4.6L Cobra block rebuild!

RiCeEater said:

I recently threw a rod through my beautiful 2002 Mustang GT, it was putting down 353rwhp, 329lb-ft torque, Supercharged, forged pistons, 38lb injectors...very sad. Anyway, Im planning on rebuilding the shortblock, I've found an 03 Cobra block that I am going to use for the build but am wondering where I might be able to find some billet rods, cams, headers, pistons, and a good flywheel, the GT transmission will bolt up just fine.. I might hook up a 150shot of nitrous too..so I will want the cams to be able to work well with nitrous if I chose to go that route. I will keep the S/C on there and Im going to run around 13-16psi, Hopefully after all is said and done I will have around 800HP at the crank...Hopefully! Please Help! Thanks! BTW trying to stay in the $4-5k range.

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How many miles did it have when it threw a rod? Do you think the supercharger was the reason?

Did you have the car tuned after you put the blower on?? A blown GT with a good tune should be making way more than that. I've got almost that much torque and I haven't even lifted a valve cover yet.

Modular Powerhouse has all the stuff you need. Do you have a dyno sheet you can post?

The gas is what caused you to throw the rod. Sorry to hear that. Whoever tuned your car didn't put crap for timing in it if you were only making 329 ft lbs of torque.

Just an FYI, Nitrous kits never come with everything you need.

I would seriously think twice before putting N2O and a Blower on one of these motors, especially if you're not going to replace that stock plastic manifold. Also, check out your pistons real close, have them magnafluxed to make sure none were damaged when the engine kicked the rod. It would suck really badly if you did all that work and an unseen flaw in a piston made you pull the motor again.

Yah I have heard that from a couple people i think I am completely rethinking putting nitrous on the car, I think it will be fast enough without the nitrous plus after this weekend messing with my friends 150 and 175 shot in his camaro I have basically talked myself out of it.. The pistons I was really unsure about becuase i saw that there were two options Flat tops, or domed shaped...which are better with a blower? They both said that they were made for Turbocharged/Supercharged applications but didnt say specifically which one would be better for what.. As far as the Cams, Rods, headers, and the Flywheel I think all of that will work just fine....

My biggest question though is will that block bolt up to a 2V GT engine..I havent seen anything that would make me think that it wouldnt but do you guys think that theres a chance something may not fit properly..I guess i could call and find out all the little specifications so i dont have to spend more money having to redo something...

You want to think about your compression ratio when you build this motor. You don't want dome pistons. Those will raise your compression ratio. You want to think about how much boost you plan on running vs. the compression ratio. Personally I would consider running about 8.5 to 1. With the blower at 13-16 PSI, you should still be able to run pump gas and make some good numbers. You may want to talk to a combination of engine builders and tuners to figure out if running a slightly higher compression ratio and lower boost might yield you the numbers you want. The power is all in the tune. Make sure and do your research and don't rush it.

Comp Camshaft specs..

Duration @ .050 - 226 (intake) / 230 (exhaust)
Advertised Duration - 262 (intake) / 266 (exhaust)
Valve Lift @ 1.825:1 ratio - .550 (in/ex)
Lobe seperation angle - 113 degrees (in/ex)

The cams above look good,what do you guys think..and it also says Valvesprings recommended but its an extre $224, should I go ahead and get em? do I even need them? can I get them somewhere else cheaper?

That block you listed is a 4.6 GT block. It says "Perfect 2003 Cobra Buildups!" but it is not a cobra block. From reading up on blocks, I have found out the 96-98 Cobra blocks are the strongest 4.6 block made, plus they are aluminum. The 03/04 Cobra Blocks are next, and they are iron. With that much power I would only choose one of the above.

I found a few blocks..lemme know which ones you guys think would work for what I am trying to do. http://www.seanhylandmotorsport.com/bare-blocks_4.6-5.4.shtml

Just buy one man, look:http://www.dssracing.com/

Those blocks seem pretty expensive to me. Check the corral classifieds you should be able to pick up an aluminum cobra block for ~300 or so