I am using these ported Victor heads in a race only application.Mike at B3 Racing is currently building me a rocker geometry correction kit for the Hughes rockers. Since this engine is only 493cu. in.,I would like to be able to rev this motor to 7500 if needed. It is a solid roller,with 280*/283*@ .050 w/.690 lift. It appears that I am probably looking at a 1.90" installed height.Does anyone have a solid spring/retainer combo that they wish to share? The PAC reps seemed to be involved at a seminar right now. These heads are a challenge,but they should make some power if they really flow like they claim and I am able to get the valve gear right. Thanks, Bill

Did you ask Mike at B3? Porter should have a good idea as well. I don't like making spring recommendations as I like more spring load than most and if I'm not doing the work I don't want to say how to do something.

I can tell you what I run on mine w/ a 1.90" installed height: PAC 1243s w/ ti retainers. PAC say's they're maxed out at .700" lift at that installed height, too.... 240# closed, about 625# at max lift, I think.

Whether you can spin your valve train to 7500 isn't something I think anyone can say w/o having first-hand experience w/ all the same parts (cam lobe family, pushrods, etc.). We ran mine up to 7200 w/ a COMP .650" (.655" measured net lift after lash) roller, older Hughes 1.6 rockers, and .120"-wall x 3/8" Smith Bros pushrods.

Running PAC 1326 springs at 2.00" install height. I think the retainers are +0.100", and PAC machined down the spring locators to 0.030" thick.
Running a hair less duration, but 0.726" lift with the T&D 1.6:1 rocker arms. I think the retainer keepers were stock, and running lash caps.
Got a deal on the springs from my cylinder head guy (paid about what the 1200 series cost) who had them for another project where they were not used (or the guy bulked at the cost?)
My cylinder head guy setup the install height so not sure on the keepers used, but I recalled the special order spring locators, and retainers were all from PAC.

My old setup used PAC 1325 springs, and the +0.100" Ti retainers from Crower with Manley spring locators. I think that setup may have used +0.050" keepers.

Make sure to check piston to valve clearance with that much duration.

I’d mock up the valvetrain when you get everything back and check the net lift at the valve with a spring load similar to what you’ll be using.
Then you’ll know exactly how much lift you’re dealing with, so a better decision can be made on the springs.

I’d also check with the cam grinder and get a sense of how much spring they feel you’ll need to get to 7500 with steel valves.

Without knowing any of that, I’d say you’ll probably need to figure out a way of getting to 1.950, and using something like a PAC 1225.

What is valve weight?
Lobe duration @ .020"
Net valve lift after deflection & lash?

My 511" low deck with CNC Victors and a ~.720/.690 cam @ low 270's duration was done at 7100. Somewhere on this site we have a thread where I published a bunch of installed height specs for standard length valve victors with various keeper and retainers (+.050, etc.)

I ended up using the following which is probably overkill for you but maybe close:

Springs: Isky 9999-RAD
1.600 OD, 2.00" IH, 240ish on the seat, 720ish open with ave about .90 to coil bind IIRC.

Retainers and locks:

Manley 7 deg Ti +.050 retainers and +.050 locks

Spring seat/locator:

.060" Isky (locator vs. cup gains .020 IH)

A few things come into play when setting all of this up. As you know the rocker geometry needs to be addressed or at least verified. Also take into account that the effective length of the exhaust valve stem is shorter due to the wider margin on the head of the exhaust valve. This also will tighten up you PtV measurements down in the hole.

Also ensure that you spec studs that are long enough to fully all engage thread in the head. I ended up using a mix of McMaster Carr and Indy 440 -1 kit. If you look at all of the victor threads there is a picture I posted with the various measurements of the studs kits commonly offered. Not sure why the mods don't organize that stuff in the tech archives anymore?

I'd re-post that stuff however it lives on old backup drives somewhere in my office.

Also of note: We used .040 Quickfuel air bleeds to restrict oil to the valvetrain in addition to adding a full groove to the cam. That seemed like a popular, no argument upgrade around this board lol.

Thanks all for the valuable input.Obvious that I need to do more measuring and calculating when the shafts and spacers arrive from Mike at B3.Anything less than that would just be a very expensive guess. Thanks again,Bill. Merry Christmas!!