Limits of sbf pedestal mount valvetrain?

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travis
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Limits of sbf pedestal mount valvetrain?

Post by travis » Sat Jun 23, 2018 12:47 pm

I’m gathering parts for my next 351w build. I’ve got a Jones 218/222@.050 hrol, .544/.544 lift with 1.6 rockers on order 8) and was on the hunt for some heads. I found a smoking deal on some AFR 165’s but they are pedestal mount, not stud mount rockers. Are pedestal mounts a concern at this point, or if I wanted to use a higher ratio rocker at some point? This is a street deal, probably 6200 absolute max rpm and more realistically spending most of its life under 5500. The 5/16” hold down bolts concern me a bit.

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Re: Limits of sbf pedestal mount valvetrain?

Post by Carnut1 » Sat Jun 23, 2018 3:26 pm

Screenshot_2018-06-23-15-20-39.png
If I understand your question this is the kit I had luck with. Studs are 5/16" that screw into the stock threads. The studs come with a decent foot on the stud and 3/8"-24 top threads. They worked with pretty snotty adjustable valve trains up to about 7000rpm hr cams. Thanks, Charlie
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Re: Limits of sbf pedestal mount valvetrain?

Post by Krooser » Sat Jun 23, 2018 4:47 pm

I ran pedestal rockers on a 289 oval track deal running 7k without a single problem.
Last place in the B-main is better than anyplace in the grandstands...

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Re: Limits of sbf pedestal mount valvetrain?

Post by bobalattie » Sat Jun 23, 2018 5:16 pm

I have run them with stamped stock rockers 6600 rpm with .500 lift aggressive hydraulic flat tappet in circle track application. 145/340 spring pressures.. I did upgrade to arp bolts..

I also had iron gt40 heads with scorpion rockers in my f150 with .544 lift hydraulic roller, not sure abt the spring pressures, these used the cap screws that came with the rockers and I never had a problem..

I have a set of the retrofit studs 5/16-3/8 collecting dust if you choose to go that direction..

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Re: Limits of sbf pedestal mount valvetrain?

Post by groberts101 » Sat Jun 23, 2018 7:27 pm

travis wrote:
Sat Jun 23, 2018 12:47 pm
I’m gathering parts for my next 351w build. I’ve got a Jones 218/222@.050 hrol, .544/.544 lift with 1.6 rockers on order 8) and was on the hunt for some heads. I found a smoking deal on some AFR 165’s but they are pedestal mount, not stud mount rockers. Are pedestal mounts a concern at this point, or if I wanted to use a higher ratio rocker at some point? This is a street deal, probably 6200 absolute max rpm and more realistically spending most of its life under 5500. The 5/16” hold down bolts concern me a bit.
Bread and butter type stuff for all the old 5.0 guys using bolt on upgrades. If you were just a bit wilder with lift and rpm I'd say go stud mount but those will work just fine for a milder 6,000 rpm street type deal.

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Re: Limits of sbf pedestal mount valvetrain?

Post by cgarb » Sat Jun 23, 2018 8:43 pm

If you don't have rockers yet, Harland Sharp makes a set that the rockers are paired together and are adjustable...a little mor expensive but would probably be piece of mind...plus you can adjust your preload as a bonus.

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Re: Limits of sbf pedestal mount valvetrain?

Post by travis » Sat Jun 23, 2018 9:29 pm

cgarb wrote:
Sat Jun 23, 2018 8:43 pm
If you don't have rockers yet, Harland Sharp makes a set that the rockers are paired together and are adjustable...a little mor expensive but would probably be piece of mind...plus you can adjust your preload as a bonus.
I was actually looking for some adjustable pedestal rockets and have come up with nothing yet. I vaguely remember some that had adjusters right above the pushrods that the PR seat cup was part of the adjuster, but the few places I’ve looked so far have nothing like that. I’ve never really liked adjustable pushrods but the only adjustable option I was finding from Summit is with what Charlie posted. I’ll keep looking

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Re: Limits of sbf pedestal mount valvetrain?

Post by Walter R. Malik » Sat Jun 23, 2018 9:35 pm

There are all sorts of pedestal / bolt down mountings available for a small block Ford engine ... some are really good and some are simply adequate for doing a lot less.

A bolt down system with a good bolt under tension can certainly be sturdier than a stud hanging out in the wind in single shear; even when the bolt diameter is a lot smaller.

It merely depends upon what kind of bolt down, pedestal system is being used.
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Re: Limits of sbf pedestal mount valvetrain?

Post by Walter R. Malik » Sat Jun 23, 2018 9:44 pm

travis wrote:
Sat Jun 23, 2018 9:29 pm
cgarb wrote:
Sat Jun 23, 2018 8:43 pm
If you don't have rockers yet, Harland Sharp makes a set that the rockers are paired together and are adjustable...a little mor expensive but would probably be piece of mind...plus you can adjust your preload as a bonus.
I was actually looking for some adjustable pedestal rockets and have come up with nothing yet. I vaguely remember some that had adjusters right above the pushrods that the PR seat cup was part of the adjuster, but the few places I’ve looked so far have nothing like that. I’ve never really liked adjustable pushrods but the only adjustable option I was finding from Summit is with what Charlie posted. I’ll keep looking
There a several rockers like that for a small block Ford Windsor, Cleveland or even a 429/460 big block.

A Harland Sharp 1.6/1 ratio set #S400076A is like that as well as a lot of others.
I use them all the time ... you have to call them and they will make them; 1.65/1 ratio also.
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Re: Limits of sbf pedestal mount valvetrain?

Post by Casper393W » Sat Jun 23, 2018 10:38 pm

For what you are doing you will be fine! I had a set of Scorpion Rockers and they we're Awesome! This setup was GT40X heads that I ran up to 6500 with no problems!

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Re: Limits of sbf pedestal mount valvetrain?

Post by MadBill » Sat Jun 23, 2018 11:14 pm

If you want to step it up a bit from the Crane upgrade kit, a 380" SBF road racer that I helped build (0.710"/0.670" Jones roller,~700 HP @ 7800 RPM) has had the same set of Yella Terra pedestal mount rockers in it for 5 seasons...
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Re: Limits of sbf pedestal mount valvetrain?

Post by travis » Sun Jun 24, 2018 12:00 am

After more investigation, it looks like there was 2 reasons why I couldn’t find them on Summits website. 1, the pictures they use are just generic stock photos most of the time and they are not pics of the adjustable ones, and 2, almost none of them actually say in the description whether they are adjustable or not #-o I eventually found plenty of choices after getting part numbers from each manufacturers websites.

MadBill, thanks, but somewhat overkill for the junk I throw together!

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Re: Limits of sbf pedestal mount valvetrain?

Post by Walter R. Malik » Sun Jun 24, 2018 11:31 am

MadBill wrote:
Sat Jun 23, 2018 11:14 pm
If you want to step it up a bit from the Crane upgrade kit, a 380" SBF road racer that I helped build (0.710"/0.670" Jones roller,~700 HP @ 7800 RPM) has had the same set of Yella Terra pedestal mount rockers in it for 5 seasons...
The CRANE upgrade kit is no upgrade in strength at all ... it merely allows the use of stud mounted rockers for getting valve train adjustability. OK for mild street rod type engines; using a girdle is really helpful.
It is considerably weaker than O.E.M. pedestal mountings.

The Yella Terra equipment is on the high-end of valve train assemblies and is great but, priced as so.
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Re: Limits of sbf pedestal mount valvetrain?

Post by cgarb » Tue Jun 26, 2018 9:01 am

40076.jpg
These are what I was talking about.
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Re: Limits of sbf pedestal mount valvetrain?

Post by Walter R. Malik » Fri Jun 29, 2018 9:56 am

cgarb wrote:
Tue Jun 26, 2018 9:01 am
40076.jpg

These are what I was talking about.
I have that type rocker arm made by Harland Sharp for a Cleveland , Modified and Big Block Ford engines. They have 1.73/1 or 1.8/1 ratio and work very well to way over 6,500 RPM using roller cam valve spring pressures.

If their metallurgy and bearings are OK they will work just fine.

Like racing shaft type rocker systems, the pushrod lengths need to be correct.
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