Hydraulic Flat Tappet Spring Pressure

[YO7_A66]

 I am curious about those of you who run 150-155lbs (360-365lbs open) of valve seat spring pressure on a hydraulic flat tappet cam. Have you had any issues (cam wear, lifters bleeding down, etc.) on a street car?

I made a rocker arm swap (stock stamped to 1.65) last Winter in my 340 and at that time I had a vendor specify that I needed to use their 120lbs/310lbs springs. So I installed them and drove the car this year and I noticed that the engine would not run any higher than 5600rpms after this swap and the valve train seemed noisy at cruise. I discussed this with two different Mopar engine builders and they both told me that I needed more spring pressure due to the 1.65 rocker ratio and 2.02" valves. They both suggested 150-155lbs on the seat and 350-375lbs open. (Note: my cam card showed 135/300 with 1.5 rockers. But I was not asked and I did not even think about checking what the cam card suggested at the time that the springs were specified). I plan on keeping the WOT shift points at about 5800-6k rpms.

 I just finished with my spring swap and all the installed heights came out to show 153lbs average (1.810"-1.824" IH) on the seat and 361/362lbs average open pressure (per the spring chart) at .540" lift.

I may not get a chance to drive the car again this year due to the weather, but I just wanted to make sure that there is nothing else that I should be looking at before Spring.

Notes: My cam designer (S.B) said that the core will handle these spring pressure with no problems. Comp says that my hydraulic lifters max out at apx. 360lbs but should be fine. My rocker arms are Yella Terra 1.65's that are rated for 600lbs. My push rods are Manton Series 5 (5/16" x .118" wall, 275,000psi), and I use Brad Penn Green Oil.

Thanks

[Cudakiller70]

I am doing my first cam change on a 340. This is all new to me and I'm still learning. I'm installing a flat tappet hydraulic and planning on using stock rockers right now. My springs are listed 120/315.
You mentioned noisy valve train, from what I've read not having enough (hydraulic) lifter preload can cause this. I'm installing a Hughes whiplash and they recommend   .080 - .095  lifter preload. To get the geometry right I might need new pushrods also, but learning as I go we'll see.
Just guessing here, is it possible you are floating the valves because lifters aren't pumping up enough? Maybe you need more preload? 
My car is not running yet so I don't know and am just guessing based on what little I've read, others here who do know I'm sure will chime in. Good luck! 

[YO7_A66]

 My Comp lifters are spec'd at .020"-.060" preload.
 I started out the season with 3/4 turn (.031") preload and then changed them to 1 turn (.042").  It did not seem to make much difference in the noise. I was told that the noise is typical from roller rockers but since this is my first set, I am just not sure. I also had issues with the rockers hitting the tops of the valve covers too which I fixed. I have to say that the noise was less by the end of Summer after some driving time.
 I think that my main problem was that I should have had 135lbs on the seat with the 1.5 rockers, but I was running all Summer on 120lbs on the seat with the larger 1.65 rockers.

 Thanks for the response.

[barnett468]

comp cams standard lifters are total crap . they may kill the cam themselves or make moise at the very least . i use crane anti pump lifters.

use high quality oil with over 1100 ppm of zinc.

if you break the cam in with that much spring pressure it may very well kill it.

[734406pk]

Check to see if any push rods are contacting the cylinder head. This can happen with >1.5:1 rocker arms as they move the push rod inward towards the rocker shaft. Too much pre-load can cause valve float as well as low spring pressure and faulty hydraulic lifters. What is the part number or the Comp Cams lifter that you are running BTW?

[YO7_A66]

I use Brad Penn Green Oil and I am not breaking in the cam or lifters. I have excellent push rod clearance due to B3 Racing making me a geometry kit. These are the Comp High Energy lifters. I swapped out valve springs which puts me close to the Comp max spring pressure recommendation.
I was just curious what lifters others were using with 150-155lbs seat pressure.

 Thanks

[734406pk]

I use Brad Penn Green Oil and I am not breaking in the cam or lifters. I have excellent push rod clearance due to B3 Racing making me a geometry kit. These are the Comp High Energy lifters. I swapped out valve springs which puts me close to the Comp max spring pressure recommendation.
I was just curious what lifters others were using with 150-155lbs seat pressure.

 Thanks

Understood. There are different Comp Cam Hydraulic Lifters and they have different recommended pre-load adjustment. What p/n are you running?

[YO7_A66]

I don't have the part number in front of me but the Comp tech told me .020"-.060". I have mine set to .03".

[734406pk]

OK. There are these:
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=867-16&Category_Code=PMHFTL
And These:
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=882-16&Category_Code=HTHFTL
I'm wondering which one you have.

[YO7_A66]

I found my notes and I am running the Comp High Energy 822-16 lifters.

 This is another thread that I started on this subject over on Moparts:
 http://board.moparts.org/ubbthreads/ubbthreads.php/topics/2203894/hydraulic-lifters-spring-pressure.html#Post2203894

[734406pk]

I found my notes and I am running the Comp High Energy 822-16 lifters.

 This is another thread that I started on this subject over on Moparts:
 http://board.moparts.org/ubbthreads/ubbthreads.php/topics/2203894/hydraulic-lifters-spring-pressure.html#Post2203894

Lots of good info there on moparts! IMO Pro Magnum lifters would be a better choice than the Hi-Tech series. It's all speculation until you try them or change to a solid cam and lifter set up. You already have the adjustable rockers, it may be the best/easy choice for your setup.

[YO7_A66]

I am going to try my existing lifters to see how they act. If they can't keep up, then I will be going with the Hy-Lift Johnsons mentioned in that thread.
 Thanks

"""Per Hy-Lift Johnson Sales: The B-2330S is no way comparable to Comps lifters. This is the best lifter made for the 340. These lifters can achieve 7000rpms, seat pressure up to 160lbs & open pressure to 450lbs. Pre-load is .030" and the seat height is close to the other brands. He said that this lifter is very popular with you High End Mopar Builders. $224 a set of 16."""

[Topcat]

I am going to try my existing lifters to see how they act. If they can't keep up, then I will be going with the Hy-Lift Johnsons mentioned in that thread.
 Thanks

"""Per Hy-Lift Johnson Sales: The B-2330S is no way comparable to Comps lifters. This is the best lifter made for the 340. These lifters can achieve 7000rpms, seat pressure up to 160lbs & open pressure to 450lbs. Pre-load is .030" and the seat height is close to the other brands. He said that this lifter is very popular with you High End Mopar Builders. $224 a set of 16."""

Good move!

Spending money on quality lifters is a must IMO.

I'm running EDM solids from Johnson.

[734406pk]

I am going to try my existing lifters to see how they act. If they can't keep up, then I will be going with the Hy-Lift Johnsons mentioned in that thread.
 Thanks

"""Per Hy-Lift Johnson Sales: The B-2330S is no way comparable to Comps lifters. This is the best lifter made for the 340. These lifters can achieve 7000rpms, seat pressure up to 160lbs & open pressure to 450lbs. Pre-load is .030" and the seat height is close to the other brands. He said that this lifter is very popular with you High End Mopar Builders. $224 a set of 16."""

Good luck and post the results! I have always used solid lifters for over 6K rpm. It would be interesting to see how the hydraulics work out. 340 Mopar, The Best small block ever made IMO! 

[YO7_A66]

 My engine is back together now but Winter has hit. It will be a while until I get a chance to see if these lifters will hold. But I will check back in when I find out.
 Thanks everyone.