12 Sec GTA

the 487/501 is too much for stock springs.. so is there a spring that will take the lift but still fit in the OE head pocket?

I assume that CCA-986s need the pocket machined, right?

These springs are for a set of stock iron heads, with no chance of machine work. Temporary use on an engine that sees a LOT of nitrous.

8Mike9

I know COMP and Crane make 1.25 springs good to over .5 lift, thing is, do you have clearance on top of the valve guide to run such lift?

The heads may need to come off for machining the guides down anyway, then studs may as well be done too...then a valve job...may as well do some porting while they're off...

Oh well, afternoon projects rarely are.

89formula35O

i used competitors 2300 springs on my setup. i cant remeber there site though.

Vader

Gee, if this were on a carbureted, SFI, or TBI engine I might be able to help. I'm not sure that TPI engine springs are the same... ¿?

Dyno Don

iTrader: (7)

Manley makes a spring and retainer that will work. I'm using them on my vortecs. I don't have the # with me but I can post it in the morning.

12 Sec GTA

Thanks, I'd appreciate it.

Dyno Don

iTrader: (7)

Here ya go: Manley part#22410-16 springs...#23652-16 retainers
These retainers lift the installed height .050 giving a installed pressure of 120-130# closed... 340# open. This will allow .520 lift safely (but be sure you check it).
Disclaimer: your results may vary...LOL

12 Sec GTA

Do you happen to remember how much the springs & retainers ran you?