Solid roller spring suggestions please

[Bob Hollinshead]

I have an unknown solid roller cam we are going to try in my Son's sbc 377. Cam specs are 298@.020 266@.050 .445 lobe on the intake, 306@.020 268@.050 .420 lobe on the exhaust. Thinking the shift will be at 7500. 11/32 2.08 / 1.6 stainless valves. We have a rev kit. I have no idea what valve springs would good. We have 1.95 of installed height with standard locks. Any thoughts on this? Thanks

[pcnsd]

Check with Stan Weiss.
I recall he did some work for DV and produced a program that recommended valve springs based on various inputs. Diameter, installed height, seat and nose pressure ,etc. Used a data base of various manufactures products.

[mt-engines]

I have an unknown solid roller cam we are going to try in my Son's sbc 377. Cam specs are 298@.020 266@.050 .445 lobe on the intake, 306@.020 268@.050 .420 lobe on the exhaust. Thinking the shift will be at 7500. 11/32 2.08 / 1.6 stainless valves. We have a rev kit. I have no idea what valve springs would good. We have 1.95 of installed height with standard locks. Any thoughts on this? Thanks

Skip the rev kit.. run a PSI DR424 or run a -.050 lock and run a basic HER611 herbert spring and shim it.

[BillK]

I would look through a few cam catalogs online and find cams similar to that and see what they are recommending.

[Turbobuick6]

What Rocker Ratio?

[Walter R. Malik]

I have an unknown solid roller cam we are going to try in my Son's sbc 377. Cam specs are 298@.020 266@.050 .445 lobe on the intake, 306@.020 268@.050 .420 lobe on the exhaust. Thinking the shift will be at 7500. 11/32 2.08 / 1.6 stainless valves. We have a rev kit. I have no idea what valve springs would good. We have 1.95 of installed height with standard locks. Any thoughts on this? Thanks

On a cam very similar to those specs, I have run PAC-1343 springs at 1.930" installed height.

There are probably several which could fit that bill.

[frnkeore]

On a similar cam (270 @ .050) but, 1.76 RR (.710 valve lift), Bullet recommended 220/230 seat pressure and 575/620 open.

WRM's 1343 PAC's fit that bill.

[CamKing]

What Rocker Ratio?

Without the rocker ratio, no one can make an intelligent recommendation.

[Bob Hollinshead]

What Rocker Ratio?

Without the rocker ratio, no one can make an intelligent recommendation.

1.5 ratio on intake and exhaust. Mike, also would you take a stab at what a safe valve lash would be? Thanks

[steve cowan]

I have run the PSI 1277 springs for years and been happy with them.
I just upgraded to a PSI 1.30" diameter spring looking for better stability in the valve train to turn 8000rpm.
The springs are not much more expensive but I had to get a custom set of retainers from xledyne which were expensive because of the 11/32" stem.
If you are doing the full set up might be worth going smaller max life springs to suit.

[Bob Hollinshead]

I have run the PSI 1277 springs for years and been happy with them.
I just upgraded to a PSI 1.30" diameter spring looking for better stability in the valve train to turn 8000rpm.
The springs are not much more expensive but I had to get a custom set of retainers from xledyne which were expensive because of the 11/32" stem.
If you are doing the full set up might be worth going smaller max life springs to suit.

Steve is that 1.30 spring a dual spring? This is a mostly street deal so we are hoping for some longevity. I was hoping the Rev kit will help. Crower full body lifters.

[steve cowan]

I have run the PSI 1277 springs for years and been happy with them.
I just upgraded to a PSI 1.30" diameter spring looking for better stability in the valve train to turn 8000rpm.
The springs are not much more expensive but I had to get a custom set of retainers from xledyne which were expensive because of the 11/32" stem.
If you are doing the full set up might be worth going smaller max life springs to suit.

Steve is that 1.30 spring a dual spring? This is a mostly street deal so we are hoping for some longevity. I was hoping the Rev kit will help. Crower full body lifters.

I am using the DR 427 RML spring which is a 1.30" diameter dual spring.
I am a bit shorter on installed height compared to your set-up but should be able to find something for your application.

20231123_144113.jpg

20231123_171023.jpg

[Turbobuick6]

Depending on what the application of this engine and what your goals are, you have a couple options.

If this is going to be a "max effort" kinda deal where you are trying to make as much HP as possible, I would highly suggest looking at the PAC-1427H conical spring.

If this is more of a street engine combo where you are looking for longevity, I would suggest the PAC-1243.

Both springs would want roughly a 1.900 Installed height.

1427H - 1.870 IH
210 seat and 540 open

1243 - 1.900 IH
240 seat and 598 open.

[CamKing]

What Rocker Ratio?

Without the rocker ratio, no one can make an intelligent recommendation.

1.5 ratio on intake and exhaust. Mike, also would you take a stab at what a safe valve lash would be? Thanks

Since there's no way to know how aggressive the lobe profiles are, I would go with the ISKY 9935 springs without the rev-kit, or the ISKY 9915 springs installed at 1.950" with the rev-kit.

Without knowing the lobe profiles, there's no way of knowing what the correct lash is.
I would start with a Hot Lash on .015" to run it in. Then you want to increase the lash in .002" increments, until it gets noisy or hurts the power.

[Bob Hollinshead]

Without the rocker ratio, no one can make an intelligent recommendation.

1.5 ratio on intake and exhaust. Mike, also would you take a stab at what a safe valve lash would be? Thanks

Since there's no way to know how aggressive the lobe profiles are, I would go with the ISKY 9935 springs without the rev-kit, or the ISKY 9915 springs installed at 1.950" with the rev-kit.

Without knowing the lobe profiles, there's no way of knowing what the correct lash is.
I would start with a Hot Lash on .015" to run it in. Then you want to increase the lash in .002" increments, until it gets noisy or hurts the power.
[/quote

Thanks!