which 351W?

[cobra_neill]

hey guys, im after swapping the poorly 4cyl on the foxbody for a 351. i have a whole bunch of parts ready for the swap, like brakes, k member, suspension etc. i kinda know what i will need.

i keep seeing 351W motors for sale on allsorts of forums and websites, some of them ranging from $500 to $10,000! is there that much difference between them?

i need a carbed 351W, but where do i start? are the blocks identical between the late 60's models to the 90's motors found in trucks? i will be changing the cam, headers, heads and inlet manifold anyway, so if i pick up a cheap running motor then have it stripped and rebuilt my own way, will i get the same performance as if i paid a fortune for an earlier block?

any help will be appreciated. Neill

 

[pokerpoison]

Normally the bell housings are not the same nor is the balancing of the motor. This seems to be the first of many diffences. Fuel pumps were manual in the 60s vs electronic in the 90s. 60s motors were not fuel injected and drive shaft lengths were different as well.

Since you say you swapped out the 4 banger... Did you beef up the suspension on the the front end for the additional weight. Also what aabout the rear end ? Did you swap it out for an 8.8 ? 60s motors will need some work done to bolt up the cross members.

There are more things that I do not remember. I will let other posters chime in.

 

[65x2]

hey guys, im after swapping the poorly 4cyl on the foxbody for a 351. i have a whole bunch of parts ready for the swap, like brakes, k member, suspension etc. i kinda know what i will need.

i keep seeing 351W motors for sale on allsorts of forums and websites, some of them ranging from $500 to $10,000! is there that much difference between them?

i need a carbed 351W, but where do i start? are the blocks identical between the late 60's models to the 90's motors found in trucks? i will be changing the cam, headers, heads and inlet manifold anyway, so if i pick up a cheap running motor then have it stripped and rebuilt my own way, will i get the same performance as if i paid a fortune for an earlier block?

any help will be appreciated. Neill

Are you running stock or aftermarket heads? Aftermarket heads are so cheap now a days and would definitely help with the additional weight. But if stock, I believe C9 and D0 heads would be your best for large valves and ports.

If you're changing the cam, take into consideration in 94 (F4TE blocks) were roller compatible, but this doesn't mean they came with roller cams. 96 was when they became standard usage.

As far as intakes, again, aluminum aftermarket is the way to go IMO.

Pre-75 blocks are more stout than the later blocks. I think its like 8-10 lbs difference in weight actually.

Hope this helps!

 

[wrksnfx]

Go with the 1969-1973 351W motors they are the strongest blocks ford made OR get the new man o war block from world products which can be over bored and stroked to 470 C.I.D.

Some tech info on the small block ford motor.
http://www.mustangcentral.net/tech/sbfblocks.html

This will help w/ the swap.
http://www.mustangcentral.net/tech/351.html

 

[Planter]

Go with the 1969-1973 351W motors they are the strongest blocks ford made OR get the new man o war block from world products which can be over bored and stroked to 470 C.I.D.

Some tech info on the small block ford motor.
SBF Engine Blocks

This will help w/ the swap.
Mustang Central.net 351w Swap Info.

this man speaks with wisdom.

the 80's and 90's 351W blocks are weak. find a 69 block it's the strongest of them all. but anything up to 73 or 74 will work too.

 

[KingBlack]

whats your goal?

 

[truebluedevil02]

this man speaks with wisdom.

the 80's and 90's 351W blocks are weak. find a 69 block it's the strongest of them all. but anything up to 73 or 74 will work too.

If by weak you mean will only reliably hold 600whp then yes. As said above 69-74 are the strongest blocks and have held 1000hp but ANY year 351W block will hold over 600whp if the internals are good and you dont over rev it.

My 351 was an 83', stroked to 408ci, aluminum heads, carbed, spun it to 6500rpm and made over 500hp and never had a single problem. If you can score a 69-74 block jump on it but there harder to find and most places charge more for them. Unless your shooting for 700+whp ANY year block will do just fine. Good luck

 

[cobra_neill]

thanks for the info and links there guys! appreciate it.

The goals are around 400hp on a carbed motor as this is a convertible and will be used mostly by the Mrs. I haven't swapped the motor out yet as I'm gathering as much information as I can before randomly buying parts.

so far from the info i have gathered... i know i will have to swap the rear axle for an 8.8, change the k member for a 5.0 k member, and an oil pan to clear it. i will need 351w swap headers along with the shocks and springs. i will be welding in a set of subframe connectors as well for help with strength. The 2.3 radiator will be stout enough for mild street use, fuel pump needs to be swapped out for a manual pump and pickup for the EFI to carb swap. oh, and brakes will need to be swapped. i think thats everything that i know, no doubt i will remember other bits later.

i don't understand this roller cam thing though. i know a bit about the modular cobra motors, but this is all new to me. :shrug:

 

[Eds01Lightning]

thanks for the info and links there guys! appreciate it.


i don't understand this roller cam thing though. i know a bit about the modular cobra motors, but this is all new to me. :shrug:

One thing I've heard is that when using the flat tappet vs a roller cam you have to make sure that the oil you use has a zinc additive, without which, abnormal wear on the cam lobes will occur fairly quickly and a rebuilt will likely be in order. Many of the popular oils no longer have a zinc additive.

Here is a little info on the Flat Tappet Cams vs. Roller Cams.


Flat Tappet Cams vs. Roller Cams - Lunati Power

 

[Stopsign32v]

Late model blocks will be roller blocks the earlier ones will need a special lifter for a roller cam. If you are going solid roller go with whatever. A late model block will handle 650+hp so you will be fine with any block.

 

[99BOSS]

My Saleen has a 351 Sportsman block in it. Its a 2 bolt main but has extra material in the bulkheads and thicker panrails. Its rated in the Ford Racing catalog to handle 700 hp at 7000 rpm. This is still available and you can find one used. It should be cheaper than the new Boss 351 casting or a new aftermarket block. This was a improvement over the old Lightning 351 blocks of the early 90s.