Roller Cams in Stock Eliminator?

Run to Rund · 01-27-2016, 12:41 PM

As noted above, most of the cam/lifter failures could be avoided if max spring pressures were something like 170 seat, 400 open. That limitation would force more lobe profile development, I suppose, but the current combination of square lobes and 550 lb open doesn't have longevity.

Dan Fahey · 01-27-2016, 01:23 PM

Quote:

Originally Posted by Run to Rund

As noted above, most of the cam/lifter failures could be avoided if max spring pressures were something like 170 seat, 400 open. That limitation would force more lobe profile development, I suppose, but the current combination of square lobes and 550 lb open doesn't have longevity.

OK see one idea of 170lb/400lb Open..
Looks reasonable..ANY other feedback...?

What is the breaking point?
I am on the NO Roller Lifter side of the argument and No Roller Rockers.
Will Stock Stamped Rockers should survive this rating?
Already saving money !

Should we also Limit Retainer Height to say 1.80 inches?

Are many cams exceeding 550 inches lift?
Most seem to be in the .400 to 450 inch range..

IHRA and NHRA has to be watching this !

Dan

Bob Mulry · 01-27-2016, 01:46 PM

Too hard for NHRA to check open pressure because all cam lifts are different..........

Set an installed height valve spring pressure limit of around 150 pounds....

Have NHRA buy an LSM valve spring testers to check installed pressure with the spring installed on the head and if the spring doesn't pass, remove it, measure installed height and use a RIMAC to confirm the pressure......

Looks pretty easy......

NHRA could even spot check the pressures....Only have to remove a valve cover...

Bob

Dwight Southerland · 01-27-2016, 01:53 PM

Well, let's look at it from the $$ side of things since that seems to be of interest.
Switch to roller cam = new billet cam, new roller lifters, new push rods, new valve springs (after all, what's the limit?), camshaft movement limiter of some sort, roller rocker arms, and then add in the machine work to allow the new maxsize valve springs that will be the next on the list to be allowed.

Reduce max seat pressure to something that will live with flat tappet lifters = new cast cam to work with the reduced pressure, new flat tappet lifters, new valve springs.

If you are smart, lobby for spring pressures that will allow common auto parts store parts to live. But I forgot, it takes too much to figure that out.

Bill Diehl · 01-27-2016, 02:20 PM

You guys are killing me with this spring pressure BS. nobody will change there cam profile, nobody wants to give up power....unless of course, you are bracket racing, Oh I forgot, that's what it is, because everybody bitches when somebody runs it out the back door.

back to the subject...you guys want to see a ton of broken valvetrain parts...limit the spring pressure and you will

next you will want an rpm limit

kansas stocker · 01-27-2016, 02:27 PM

Funny how we ran for years with stock spring pressures and it was easy to check.
Times will be slower and nobody will be able to tell the difference except in their pocket book.
Pete

Run to Rund · 01-29-2016, 02:30 PM

OK, different cams have different lifts, so the springs could be something like 170 lb. seat, and 400 lb. at some average lift, like .475. As another example of "non-stock stockers" besides the 396, look at the Z28 running 9000 rpm in stock, killing every other combination for D/S.

Pvt Parts · 01-27-2016, 02:18 PM

Quote:

Originally Posted by Dan Fahey

OK see one idea of 170lb/400lb Open..
Looks reasonable..ANY other feedback...?

What is the breaking point?
I am on the NO Roller Lifter side of the argument and No Roller Rockers.
Will Stock Stamped Rockers should survive this rating?
Already saving money !

Should we also Limit Retainer Height to say 1.80 inches?

Are many cams exceeding 550 inches lift?
Most seem to be in the .400 to 450 inch range..

IHRA and NHRA has to be watching this !

Dan

I really don't see what all the crying is about. It seems that the rules are doing what they are supposed to do... limit the cost and performance of a Stocker. The guys who are hurting parts are pushing the components beyond their limits.

Choices:

1. Back off on the cam/lifter issue and find more ET somewhere else.

2. Do whatever it takes to solve the problem. Exotic materials, different lubrication, different cam combination. If you can fix the problem, you'll have something no one has. And we all know that the cream rises to the top.

I do believe however, that valve train components should be consistent across the board. Allowing the older cars to run the same cam/lifter as the new cars would level the playing field.

Bill Diehl · 01-27-2016, 02:22 PM

Quote:

Originally Posted by Pvt Parts

I really don't see what all the crying is about. It seems that the rules are doing what they are supposed to do... limit the cost and performance of a Stocker. The guys who are hurting parts are pushing the components beyond their limits.

Choices:

1. Back off on the cam/lifter issue and find more ET somewhere else.

2. Do whatever it takes to solve the problem. Exotic materials, different lubrication, different cam combination. If you can fix the problem, you'll have something no one has. And we all know that the cream rises to the top.

I do believe however, that valve train components should be consistent across the board. Allowing the older cars to run the same cam/lifter as the new cars would level the playing field.

Excellent post

Dan Fahey · 01-27-2016, 04:59 PM

Quote:

Originally Posted by Pvt Parts

I really don't see what all the crying is about. It seems that the rules are doing what they are supposed to do... limit the cost and performance of a Stocker. The guys who are hurting parts are pushing the components beyond their limits.

Choices:

1. Back off on the cam/lifter issue and find more ET somewhere else.

2. Do whatever it takes to solve the problem. Exotic materials, different lubrication, different cam combination. If you can fix the problem, you'll have something no one has. And we all know that the cream rises to the top.

I do believe however, that valve train components should be consistent across the board. Allowing the older cars to run the same cam/lifter as the new cars would level the playing field.

Well that is the next step.
More addiction creep away from concept of Stock.
Eventually create new reliability issues.
Hence the moose call of SSer opinions...."move to SS then"

Before the Spring/Cam rule Stockers could not run with SS.
Stockers now run well under the SS index.

Think time to take a sensible step to go forward.
What is the ROI here...!!

Just
My Two Tenths err cents !

D

01-27-2016, 12:41 PM	#1
Run to Rund Senior Member Join Date: Sep 2007 Location: Henderson, NV Posts: 583 Likes: 8 Liked 54 Times in 27 Posts	Re: Roller Cams in Stock Eliminator? As noted above, most of the cam/lifter failures could be avoided if max spring pressures were something like 170 seat, 400 open. That limitation would force more lobe profile development, I suppose, but the current combination of square lobes and 550 lb open doesn't have longevity.

01-27-2016, 01:46 PM	#3
Bob Mulry VIP Member Join Date: Apr 2002 Location: Coarsegold, CA Posts: 1,016 Likes: 57 Liked 320 Times in 102 Posts	Re: Roller Cams in Stock Eliminator? Too hard for NHRA to check open pressure because all cam lifts are different.......... Set an installed height valve spring pressure limit of around 150 pounds.... Have NHRA buy an LSM valve spring testers to check installed pressure with the spring installed on the head and if the spring doesn't pass, remove it, measure installed height and use a RIMAC to confirm the pressure...... Looks pretty easy...... NHRA could even spot check the pressures....Only have to remove a valve cover... Bob __________________ Bob Mulry 7516 STK A & M Motorsports

01-27-2016, 01:53 PM	#4
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 2,001 Likes: 64 Liked 780 Times in 194 Posts	Re: Roller Cams in Stock Eliminator? Well, let's look at it from the $$ side of things since that seems to be of interest. Switch to roller cam = new billet cam, new roller lifters, new push rods, new valve springs (after all, what's the limit?), camshaft movement limiter of some sort, roller rocker arms, and then add in the machine work to allow the new maxsize valve springs that will be the next on the list to be allowed. Reduce max seat pressure to something that will live with flat tappet lifters = new cast cam to work with the reduced pressure, new flat tappet lifters, new valve springs. If you are smart, lobby for spring pressures that will allow common auto parts store parts to live. But I forgot, it takes too much to figure that out. __________________

01-27-2016, 02:20 PM	#5
Bill Diehl Member Join Date: Dec 2013 Posts: 311 Likes: 2 Liked 9 Times in 8 Posts	Re: Roller Cams in Stock Eliminator? You guys are killing me with this spring pressure BS. nobody will change there cam profile, nobody wants to give up power....unless of course, you are bracket racing, Oh I forgot, that's what it is, because everybody bitches when somebody runs it out the back door. back to the subject...you guys want to see a ton of broken valvetrain parts...limit the spring pressure and you will next you will want an rpm limit __________________ __________________ Bill Diehl B200 C/D STK

01-27-2016, 02:27 PM	#6
kansas stocker Member Join Date: Oct 2002 Location: kansas Posts: 235 Likes: 501 Liked 249 Times in 48 Posts	Re: Roller Cams in Stock Eliminator? Funny how we ran for years with stock spring pressures and it was easy to check. Times will be slower and nobody will be able to tell the difference except in their pocket book. Pete

01-29-2016, 02:30 PM	#7
Run to Rund Senior Member Join Date: Sep 2007 Location: Henderson, NV Posts: 583 Likes: 8 Liked 54 Times in 27 Posts	Re: Roller Cams in Stock Eliminator? OK, different cams have different lifts, so the springs could be something like 170 lb. seat, and 400 lb. at some average lift, like .475. As another example of "non-stock stockers" besides the 396, look at the Z28 running 9000 rpm in stock, killing every other combination for D/S.