Valve Spring Opinion Wanted

Running a  502 with Mildly ported P51s, Current springs listed Below
would this be a good setup ?? What would you recommend ??



Springs:
part#221447

NexTek Valve Spring, Drag Race, Roller Cam - 1.677 OD triple, max lift .800, 350lb @ 2.000
Super Stock, Pro Mod, Comp Eliminator racing triple valve spring for roller cams up to .800 lift with 2.000 install height. Set of 16.

   1.677 OD triple
   .635 ID
   .800 max lift
   350 lbs @ 2.000 installed height
   895 lbs @ 1.270 open pressure
   Spring rate 746 lbs
   Coil Bind 1.160
   Also available fully polished for maximum fatigue life - SEE Listings

nothing wrong with this set up

Jeff,

Tread carefully here.... That's a lot of valve spring that you are proposing for P-51 heads. If you use that spring, please be advised that they will require new bigger spring seat cups, and you will probably have to re-machine your heads in order to handle that bigger o.d. of the cup and spring.

I'd rather see you use the PAC #1224 or 1324 which is a 2.000" installed height double spring. The neat thing about it is that it coil binds at 1.070"-1.100" instead of the usual 1.150". That allows for a little more lift. 275 lbs @ 2.000" and 810 lbs @ 1.150". Also it is a smaller diameter and you won't have to buy the bigger cups and re-machine.

Charlie

agreed...I do not think that application has to have a triple. The 1224 pac and the manley 'blue stripe' do a good job even on the A460's heavier valves.

thanks for the replies, i thought they might be a bit much and was thinking of checking pressures with the inner spring left out,
and see what kind of numbers i came up with. But you both are going in the right direction, you know how it goes, i already had the
triples and hoping   

guess i need to see if anybody wants to make a trade   

Check'em with the small inners out....may be good to go.

will do, thanks

if iv done the math right, i was figuring about 7400max rpm, does that look right to you guys ?

figuring on short shifting to sav some wear and tear. Probably around 6600-6800, do you think the PACs could go the whole 7400 if i wanted ?

Jeff

Yes they could. Like what Lem said, that's the spring that comes on the TFS A-460 heads, and it's valves are heavier than yours, so I feel pretty confident that they can go 7400 rpm with no problem.

Charlie

If your opting for the triples and are getting rid of the inner spring, I think I would check them both at the seat and at full lift for pressures just to be safe.

thats the plan, now i just need the time to get back to it   

jc10000rpm wrote:thats the plan, now i just need the time to get back to it   

Pay attention to what I said about the size of the 1.670" springs, the matching seat cup and re-machining the head in order to take that larger cup. You've got potential problems there you are going to have to deal with. Measure everything.

Charlie

When using a double instead of a triple you can usually use an inner spring seat locator and don't need to re-machine the diameter of the spring pocket any larger. With a triple, locating off the spring O.D. is the only option.