Max spring pressure on early SBFs before pressed studs tend to pull out?

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PackardV8
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by PackardV8 »

factory 1.6 rail rockers, 250* duration @ .050" . . . 135# seat around 300# open. . . . I didn't pin shit, I didn't weld shit, & I didn't convert to screw in studs. But maybe I'm just a lucky mf??
For true, turdwilly, you are just a lucky mofo. The pulled studs and broken factory rail rockers I've seen, with much less cam/spring and abuse than yours, would fill a five-gallon bucket.
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by NXBOY »

Ok, he has the stud boss mill end , but what type of tap do you guys recommend for 7/16 and power tapping?? I know he has to chamfer hole too, that is done last I suppose. I believe best not to get tap too tight so it can slip if binds, What do you guys use as cutting fluid? Thanks
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by pdq67 »

BirdMan wrote: Thu Feb 01, 2018 4:28 pm If you have the longer valves that come in 351W heads or I used .100 long Chevy valves (close to same length) then pull the studs, bolt the heads together opposite directions then they sit level on drill press. Insert the 7/16-nc tap in the drill press or mill after bolting heads down and tap all stud holes Without milling. You do not need to mill the stud bosses. The rockers will come close to stud nut but even using the large radius ones I didn't have a problem with Crane Gold rockers. Maybe some cheaper / bulkier ones would rub???
You mean deck to deck, bolted together here with intake ports on the same side?

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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by pamotorman »

you don't need to mill the stud bosses if you use this type of stud
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by turdwilly »

PackardV8 wrote: Thu Feb 01, 2018 6:02 pm
factory 1.6 rail rockers, 250* duration @ .050" . . . 135# seat around 300# open. . . . I didn't pin shit, I didn't weld shit, & I didn't convert to screw in studs. But maybe I'm just a lucky mf??
For true, turdwilly, you are just a lucky mofo. The pulled studs and broken factory rail rockers I've seen, with much less cam/spring and abuse than yours, would fill a five-gallon bucket.
I guess someone above was looking out for me then knowing that if something broke I would have been walking to work! Like I said...young & stupid. :roll:
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Post by dwilliams »

pamotorman wrote: Fri Feb 02, 2018 8:46 amyou don't need to mill the stud bosses if you use this type of stud
They work perfectly fine. Just make sure the vendor doesn't send you some New-Old-Stock Pontiac studs, or you'll have a real head-scratcher of a water leak...

I bought some studs from a local fastener shop once so I could get an engine done, rather than waiting a week or two for some to arrive by mail. Sixteen all alike, except for three that weren't. How those Pontiac studs got mixed in with the others was a mystery.
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by turbo2256b »

be carefull drilling and tapping you dont go through into the water jacket its a pain to seal them up and not leak down the road.
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by pamotorman »

i installed mine with epoxy in case the end user wanted to use the stock chevy adjustment nuts so they would not turn with the nut when backing off the adjustment.
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by NXBOY »

I ordered some like the pic. They won't pull out and if I break one atleast I can weld to it and remove worst case scenario. Just have to figure out if I have to drill deeper and how far is safe :roll: , Thnaks
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by pamotorman »

if you are going to tap the threads by hand you need a fixture to align the tap so it goes in straight. they are sold for SBC but you may have to machine your own for a ford. https://www.speedwaymotors.com/S-B-Chev ... 5kQAvD_BwE
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by NXBOY »

There Threaded, on the last head they where Alot tighter!
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Re: Max spring pressure on early SBFs before pressed studs tend to pull out?

Post by BirdMan »

You mean deck to deck, bolted together here with intake ports on the same side? pdq67 [/quote]

NO of course not opposite so that the valve cover side sits flat/level to be able to use drill press while resting flat on the table. Back in no race money days.

I have my first 351W heads machined like was said and I had to use two .100 thick hardened washers to get stud up high enough to use more than two threads for jam nuts. The first valves I used were the Ford Motorsports ones from their 1970 catalog. Later I used .100 long 5/16 Chevy valves which were very close to the original 351W long tip/rail rocker arm ones that they came with.
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