MM Roller Cams???

[BillyGman]

Hey, what do you guys think about the possibility of installing roller camshafts in the Marauder? I'm not sure if anyone makes them for this engine. I would think so since the Cobra has had this engine for a few years now. Right? Somebody borrowed my Comp Cams catalogue, so I can't look to see if they offer them for this motor right now. But I just wanted some feedback from you guys about this idea.......

[engine23ccvfd]

well considering I dont know what a roller cam shaft is and do not have the current roller catalog...unless its the one with all the push-up bras...no wait thats Sears......Just kidding! I have no idea but its a good question

[Murader03]

Funny you should ask. I just read an article in one of the Mustang rags about doing just that with the Cobra engine. I'll gather the article tonight at work and publish some of the particulars and possibly the company name if Logan don't kill it. Stay tuned...they made some impressive gains.....

[89lxbill]

The cams in a Marauder are already roller. That article you are referring to is installing solid roller lifters in a motor. What they don't tell you is that you have to periodically adjust the lash adjusters. No good for daily street use.

[Wags]

89lxbill is correct. And our motor is not the Cobra motor. The Cobra is an iron block with alum. heads, with more aggressive cam lobes. It also has a roots style blower (8lbs. of boost), for a rating of 390hp. I've had solid lifters on a motor for years (not a DOC though), and although it's not to hard to adjust, it's a messy PITA sometimes to do, if doing on a running motor.

Wags

[Smokie]

Our engines cam lobes move a rocker that pushes directly on valve stem. I don't understand what exactly is a roller cam in this application, I know what a roller lifter is, what the heck is a "roller camshaft" :confused: :confused: :confused:

[merc]

Dan Yerace (Ford Motor Company) and Dennis Corn (Roush Industries). The paper documents a maximum effort, normally aspirated, DOHC modular motor. They had to spin it to 8200 rpm to get 600 HP. It lasted for one dyno pull.

Understand that nearly every component of that engine was custom made. There was a redesigned FWD aluminum block, a machined main cap girdle (replacing the cross-bolts on the main caps), an 8-counterweight steel billet crank, custom forged pistons, forged connecting rods, redesigned head castings, smaller base circle cams and follower gear to reduce the follower roller speed), dual valve springs and Titanium retainers, mechanical valve lash and cam chain adjusters, dry sump, custom intake and exhaust, blah, blah, blah.

Modern production engines are designed to meet a specific target,with the aid of computer aided design and manufacturing. All the components tend to be matched to the desired performance goal. Changing just one component (like an intake or cam) in the system will not yield the payoff it once did. Also, they tend to not be overbuilt. According to the SAE paper, the 4.6 DOHC was designed for maximum output levels of 100 BHP/L. Beyond that, you're facing replacing a lot of expensive parts.

The modular motors were not designed to be user serviceable, either. No room to be bored. Non-rebuildable connecting rods. Oddball valve springs, press-lobe hollow core camshafts (four of them and not one of them cheap), etc, etc. Even if they were easy to work on, they've got some basic design features that make them less than attractive. The small bore limits valve area and thus the maximum air flow. A long stroke limits safe rpm, especially in the 5.4L version which gets its additional displacement all from stroke.

What I find interesting is that Dennis Reinhart and others have had problems modifying normally aspired Marauder 4V DOHC to achieve up to or greater then 300 rwhp with bolt-on parts only. Mad 3R has a built motor and I would love to see his new dyno runs. I remember reading some members totaling their modification cost and evaluating the gain ***ociated with investments. Supercharging is a hot topic on this site, and real performance gains that has been verified by many vendors and owners. What I am most interested in is the long-term reliability. I don’t think most people other then SergMac are worried about their rear end or transmission. Creating horse power and torque comes at a cost. Find the balance that fits your budget.

:pimp:

[Dr Caleb]

Good post merc! Well said!

[deerejoe]

...and your vehicle.

Nice post, merc.

[BillyGman]

I think those are definately some good points that you've made. I want to thank everyone who have shared their viewpoints in this thread, because that's what I've asked for.
Merc, I know what you mean about these hi-tech engines these days. It's like you have to be an engineer, and also have big bucks just to squeeze a significant amount of increased power out of them. The old muscle cars can be worked on easier, and can yield a significant power increase just by adding one component such as a bigger camshaft. And I'm talking an increase that can be felt, and that you don't need a stop watch or a Dyno just to know that your car is faster.
Smokie, roller lifters are made for the sole purpose of using a roller camshaft. Standard "flat tappet" lifters will not follow the more aggressive profile of a roller cam, because the Lobes of those cams have much steeper opening and closing ramps. That's why a roller cam will produce more power. The roller cam having more aggressive Lobe profiles causes the intake and exhaust valves to open and close faster. Therefore they have more time to stay open. And holding the valves open for a longer duration will get more fuel and air into the motor, which gives it more power. It also makes the exhaust flow better.
If you were to use a standard type lifter w/a roller cam, the lifter would skip or hop on and off of the cam lobe, and therefore cause severe valve float which would damage valves, valve seats, and eventually destroy the camshaft as well. Because of the steeper opening and closing ramps of the lobes on a roller camshaft, higher valve spring pressure is also required(ie heavier springs) to keep the roller lifter following the lobe profile of the cam properly. There are hydraulic, and solid roller cams, and the solid roller cams produce more power, and have even more aggressive lobe profiles than the hydraulic roller cams do, and therefore require even more extreme valve spring pressures. But ofcourse as it was previously pointed out in this thread, solid cams require periodical valve adjustments, and the solid roller cams often require that the lifters be examined and possibly rebuilt every 2500 miles.

[Murader03]

For anyone interested, the article is in the September '03 issue of Muscle Mustangs and Fast Fords, page 74. Work was done on a '99 Cobra engine, sligfhtly modified, but the huffer was left disconnected to simulate a N/A engine. The base line with stock rockers was 345tq@5000. 366hp@6300. After they replaced the stock lifters and rocker arms with solid lifters/roller rocker arms/ and cam, the numbers were 374tq@5000. 390HP@6300. That's the jest of the article. Can't pull the link from the magizines web site. The after market company is located in Perkasie, Pa. Granted the MM engine isn't a Cobra, but were close. I bet we have the same basic valve train as far as lifters and rockers go. Food for thought.

[BillyGman]

Thanx for the info. I'll check it out......as far as I know, the marauder uses the exact same cyclinder heads as the Cobra does......

[Smokie]

BillyGman, Thanks for that explanation, it was on the money! I was associating the word roller to "roller bearing" I guess I am more accustomed to the phrase "taller cam" or "lumpy cam" which I believe is about the same as "roller cam" and then you use the roller lifters and stiffer valve springs,,, Thanks again...I'm getting educated beyond my intelligence !!!!!:D :D :D

[BillyGman]

but your "education" isn't done yet BRO.......a "lumpy" cam is simply any cam that has a higher performance lobe profile and therefore will cause a "lumpy" or "Lopey" idle of the engine. But it doesn't neccessarily refer to a Roller cam. The term "lumpy" is just a slang expression whereas the term "Roller" is more of a technicle or specific term. You can immediately tell the difference between any standard camshaft, and a roller cam if you were to lay them both on a bench side by side. The roller cam has lobes that are shaped differently then the lobes of the standard camshaft.

[Smokie]

Well if I keep reading eventually I'll know what the hell I'm talking about,,,,maybe. :D Thanks.:bows: :bounce: :bows:

[merc]

I found this artice on SAE's website. I thought you guys might be interested in the cams they discribe. Given this interpretation of the cams, I would say the heads on the Cobra are different then the Marauder.

Mercury Marauder returns

The 2003 Mercury Marauder.

The first sign that Mercury would bring back the Marauder, which had its initial debut as a 1963 1/2 model, occurred at the 1998 Specialty Equipment Market Association (SEMA) show. Unveiled as a concept car at SEMA, the Marauder made its world debut at the Chicago Auto Show as a confirmed production offering for the 2003 model year.

Essentially the same car (although it sports different interior gauges and dark-tinted headlamp and taillight bezels), the production Marauder will have the same transmission (four-speed automatic with a high-stall-speed torque converter) and driveshaft as employed on the Crown Victoria police package, according to Steve Babcock, Marauder's Project Manager.

A 4.6-L, DOHC V8, producing more than 224 kW (300 hp) and 407 N•m (300 lb•ft) of torque, will power the rear-wheel-drive car. The engine is a modified Mustang Cobra powerplant that uses truck cams to allow for better low-end torque. "Marauder is the first performance sedan from Mercury in decades," said Mark Hutchins, President of Lincoln-Mercury Division and Vice President of Ford Motor Company.

The four-door sedan will have a 3.55:1 rear axle with limited-slip differential and a performance suspension. "The shocks, springs, and stabilizer bars are all unique to the Marauder," said Babcock.