Progress Thread Komo's 1990 GT - Parts Gathering Purgatory & Home Remodel

gkomo · Mar 7, 2026

I ordered the Scorpion 1019’s.

AeroCoupe · Mar 7, 2026

I run them on my 331 but have tall aluminum valve covers so no issues with clearance.

gkomo · Mar 7, 2026

AeroCoupe said:
I run them on my 331 but have tall aluminum valve covers so no issues with clearance.

I ran TFS twisted wedge heads 170cc (same as my current ones) with 1.7 rockers on my last fox which was a 331 and used my stock valve covers but I had an engine builder do the entire long block so I don’t know all the specs from memory anymore. I probably have my build sheet in a binder somewhere.

I don’t recall which rockers I used but want to say the TFS 1.7’s. I think the oil baffle may need to be modified to run stock valve covers.

Noobz347 · Mar 7, 2026

gkomo said:
I ran TFS twisted wedge heads 170cc (same as my current ones) with 1.7 rockers on my last fox which was a 331 and used my stock valve covers but I had an engine builder do the entire long block so I don’t know all the specs from memory anymore. I probably have my build sheet in a binder somewhere.

I don’t recall which rockers I used but want to say the TFS 1.7’s. I think the oil baffle may need to be modified to run stock valve covers.

I think I'm picking up what you're putting down here but historically, the Scorpions are just bulky. The ratio isn't what causes baffle clearance issues but just the physical [heft] of the Scorpion rockers.

TFS head have an extra 3/8" clearance if I remember right.

AeroCoupe · Mar 7, 2026

There is more to them than the Comp Cams magnum's I run in the T-Bird but I would say they are no more bulky than the old Crane Cams ones I had or my buddy's Hartland Sharps. Maybe I am missing something there?

Noobz347 · Mar 7, 2026

AeroCoupe said:
There is more to them than the Comp Cams magnum's I run in the T-Bird but I would say they are no more bulky than the old Crane Cams ones I had or my buddy's Hartland Sharps. Maybe I am missing something there?

Maybe. Or I am... I recall that I had a choice when I did my build. Rockers that claimed non interference with the OEM baffle and the Scorpions recommended by the builder.

I run the AFR 185s BTW.

AeroCoupe · Mar 7, 2026

T-Bird has the pro magnums on AFR 185’s with tall Motorsport covers with Comp Cams valve girdles.

Mustang has Scorpions on Edelbrock Performer RPM’s with tall Motorsport covers with Jomar valve girdles.

I have not run roller rockers with stock covers so no data there.

Noobz347 · Mar 7, 2026

For me, tall covers were not an option due to the Kenne Bell.

gkomo · Mar 8, 2026

I don’t want to mess with different valve covers so I may cancel my scorpion order and buy the TFS rockers. Research tells me they are shorter than the scorpions.

Noobz347 · Mar 8, 2026

gkomo said:
I don’t want to mess with different valve covers so I may cancel my scorpion order and buy the TFS rockers. Research tells me they are shorter than the scorpions.

Nothing wrong with that but again, I think you have an extra 3/8" of clearance with those TFS heads.

gkomo · Mar 8, 2026

From what I was reading up on, the scorpions would be suuuper close to needing to dimple the valve covers/use a thick gasket/etc. I think I’d rather just get some that I am mostly confident will fit without fiddling around with stuff.

I do think the baffle needs to be modified no matter what though.

Edit: scorpion order cancelled

gkomo · Mar 10, 2026

I was able to cancel my Scorpion order, so now back to researching Rockers.

Are Harland Sharp rockers good? They say they are head specific for the TFS Twisted Wedge Heads:

ORIGINAL Small Block Ford Trickflow Twisted Wedge

Fits: Trick Flow Twisted Wedge Street Special Notes: Designed like no other SB Ford roller rocker on the market Our head specific rockers are designed for a perfect fit, thus eliminating valve guide wear and friction. Which means maximum horsepower for you SB Ford application

harlandsharp.com

I wrote TrickFlow an email asking about Rocker Arms and they replied any quality rocker arm will work fine and they don't need to be head specific like the Harland Sharp ones linked above.

The heads come with 3/8" rocker studs. For my street driven application will these be sufficient or should I convert to a 7/16" rocker stud/arm setup? It sounds like either will screw into the head, just need to pick which sized rocker arm/stud combo i want, although buying 7/16" rocker studs adds like another $120 to the cost.

AeroCoupe · Mar 10, 2026

Umm yeah man, Hartland Sharp are some of the best.

gkomo · Mar 10, 2026

AeroCoupe said:
Umm yeah man, Hartland Sharp are some of the best.

Run the supplied 3/8" studs and get 3/8" rockers, or spring the additional money to go with 7/16" studs and 7/16" rockers (same price).

AeroCoupe · Mar 10, 2026

As long as where the studs screw into the heads that is also 7/16". Makes no sense to have 7/16" rocker studs that have 3/8" threads where they go into the heads.

I will say that if you have the stock TFS springs on the TW 170's and a stock cam then 3/8" will be up to the task. Engine builder would be able to tell you better.

gkomo · Mar 10, 2026

AeroCoupe said:
As long as where the studs screw into the heads that is also 7/16". Makes no sense to have 7/16" rocker studs that have 3/8" threads where they go into the heads.

I will say that if you have the stock TFS springs on the TW 170's and a stock cam then 3/8" will be up to the task. Engine builder would be able to tell you better.

From what I understand both the 3/8 and 7/16 studs will thread into the head so (I think) it’s just either using the 3/8 studs that came with the heads and getting 3/8 rockers. Or buy aftermarket ARP 7/16 studs and 7/16 rockers.

Sounds like 3/8 setup will work for my current use case. Just wonder if it would be worth ‘upgrading’ to 7/16 now just in case things get crazier down the road.

I’m still not 100% sure what stock springs for the TFS are because the set I bought come with ‘upgraded valve springs’…?

AeroCoupe · Mar 10, 2026

What I am driving at is if the threads in the head are smaller than the rocker arm stud where the rockers go on then the weak point is the threads that screw into the head. If the head has 7/16" threads where the rocker arm stud installs then I would pop for the 7/16" setup. If the head has 3/8" threads then I don't see the point of going to 7/16" on the upper part of the rocker arm stud.

I want to say most modern aluminum heads are 7/16" base with some having 3/8" but I am not sure. Both my cars run 3/8" rockers with lifts of 0.568 and 0.598 but I also have rocker arm stud girdles. Those will not fit under a stock height valve cover that I am aware of.

gkomo · Mar 10, 2026

Oh man I’m dumb, I should just go with the 7/16” studs:

So the heads are already threaded for 7/16 and step down to 3/8 on the upper side of the bolt. Might as well just go 7/16 the whole stud.

Shoulda just researched this before.

Noobz347 · Mar 10, 2026

Good to know.

I wonder though, whey would somebody have reason to use the 3/8 studs in a head threaded for 7/16?

gkomo · Mar 10, 2026

Noobz347 said:
Good to know.

I wonder though, whey would somebody have reason to use the 3/8 studs in a head threaded for 7/16?

I think the real question is why does Trick Flow provide 3/8 studs with the heads if they are threaded for 7/16?

Now I gotta spend money on new 7/16 studs.

Progress Thread Komo's 1990 GT - Parts Gathering Purgatory & Home Remodel

now i can hopefully expect to receive the shaft

lube between the nut and the face. I know my lubes

now i can hopefully expect to receive the shaft

Stangnet Facilities Maint Tech... Er... Janitor

lube between the nut and the face. I know my lubes

Stangnet Facilities Maint Tech... Er... Janitor

lube between the nut and the face. I know my lubes

Stangnet Facilities Maint Tech... Er... Janitor

now i can hopefully expect to receive the shaft

Stangnet Facilities Maint Tech... Er... Janitor

now i can hopefully expect to receive the shaft

now i can hopefully expect to receive the shaft

lube between the nut and the face. I know my lubes

now i can hopefully expect to receive the shaft

lube between the nut and the face. I know my lubes

now i can hopefully expect to receive the shaft

lube between the nut and the face. I know my lubes

now i can hopefully expect to receive the shaft

Stangnet Facilities Maint Tech... Er... Janitor

now i can hopefully expect to receive the shaft

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