SStolen

iTrader: (22)

Getting ready to install the TR230 and can't decide whether to just go with their Cam kit which includes Comp single 918 springs, 772 Comp titanium retainers and TR hardened pushrods or go with something like the "manley valvetrain." I see that all of the time in people's sigs. Is it any stronger or more reliaiable than the Comp Kit from TR? I know it is cheaper, I saw it on the Scoggin Dickey website. I'm unsure about whether it will work or not because the valvespring height and load specs are different than the 918's. How does that affect the set-up? What about quality? Titanium retainers are titanium retainers and chromemoly pushrods are chromemoly pushrods right? Why are some pushrods and retainers cheaper than others? Aren't chromemoly and hardened the same?

What about REV double springs? Someone told me they wear down the lobes of a cam faster though because they have more springload.

Why are the Comp 877 dual springs $90 and the Comp single 918's $160? That makes no sense. Aren't the dual springs better? Is it because the 918's drop in without fitment?

I just heard the 918's are noisy. If they will work and are good quality then thats what I'll go with. But if the manley valvetrain is also good quality and cheaper then I can do that too.

Sorry for the long, annoying post.

Nickn20

had 918s with the TR230 cam experience valve float pretty bad, after about 2k miles
went to the REV dual springs and have worked flawlessly for 5k miles now..... I like the revs.

2001CamaroGuy

iTrader: (6)

well....to start off with...

yes....for the most part, a chrome molly push rod is a chrome molly push rod.....any "good" company's will work fine....



now...the springs and retainers are different...

Comp 918s for example are a "new" style spring designed FOR the LS1

Comp 987s (a duel spring....I have these) are a "standard" spring....they are not designed for the LS1 and require machine work of the head (larger seat) to fit......

one is "cutting edge", will only fit a limited number of engines, and thus will cost more (same reason our forged cranks are $1500+ vs. forged SBC cranks are $500+) while the other is "old school"

then, the retainers for the 918s are different than the 987 (they fit different springs....like ford rims and chevy rims)

BUT....

while yes up front the 987s are cheaper to buy, once you add up the machine work and added parts needed to work with them, they end up costing about the same (actually a little more)


the REVs seem to be a really nice spring (I have not heard of any problems) but they are exspensive and your still stuck with the small seat (limited seat pressure)...


I'm glad I did the 987s....it cost me a little more to have to work done to the heads and they are louder because of the spring pressure (shut the valve harder) but I like knowing that I have a lot of safety factor in my valve train.....

And.....

if for some reason I ever need more pressure, I can always just remove the inner spring (they are an inner, an outer, and a dampener in between) and replace it with the inner from the 985 and have an added 40lbs of open seat load.....

KGSloan

i've got the rev's in my car with the tr230 cam. they seem to work really good. also they make me feel better about not droping a valve since they are dual springs and should have a backup if one of them breaks.

gillbot

iTrader: (27)

918's in mine and it's running fine. Thunder recommended they be changed after 10k though.

MyLS1Hauls

iTrader: (2)

Geoff from Thunder specifically said that is not true. He said they ought to be good for 24k without a problem. Do a search for him on 918s and see what he says.

gillbot

iTrader: (27)

When I spoke to Thunder on the phone (forgot who I spoke with, this was long ago) they said 10k to be safe, or get them tested. I'm sure they can go longer but if I pull them at 10k for testing, I'd just go ahead and replace them.

99 Black Bird T/A

iTrader: (4)

Why fool with 918's when you can do dual Rev's or 987's when there are sticky's about 918 problems at the top of the internal engine section?

While many run 918's without problems, seems like someone always ends up with a 918 spring problem pretty often. While problems can happend with any spring they happen more often with 918's than the 987's or dual Rev's.

One of the most common causes for engine problems are valve spring issues. Why take a chance?

Have 987's. I want dual springs with an aggressive cam. I'd also consider the dual Rev's.

SStolen

iTrader: (22)

The heads don't need to be machined to fit the REVS so the spring seat pressure will be no better than the 918's. Someone told me that this almost defeates the purpose of a double spring. What does seat pressure have to do with the performance of the valvetrain? He said it is still worth doing but not as good as the 987's.
But, it is not worth it to me to pull the heads and pay for machining and an expensive head AND cam gasket kit for $250 vs. the cam only gasket kit which is 40 bucks since I will be getting heads next year anyway which will make the machining obsolete and force me to get new head gaskets which I switch to S2 heads.
Are double springs louder, the same or quieter than single springs or does it come down to the spring itself?
Do double springs wear down the cam lobes faster because of more pressure and if so, does it really matter that much in a hydraulic motor? Thanks- Mike W.

FAST99Z

hich came out first the 918s or the 941s??

2000RATA

Go with the REV's. The seat pressure is higher than the 987's. Open pressure is as well.

Zatlanta

I put in the Manleys.. 350lb loaded up to .600 lift. If you plan alot of track time, then go with duals.. otherwise, consider a good single for street.

99 Black Bird T/A

iTrader: (4)

The 918's came out after the 941's, I'm 99.9 percent sure.