head used on the Boss 302 in 1969. The Cleveland has a cast on timing cover that's sealed with a steel plate. The Cleveland was only produced from 1970 to about 1973. That design spawned the 400 in 1971 and the 351M a bit later which are also small block engines. The 400 and the 351M have a deck height that's again taller. 11.2 inches nominal right off the top of my head. When Ford developed the 400 they kept the 4 inch bore of the 351C, Windsor and 302 but went to a 4 inch stroke. The rods are also longer yet the piston compression height is the same as the 351C(pin is larger). The "M" block features the same bell housing as used on the 429/460 as well as a unique motor mount but it is still a small block engine.

All small block Ford production engines from 221 to 400 are externally balanced and they all use the 28oz hardware except for the 5.0 which uses the 50oz stuff. They start calling it a 5.0 around 1983 or so and that's when the balance factor changes yet the 351 Windsor never changes..

That should get you started...