.528/.557 Purple shaft solid spring pressures.

[MOPAROFFICIAL]

I've used both these cams, Street strip, and I just wanted to share what I've found to work best for seat and open pressures. I'd like to hear what everybody else has been running.

I run 11/32 5.025/5.011 valves
150lbs seat @1.80
330 open @.500

1.437 Paw double springs, same as engle's dbls they sell for their .5-.575 lift solids. Probably made by pioneer or someone like that.

Anything less than those pressures has shown float or loss of valve control.
Everything I build I always either pull the rocker set myself and check the wear patterns on the valve stems or tell the customer to do so.
I still break the cam in with 120lbs seat and maybe 280/300 open.fyi

 

[33IMP]

Are you referring to bigblocks or smallblocks?

 

[TT5.9mag]

Everything will loose control of the valve at some point. List the rpm the valves float for a complete picture.

 

[MOPAROFFICIAL]

I'll mention that when I 1st used these cams 25 yrs ago I was told by the guys at mancini racing to use the 857 spring? ,a single w damper. Those only yield 120 seat and 290 open, maybe...
Bad recommendation on them, but at the time I didn't know **** about spring pressures for lift/rpm.

I rev about 64-6800 rpm and cruise freeways at 3500 or so fwiw

 

[MOPAROFFICIAL]

Are you referring to bigblocks or smallblocks?

Small block section, but yes 150 seat on a big block is what was said as the norm for those .. but I'd go 160 min.

Fwiw Those paw dbls were sold under sbc hyd roller applications. They peak around 350-360 lbs max lift.

 

[33IMP]

Small block section, but yes 150 seat on a big block is what was said as the norm for those .. but I'd go 160 min.

Fwiw Those paw dbls were sold under sbc hyd roller applications. They peak around 350-360 lbs max lift.

Thanks. My bad, I didn't notice the thread section.

 

[MOPAROFFICIAL]

Thanks. My bad, I didn't notice the thread section.

All good.
Those comp 995 springs that they also recommend.... ehhh.... I don't.

 

[mderoy340]

I also run a hydraulic roller double spring on my SFT setup.

 

[Dart Frog]

I found the same thing I had to switch springs three times on my current Mopar performance mechanical lift cam before I could eliminate valve float. I ended up with a LS upgrade PAC spring for hydraulic roller. It has about 350 lbs with my lift and the float is no more. More spring than I thought it would need

 

[Killer6]

Not a SB, but as to Mopar's recc'd. springs, a guy working in parts at the dealer had raced His Omni with the biggest cam back in the early '90's. He had all the stuff from the catalog, long tip followers retainer/spring pkg. etc., couldn't keep it from kicking out rockers....went to the next cam down & lived with it. Basically those used SB springs at that level, I'd have been curious to see what it took to solve that issue, just more spring load or was it a dynamics issue.....