ultraz

I'm doing a vortec head swap on my 86 L98. Researching, I'm seeing that vortec heads can go up to .460 or a .480 lift. Either way, I have a factory LT1 cam from a 97 bird. But thats a .447/.459 loft i believe with 1.5 rockers. But my L98 has comp cam roller tip rockers that cam with the L98. I do believe they are 1.5 ratio. Now, I would like more lift. But rather get bigger cam, like LT4 or hot cam.
SO.. I know I need to get the comp cams 787 retainers/locks. I already have multiple sets of blue and yellow springs. Yellow's are LS6 original that are good for a .570 lift on LS heads. Blue's are LS3 for .550 lift. LS6 springs are thicker coils and taller uninstalled. I've mic'd both the blue and yellow springs.
Now, the valve seals ot says online to use are Total Seal p# st2015. Seems they are impossible to find. And with the vortec heads having valves with a fatter stem vs LS heads.. what are my other options to the st2015 valve seals? Do I have to use umbrella or standard Teflon seals? I don't want to have to pay a machine shop. What needs to be machined anyways? What other parts do I still need to be able to increase valve lift?
I'm trying to get the motor to reach easy 300hp a cheap as possible. With buying the heads from LKQ and the LT1 cam and LT1 24# injectors, and already having the valve springs, dog bones and spider retainer for 87+ roller lifters to accommodate the LT1 cam. So besides gaskets.. I've got just $150 invested. I'm keeping the tpi intake. I'm in the process of porting the crap out of the tpi plenum, runners and intake manifold. I refuse to spend $500 on Edelbrock manifold and another $500 or more on Siamese runners. So now be spending $60 for the 787 locks and then same on vortec manifold. Should stay under $300 for parts before cost of tuning her up.
WIth the LT1 cam having similar duration to the L98 cam, the lift is a lot more. But adding vortec heads to flow better, should be somewhat drive able with adjusting the dizzy and maybe adding an aftermarket fuel# regulator.. At least I'm hoping. Car is actually a 86 Vette and I'm hoping will be better on my aging body for a DD vs my 98 ws6 t56. What I'm concerned about is my fun level... For now my dd's are an 04 Tahoe (which is getting a mild LQ9 with 243 heads, tbss intake sd cam etc) And my 98 WS6 has LS6 top end, 7k + rev limit and I shift at 7k when racing, plus having 4.10s.. car is built and fun. And I mean built. All tubular, brembo fronts, etc. Its beyond a blast to drive and I do drive her hard!
I also have my 85 z28 also. But that build is gonna be going on for a looong time. Its getting a nice little LS1 matted to the th400 and 3.73 gears that I'm not changing out from when it was running with the monster carb'd 383 stroker motor. But so much left to do.

sofakingdom

iTrader: (1)

To put the LS6 springs on a Gen 1 SBC, no machine work is needed. All you need is the "adapter" retainers from Comp (787), and their matching hardware. And of course proper shimming to achieve the right installed height. It's REALLY EEEEEEEZZZZZZY.

TPI will prevent an excessive "fun level". Don't worry too much about that.

For seals, try Fel-Pro 72861. https://www.summitracing.com/parts/fel-ss72861

ultraz

Their vortec heads as stated in my post. But I did find a few decent YouTube videos so once I get to that step I'll try to make a little post of what I did to achieve. And none of those guys talked about shimming it's just using the right retainers and locks to achieve.520 lift. Which would allow me to install LT1 cam with 1.6 rockers or maybe if extra funds allow, the zz4 cam.

gwarren007

iTrader: (1)

Shimming allows you to get the spring pressure right and the installed height correct or both.

sofakingdom

iTrader: (1)

Zackly.

The stock installed height for those springs is 1.80", which allows a lift of up to about .550" if the cam isn't too violent. IMO the difference between .550" and .570" is insignificant... acoupla pieces of copy paper. You can shim them to a slightly lower height to get more control of the valve, at the expense of reducing "max lift". I would not go lower than 1.75" however. That would sacrifice .050" of "max lift" in exchange for around 15 - 18 lbs on the seat, which in some circumstances, would be well worth it. It's almost impossible to have "too much" seat pressure, in the real world. Sure, you can invent scenarios where that could happen, but it's not a concern with stock springs, especially.

You might find that one or more valves on your particular heads (there's ALOT of variation among heads in such areas) won't make the full 1.80" without shims. I would NOT in any case recommend putting NO shims under the springs; they'll eat a hole all the way to China through the casting. Always put at least a .015" hardened one in there. If that makes any of em come out to less than 1.80", set em all up to that lesser height, whatever it is, as long as it's above 1.75". If they won't set up to 1.75" or above WITH a thin shim, consider having a racing machine shop knock a small amount of metal out of the spring pocket; just enough to open the tightest one up to 1.75", although of course that kinda defeats the cheeeeepness purpose in the first place.

ANY factory small block cam is well within the capability of LSx springs installed at their stock height. I'd just put em in at 1.80" and be done with it, if possible. After all, most stock LSx cams, especially the later car ones, are FAR more aggressive than the ones that came in the 55-2000 motors.

I doubt there's any material difference in performance or longevity between the 2 versions of LSx springs that the OP has. AFAIK the yellow ones will replace the blue ones in any stock application. That said, I'm not a fan of re-using used stock springs of ANY kind; but with any of the stock LT1 cams, they're probably "enough" even with some miles on em.