HOME FORUM RULES CONTACT
     
   
   

Go Back   CLASS RACER FORUM > Class Racer Forums > Stock and Super Stock
Register Photo Gallery FAQ Community Calendar

Reply
 
Thread Tools Display Modes
Old 07-04-2010, 08:34 AM   #1
X-TECH MAN
Banned
 
Join Date: Dec 2007
Location: Lake Placid, Florida
Posts: 3,203
Likes: 1,047
Liked 235 Times in 110 Posts
Talking Re: Why did nhra change the cam and valve spring rule in 1985?

Quote:
Originally Posted by Billy Nees View Post
The trouble with setting a specific # for valve springs in this day and age is that the cam manufacturers are building cams that a flat tappet lifter just can't follow even with the best springs! I believe that some of the really sharp Stocker engine builders are actually getting away from "square" cams and going back to "softer" lobes at least on the exhaust as they're finding they're "cleaning up" the intake charge by not bouncing the exhaust valve around on the seat. Think about what the "harmonics" of that exhaust valve bouncing on the seat is doing to the intake charge not to mention the cylinder pressure.
Another good reason for "softening" the lobe is simply to use less spring. Heavy springs just "tie up" horsepower that can't be used to accelerate the vehicle.
I guess where I'm going with this is that as much as I'd like to see a "valve spring spec" rule put in the book it would make a lot of cams in use today unuseable and I don't forsee any of todays Stocker engine builders or cam manufacturers lobbying for a rule that will make their stuff unuseable.
But these are just the ramblings of a bored, crazy old fool living on a hill in Pennsylvania.
It might make some of the "square" cams unusable but a max spring pressure rule would put everyone in the same boat and keep more engines in one piece. Less chance for a broken bouncing valve destroying an engine and maybe less chance of being forced to run a diaper in the near future. Not only the "SQUARE" cams but what about some of the 55mm cams I have been hearing about in stock. I wouldnt think they would be legal but they are out there. Ramblings of an old retired foolish dumb tech guy living in the flat part of Florida.

Last edited by X-TECH MAN; 07-04-2010 at 08:40 AM.
X-TECH MAN is offline   Reply With Quote
Old 07-04-2010, 09:29 AM   #2
Bob Pagano
VIP Member
 
Bob Pagano's Avatar
 
Join Date: Jun 2002
Location: New Holland, PA Mooresville,NC
Posts: 1,163
Likes: 243
Liked 16 Times in 11 Posts
Talking Re: Why did nhra change the cam and valve spring rule in 1985?

Terry, You need something to do.......I know, you can join the hunt for the 25 foot python seen in your driveway last month. Billy Chupacabra was seen in the area of your Hilly home, be careful at nite they sniff out empty beer bottles left about.
__________________
Bob Pagano A/SA
Bob Pagano is offline   Reply With Quote
Old 07-04-2010, 09:51 AM   #3
X-TECH MAN
Banned
 
Join Date: Dec 2007
Location: Lake Placid, Florida
Posts: 3,203
Likes: 1,047
Liked 235 Times in 110 Posts
Talking Re: Why did nhra change the cam and valve spring rule in 1985?

Yeah...Im bored. I already shot a snake in my yard a couple of weeks ago.
X-TECH MAN is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 01:27 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright Class Racer.com. All Rights Reserved. Designated trademarks and brands are the property of their respective owners.