IM wondering if I need to upgrade them. Its a flat tappet cam, The cam has .464 lift on the intake with .488 on the exhaust with 1.5s. IM using comp magnum 1.6 rocker arms, I think the lift with them is around .494 intake and .518 lift on the exhaust. The springs I have are good for .520 max lift.

Here are the specs:
1.25 od
110lbs at 1.780 installed height
300lbs at 1.280
360lbs per inch spring rate.
.520 max lift

IM thinking of using these:

1.470
120lbs at 1.780 installed height
360lbs springs rate
.540 max valve lift.

I was just reading an articule on weak valve springs. Made me wonder if mine were right for the setup.

 

I would not push valve springs to their limit, or even close. Remember, that "rating" doesn't tell you how long they'll last, only that they'll survive through the waranty period probably.

Also, note that the spec you gave was for 1.780" installed height; that's not stock, 1.700" is. So you may be .080" beyond their rating already.

I'd strongly recommend stepping up to the larger springs.

 

i'd use spring the grinder recommends or ones very similar to it, of the 2 you list i'd go with the second. also screw in studs.

 

These springs seem to have enough pressure to work well with that cam up to about 6000 rpm. But the specs don;t tell you wether they will coil bind if you just thow them on the motor with out checking for coil bind clearance.
The only way to tell is to check and verify them for coil bind height and installed height on your heads.
You need a minimum of .050 to .060" extra spring travel
at full lift to ensure that the springs do not coil bind at
high rpm.

If you want to rev it much past 5800/6000 rpm then get the better larger springs, but that cam should be all done by 5500/5800 rpm.

Again the only way to tell is to check and measure and verifly intalled height and coil bind clearance your self. Check at least 1 intake and 1 exhaust.

 

The first set is the ones my Trickflow heads came with stock. On there website a cam similar to the one I have. They suggest the 1.470 springs. I wish I would have got them when I first bought the heads.

My car overheated on the highway when the water pump went out. I read this can damaged the springs. It doesnt seem to pull as good on the very topend as before. Before I needed a rev limiter if I wasnt careful it would spin 0ver 6000. RB...what you said about them lasting has me wondering if thats whats happening. I have about 5000 miles on them.

Would dual springs be overkill?

 

No, definitely not overkill.

I do not run 1.25" springs on anything I own that's intended to run good; not even on this 305 I'm driving in my 83 car right now. I have Comp 987s on a XR264HR with 1.6 roller rockers. No high RPM problems at all, to the extent that it has high RPMs; the car goes fastest when shifted at around 5400.

 

Yeah I shift at 5500......I dont plan to spin it any higher.

 

There are 2 things that will kill a once good spring real fast.

1. too much heat.

2. Over reving the motor. (valvefloat)

I'd be checking these springs for pressure and coil bind.
They may be toast.

A bigger spring is not nessessarily better and may/ often will not
RPM higher in a said motor than a good smaller spring.
( just becuase its bigger or has more pressure)
A larger spring can/ often has a *lower natural resonance*
because of its larger mass. This often can result in unexpected valve surge within the operating range ( rpms)
than the smaller lighter spring/ retainer combo.

Fortunatly most Camshaft Co's keep this in mind when recommending their springs for a certain app.

 

Thanks for the help guys.....I did rev it over 6000 more than once by accident. IM going to do some cleanup in the bowl area while they are off. And polish the outside of the plenum and runners. The lid came out really good, I will have the springs checked after. The main reason for pulling them is I screwed up the steam holes. Replaced the head gasket once already. The bit wondered and one is really close the gasket edge. The hole is in the right spot though just to big at the opening. A few other are suspect as well. I thought I did a good job, guess not. IM loosing some coolant, not alot though, and there is condensation on the plug of the cylinder in question. Damned soft aluminum!

I never really gave springs to much thought, until i read how much power can be lost to a worn set. I will check with LPE to see what springs they suggest with the cam too.

 

I searched two forums but couldn't find all the threads I was looking for but. . . I would replace the Trick Flow 1.25" valve springs ASAP! Here's one other one and where I replied about mine. There have been others too.

https://www.thirdgen.org/techbb2/sho...ght=tfs+spring

I ran a set of Erson springs until last month and then upgraded to the 1.46" springs from TFS. They sent the wrong keepers because these springs needed a 1.780" installed height. They sent the standard keepers and I needed the .050 keepers to raise the springs.

Chevy 23d heads
1.460 in. Springs
1.460 in. O.D. double with damper
125 lbs. at 1.780 in. installed height
376 lbs. at 1.180 in.
420 lbs. per inch spring rate
.600 in. max valve lift
Valve Locks: 7 degree + .050 in. machined steel on all other spring versions

Point is, after TFS supposedly giving me a deal, I could have bought all Comp Cam stuff since I had to get a $25.00 set of keepers to make the TFS stuff work.

I wouldn't trust them springs! Read the thread, exactly the same head and springs and both broke a top round off of one of the springs. Call me paranoid but when others have identical problems as I have had (and I know the lift wasn't too high and RPM's weren't a factor) I get that way. Everyones luck is different but if it saves your engine then I'm glad I spent my time posting my experiences!

 

SMasterson....Thanks for taking the time to post that. I missed that thread, I cant beleive they sent you the wrong parts! Its there head, and spring setup!

So you have the dual springs, Are you running a roller cam? would it be cheaper to get the comp stuff then adding the trickflow springs? I wonder if i need the dual springs? Is that what the 987 comp springs are dual? Have to take a look at the comp website.

Gonna do a couple searches to see if I can find any more info on the trickflow springs.