Internals

[MunsterBro95]

So, buying the motor this week from Marty and shipping it here. I know some will say just do it now, but wont have the funds until the summer and would rather do it next winter while its stored. Going to put the motor in and drive it this summer, babied. Next winter once its stored, I want to take the motor back out and rebuild it, it has 173,000 miles. Rather do it now when i am not in school and can take time off work and can afford it. Want to set it up to handle boost later, decided i am going to stick with the 4.6L. My question is, what internals should i go with and what should i replace on the motor? already plan on upgraded brakes and all next year, but not sure what to do for motor. I want to do Forged internals. Has anyone does this on the iron 4.6? as said before i dont know alot about cars so i am learning. Just trying to get advice. looking to have about 450hp. dont need too much more as i dont plan on racing it. just want to modernize and update it while giving it a little more power, if that makes sense. Thanks for the help. HAPPY NEW YEAR!!

[Turbov6Bryan]

It's a aluminum 4.6 block known as a WAP block. Makes 302 horsepower
Adding forged rods and Pistons , it'll still make 302 horsepower

Increased strength in the rods and Pistons is for boosted or nitrous marauders
Upping the power with boost puts a strain on the oem pencil rods, that's why they break
Too much power and the oem rods are weak


I'd put the 173k engine in, toss Marty tune in it and enjoy it

Spend the money on a blower kit with a safe tune. Then build the engine

[MunsterBro95]

oh i thought the marauder motor was iron

[Turbov6Bryan]

Have you read wiki on them?

[Ambitious1]

oh i thought the marauder motor was iron

You may be thinking of the Cobra block, which is cast iron. The MM is aluminum. The stock aluminum Mach 1 in the MM will not handle much more than 450+ without modification.

https://www.svtperformance.com/forums/threads/difference-between-03-mach-1-and-03-cobra-motor.508422/

http://www.mercurymarauder.net/forums/showthread.php?t=18590&highlight=cobra+engine+differe nce&page=2

To quote SergntMac:

"The MM, Mach 1, Aviator and Cobra all share the same 4V DOHC design, and all parts are interchangable, which Ford likes to do every year, just to keep threads like this open and humming. The chief difference is what is used inside. The MM gets a cast crank, I beam rods and hypertetehatever pistons. The Mach I gets the same engine with a "right handed" upper intake manifold, unless it's mated to a manual tranny, then it gets steel forged crank.

Cast cranks are six bolt, forged are eight, still, performance-wise, the engines are fairly similar. Only the Cobra engine is hand fit together, and it's not every little piece as in hand built, it's assembly of component pieces, with signatures on the valve cover. Nice touch, SVT.

The Cobra is not an easy engine to trace or track, a specific configuration depends on the year it was produced. It may or may not have an aluminum block, and it may or may not have been supercharged, which affects compression ratios. You really have to treat each Cobra short block individually, nonetheless, the Cobra is known for it's steel forged crank and H beam rods. It uses the same piston as the Marauder and the Mach I, same hyperwhatever material, but with minor adjustments to configure compression.

The high compression Cobra pistion (in some years) is a true 10.1:1 compression, and the Marauder/Mach I piston has a 3cc dish, which cuts compression to 9.8:1. At other times, the Cobra piston uses 8.1:1 compression, and if you were to hold that piston side by side with the MM/Mach, the only visual difference is the thickness of the piston above the top ring, and the dish top."

[MunsterBro95]

That's what I was getting mixed up was the cobra and ours. My bad. And so are you saying I should change to forged or stay oem?

[RubberCtyRauder]

you'll want forged internals if desiring to supercharge it one day..timeframe and budget to either get it running/driving vs all built up and supercharged. MIne's supercharged and at 455 rwhp, but I'm ready to take it to 550 rwhp which means time and $ and sending the car to Marty. I have forged internals already, stock block which is good for 1000 hp anyway. I just need bigger blower etc.

[MunsterBro95]

you'll want forged internals if desiring to supercharge it one day..timeframe and budget to either get it running/driving vs all built up and supercharged. MIne's supercharged and at 455 rwhp, but I'm ready to take it to 550 rwhp which means time and $ and sending the car to Marty. I have forged internals already, stock block which is good for 1000 hp anyway. I just need bigger blower etc.

What did it cost roughly to get all the parts for the internals and do you recommend any brand?

[RubberCtyRauder]

I bought mine already upgraded internally as the previous owner bent some stock rods with 450 rwhp. So he had it rebuilt with them so I don't really know cost wise.

Diamond pistons are in mine and Eagle rods. They are fine quality, some people like old hot rodder names like Manley


I do not have part numbers, rods and piston upgrades ususally go by motor and not car..alot of stuff for marauders are bought as if going into an 03-04 cobra mustang for instance

[RubberCtyRauder]

A quick search at summit racing show EAGLE forged 4.6 ford modular rods for about $560 and Mahle pistons were around $800 for example, but will need rings,wrist pins

[Ourobos]

Stock internals are good for 400hp or so, mine makes 10 psi and 392/406 to the tires. If I were to built a shortblock for big boost later, definitely get some good pistons, Diamond, Mahle or the likes. You can pick up good usable 03/04 Cobra cranks and rods for about $400 per. I'd stud the bottom end and even the heads, and put ARP2000 bolts in the rods. That is a bullet proof combo, I've built two, but were for Mustangs.

[Mercury Madam]

its the pistons and rods that are suspect on the MM, unless you want over 600 hp, otherwise @450 hp
the crank should work!

[Ambitious1]

You will definitely want to start researching supercharging, including all of the mods necessary to the engine and possibly, the transmission. Factors in price will include whether you're doing it yourself or not, the individual parts and tuning as well.

http://www.mercurymarauder.net/forums/showthread.php?t=80327