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F-2 Speedy 03-21-2023 02:25 PM


Originally Posted by BBYSTWY (Post 4862574)
Asking because I'm not familiar with either currently....do you get the same result if you run stud girdles vs running shaft rockers? Wondering advantages/disadvantages to either option?

Thanks!

And not all BBC heads are are the same some aftermarket heads have different valve angles than a GM casting might, so you need to make sure the stud girdle is made for that specific head, I like Webster's..........that sucks for sure Dan


https://cimg7.ibsrv.net/gimg/www.off...27ad76b8ed.jpg

BBYSTWY 03-21-2023 02:37 PM

I am noticing that even when looking at jesel shaft rockers...I have engine quest iron heads that are all ported and such...the spec sheet says "they moved to a 24 degree valve angle" which I'm assuming is what I need to know but can only seem to find them as being product specific like dart or world or brodix etc....need to do some digging/calling to figure it out...

Sorry for the little hijack!! Didn't mean anything by it!

ICDEDPPL 03-21-2023 06:29 PM


Originally Posted by TeamSaris (Post 4862581)
No. Stud girdles a re a great budget way to help stabilize valvetrain. Nothing is a stable as good shaft mount rocker arms. TnD, Jesel, etc.

Mine have a lot of shims under the stands, it brings them up really high .
Jesel said it was fine , I don`t like it. Defeats the purpose of a one piece solid stand IMOP , How rigit can it be instead of resting on the head it`s 1.4" high.

TeamSaris 03-22-2023 08:34 AM


Originally Posted by ICDEDPPL (Post 4862620)
Mine have a lot of shims under the stands, it brings them up really high .
Jesel said it was fine , I don`t like it. Defeats the purpose of a one piece solid stand IMOP , How rigit can it be instead of resting on the head it`s 1.4" high.

All about the geometry. Id take some shims over bad geometry. It's still a LOT stiffer than a stud mounted rocker. Also depends on which jesel rocker you're talking about. The sportsman series isnt nearly as stable as Pro. Jesel also claims Sportsman is "not intended for marine use". We prefer prefer T&D. It's a true full shaft mounted system. It's more money, but they only have one top of the line product. And yeah, we've mad to mill the plates down sometimes and add shims sometimes. There are a million different variables. None of this is truly "bolt on".
If you feel you have "too many" shims either it's the wrong kit for your heads, your pushrod length is off, the valves werent ground correctly, its a 2.300 valve in a 2.250 pocket, blocked is/isnt decked, heads were milled, etc. Something is off.

ICDEDPPL 03-22-2023 11:52 AM

I went middle of the road , Pro aluminum with solid body . I would have preffered steel but got to draw a line somewhere in the money sand.
A. Solid Body
1.650 Pivot BB Rocker / Weight: 210g
Our strongest rocker body. Intended for use with high cylinder pressure applications such as nitrous and blowers.

To get the geometry right it had to be shimmed, my builder called Jesel and they said it`s all good . maybe I`m exagerating on the heigh . Not like I checked it.

H20 Toie 03-25-2023 12:14 PM


Originally Posted by tgorbett (Post 4862530)
Dang. Sorry to hear that. I am running those as well in my 502. Have not had any issues. However, might pick up a set and change them out before boating season gets going just for peace of mind. Would the pushrods have to be changed as well?

it all depends on the rockers you get i believe

Jim Diesel 03-26-2023 08:05 AM


Originally Posted by TeamSaris (Post 4862567)
COMP 1620 is a great replacement. ALWAYS check your geometry but we've found they're very close to the golds.

What's the go to rocker for the Mercury Racing 500-700HP now? The old Crane Golds (pre-2008) seemed pretty reliable, I noticed Teague discontinued his line of rockers and selling the COMPs, how does the COMP 1820 compare?

snapmorgan 03-27-2023 07:12 AM

I like the Crower Stainless rockers and I have always had good luck with Harland Sharp aluminum rockers. I have no idea about availibility right now though.

TeamSaris 03-27-2023 11:42 AM


Originally Posted by Jim Diesel (Post 4863069)
What's the go to rocker for the Mercury Racing 500-700HP now? The old Crane Golds (pre-2008) seemed pretty reliable, I noticed Teague discontinued his line of rockers and selling the COMPs, how does the COMP 1820 compare?

We used COMP 1620 as Gold replacements with great luck.

H20 Toie 03-27-2023 07:42 PM

Well motors are going back in this week,
Even thou it hurt having to listen to Mario at So-Cal Marine in Havasu tell me he wanted to take the motors apart i am sure glad i listened to him now,
i'm guessing that this would not have worked out in my favor in the long run

https://cimg0.ibsrv.net/gimg/www.off...db2e7b7eb.jpeg
Amazing what one part can do to the rest of the motor,

But soon to be reborn


https://cimg9.ibsrv.net/gimg/www.off...57a821c6d.jpeg


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