I am not an engine guru so i have a simple curiosity question. I have a 455 with Rhoads lifters. Is there any specific oil that enhances the lifter operation so as to keep them a bit quieter at idle? I surmise that any quality oil will work as advertised but just have to ask? The engine was rebuilt by a previous owner and it is a block from an 88 or 98 low compression engine bored 30 over. they put a higher lift cam and used Rhoads lifters to increase vacuum to facilitate the power steering, brakes etc. at idle. The lifters are a bit noisy at idle and I've been told this is normal as it dissipates at increased RPM. Just curious if this is normal or do i have an impending issue. The car is not a racer but a driver. 70 442 4speed convertible.

 

I am by no means an engine guru but I ran the Rhoads V-Max Lifters for about 20,000 street miles on a 455 with a relatively large cam (JM 5-6). I got an extra 3" of desperately needed vacuum and improved idle and had better low rpm cruising around town. The noise they make is the sound of valves closing slightly quicker than normal on the trip down the back side of the cam lobe. If my math is right you are hearing about 100 clicks per second at idle which sounds a bit like a sewing machine or a bee swarm, and that noise is normal for the Rhoads. The working principle is that the metered oil passage in the valve is sized up so as to bleed off enough of the oil inside the lifter to drop the pushrod and valve faster than normal. At high rpm there is not enough time per rotation to bleed off the extra oil and drop the valve quicker. When rpm drops to about 3000 the early valve closing effect begins and it is all-in by idle speeds, where you get the maximum cam shrink effect. If you mess with oil viscosity to make them quiet, you are reducing the effect they have on "shrinking the cam" and you will loose some of the benefit of increased idle vacuum and smoother low rpm operation. The Rhoads lifters are a relatively low cost option to tame a "too big for the application" cam and boost idle vacuum. If the lifter noise is bothersome the ultimate solution is to replace your cam with something more street friendly with less duration.

 

Rhodes lifters work by bleeding down the lifter internal pressure at low speeds, which reduces the lift and effective duration of the cam for better low speed manners but results in excessive valvetrain lash. That is the source of the noise. Using a thicker oil to mask the noise also defeats the purpose of the lifters, as the thicker oil prevents them from bleeding down. I've always felt this was kind of a half-fast solution to using too big of a cam.

 

Here's a good FYI on Rhoads lifters

https://rhoadslifters.com/Pages/FAQs.html

 

Rhodes lifters was another "new" technology discovery back in the day. "Varicam" was another device that really never worked or took off in general use. The sales literature painted a pretty picture. Neither Rhodes lifters or Varicam ever took off.
https://www.jalopyjournal.com/forum/....629885/page-2

 

^^^^^^

 

They should update their FAQ, since Rhodes lifters have been around since at least the 1980s...

 

I see where he was done "inventing" in 1974. I remember all the ballyhoo introduction in car magazines which must have been in the 1960's. Back then, you had three cam choices......Stock, 3/4 Race, and Full race.

James E. Rhoads1913-1974

My Father, James E. Rhoads supported his wife and five sons by laying and finishing hardwood floors. He was, however, an inventor at heart with a strong interest in improving the performance of automotive engines.Dad set his mind to work and developed what has proven to be one of the most advanced performance products on the market...The Rhoads Variable Duration Lifter. It's been years now since my father went to be with his Father in heaven and Dad, if you can hear me you've got a lot of satisfied customers who would gladly tell you just how great your lifters truly are. ---Jack Rhoads

 

Gentleman Thank all of you for your inputs and answers. It was as I expected and will continue to use the oil my tech uses. VAV 10w30.

 

My fried had a 455 w/ Rhodes lifters- sounded like crap and he took a lot of crap from people about it, Poor guy- he put a lot of money in that car and it was slow as hell off line- looking back now I realize why... 455 w/ big cam and 2.56 rear w stock converter....

 

what type of valve covers do you have on it? aluminum covers are quieter than factory type.

heavier viscosity does quiet them a bit. aggressive ramps really hammer the lifter , so the Rhoads will be even noisier with that type of cam… what cam is in it?
they were designed for old school style big duration slow ramps like the 328 W30 cam..

it won’t hurt to try 20W50 for one oil change. I know it’s made a difference when I go from 10 30 break in oil to 20 50

 

thicker oil doesn’t prevent them from bleeding down, it slows the bleed down rate which does quiet them some.

the whole point of the lifter is to allow the use of a bigger cam. it increases idle vac and very low end TQ. or, tame a big cam already installed

 

I guess Rhoads lifters would give a radical cam better street manners. No need for vacuum boost brakes at the track. That varicam system is still a mystery. Manufacturers have used VVT for years now.