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Old 07-25-2022, 10:04 AM
BILL BOWMAN1's Avatar
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Default Wideport lifter options

Iíll get right to the point, are solid offset roller lifters the only way to go? I am returning my car to the street and would like to run a Mechanical Flat Tappet cam, and use my heads. I am assuming the pushrod angle will be too strong without the offset lifter.

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Old 07-25-2022, 07:55 PM
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I haven't tried it but if there is enough clearance for the pushrod in the heads it should be OK. BBC have crazy angles on their pushrods from the factory.

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Old 07-25-2022, 08:09 PM
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How much offset are your rocker arms currently?

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Old 07-25-2022, 09:28 PM
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I donít have the part number on the shafts, but center of valve to center of pushrod is roughly .400.
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Old 07-26-2022, 02:35 AM
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Have you thought about going with a mild SR cam and running a lifter like the BAM with DLC option ? The Drag Week guys love them and you would think they would last a long time with less spring pressure. No needle bearings to worry about.
And you could still use your Crower Enduras you paid good money for.
Win-win.

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Old 07-26-2022, 08:57 AM
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Yes that was my original plan, changed my mind several times since. Probably will go that direction.

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Old 07-26-2022, 09:14 AM
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You'll lose about .075-.080 of pushrod clearance half way up the pushrod, which is roughly the bottom of the head, so if you have the room there it shouldn't be an issue

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Old 07-26-2022, 09:37 AM
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And if I go down to a 5/16 pushrod, that will give me another .060 to play with. Who know it may just work, but there is only one way to know for sure, yank the intake and try it. Thanks for the input!

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Old 07-26-2022, 09:59 AM
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I think you will be okay. Fwiw, unless you already have the parts, FT Pontiac cam cores are hard to find and some of them are of questionable quality. There are not any quality SFT lifters currently available. IMO you might want to consider sticking with your current lifters (assuming you feel they are without issue) , reprofile or replace your cam with gentler lobes and soften up your valve springs some.

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Old 07-26-2022, 11:26 AM
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"...reprofile or replace your cam with gentler lobes and soften up your valve springs some."

My application is currently street only but that's what I ended up doing about two years ago after a roller lifter failure. At the time I was running a aggressive UltraDyne MSP roller with 0.709" lift in conjunction with PAC 1243 springs rated 240 on the seat.

The new cams intake lobe we used had the same .050" duration but less aggress, or less intensity, depending on the wording. I worked with Tim at Bullet Racing Cams and with that lobe he said years ago they used to run it with a typical Small Block Chevy valvetrain mass with around 190 lbs seat pressure, and in a Big Block Chevy mass at around 220 pounds if memory serves me right. Tim suggested in a Pontiac at the 190 lbs. But keep in mind these numbers were from 30+ years ago and I don't know what type parts were used.

I choose a spring rated 220 lbs at 1.900, knowing it will lose pressure after run in. That and my intake valves are a larger 2.150" diameter and with a longer stem length for that 1.900" installed height. It tested 205-210 lbs after the dyno session with my LSM on the head spring tester.

.

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