Valvetrain Confusion, Why not rollers |
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Valvetrain Confusion, Why not rollers |
Teknon |
Jan 5 2005, 04:18 PM
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#1
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The more I learn the dumber i think I am Group: Members Posts: 357 Joined: 10-August 04 From: Denver, Colorado Member No.: 2,505 Region Association: Rocky Mountains |
I'm having the hardest time deciding on a cam a valve train. Have 3 emails and a phone call into Pauter for there roller rockers. They must not need customers. Looked at Scats. I also like the hydraulic idea. Just too much info to wade through.. What did you engine builder decide on and why?
(IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/barf.gif) |
lapuwali |
Jan 5 2005, 04:22 PM
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#2
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
If shoptalkforums was working, I'd suggest going over there and reading some long threads Jake created on the subject. He's got some ceramic lifters that appear to last forever. He's also working on some roller units. Lifters for the Type IV are apparently subject to quite of bit of dodgey QA, and there's a lot of junk available right now.
I believe Jake can supply both a cam and matching lifters for nearly any application you've got, so perhaps you should try contacting him (www.aircooledtechnology.com). |
lapuwali |
Jan 5 2005, 04:25 PM
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#3
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Well, shoptalkforums is working again, so go and dig around there in the AircooledTechnology forum.
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Teknon |
Jan 5 2005, 04:28 PM
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#4
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The more I learn the dumber i think I am Group: Members Posts: 357 Joined: 10-August 04 From: Denver, Colorado Member No.: 2,505 Region Association: Rocky Mountains |
Gotta get on the shop forum thing. Wish Jake just had prices posted on things. (IMG:http://www.914world.com/bbs2/html/emoticons/chairfall.gif)
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Mueller |
Jan 5 2005, 04:31 PM
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#5
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
it seems pretty much everything from Pauter is "race" only and not the best for street applications.....I had a set of their roller rocker arms that I got rid of due to them needing special oil routing...the guy that bought them is now dealing with the extra plumbing (IMG:http://www.914world.com/bbs2/html/emoticons/smash.gif)
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Mueller |
Jan 5 2005, 04:32 PM
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#6
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
in a few weeks (I hope that soon), you'll be able to click away on his site until your Visa/MasterCard explodes (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif) |
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Dave_Darling |
Jan 5 2005, 05:30 PM
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#7
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
The currently-available roller rocker arms are not "self oiling". They are fine for short duration (e.g., 1 season of drag racing), but on the street they stand a decent chance of wearing very quickly. Unless you figure out a way to get oil onto them, and in particular onto the correct bits of them.
Stock rocker arms are self-oiling; they get their oil through the pushrods and it travels through passages inside the rocker arm to the pivots and possibly up to the upper end of the rocker arm? I may be wrong about the last bit. It would be neat to have roller rockers that are actually self-oiling, but designing and building such is waaaaaaay beyond anything I can wrap my brain around. --DD |
lapuwali |
Jan 5 2005, 05:48 PM
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#8
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Shows I didn't really read the post, either. I'm talking about lifters and you're talking rockers...
Roller rockers on other engines I've seen were oiled by splash. The ones commonly used on A-series engines (British stuff), for example, use rolling element bearings for the rollers, which typically don't require much oil, so splash is sufficient. Probably a completely different story on the Type IV. One of the downsides of rollers is they're a lot heavier, so valvetrain inertia comes into play. There's more to break. There are enough really high rpm engines out there that don't use rollers that I'd doubt their benefit except in really extreme conditions. |
Elliot_Cannon |
Jan 5 2005, 08:02 PM
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#9
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Senior Member Group: Retired Members Posts: 1,922 Joined: 26-March 03 From: Orange County Ca Member No.: 480 Region Association: None |
Go with the ceramic lifters. I had a 2.2 built by FAT Performance a few years ago. Had it in the car 20 miles and the lifters went bad. Pulled the engine out and took it back and they redid it with " the best lifters you can buy". Now a valve adjustment lasts about 400 miles and they start rattling and tapping again. Last time I checked them the #1 and 2 exhaust valves measured .011. This is a $6000 engine! Go with the ceramic lifters.
Cheers, Elliot |
Type 4 |
Jan 5 2005, 11:53 PM
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#10
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Member Group: Members Posts: 412 Joined: 30-September 04 From: Costa Mesa Calif. Member No.: 2,866 |
http://schubeckracing.com/new2/index.php?m..._position=53:53
These are the guys that make the ceramic lifters they also have the roller lifters. |
Jake Raby |
Jan 6 2005, 12:06 AM
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#11
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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 havetwo roller test engines on the road as we speak.. They don't use Schubeck components, but rather some pieces that can be seen here www.aircooledtechnology.com/research
These lifters are a patented design that does not need a key way, or guide at all to keep them running true with the cam lobe. They are working excellent and drop right in the stock case! We are still trying to perfect the ultimate camshafts to use with them, as these first engines used a flat tappet grind with a tad faster ramp to for ease and test purposes. At 5,000 miles I will tear into the engines and look for wear and then apply a cam with a much faster opening event to help with cylinder filling, thus adding power and efficiency. The grind I am working with now is based from a 5.0 Mustang master, and is very promising and suprisingly easy on the rest of the valve train. With a +5 on the exhaust side it show plug right in and perform well. Take the roller rockers and throw them in the trash. They are inferior compared to the stocker that VW gave us. I have NEVER seen a stock rocker break, but I can't say that for the rollers! The rollers are not compatible with 95% of the cams on the market (incorrect ramp rates that cause excess valve velocity and break parts on a daily basis) HELL, not even Pauter can sell you a cam that is within the acceptable limits of safety running those rockers! As for me and parts....... and prices... And descriptions... And compatibility.... Be ready for a mind blowing experience- Coming soon! (If I live through the opening stages of it) |
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