how much will a sbf take

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DaveMcLain
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Re: how much will a sbf take

Post by DaveMcLain » Sun Dec 17, 2017 2:15 pm

The real problem with the factory Ford small blocks is that they just don't have very good main webbing. Sure a lot of them are pretty thin on the cylinders but filling with Hard Blok can help a lot in that department. Main webbing not so much..

For what they were originally designed to do they do a fine job. If you would have told one of the original factory designers at Ford that you'd be pushing more than even 500 horsepower through the blocks I doubt they would believe its possible.

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Re: how much will a sbf take

Post by DaveMcLain » Sun Dec 17, 2017 2:15 pm

Casper393W wrote:
Sun Dec 17, 2017 12:03 pm
AMXstocker1 wrote:
Sun Dec 17, 2017 10:44 am
we run an amc and i'm asking because there is alot of 351 windsor based competition in the class we run and the class doesn't allow billet mains or hardblock so no poured blocks and its NA only and atleast a couple of these cars are capable of upper 9s in the 1/4 and 6.30s in the 1/8th at 3000-3100lbs so there already making 650ish i'd assume. i'm trying to gauge how much faster this platform can be pushed before the webbing starts going away i know there are several 408s and a 358 so that with the et i'd guess they would be spinning more that 7000 pretty easily.
The early Windsor blocks have thicker main webs and higher nickel content. At the level you are at I wouldn't worry too much. Good machine work is you friend here
It's my belief that if you have a good balance job, main stud girdle, and don't forget to have the block Sonic checked out for core shift...you should be fine.

We used to run a class here in NC like what you are describing. It was called Performance Street. Rules were 3150lbs 420ci max NA we had 5 cars running Stock Windsor blocks and our ET's ended up around 5.90's
There is no such thing as a "high nickel" block.

cab0154
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Re: how much will a sbf take

Post by cab0154 » Sun Dec 17, 2017 2:23 pm

the early block are better than the later blocks in the 8.2s. but with the 8.2s 500-550 is about the limit. more stroke causes more cap chatter on the little caps and will end up cracking the mains. IMO the best thing you can do with a stock 8.2 block is keep stock stroke, run a forged internal balance crank and keep the rpm limit to about 7k.

i disagree with many on the early being better vs late block when it comes to 9.5 stuff. i have several of each of the rollers as well as the early stuff and they are pretty much the same through the mains. hell, we did a clevor with a bunch of leftover junk using a 1980 windsor block, and no one wants those. we used an internal balanced 4" stroke eagle crank and studded the stock mains. straub did a cam for it. the thing probably had 500 low 6 second 1/8 mile passes on motor with a set of D1 4v closed chambers, at 3k lbs before it was torn down to check for wear. everything looked perfect. it was shifted between 7800-8k, and a couple of times close to 9k. it probably made 600-650hp. just a bunch of junk that ran way better than we thought it would.
Last edited by cab0154 on Sun Dec 17, 2017 2:34 pm, edited 4 times in total.

treyrags
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Re: how much will a sbf take

Post by treyrags » Sun Dec 17, 2017 2:31 pm

Casper393W wrote:
Sun Dec 17, 2017 12:03 pm
AMXstocker1 wrote:
Sun Dec 17, 2017 10:44 am
we run an amc and i'm asking because there is alot of 351 windsor based competition in the class we run and the class doesn't allow billet mains or hardblock so no poured blocks and its NA only and atleast a couple of these cars are capable of upper 9s in the 1/4 and 6.30s in the 1/8th at 3000-3100lbs so there already making 650ish i'd assume. i'm trying to gauge how much faster this platform can be pushed before the webbing starts going away i know there are several 408s and a 358 so that with the et i'd guess they would be spinning more that 7000 pretty easily.
The early Windsor blocks have thicker main webs
69 and 70

Steve.k
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Re: how much will a sbf take

Post by Steve.k » Sun Dec 17, 2017 2:55 pm

I remember us talking about this numerous times on network54. A long time cleveland racer said they were pushing the envelope of the c so they decided to jump on the clevor band wagon. After a run of Windsor blocks they basically concluded no gains once so ever in strength. The only real benifit in later years was the availability of new blocks as compared to junkyard or used Cleveland blocks.I also chatted with a florida area pro stock cleveland racer about block strength. He said they never had many issues with blocks back then as they could buy new from Ford. There biggest issue was valves he told me. Until trw came out with titanium valves nothing held together at the rpm they spun.

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Re: how much will a sbf take

Post by turbo2256b » Sun Dec 17, 2017 4:14 pm

qUITE A WHILE BACK a guy set picks of a 69 351W block and a 74 and no question about the difference of meat in the main web area.

Chevy 350 heads were the bigest advantage to ford running as cast head classes. If Ford engines were allowed to run 2V 351C not 4V things would be a lot more even as they flow about the same as the Chevy heads.

Ran my 69 351W up in the 8500 range for around 30K before building the C motor mentioned earlier in the same car.

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Re: how much will a sbf take

Post by DaveMcLain » Sun Dec 17, 2017 5:34 pm

turbo2256b wrote:
Sun Dec 17, 2017 4:14 pm
qUITE A WHILE BACK a guy set picks of a 69 351W block and a 74 and no question about the difference of meat in the main web area.

Chevy 350 heads were the bigest advantage to ford running as cast head classes. If Ford engines were allowed to run 2V 351C not 4V things would be a lot more even as they flow about the same as the Chevy heads.

Ran my 69 351W up in the 8500 range for around 30K before building the C motor mentioned earlier in the same car.
Best solution is to run the 4V head on a shortblock with more displacement. Especially in an as cast situation the Chevy head wouldn't have a chance. I think that the earlier 351 Windsor main webbing looks more like the 351C with an unused provision for a 4 bolt cap. I think that the Cleveland while still weak in that area is probably superior to the Windsor because of the wider main caps.

I built a 408 Cleveland with CHI heads for the Engine Masters' about 13 years ago and as far as I know that engine is still alive and well in a Cobra replica. It made 658 horsepower on 91 octane at Bill Mitchell's.

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