Denny McLain

Need a little advice here………..

Currently using Comp 977 spring/titanium retainers with 1.65 rockers and the lift is .630 on my 99.99% street driven car. Makes great power for a hydraulic setup, but the problem is the springs last less than a couple of months before they go away and I loose power up on top. Hell, all I drive the car is to workout, grocery store, car shows and twice a year track outings

Obviously I need to find something better. Possible options:

• New springs/retainers that are better
• Hydra Lift kit (TFS heads and my old hydra lift kit doesn’t fit - does any??)
• 1.52 rockers (had the same problem with 1.6 rockers and thought it was just that set of springs)
• Titanium valves to reduce weight
• Completely different camshaft with less lift.

Anyway, I don’t know what else I can try. Better springs that last longer would be the first choice with the second being a Hydra Lift kit that adds a little more tension as I doubt the springs loose that much that quickly.

Suggestions!!

rskrause

Something from the Comp 26000 series or the Manley "NexTek" line is what I have used.

Rich

Denny McLain

How much lift are you running?? I had no problems with the comp 977's with a 234/242 cam that had .570/590 lift. Hard to believe that either .610 (1.6 rockers) or .630 (1.65 rockers) would have that much more of an effect on the springs. Then again, I was running a hydra lift kit also.

AdioSS

Denny, have you measured the spring pressure before installation and after they get weak?

Comp says that the 977s are recommended for only .600" lift. It looks like you'll need to have bigger spring pockets cut to allow a better spring to fit. Going with longer stem valves should help things also. It looks like the Comp 9290 springs would work for your current combination. The OD is just .075" wider and the pressures are very close, but it is good to .650" lift. They are coated to reduce heat, so the price might be higher. But they should last longer too.

If you can get a HydraRev kit to work, then that should help a bit.

GM decided to use Titanium valves on the new Z06 with a hydraulic roller valvetrain. That engine needs to be able to last 100k miles. So that makes me think that an engine that sees a lot less miles a year should be fine with Titanium valves.

I wouldn't even consider dropping down to lower ratio rockers if you are making the power that you want. In fact, if you have the piston to valve clearance, I would consider stepping UP in rocker ratio. Comp has some very good 1.7 and 1.8:1 ratio stud mount rocker arms, but a shaft rocker setup would be better.

SStrokerAce

Ditto, or ISKY tool room springs. I'm a fan of the 26000 Comp stuff it's just not cheap.

The 26112 Comp spring would work well since it was designed as a Marine BBC spring. The 9905 Isky Tool Room Spring or even th 9925.

All depends on how aggressive the lobes are as well, but more spring life is going to be had out of better quality spring wire. The lift sure isin't helping but yanking out lift is going to hurt your top end so I doubt that is part of what you want to do.

Hell I'm a fan of the beehive stuff i'd look at one of those as well. You've had enough problems with lifters reducing spring pressure might be a good way to go and maintain valve control. The Morel's can take 190# on the seat without trouble but the less it takes to control the valve the better.

Bret

SStrokerAce

Cheston,

Part of his issue could easily be the tighter run with coil bind. .025 to coil bind on a 977 is probably not making that puppy happy if the installed height is still 1.850" I'm guessing there is a lot of heat in there caused by that. Take out .025-.030 of that valve lift and those springs would probably live a lot longer.

Some setups can run a tight coil bind with zero problems and some even run better. To do that you can't run a damper in between the two springs and the spring wire and the rest of the setup has to be matched.

Bret

SStrokerAce

Rich is in the .600-.610 range.

You might gain a ton of spring life by going to a 1.52-1.55 rocker or another cam that has less lift at the lobe.

Bret

AdioSS

Bret, what do you think of the 9290 coated valve springs for his application?

Denny McLain

You know how hp addicts are......... I'd rather do other springs and/or a hydra lift if that works. Don't mind changing springs like once a year, but once a month is a bit much.

Thanks guys......... good stuff!

INTMD8

I'm having a similar problem myself. Running 977's with Ti retainers at 1.86 installed height. Cam is 218/218 .571 .550 (XFI lobes)

After 1500 miles I pulled a spring to check it because it was floating/bouncing valves at 6000rpm's.

It measured at 135 seat 375 open. (about 20 less than what its rated at)

I was thinking of trying the 26120 beehives, which I could set up at around 160 on the seat.

Or I see that PSI makes a 1.45 (ish) od spring that I could set up with 170 on the seat 400 open.

I like the idea of the beehives, but not really sure if I want to experiement with them on my car since changing the valvesprings is such a bitch.

SStrokerAce

Cheston,

I can't get a price on the coated ones out of my price sheets so it's hard to say if you can even get them.

The 929 wouldn't be bad, but it's still going to drop 20lbs on the seat and leave you at 140 seated so not much help there.

Denny,

The Hydra-Rev is not going to do anything for you with this issue. It's not going to save the spring life or control the valve any better... I still think they are a waste of time and money on a Hyd Roller anything.

Your at the point were valve spring life is so short that replacing springs is not very cost beneficial even at $120 a set. The bad news is the Isky Tool Room or 26112 Comps are $415-$375 a set, they will last a lot longer and will not drop as much pressure on the seat as fast.

I'm certain that most of your spring life problem is the lift and RPM teamed with the 977 springs. I'm betting those things are steaming hot after a few runs, no wonder they loose so much pressure so quickly.

At that price point it's hard not to look at other options as well. The larger beehives need longer valves so those part numbers are out of the question unless you have the +.100 valves in there now. The 26918's would also be a tight fit since you have the .630" lift and to get the right installed height would be a bear.

You might want to look at the 26921 springs that the LS1 guys use, they have the room in there you need to run what you are doing.

INTMD8,

The valve length is really your only barrier to installing the 26120's in there.

FWIW I don't worry too much about the beehives, i've run a lot of sets and have yet to have any problems with them.

Bret

INTMD8

Well, I think I've found my spring.

I've been talking to PAC springs

http://www.valvespring.com/pacracing.htm

and they said they supply ISKY with a beehive spring pt # TVS1220 (which I couldn't find on their website, but I'll call tomorrow)

1.445 OD

1.800 176lbs

1.200 415lbs (which I think would make it a 398lb/in rate)

1.150 coil bind.

I'll probably install them at-

1.83 164lbs, which would put me at 391 over the nose with .571 lift.

SStrokerAce

That sping sounds interesting. ;-)

The PAC and PRO PAC names are awfully familiar.

Bret

INTMD8

Yes, it does sound interesting.

Could work on Denny McLain's car too

1.84 160lbs closed

1.21 410lbs open (.630 lift, and .060 to coil bind)

IllusionalTA

Wow.. http://www.racingsprings.com/movies/test004.avi