bobsmilie2000

How much horsepower do you think the stock crank can take on a 2005 Mustang GT?

GJP05

About 600hp but the rods and pistons will give well before that. If your going to replace those then you might as well replace the crank while you are in there.

bobsmilie2000

GJP05... I'm not trying to be rude, I'm just asking, but how exactly do you no that. Is there a page on the internet you use that offers that info? Also, do you know any sites that sells forged crankshafts for the 2005? Besides that 8-bolt Cobra of course. I'm trying to save money by not purchasing a new flywheel.
Thanks.

GJP05

The crankshaft is made from the same nodular iron as previous models. I have already pulled mine out and replaced it with a Kellogg crank. There are a few shops you can get a forged crank from but they will all be 8 bolt. Now you can replace just the pistons and rods but the reliability of the engine won't be the same as if you go with a complete forged bottom end. You can search on the forrums and e-bay for a used crank and get one for cheaper but you won't know what kind of abuse its gone through. Remember cheap, fast, or reliable you can only have two of the three. What are your plans for your car? What type of power adder? What rwhp are you looking for? How long do you plan on keeping the car? These questions will help you determine how your engine should be built.

bobsmilie2000

I'll be keeping my car forever. I'm just impatient to save money. But I would rather be doing it right and know I'm not going to kill my engine. Do you think if I kept my car under 600hp, would it be ok with just new forged pistons and rods for a twin turbo? No new crank or flywheel. Also, over 500hp will a new clutch be necessary?

GJP05

Over 500rwhp you will need a new clutch. If you plan on keeping it below 600 hp forever then yes rods and pistons will be fine. If you ever plan on pushing it past that you will end up paying to rebuild the engine for a second time. In the long run this will cost you thousands of dollars just to save a few hundred now. If you are goin with a turbo then it would be a waste to keep it below 600hp. Also it will be easier and cheaper to replace the clutch and flywheel at the same time. The stock crank and clutch may hold if you keep it below 500hp but it won't do so for very long. Your best bet is to have someone build you a forged short block and then sell your block to recoupe some money. Now since you plan on keeping your car you don't have to worry about the numbers matching so this is the best route for you. Also the stock tranmission won't hold up for long at those power levels. Now you can do a little bit of work at a time to save on paying a big chunk of money but in the long run when you figure that each time you add something you will have to break down what you built before you can build it back up you will end up spending twice as much. Even at 500rwhp there is a long list of parts you will need besides whats in the engine.