Ravenous T\A

iTrader: (12)

What about the springs they use for the T-Rex cam?? How do those compare to the 921's?

01_SuperSlow

iTrader: (7)

WTF??? As far as I know, anything close to .600 lift and you're pushing your luck with the 918's.

Unaffliated Racing

iTrader: (15)

well see..thats where everybody is wrong..look at the specs of the spring...on the spintron that comp uses to test springs, the 918 kicks the 921's butt

also..the 918 has no problem controlling the ramps of a comp...err..LG cam

PREDATOR-Z

I wouldn't take that chance. 918's have been known to sag under extreme ramps after awhile.
With a cam like X3 where you'll see regular 7000 rpm. You'll be knocking VF door with 918's.

Louis

iTrader: (7)

918s will not work. float will occur ~ 6400, and on top of that, it is a single.

With the AFRs, were making 487 peak hp with this cam at 6500. At 7200, were still making 480 rwhp


A few other things one may take into consideration is valve weight. An 02+ Zo6 may be able to spin the 918s to 6600, but that is not true for a camaro, or some one with larger valves.

NA$TY-TA

iTrader: (21)

Your asking for trouble with 918's...... They MIGHT be a good spring with smaller cams... ive ran them myself with my first cam but heres the other thing to thing about thats the MOST important thing of all.
Comp 918's are a SINGLE spring..... what happens when that one spring breaks??? Ill tell ya what happens the valve hits the piston and if it doesnt ruin the whole motor then your out a set of heads..... not worth the risk. Its nice knowing that if **** happens and it does believe me seen it twice this year, that you have a extra spring to catch the valve and save that motor. May a little more now so you dont have to pay alot later.
But hey thats just my .02
Kyle

Ravenous T\A

iTrader: (12)

What about the springs they use for the T-REX??? Crane Cams 144832 Dual Valve Spring Set, 1.275 Diameter LS1 Replacement springs suitable to .650 lift and with more aggressive ramp-rate cams, and what about the seats??? Can they put them in without having to Remove the heads???

Louis

iTrader: (7)

There is you answer

Ravenous T\A

iTrader: (12)

But those springs are for the T-Rex 242/248 - .608/.612 - 110 lsa 3500-6700 , Thunder wouldn't offer them if they didn't work ( I hope ) They are Dual Springs too. Is 112lbs @ 1.800 not enough seat pressure?

Louis

iTrader: (7)

Based off our research, and numerous testing miles on and off the track as well as durability testing in our race cars, the Cranes do not have enough seat pressure to hold the cam. The cam needs 130+ seat, and 410+ open.

I cannot tell you what to buy but the information that you need is right infront of you. Springs are just as important as the cam you select. The price difference is not much more. If you are looking into something cost effective, look at the Patriots or the Isky 295Ds.

Ravenous T\A

iTrader: (12)

Whats the total part # on the Isky's, I tried lookin them up on there site but they have hundreds of springs and the search tool did'nt work, and how often do you need to change out the 921's? I noticed that the "GOLD"'s have to be check every 15k miles a year as stated above.

TVWilkes

Everyone's spring will need periodic checks to see if the springs are losing pressure.You can't just install a very aggressive cam and never look back.If you do this,you are asking for trouble.

Ravenous T\A

iTrader: (12)

Cool, Thanx for all the info guys, I think im gonna go with the "GOLD", so Wilkes I will be hittin you up soon (month or too). Keep me in mind too if there is a price change. I Love this site if I wasn't on here i'd be SCREWED!!!!!

Pewter'00Z28

iTrader: (2)

Yes what is the full part number for the Isky's? Anyone know the true specs on those springs?

gomer

iTrader: (13)

Btw.. I found out today that the GOLD spring that Terry sells are the springs on the new AFR heads. So they must be a hell of a spring for AFR to install them on their new heads.

Blk98Bird

Anyone tried the patriots with this cam yet, or just looking at the figures on paper? From what I hear patriot's are real good quality, and that would help drop the price quite a bit.

gomer

iTrader: (13)

I haven't ran them with the G5X3, but I ran them on my car for a while with a 234/234 .605/.605 cam without a problem. Before the .605 lift cam I ran the same springs with a TSP 231/237 .598/.595 cam for about 10k miles without a problem.

Geoff

iTrader: (3)

With all due respect, there is more to the valvesprings than just pressure. You also have to look at the natural frequency of the spring and the entire valvetrain as a system. With the right cam you might float the valves at a very low RPM if it excites the spring improperly. Conversly you might be able to rev to the moon if the harmonics of the cam and the rest of the valvetrain don't excite the springs. The point that the springs are excited is based on their natural frequency and the harmonics of the associated valvetrain.

As far as real world testing goes, we have tested the T-Rex with the Comp 921's and the Cranes. While it is true that the Comp's will generate more pressure we have seen the ability to RPM higher with the Crane springs. The lobes on the T-Rex are at least as agressive as the G5-X3, so I doubt seriously the results would be different as far as the springs go.

Disclaimer: Lou or Louis, I will apologize up front if you feel that I am jumping in your thread, this post was just meant to share my observations with everyone else.