What springs to go with XFI (.600" lift) Lobes?
08-21-2006, 08:21 PM
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What springs to go with XFI (.600" lift) Lobes? What valve-springs would you recommend to go with to properly complement a Comp-Cam w/ XFI lobes, producing lifts (w/ 1.7 rocker) of .590"/.600"? Cam is a 214/218, going in a DD. I am only going to rev to ~6200 RPM. Heads are AFR205s, and I am using the STOCK LIFTERS. Thus, the gonzo stiff springs (ie, PRC-Duals) are going to be waaay too much for the stock lifters to handle longterm, and I'm not going to swap to Comp-Rs.
So, with the stock lifters, revving to ~6200rpm, XFI lobes (.600" lift).... Would Comp 918s work? Manley -1428s? AFR-8017s?
Whatever spring is recommended, I will be using Ti Retainers.
Thanks!
So, with the stock lifters, revving to ~6200rpm, XFI lobes (.600" lift).... Would Comp 918s work? Manley -1428s? AFR-8017s?
Whatever spring is recommended, I will be using Ti Retainers.
Thanks!
08-21-2006, 09:03 PM
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These are the springs that come on the Dart Pro 1's for LSx's. A friend of mine found this information and sent me the link. (Thanks vettenuts 
) The spring information can be found in the link below, the PSI springs are part # PSILS1511, on page 18. The PSI information starts on page 17. These are a premium beehive spring and are marketed as Isky Toolroom springs. Give it a minute to load or it'll lock up on you.
http://www.cvproducts.com/cv/catalog/catalogs/M-P.pdf
) The spring information can be found in the link below, the PSI springs are part # PSILS1511, on page 18. The PSI information starts on page 17. These are a premium beehive spring and are marketed as Isky Toolroom springs. Give it a minute to load or it'll lock up on you.http://www.cvproducts.com/cv/catalog/catalogs/M-P.pdf
08-22-2006, 08:42 AM
#3
I have been using as set of PRC platnum dual springs on a 233\233 .595\.595 lift 112 LSA cam for 31,000 miles without any problems.. using stock lifters..the lifters have 118,000+ miles on them now..stock lifters are strong sir....contact Tesas Speed & Performance ..
Last edited by slt200mph; 08-22-2006 at 11:20 AM.
08-22-2006, 09:05 AM
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Observation - wouldn't a cam with high lift for that short duration warrant a dual spring like the Patriot Golds the AFR205 heads come with out of the box? I ran a custom cam 216/200 with ~.590 lift.
What valve spring preasures is Comp requiring for the cam?
What valve spring preasures is Comp requiring for the cam?
08-22-2006, 11:01 AM
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Collapsing stock lifters with the heavier-duty dual PRC/PP/AFR springs seems to be pretty well documented on here (ie, much more common than on other springs). It appears the spring open-pressures are just too much for the stock lifters to handle with any amount of confidence. Hence, since I'm not going to be running a cam with lifts anywhere near the .650" maxlift rating of the PRC/PP dual springs, IMHO its overkill (and detrimental to the stock lifters). Figure there's a more friendly spring choice that will suit my application & provide (likely) better longevity and reliability.
Vettenuts has done a bunch of legwork looking into the stock lifters' capabilities to withstand greater spring pressures. Doesn't look too reliable from his postings....
Vettenuts has done a bunch of legwork looking into the stock lifters' capabilities to withstand greater spring pressures. Doesn't look too reliable from his postings....
Last edited by 02RedHawk; 08-22-2006 at 11:34 AM.
08-22-2006, 11:20 AM
#7
Originally Posted by 02RedHawk
Collapsing stock lifters with the heavier-duty dual PRC/PP/AFR springs is pretty well documented on here. It appears the spring open-pressures are just too much for the stock lifters to handle with any amount of confidence. Hence, since I'm not going to be running a cam with lifts anywhere near the .660" maxlift rating of the PRC/PP dual springs, IMHO its overkill (and detrimental to the stock lifters). Figure there's a more friendly spring choice that will suit my application & provide (likely) better longevity and reliability.
I am pretty happy with the 31,000+ mile life span (and still growing every day) of my PRC dual springs. I am getting ready to do another cam and head swap and will use the Comp 921s this time with a higher lift cam. (LSX lobe) I look for a long life on those springs too. I Will replace the 118,000+ mile stock lifters at that time. My car sees the red line daily..no problems with it ... my car gets started and warmed up every morning for 5 minutes before I take off for the day..I think that is one reason that I have no oil consumption and long valve spring life.. the car is a daily driver ..
