GT40p F77E ported cylinder heads studs and guide plates installation

[@jackstrife9158]

When I cut stud bosses down in the guide machine, I have made a few pilots on the lathe that I use for this. You threaded the pilot into the existing 5/16 boss and use that to level the head so when you cut the boss correctly, you are also squaring it up to the valve stem. So when you drill and re-tap that boss, it will be perfectly aligned with the valve stem, your geometry comes out correct in the end. So to recap, install threaded guide into the boss. Level head in the machine. Drill and tap boss for 3/8 or 7/16 stud(whichever the customer chooses). Install new threaded pilot(3/8 or 7/16 thread again whichever customer is wanting to run) cut stud boss down to desired hight for new studs and plates. I've done quite a few gt40 heads and 360 magnum heads and found this method works very well.

[@arturozarate1752]

I must have explained that to over thousands of clients! The Crane kit allows for the rocker pedestal off axis and the side to side of the pushrod. ON THE MONEY! YOU WILL BRAKE A LOT OF STUDS! A LOT! I haven't thought of this is 12 maybe 15 years. I still have the Crane conversion kit I used on my OE 93 Cobra GT40's. You absolutely have to square up the rocker stud boss. Good luck and good job catching. I bet there isn't a single other mention of this on KZbin.

[@garykarenmcgruther6386]

i use to work at Automotive machine shop. its a standard practice where i worked at to check all machined surfaces to be squared up, then cut down the bosses to certain height after measuring the studs to be used. the issue we found was hardly any holes drilled and tapped from the factory was always off a touch, we had to use adjustable guide plates to align them up correctly, then number that plate to that cylinder, then tack weld it together. that's alot of customers said no on doing them back then. it was simply to expensive. today its not.

[@arturozarate1752]

@@garykarenmcgruther6386 yes sir. With the guide plates being 2-piece the adjustability helped keep the valve guides from wearing by centering the rocker arm load on the valve tip. Which also kept the valve job sealing. Smh....I've even had Viper clients decline the work when converting to T&D shaft rockers.

[@ferdinandcuevas8457]

That's exactly why You need to check everything out before the final assembly even if it takes more time ! Then You have the satisfaction of having a quality build that You can stand by ! Thank You for sharing Your knowledge and experience 🤔 . 🇺🇲🇵🇷🦊👍

[@supertruckertom]

Ready to go assembled AFR SBF 165 or 185 heads are looking more and more attractive

[@servediocylinderheads]

That is great, you will still need to have them gone over. Guides, seat concentricity, spring load and coil bind need to be checked.

[@billyjack8119]

Just use Iskey adjustable guides and you dont have to weld them when your done. Dont forget to check under your roller rocker for clearance because they are thick guide plates. I mill the pedistals down some to help with that. You will also notice that with the one piece design the rocker is not centered on one valve tip correctly. Adjustable is the way to go. Everyone makes the best stuff and when you cant make it work its your problem not theirs. I've thrown away more halfass parts in the past 30 years that you wouldnt believe.

[@bobcuomo5122]

Charlie, They make 2 piece guide plates to line up push rods .

[@servediocylinderheads]

I have seen that I think I have only used them once.

[@arturozarate1752]

Right on Charlie!

[@theshed8802]

You just can't rely on anything can you? Either every guide plate is wrong, or every bolt hole is in the wrong place from the factory. Good video Charlie. Regards Greg

[@hotrodray6802]

Two sets of guide plates....

[@theshed8802]

@@hotrodray6802 i was just looking at another video where they use 2 piece guide plates that you weld together once you get your geometry correct. I haven't measured any heads, but I'm suspecting that Ford have played with valve position and rocker geometry by a few thou for some reason.

[@garykarenmcgruther6386]

Charlie, use the same guide plates as the AFR heads use, then tack weld after each is numbered.

[@servediocylinderheads]

My Afr guide plates are solid flat plates.

[@stuartwall8212]

The OEM 5/16 rocker arm bolt gets little respect when upgrading valve springs. I wonder if that tilted pad is as much a culprit as the size. Also, I wonder if that small tilt with OEM bolt will alter the final position of the rocker arm after it gets its little bit of torque.

[@606garage4]

Doesn’t the rocker bosses need to be cut down anyway? I’m Pretty sure ford recommends .230

[@dennisford2000]

And then how close are the push rods , centered? I would bet against it.

[@servediocylinderheads]

Been fixed and delivered. Thanks

[@hotrodray6802]

🔔😎 Very good info. Thank you for posting. Are 3/8 studs ok? What about adjustable guide plates then spot weld? Thanks again Charlie. 👍👍😎

[@servediocylinderheads]

Depending on spring load and rpm yes.

[@jplperformance9073]

I need some 3800 supercharged heads done???

[@servediocylinderheads]

Sounds fun but I have no experience with those heads. Fyi

[@jplperformance9073]

@Charles Servedio cylinder head porting & flowbench can you recommend someone. Light porting and install bigger valves 1.80/1.84& 1.50/157.

[@servediocylinderheads]

@@jplperformance9073 I do not know anyone who specializes in those heads. I am up for a challenge.