RB and a roller Cam

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tooslow

tooslow

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I wanted to run a Roller Cam at one time but settled with a Mech flat tappet cam. I Drive my cars all over and sometimes 200 miles a weekend

I did alot of reading on running a roller cam in a 440 block and my conclusion was: (Hyd roller because of less spring pres reqiured)

An RB block does not have adequate oiling for the rollers for a car that will be driven for a number of miles. especially if you will be ideling here and there?
If you are going to run a Roller to do it right you need to make some extensive modifications to the oiling system(add an external passage , lines, ect...) Sure its easy to install a Roller Cam but it may come apart and there goes your motor due to the oiling deficencies????

I have a CHevy friends with 454's and they pretty much just pop in there Hyd roller cams and put 40K on the motor-(jeolous:hmph:)
Sure I am, I am running stone age Purple Sticks(safe)
On the otherhand an RB has a LARGE diameter lifter bore so its easy to run more agressive ramp rates with a Mech-less stuff to brake!!?

Please Comment
 
If you are rebuilding the engine, another few changes while it's apart is no big deal.

If you are only expecting to perform a cam swap and have everything just work out, calling someone like Hughes Engines might be a good option.

I know a couple of guys whom have purchased valve train items from them, they definitely have Mopar B/RB down to a science. This is where my roller valve train will be coming from.
 
First, you have to seperate hydraulic rollers from solid rollers. Solid rollers need more prep to be safely run on the street. Hydarulic rollers are simply a hydraulic lifter with a wheel on the bottom. They are heavier, and while they rewuire no real modifications, IMO, they are not worth the money. Because they can't have a rate of lift as fast as a .904 sized solid flat tappet. So you've got a larger price tag, need a heavier valve spring, and can't move the valve any faster or better than a flat tappet. The only reason IMO to run one, is to steer clear of needing to run the high zink oils or additives and avoid the breakin procedures. If you want a solid roller on the street, again, IMO, the block needs lifter bore bushings, and the cam needs to be carefully chosen bearing in mind idle time, valve spring life, and roller lifter life.
 
moper said:
First, you have to seperate hydraulic rollers from solid rollers. Solid rollers need more prep to be safely run on the street. Hydarulic rollers are simply a hydraulic lifter with a wheel on the bottom. They are heavier, and while they rewuire no real modifications, IMO, they are not worth the money. Because they can't have a rate of lift as fast as a .904 sized solid flat tappet. So you've got a larger price tag, need a heavier valve spring, and can't move the valve any faster or better than a flat tappet. The only reason IMO to run one, is to steer clear of needing to run the high zink oils or additives and avoid the breakin procedures. If you want a solid roller on the street, again, IMO, the block needs lifter bore bushings, and the cam needs to be carefully chosen bearing in mind idle time, valve spring life, and roller lifter life.
Click to expand...
Thanks,
Kind of what i have read. More stuff to break? Dont like alot of idling
Hughes sells a nice Mech 248 dur 575 flat tappet cam for 175.00 plus 160 for lifters. Heck with the fancy I am going with the inexpensive and EASY
THANKS GUY's!!!
 
moper said:
First, you have to seperate hydraulic rollers from solid rollers. Solid rollers need more prep to be safely run on the street. Hydarulic rollers are simply a hydraulic lifter with a wheel on the bottom. They are heavier, and while they rewuire no real modifications, IMO, they are not worth the money. Because they can't have a rate of lift as fast as a .904 sized solid flat tappet. So you've got a larger price tag, need a heavier valve spring, and can't move the valve any faster or better than a flat tappet. The only reason IMO to run one, is to steer clear of needing to run the high zink oils or additives and avoid the breakin procedures. If you want a solid roller on the street, again, IMO, the block needs lifter bore bushings, and the cam needs to be carefully chosen bearing in mind idle time, valve spring life, and roller lifter life.
Click to expand...


Depends how big the cam is . I run a .550 crower solid roller in my 70 440-6 Charger and drove it to work every day for over a year . No Issues . Idles great . runs 12.30's through 3.55's even though it's 4000 lbs.

What you said about the hydraulic rollers is food for thought . I had never considered this aspect and may reconsider any urge I might have to run one in the mild 360 I'm building .
 
my 440 is being built as we speak and I am using a hyd roller for a few reasons.

1. Don't need oil additive that the older cams need now.

2. Rollers offer a better cam profile and increase throttle repsonse

3. No break in period required

Downside is yes they are more expensive and you need a bronze cam gear.
 
Back in the day I use to put Engles RK 48 in 440's for customers as a first step into roller cams on the street "I must have put in 30-40 RK 48's"...Nothing done to the block as far as oil mods go...Guys would put 5000 miles a summer on their cars no problem...
In the spring I would set the lash and check the oil pump drive for them and away they would go for another summer.
The only thing I would stress to them was to run an oil additive like KleenFlow's 205 or Wynn's 50 or 80 plus and keep the oil CLEAN..!!
You can't be making 550-600 hp with a 440 and go a 1000 miles between oil changes on the street and not expect to have to change the bronze oil pump drive gear...
 
I am not into roller cams for 440s yet.When I serched out a cam for my cuda I went with a hyd flat tappet.Can,t wait to test it. This is the specs. Camshaft Technical Details
Intake Valve Lift 1.5
Exhaust Valve Lift 1.5.576"
.593"
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Intake Valve Lift 1.6
Exhaust Valve Lift 1.6.614"
.632"
x.gif
Intake Duration at .050"
Exhaust Duration at .050"250°
255°
x.gif
Lobe Separation Angle108º
x.gif
Intake Opening at .050"
Exhaust Opening at .050"20° BTC
58.5° BBC
x.gif
Intake Closing at .050"
Exhaust Closing at .050"50° ABC
16.5° ATC
x.gif
Min. Suggested Cylinder PSI200
x.gif
Sweet Spot RPM2800 - 6000
 
That's why I said a roller on the street has to be carefully chosen. They can last. But also like I said, the lifters should be rebuilt on a regular basis (every two years) and the springs should be either replaced or checked yearly. It's only my opinion but not doing lifter bore bushings for ANY solid roller (big or small block) is a cheap risk I won't take. I've personally seen three complete engine failures that were the result of a lifter coming out of the bore and the oil pressure falling before the engine could be shut down. For $500, risking an $8K or $12K engine by avoiding that process (and avoiding the power) does not make sense to me.
 
I had a brand new herbert roller and sold it before i put it
In due to the cost. Glad i did. There are tooo many fast guys
Running solid flat tappets and doing it cheap! Those purple
Cams work! Theres somthing to say about 30yrold tech
 
Top Heavy said:
If you are rebuilding the engine, another few changes while it's apart is no big deal.

If you are only expecting to perform a cam swap and have everything just work out, calling someone like Hughes Engines might be a good option.

I know a couple of guys whom have purchased valve train items from them, they definitely have Mopar B/RB down to a science. This is where my roller valve train will be coming from.
Click to expand...

I agree with Hughes, I ran several of there flat tappet cams over the years. The last one was a HEL 7680 with 1.6 rockers in a 446 Scamp that worked real good. Ran 6.35-6.40's.
 
I understand that you can order a billet roller now with a cast iron
distributor gear pressed on - no need to run a bronze gear and no
more gear wear.

That said, I'd like to hear more about running a nice solid flat-tappet
cam with the Shubeck lifters. I've heard good and bad.
 
What off the shelf oil is recommended for flat tappet cams? After proper cam breakin can I use regular oil, or does it have to be the special zinc type? I was thinking rotella 15-40. But I have no clue. I'm in the process of building a 451 non-roller (due to the extra cost vs hp/ tq). ](*,)
 
You have to run iols that are formulated for the flat tappet stuff. They are "shelf" part numbers, but not stocked by normal retailers. Joe Gibbs and Valvoline Not For Street Use VR-1 are what I recommend when I use an aggressive flat tappet. While I don;t agree that 30yr old tech is the way to go, flat tappets definately are with proper care in assembly and break in.
 
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