Roller lifters, Anyone tried them? |
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Roller lifters, Anyone tried them? |
r_towle |
Oct 26 2015, 09:31 PM
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#1
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Custom Member Group: Members Posts: 24,597 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Has anyone tried roller lifters in a type 4, or any flat motor?
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Jake Raby |
Oct 28 2015, 12:11 PM
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#2
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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 problems you will have will be with properly centering the lifters to be perpendicular to the cam. Most T4 cases are NOT properly centered with their original lifters. Bushing must be bored for proper alignment, and a special jig is used to align these from the camshaft centerline.
Once you overcome this, the next challenge is properly locking the lifters so you won't experience "cam walk", which occurs when the lifters travel up one side of the lobe, and down the other. What you will find is the factory thrust control deck is not large enough to control this. This holds true, even if you use the 993 layshaft thrust bearings for the job. I tried factory Ford, Chevy and Mopar lifters. I then tried .742" Harley lifters, before I realized that I simply needed to man up and manufacture a lifter that was the proper diameter, and had an optimum wheel diameter. I spent two years fooling with it, and solved all the problems in just two months when using a proper lifter. Making this work was one challenge. Making it live was another, and neither was cheap, or easy. The gains in torque can be HUGE as you can lift up to .010" per crank degree after 8*ATDC, which is extreme compared to any flat tappet. It is HELL on rocker arms, and I broke 3 Pauter rockers in 4 months before I went back to stock on my wife's car. Other than the rockers, that engine has been flawless for the past 7 years, and 40,000 miles. She and I, drove it 14,000 miles in just one year in 2010. It has flat torque from 1500-6K, and is unreal to drive. The oil samples I gain from this engine are better than any other T4 I have ever evaluated, and this holds true with all roller lifter engines I have built. As far as ceramic lifters go, yes, they are indestructible, and I still have a few seats on my shelf for my own cars. They look perfect after 15 years in a few of my engines that have come back for service. I first used them in 1999, and have NEVER had one fail. This post has been edited by Jake Raby: Oct 28 2015, 12:15 PM |
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