what chromolly push rods? |
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what chromolly push rods? |
shaggy |
Oct 10 2006, 12:50 PM
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#1
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mechanic/welder/fabricator Group: Members Posts: 702 Joined: 26-September 05 From: Gilbert, AZ Member No.: 4,869 Region Association: None |
im changing to chromolly push rods to do rocker arm geometry
i noticed on the aircooled site they offer several different ones. what ones do i want: what diameter? with or without taper? thanks -jim |
Twystd1 |
Oct 10 2006, 01:50 PM
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#2
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You don't want to know... really..... Group: Members Posts: 2,514 Joined: 12-September 04 From: Newport Beach, California Member No.: 2,743 |
stock cam or big lift cam.
twystd1 |
Aaron Cox |
Oct 10 2006, 01:56 PM
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#3
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
i went with manton chrome-moly's and i think they were 3/8
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Jake Raby |
Oct 10 2006, 02:11 PM
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#4
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Pushrods
When you lose a tip from one of the imitation pushrods you'll see why these are all we use.. I have used thousands and never had a bad one, I have bent TWO of them in the past 8 years... |
Chris Pincetich |
Oct 10 2006, 02:53 PM
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#5
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B-) Group: Members Posts: 2,082 Joined: 3-October 05 From: Point Reyes Station, CA Member No.: 4,907 Region Association: Northern California |
Jim - DID YOU LISTEN TO THE IV DIMENSION radio show? Oct 6 was valve train. That's all I can say...be an INFORMED buyer (IMG:style_emoticons/default/biggrin.gif)
(IMG:style_emoticons/default/beerchug.gif) |
thomasotten |
Oct 10 2006, 03:00 PM
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#6
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Senior Member Group: Members Posts: 1,545 Joined: 16-November 03 From: San Antonio, Texas Member No.: 1,349 |
So with these, you get the car hot, then adjust? How about the first time you are installing, how do you adjust the clearance?
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bd1308 |
Oct 10 2006, 03:02 PM
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#7
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
zero lash, you want the push rod to move by some method and thats it.
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Aaron Cox |
Oct 10 2006, 03:14 PM
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#8
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
nope. when dead cold.. you set it to ZERO lash....
steel doesnt expand as much as aluminum.... so when the motor is nice and hot, and the aluminum expanded... and the steel pushrods havent, you have a few thou of lash when hot.... just right... |
Jake Raby |
Oct 10 2006, 03:28 PM
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#9
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Jim - DID YOU LISTEN TO THE IV DIMENSION radio show? Oct 6 was valve train. That's all I can say...be an INFORMED buyer (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/beerchug.gif) yep- thats the best 1:22 minutes you can spend! |
blitZ |
Oct 10 2006, 04:17 PM
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#10
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Beer please... Group: Members Posts: 2,223 Joined: 31-August 05 From: Lawrenceville, GA Member No.: 4,719 Region Association: South East States |
So, when you adjust your valves with these pushrods, you use zero clearance intake and exhaust? Excuse me, I'm a little slow.
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Aaron Cox |
Oct 10 2006, 04:30 PM
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#11
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
So, when you adjust your valves with these pushrods, you use zero clearance intake and exhaust? Excuse me, I'm a little slow. YEP. with mantons and a header, i did a valve adjust in 7-8 minutes (IMG:style_emoticons/default/smile.gif) |
blitZ |
Oct 10 2006, 05:37 PM
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#12
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Beer please... Group: Members Posts: 2,223 Joined: 31-August 05 From: Lawrenceville, GA Member No.: 4,719 Region Association: South East States |
So, when you adjust your valves with these pushrods, you use zero clearance intake and exhaust? Excuse me, I'm a little slow. YEP. with mantons and a header, i did a valve adjust in 7-8 minutes (IMG:style_emoticons/default/smile.gif) Great, guess I'll have to get a new feeler gauge. Mine doesn't have a zero. |
Joe Ricard |
Oct 10 2006, 05:51 PM
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#13
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
So, when you adjust your valves with these pushrods, you use zero clearance intake and exhaust? Excuse me, I'm a little slow. YEP. with mantons and a header, i did a valve adjust in 7-8 minutes (IMG:style_emoticons/default/smile.gif) Great, guess I'll have to get a new feeler gauge. Mine doesn't have a zero. That's pretty funny. mine does. (IMG:style_emoticons/default/poke.gif) Actually zero lash is a bit of a misnomer. More accuratley for the "slow kids" no perceptable slop when moving rocker are against valve and push rod. BUT you can still rotate the push rod with your finger tips. OK that is zero lash but also how you achieve it. |
thomasotten |
Oct 10 2006, 08:55 PM
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#14
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Senior Member Group: Members Posts: 1,545 Joined: 16-November 03 From: San Antonio, Texas Member No.: 1,349 |
Ok, so let's say you install these, and then you sell the car. The new owner, not knowing anything about them takes them to the local "vw" shop. They adjust the valves using the old method, with a feeler guage, when cold. Won't the engine run like crap for that person? Would they ever figure out that these aren't normal push rods?
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Aaron Cox |
Oct 10 2006, 09:13 PM
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#15
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
Ok, so let's say you install these, and then you sell the car. The new owner, not knowing anything about them takes them to the local "vw" shop. They adjust the valves using the old method, with a feeler guage, when cold. Won't the engine run like crap for that person? Would they ever figure out that these aren't normal push rods? or you could disclose the fact when selling (IMG:style_emoticons/default/poke.gif) who cares what the NO does? lol yep, their engine would clack all over the place and have like 9-10 tho clearances LOL |
anthony |
Oct 10 2006, 09:24 PM
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#16
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2270 club Group: Benefactors Posts: 3,107 Joined: 1-February 03 From: SF Bay Area, CA Member No.: 218 |
I'm guessing that at least it wouldn't damage the engine.
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thomasotten |
Oct 11 2006, 07:31 AM
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#17
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Senior Member Group: Members Posts: 1,545 Joined: 16-November 03 From: San Antonio, Texas Member No.: 1,349 |
Perhaps someone could design a warning sticker that goes on the valve covers. WARNING! - ACHTUNG!
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Jake Raby |
Oct 11 2006, 07:35 AM
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#18
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
I have those stickers for my engines..
Many people still stuck in the 70s run their lash at stock settings even with these pushrods.. Its just loud and loses about .050 of the valve lift to lash and takes some valve duration away... Not optimum.. |
Matt Romanowski |
Oct 11 2006, 07:45 AM
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#19
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Senior Member Group: Members Posts: 878 Joined: 4-January 04 From: Manchester, NH Member No.: 1,507 |
What I would be more concerned about is the fact that you get .004-.008 lash (from Jake's page). That seems like a pretty big variable. Granted, I've never checked Al. ones when hot to see the difference.
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Jake Raby |
Oct 11 2006, 08:44 AM
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#20
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
The difference is the same with stock..
be more concerned when the engine runs over temp and the lash completely closes- when that happens valves burn, seats drop and even the heads of valve weaken and snap off... Excess lash loses power and is loud, but it'll never compromise your engine. Not enough lash will open the wallet fast. chromoly pushrods could be considered an insurance policy, when you over temp the lash opens up.... |
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