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Valve train points, what is it?


turbogrill
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Hi,

 

Curious about the valve train fixed value. If I change the cam I most likely need to change the valve train to work with that cam, would that be additional points?

 

For instance on my old car I had to do:

- Different valve springs and spring retainers

- Different lash pads

 

Would that be extra points? Most cam swaps that I know of requires stiffer springs.

 

Or is modified valve train something else? (Like SOHC->DOHC or something crazy)

 

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21 minutes ago, TiredBirds said:

I think the only hit would be if you went up to a roller system or changed the ratio... 1.5 to 1.6. I don't think springs take points. Pretty sure everybody swaps springs out, like timing chains and what not. 

 

That makes sense, essentially something that would give you a performance boost regardless of the cam.

 

14 minutes ago, Ray Franck said:

Cam & lifters =+ 50 

Valve train = pushrods, rockers, followers, springs, & valves that are not OE speck = an additional 50 points.

 

Why would lifters be included and not springs? Changing lifters with cam sounds like a domestic problem. (changing springs with cam is an import problem) 

 

edit:

Found the tech desk (https://champcar.org/tech/knowledgebase.php?article=137

 

Q.
Per 2020 BCC: "Camshaft or valve train, non-OE: 50 pts per engine"
* Does this rule mean non-OE camshaft AND rockers is 50 points per engine?

 

A.
The "camshaft or valve train" rule is defined by the word "or" here.
So your cam swap is 50 points and that includes the lifters (as they come as a set in one box most of the time), OR your valve train is 50 points which is the pushrods and rocker arms.
Intake and exhaust valves are included with the cylinder head.

 

Nothing about springs or lashpads or retainers. Will ask them.

 

Edited by turbogrill
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2 minutes ago, turbogrill said:

 

That makes sense, essentially something that would give you a performance boost regardless of the cam.

 

 

Why would lifters be included and not springs? Changing lifters with cam sounds like a domestic problem. (changing springs with cam is an import problem) 

 

   Never heard anyone recommend running old lifters or followers on a new cam, domestic or import.

   Installing a large enough cam to require a spring change is going to increase power enough to warrant more points. This is the way it has been seperated and done, if you feel it should be changed you can use the petition process. 

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30 minutes ago, Ray Franck said:

   Never heard anyone recommend running old lifters or followers on a new cam, domestic or import.

   Installing a large enough cam to require a spring change is going to increase power enough to warrant more points. This is the way it has been seperated and done, if you feel it should be changed you can use the petition process. 

 

Just want to make sure I don't cheat.

 

It would surprise me if everyone is running OEM springs. 50pts is a lot as it is.

 

I assumed springs was included since otherwise your are very limited to low lift cams. (I guess I could do a custom grind with high duration and low lift).

 

thanks

 

 

 

 

Edited by turbogrill
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2 minutes ago, turbogrill said:

 

Just want to make sure I don't cheat.

 

It would surprise me if everyone is running OEM springs. 50pts is a lot as it is.

 

I assumed springs was included since otherwise your are very limited to low lift cams. (I guess I could do a custom grind with high duration and low lift).

 

thanks

 


OEM springs are not open, they need to be OE for the year make and model to be 0 points. 

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3 minutes ago, red0 said:


OEM springs are not open, they need to be OE for the year make and model to be 0 points. 

 

OE replacement works, right? Not OE as in buy from the dealer?

 

I would assume rebuilder springs you get from machine shop would work (like SBI, Federal Mogal, Sealed Power, Melling, Etc). These can have small variations in coil count and height, as the blanks are meant to fit several different engines and alter the spring in the setting process to fit the applications OE performance (open and closed pressure). Compared to a real race spring, at least on springs built for radical lift, the difference should be noticeable. 

 

@turbogrill In a practical sense I replace these when I have a reason to remove the head (warped head gasket, valve job or something else forcing the head to the machine shop). I get my stuff from the "rebuilder" market when much cheaper and or OEM is not easily accessible, Rock auto actually has decent access and pricing on these "rebuilder" parts.  I would think most of the better teams would take the same precaution, and although they are OE type I doubt their machine shop goes to the dealer to buy them when you say "give it a valve job and replace the springs".  I would also not expect any of the "rebuilder" springs to come back beehive units with damper springs and clearly microfinished (if that is what you had in mind), which should be pretty easy to spot. 

 

Also just because the more aggressive grinds have more lift doesn't mean the head actually flows better up there. You can get a high duration cam reground to slightly reduce the peak lift, if you are worried about your spring bind height. Since they are already grinding the normal cam to a larger profile, nipping part of the cam nose off wouldn't require a new blank or reweld\base circle reduction (for cams with no blanks). Fairly easy rework. 

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12 minutes ago, Black Magic said:

 

OE replacement works, right? Not OE as in buy from the dealer?

 

I would assume rebuilder springs you get from machine shop would work (like SBI, Federal Mogal, Sealed Power, Melling, Etc). These can have small variations in coil count and height, as the blanks are meant to fit several different engines and alter the spring in the setting process to fit the applications OE performance (open and closed pressure). Compared to a real race spring, at least on springs built for radical lift, the difference should be noticeable. 

 

@turbogrill In a practical sense I replace these when I have a reason to remove the head (warped head gasket, valve job or something else forcing the head to the machine shop). I get my stuff from the "rebuilder" market when much cheaper and or OEM is not easily accessible, Rock auto actually has decent access and pricing on these "rebuilder" parts.  I would think most of the better teams would take the same precaution, and although they are OE type I doubt their machine shop goes to the dealer to buy them when you say "give it a valve job and replace the springs".  I would also not expect any of the "rebuilder" springs to come back beehive units with damper springs and clearly microfinished (if that is what you had in mind), which should be pretty easy to spot. 

 

Also just because the more aggressive grinds have more lift doesn't mean the head actually flows better up there. You can get a high duration cam reground to slightly reduce the peak lift, if you are worried about your spring bind height. Since they are already grinding the normal cam to a larger profile, nipping part of the cam nose off wouldn't require a new blank or reweld\base circle reduction (for cams with no blanks). Fairly easy rework. 

OE means “the factory part or a part that is equivalent to the factory part”. Like if you went to autozone and said “I need (part name) for a (make) (model) (year)” they would give you an OE part. OE is always legal. If you deviate from OE in the drivetrain, it will cost you points. If you are running valve springs that aren’t OE, you aren’t legal unless they are claimed.

Edited by enginerd
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8 minutes ago, Black Magic said:

 

 

Also just because the more aggressive grinds have more lift doesn't mean the head actually flows better up there. 

True!

 

But a high lift cam will have a higher average lift and will be "open" more in the lower regions as well. Using a dial indicator I measured my mild lift cam and my aggressive lift cam and even if they have similar duration the high lift cam had a way higher average lift. The high lift cam didn't spend much time in the high lift region but it did spend a lot of time in the "medium" lift region where my head absolutely flows well.

 

I wish I have saved the plots.

 

To make a low lift cam have the same "average" duration as a high lift cam you would need almost a square cam :)

 

It's also nice to use off the shelf parts that has been proven.   

 

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22 minutes ago, Black Magic said:

 

OE replacement works, right? Not OE as in buy from the dealer?

 

I would assume rebuilder springs you get from machine shop would work (like SBI, Federal Mogal, Sealed Power, Melling, Etc). These can have small variations in coil count and height, as the blanks are meant to fit several different engines and alter the spring in the setting process to fit the applications OE performance (open and closed pressure). Compared to a real race spring, at least on springs built for radical lift, the difference should be noticeable. 

 

@turbogrill In a practical sense I replace these when I have a reason to remove the head (warped head gasket, valve job or something else forcing the head to the machine shop). I get my stuff from the "rebuilder" market when much cheaper and or OEM is not easily accessible, Rock auto actually has decent access and pricing on these "rebuilder" parts.  I would think most of the better teams would take the same precaution, and although they are OE type I doubt their machine shop goes to the dealer to buy them when you say "give it a valve job and replace the springs".  I would also not expect any of the "rebuilder" springs to come back beehive units with damper springs and clearly microfinished (if that is what you had in mind), which should be pretty easy to spot. 

 

Also just because the more aggressive grinds have more lift doesn't mean the head actually flows better up there. You can get a high duration cam reground to slightly reduce the peak lift, if you are worried about your spring bind height. Since they are already grinding the normal cam to a larger profile, nipping part of the cam nose off wouldn't require a new blank or reweld\base circle reduction (for cams with no blanks). Fairly easy rework. 


So, I just looked up valves on rock auto for a Honda engine. It would be my opinion that the first one that says "original style" is 0 points. The second one that says "High performance replacement with .5mm oversize, high flow, swirl polished stainless steel, can use STD valve seats but must be machined for new valve size" would be 50 points for non OE valve train. 

image.thumb.png.77fbb673fe632340df0be8d93b5e8584.pngimage.thumb.png.f8786d36d4869b17b3ab937d09444e16.png

 

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27 minutes ago, enginerd said:

OE means “the factory part or a part that is equivalent to the factory part”. Like if you went to autozone and said “I need (part name) for a (make) (model) (year)” they would give you an OE part. OE is always legal. If you deviate from OE in the drivetrain, it will cost you points. If you are running valve springs that aren’t OE, you aren’t legal unless they are claimed.

 

I was thinking the "rebuilder" network of parts from the suppliers I listed being that sort of equivalent. Issue being the big box stores generally don't offer engine rebuild parts. Autozone only shows valve springs for NC miata that I would consider "aftermarket", and are most likely just universal aftermarket spring listing (for all cars, not just miata). The machine shop supplier books being the best match to an autozone I could think of for this (what rock auto pulls from when they have stuff).

 

15 minutes ago, red0 said:


So, I just looked up valves on rock auto for a Honda engine. It would be my opinion that the first one that says "original style" is 0 points. The second one that says "High performance replacement with .5mm oversize, high flow, swirl polished stainless steel, can use STD valve seats but must be machined for new valve size" would be 50 points for non OE valve train. 

image.thumb.png.77fbb673fe632340df0be8d93b5e8584.pngimage.thumb.png.f8786d36d4869b17b3ab937d09444e16.png
 

 

Makes sense. The product lines sold to machine shops as drop in replacements when doing a rebuild being ok. The products sold specifically for performance applications requiring you to go out of your way to fit being points. 

 

Edited by Black Magic
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Thanks for answering this, saved me 5 penalty laps :)

 

Also my cam in my old chumpcar has a high llift with a modified valve train to accommodate that, good thing it has a VPI of 150...

 

edit:

I still don't understand why non-OEM lifters are allowed for 0 pts??? 

Edited by turbogrill
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26 minutes ago, turbogrill said:

True!

 

But a high lift cam will have a higher average lift and will be "open" more in the lower regions as well. Using a dial indicator I measured my mild lift cam and my aggressive lift cam and even if they have similar duration the high lift cam had a way higher average lift. The high lift cam didn't spend much time in the high lift region but it did spend a lot of time in the "medium" lift region where my head absolutely flows well.

 

I wish I have saved the plots.

 

To make a low lift cam have the same "average" duration as a high lift cam you would need almost a square cam :)

 

It's also nice to use off the shelf parts that has been proven.   

 

 

"square" cams are a thing in the circle track world, where lift limited cams are part of the rules. 

 

I would doubt you have to go that crazy for a reasonable performance cam. Measure your actual coil bind height on your springs and compare to the max lift of the cam you are looking for. Often "aftermarket" springs are "required" for mid sized cams simply to give extra margin to accommodate for poorly setup springs. New "OE"\"OEM"\"Rebuilder"  springs might further help the issue, as you can rate these and setup the head to provide more max lift via proper (low side of good) closed spring pressure. You might need little if any peak lift reduction\squaring. 

 

Unless you have a mega monster cam....

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1 minute ago, Black Magic said:

 

"square" cams are a thing in the circle track world, where lift limited cams are part of the rules. 

 

I would doubt you have to go that crazy for a reasonable performance cam. Measure your actual coil bind height on your springs and compare to the max lift of the cam you are looking for. Often "aftermarket" springs are "required" for mid sized cams simply to give extra margin to accommodate for poorly setup springs. New "OE"\"OEM"\"Rebuilder"  springs might further help the issue, as you can rate these and setup the head to provide more max lift via proper (low side of good) closed spring pressure. You might need little if any peak lift reduction\squaring. 

 

Unless you have a mega monster cam....

 

 

 

Datsun:

The old datsun cam was a turd, so the difference between stock cam and a 200whp cam is huge. Stock cam is 0.390" and my cam is 0.535".

The stock springs bind at 0.460" or something.

 

NC:
As you say it seems more like a "nice to have" for the NC. I thought it was a must, so just becomes a reliability issue :)

 

Interesting with the "square" cams, would imagine the valve train would not like this.

 

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  • 3 months later...

It seems crazy to have to pay 50 points just to run the springs that come with your camshaft that you are already paying 50 points for, that means you pay as much for a camshaft as you would pay for a turbo. Of course, valvetrain is per engine so if you are paying the 50 points you may as well get the most of them with big valves, good racing springs, Ti retainers, and if you are building American iron I assume you could run a full Jesel shaft rocker system.

 

So how about flycutting pistons for valve clearance with the cam you already paid 50 points for?

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40 minutes ago, mhr650 said:

So how about flycutting pistons for valve clearance with the cam you already paid 50 points for?

If porting heads and intakes are no points and shaving heads for compression is no points I don't see why this would be points. But, there should be some obligation to prove they are stock pistons in case the the series uses a borescope like they did in impound at COTA last year. 

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1 hour ago, mhr650 said:

It seems crazy to have to pay 50 points just to run the springs that come with your camshaft that you are already paying 50 points for, that means you pay as much for a camshaft as you would pay for a turbo. Of course, valvetrain is per engine so if you are paying the 50 points you may as well get the most of them with big valves, good racing springs, Ti retainers, and if you are building American iron I assume you could run a full Jesel shaft rocker system.

 

So how about flycutting pistons for valve clearance with the cam you already paid 50 points for?

It seems crazy that when swapping a DOHC head one gets the cams and valvetrain in the 100 point swap but if one puts some aftermarket heads on a domestic v8 they also get hit with 50 points for the valvetrain that is free on the other guy's engine. And then 50 points more for the cam he likely wants to run.

 

100 points for the DOHC head swap, 200 points for the equivalent V8 change.

Edited by Bandit
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Springs should either go with the heads or the cam, pick one.  Simple as that. charging for every associated part is double jeopardy.  A cam is worthless without the springs it requires.

Valvetrain should be if you want to throw on a set of high dollar roller rockers.

You don't get charged 10 points for a suspension link and then 10 more points for the two heims you put on the end of it do you?

 

For reference, from the tech desk...

 

suspension with heim.png

Edited by 67Mustang
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Go to any cam website and look up a cam, You're likely to see "Springs required"...  And this isn't just the Elmer Fudd "Well sure yr engine needs valve springs" Yes..  It's the type of "Yes" indicating that springs capable of working with the operating range of this camshaft are required.  We all know that.  So why would you have 50 points for a cam swap in the rules and then not say a word about the valve springs that the cam will require???

 

Point is, you don't have to have fancy billet roller rockers to run a big cam but you do have to run appropriate springs for it.

 

 

 

springs required.png

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I'll assume not mentioning springs was an oversight when talking about valvetrain as they are definitely part of it and they are not referenced with a cam either.

 

However, like you say it is a double hit for those putting in a cam as unless you get radical it isn't necessary to change the rockers but springs are almost always required on a domestic V8. OHC motors with light little valves probably don't require them.

 

And pushrod length may have to be changed after a head shave for a rebuild on a stock motor....

 

Now, who is going to protest some PAC springs that look the same as stock or measure pushrods to see if they are .100 short? Good luck.

 

I see this as another example of import centric rules.

Edited by Bandit
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