Tons of /4 rocker arm Questions......, stock /4 ratio, variance between sets... |
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Tons of /4 rocker arm Questions......, stock /4 ratio, variance between sets... |
Mueller |
Sep 30 2003, 09:37 AM
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#1
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
I was going to use the Pauter roller rocker arms
(ratio of 1.5:1) but decided to sell them since the money in my pocket would be better right now than the money in my motor (IMG:style_emoticons/default/smile.gif) 1)I thought I read that the stock /4 arm are supposed to be 1.3:1..is this correct? 2)How often are they the correct ratio? 3)What is the biggest difference has anyone seen? 4)Would the /4 benifit from using different ratio arms on the intake and exhaust (example: stock ratio on intake, 1.5 ratio on exhaust)? 5)What improvements can be made to the stock arms? 6)Is there an interest in modified/blueprinted stock arms? 7)Is there an interest in non-stock ratio stock type arms? 8)Pauter already offers 1.5:1 aluminum arms, but is there a market for different ratio aluminum arms? |
Charles Deutsch |
Sep 30 2003, 10:07 AM
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#2
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Unregistered |
DD has said in the past that he read somewhere that the rocker arm ratio was 1.3:1. Couldn't this be measured directly on the stock arm? Where did you buy the Pauter roller rocker arms? Is there a place on the web that sells them?
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Charles Deutsch |
Sep 30 2003, 10:15 AM
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#3
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Unregistered |
I just visited the Pauter web site and realized that they already do something that I thought would be a good idea for an aircooled flat-four motor : "... tremendously strong foundation provided by the one-piece block ".
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Mark Henry |
Sep 30 2003, 10:41 AM
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#4
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
1/ 1.3:1
3/ VW was good at getting the ratio correct 4/ 2 different ratio's would need a custom cam, not worth it IMHO. 5/ You can lighten them a bit and if your anal you can balance them all the same. 6/ little, see above 7&8/ you must have cams made for different ratio's, forged Cr-Mo would be much better, I'm not crazy about aluminum rockers and rollers have the heavy part right where you don't want it, over the valve. |
Mark Henry |
Sep 30 2003, 10:45 AM
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#5
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
QUOTE(Charles Deutsch @ Sep 30 2003, 08:15 AM) I just visited the Pauter web site and realized that they already do something that I thought would be a good idea for an aircooled flat-four motor : "... tremendously strong foundation provided by the one-piece block ". Pauter big block is for drag racing only. |
john rogers |
Sep 30 2003, 11:17 AM
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#6
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Senior Member Group: Members Posts: 1,525 Joined: 4-March 03 From: Chula Vista CA Member No.: 391 |
Hopefully this will help some:
1)I thought I read that the stock /4 arm are supposed to be 1.3:1..is this correct? - Yes they are 2)How often are they the correct ratio? - Pretty close most all the time 3)What is the biggest difference has anyone seen? - We have checked probably 2 dozen and they were right on. 4)Would the /4 benifit from using different ratio arms on the intake and exhaust (example: stock ratio on intake, 1.5 ratio on exhaust)? - A different cam ggrind would be needed 5)What improvements can be made to the stock arms? - Use 911 or Pinto adjusters 6)Is there an interest in modified/blueprinted stock arms? - Hummm, probably not much 7)Is there an interest in non-stock ratio stock type arms? - Humm probably not 8)Pauter already offers 1.5:1 aluminum arms, but is there a market for different ratio aluminum arms? - Pauter's are 1.48:1 and are generally used with a cam that has a much smaller base circle and the gring made to reduce the ramp up when the lifter starts up the lobe so the load on the valve train is slightly less. The cam has to ground to use these or there will be interference problems with the pistons. We used them in my stroker four and even switached back to stock rockers for a while and figured we lost 20 to 25HP as the total lift of the cam was reduced. The engine was less responsive too. Pauter and Auto craft are about the only ones doing this stiff and usually it is for drag motors or low RPM off road engines. |
Charles Deutsch |
Sep 30 2003, 12:58 PM
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#7
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Unregistered |
QUOTE(Mark Henry @ Sep 30 2003, 08:45 AM) QUOTE(Charles Deutsch @ Sep 30 2003, 08:15 AM) I just visited the Pauter web site and realized that they already do something that I thought would be a good idea for an aircooled flat-four motor : "... tremendously strong foundation provided by the one-piece block ". Pauter big block is for drag racing only. Yes, I know. It's just that with the reciprocating mass of the pistons, I feel that the crank should be anchored in a solid mass rather than a bolted-together case. Just a feeling I got everytime I thought about it ... obviously, I have no hard numbers. |
redshift |
Sep 30 2003, 01:12 PM
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#8
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Bless the Hell out of you! Group: Members Posts: 10,926 Joined: 29-June 03 Member No.: 869 |
QUOTE(Charles Deutsch @ Sep 30 2003, 12:15 PM) I just visited the Pauter web site and realized that they already do something that I thought would be a good idea for an aircooled flat-four motor : "... tremendously strong foundation provided by the one-piece block ". But unstreetable. (IMG:style_emoticons/default/sad.gif) M |
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