I have them in a amll block mopar. they are kinda noisy. like a solid or even a collpased lifter. I have 23 inches of va*** in the motor at ideal and I think they work great. like I siad just a little lifter noise. I think I run a .441 lift cam and I beileve the claim it takes out .02 of lift before the lifters pump up
Don't plan on getting any advertised RPM out of your camshaft with the Rhoads lifters. Or at least, thats what happened with 2 sets of them in my Pontiacs! I changed out to stock TRW and gained a ton of top end power.
As much trouble as folks are having with todays oils and flat tappet high lift cams, I don't see the wisdom of intentionally adding slop to the valvetrain...
I got a set of the Pro Magnums from Comp, basicly the same thing. They are noisy SOB's! I just got what they told me to get for my turbo cam in the Camaro. I have a buddy that works there and got me the stuff at a good price. I don't know if there is a real benifit though.
I've had them in my sbc with a Crane cam for about 16 years. Decent vacuum, no problems. Yes they are noisy, so what, its a hot rod for cryin out loud.
They do make a difference in low end torque and if you need extra vacuum at idle they are the way to go.
I've done alot of research on Rhoades Lifters, and have decided to use them. That being said, here is what I have learned: 1. The lifters themselves are not "noisy". As you may know they are manufactured with an oil relief slot inside the bore that, when the engine is operating a low rpm, allows the lifter cup to "sink" into the lifter bore. Obviously, on the opening ramp of the cam, the valvetrain is working against the spring, but on the closing ramp, the spring is controlling the valvetrain motion...and with a relatively "relaxed" lifter, the spring closes the valve very rapidly, so what you are hearing is the valve closing. 2. The cam/lifter break in issues do***ented lately all seem to come to the same conclusion..."junk" lifters and incorrect break in procedures. Apparently, there were/are only a few lifter manufacurers, and lots of that manufacturing had moved offshore. Anyway, I am fairly certain that Rhoades are made in the US, and therefore fairly certain about the integrity of their metallurgy and tolerances. Certain enough to try them, anyway. As I understand it, every Viper has Rhoades Lifters, so that is some sort of endor*****t. 3. Again, regarding cam/lifter break in failures, aside from the poor lifter quality...modern oils are an issue. I am no petroleum chemist, but I understand that the basic issue is the removal of high pressure metal-to-metal intersection lubrication additives, especially zinc. Granted, typical off-t******lf automtive oils have had those additives removed, but there are options. Diesel oils, "boutique" racing oils, and various supplements. GM makes a great additive called EOS, and they also sell and a Cam and Lifter Break In additive that lots of folks use as an "every oil change" additive. In fact, I have always broken in my engines with Rotella and a quart of EOS, and never had a problem. So, yeah...I overcammed and over-manifolded and over headered my motor In terms of low rpm where I need vacuum) and wanted a solid lifter sound without having to adjust the valves frequently. So I am gonna give 'em a go
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