Built a 402 with ls3 heads and put the prc .650 spring on. It's a dialy driver and now I'm thinking of getting the EHT spring because of the longevity. What do you guys think? Cam is a 229/236 .621/.624 114 LSA with gmpp 8000rpm rated hydrolic lifters and Texas speed 5/16 chrome moly push rods. Do you guys think its a good investment?

Thanks,
John

http://www.texas-speed.com/p-473-pre...pring-kit.aspx

http://www.texas-speed.com/p-474-pre...pring-kit.aspx

 

I have the exact same question, with the newly designed springs is there still a difference in longevity? I have heard the .675 springs are more susceptible to being set up wrong, but on lifts <.630 or so is there still a remarkable difference in longevity between the two spring sets?

 

i like the new PRC .675" spring kit

 

I was told that the .625 .650 and .675 lift PAC spring are all made with the same material and only the EHT spring go though that other treatment that makes the longevity about three time batter.

 

Called them. Aaron recommended the .650 set of springs, although he did state the newer .675 kits were redesigned to be less tempermental about setup. He said is checked and ran properly the .650 set could offer up to 40k miles.
However their website still lists the .675 as the only spring that is "EHT", and there seemed to be good data from a while ago that those springs lost less rate over use than competitors springs, but not sure about comparing against the prc .650 kit. I know for a while they were offering free upgrades to the eht kit since they were out of the regular spring kits, and they said the maturing or processing of the .650 kits would take some time (not sure what that proces was, likely proprietary info). But if they were shipping .675 kits in place of .650 surely that means they would last at least as long in low lift applications?

 

^Yes this is true the .675s will offer good life just like the .650s. I just believe the .650s will be adequate for your application and will last for many miles. I do recommend checking them at the 25,000 mile mark to make sure everything is still up to specs, but I will say I have had many customers report beyond 40,000 miles on these springs with no issues whatsoever.

 

how does one know if they have the newly designed 650 or the older 650??

 

We have not changed the .650 springs.

 

oh ok, i was under the impression you guys changed the way they where made.... good to know they where not

 

^Pm sent!