351 Engine Question

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This info is in every corner of the internet...

1969-1974ish: Strongest blocks with the most material in the casting. Two piece rear main seal, oil dip stick in the timing cover, flat tappet cam. '69 (and maybe '70?) had a shorter deck height than all the other years.

75-up: Oil dip stick moved to side of the block, material was removed from the casting to make it lighter but also made it weaker.

84-up: One piece rear main seal.

94-up: Roller cam.

That's it in a nutshell. The years aren't perfect science, you need to physically inspect a block to make sure you know what you're getting. Any year Windsor will support 700ish HP; depending on tune and rpm it could be higher. Early (69-74) blocks are said to support even more.
 
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Used a 69 block for my 393w stroker and have the dip stick on the side in the pan.
Just used a Ford 351 swap pan and my original 302 timing cover.
If you want to run a roller cam in a non-roller block just use a set of link bar lifters.
 
Used a 69 block for my 393w stroker and have the dip stick on the side in the pan.
Just used a Ford 351 swap pan and my original 302 timing cover.
If you want to run a roller cam in a non-roller block just use a set of link bar lifters.
So I can not put a roller cam in a nonroller motor? You can't use the 351 oil pan or a 302 oil pan to fit in a fox body? Is there a benefit to having a roller motor over a nonroller?
 
So I can not put a roller cam in a nonroller motor? You can't use the 351 oil pan or a 302 oil pan to fit in a fox body? Is there a benefit to having a roller motor over a nonroller?
No, you need to either use link bar lifters or have the block machined to accept the hold down bolts for the spider tray in order to run a roller in non-roller block. Easier imo to just use a set of link bar lifters.
You need to use a pan with the correct bolt pattern/size for the 351 and has to fit the fox K member.
I'm sure Canton or someone like that makes one I used the Ford swap pan, not sure of any factory pans that would work

With a roller cam your able to run steeper ramp rates, Foxbody 5.0s are roller cam 302s with spider tray and dog bones to hold lifters.
You could always run non-roller cam if you want, not sure what your building.
 
Roller cam allows for more advanced lobe design, meaning you get more performance workout sacrificing drivability. Even better though, is roller requires zero break in and effectively last forever assuming the engine gets regular oil changes.

Oh and, if memory serves, the old 351 Crown Vic oil pan works for Fox swaps, but those are probably getting rare and you want a new pick up tube anyway.
 
Trying to think here. Pretty sure the 94' and up blocks weren't actually roller lifter, but the block was pre-drilled for the roller lifter spider. Did a cam swap on a Lightning many years ago......I was pretty drunk at the time (this was in college, don't judge me). I remember the spider screwing right in. Anyway, I would go for the newest 351 block you can find. Better yet, just get a 4 bolt block and be done with it. It really isn't much money in the long run.

Kurt
 
351 Windsor blocks that start with F4 casting indicates roller block. The lifter valley area is thicker on these blocks, to accommodate the taller/longer roller lifters.
 
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Trying to think here. Pretty sure the 94' and up blocks weren't actually roller lifter, but the block was pre-drilled for the roller lifter spider. Did a cam swap on a Lightning many years ago......I was pretty drunk at the time (this was in college, don't judge me). I remember the spider screwing right in. Anyway, I would go for the newest 351 block you can find. Better yet, just get a 4 bolt block and be done with it. It really isn't much money in the long run.

Kurt
You're right. The early lightnings were flat tappet, even though the blocks were set up for roller. @srtthis knows the lightnings pretty well... Is this info correct?
 
You're right. The early lightnings were flat tappet, even though the blocks were set up for roller. @srtthis knows the lightnings pretty well... Is this info correct?


I have two of the F4 blocks, one from a 94 Lightning, the other from an F150. The Lightning motor has a flat tappet camshaft, the F150 motor has a roller camshaft. The blocks are the same, why Ford didn't use a roller cam in the Lightning is a mystery to me. I also found some interesting information about the 351W roller blocks while cruising a forum a couple of years ago. I don't remember the company, but they sold Ford stroker kits. One of the options they offered was a short block setup using seasoned F4 blocks. In a discussion about strokers, someone from this company said they had found many of these blocks developed cracks around the area where the cam bearings are. Said you couldn't see them in many cases, unless the cam bearings are removed. Just thought I'd share.
 
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Just read the whole thread. Its wild no one has reported an engine failure with the cracks at #2 and #4 camshaft bearings. I'd still rather have a non- cracked block....or less chance of it cracking in the future.
 
Yea, if you get a roller block you should inspect the spider boss area for cracks before you do anything with it. The one I yanked from the junk yard had no cracks.

My speculation is that it's probably something that happened during the casting or Ford's machining process, and if your block doesn't have it, you don't have anything to worry about.
 
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I'm with steel1 on the early blocks. However the next one I build will be based on the roller block due to availability, along with failure rate. I don't think there is quite enough metal thickness in the valley to drill and tap an old block for the spider.