2008darkhorsebullitt

My car is currently getting a vortech intercooled supercharger installed . Ive searched and searched for info regarding how much boost a stock motor's internals with 28,000 miles can handle ? Most have said 425 to the rear wheels but been that you can get an extra 20 to 30 hp just from long tube headers / cat back exhaust system / pulleys / aluminum drive shaft / not to mention all bolt ons .. how does that effect the the internals and what it can handle ? Is there a specific number of how much boost / fuel pressure / the pistons and rods can handle .. I chose not to dig into the motor just yet because it has low miles and i already 375 hp to rear tires just from bolts ons including cams .. I know this subject has touched on alot but im still curious

JCON

I don't have the answer off the top of my head but boost and horsepower are two different things. For example, the engine is safe usually to just around 500 RWHP on stock internals but if you were running high boost to do it you may blow your heads off (with out a stronger head stud kit). Alternatively, You could add a head stud kit to handle 20 PSI and blow your bottom end out. I have seen a lot of guys run high 4xx RWHP on stock internals. All they did was replace the clutch but it's around 500 that you need to seriously start thinking of building it because sooner or later you'll have to.

You will need to remove your under drive pulleys and put the stock pulley back on. Most guys run stock pulleys with a super charger. Having an aluminum drive shaft will artificially increase that RWHP threshold because it will require less work to turn it and that will result in higher dyno numbers but your engine is still technically making the same amount of power (just lower parasitic drive line loss).

outceltj

What has been done to the car to make 375?? Rule of thumb has been 450 some have had more with no issues and some with less and blown the motor. It's in the tune. I'd say if you don't have the money to replace the motor you may want to wait. It's also how you handle the extra power. Drive like an idiot and u will likely blow it

2008darkhorsebullitt

Every bolt on possible is on my car , ffrp intake , ffrp throttle body, ffrp cams , accel coil packs , pulleys , cold air intake , stage 3 clutch , lighter flywheel , long tube headers , hi-flow bbk cat x pipe , mbrp race exhaust , all suspension is re-done , custom tune and dynoed .. I know eventually ill open the motor and change it but i was just curious where or how they get the internals breaking point numbers !!

outceltj

Not sure where they come up with numbers. I'm guessing trial and error. I know some of the good speed shops will buy a mustang every time something has changed significantly to the motor and do their own R&D. Just make sure you find a good reputable shop to do the tune. Numbers don't mean a whole lot when tuning. Making sure all parameters are correct is what is most important. A Dyno queen is much different from a car that has an actual time slip.

tx_zstang

As mentioned, there have been many people who broke at different power levels. Some engines go less than 450, most are good to closer to 500. There is no single number. Tuning is a big factor as well.

The fact that you have the mods listed will help optimize power and breathe better, so that means you can run less boost and get power around 450 easier.

CMcNam

That actually makes a ton of sense, I never thought of it that way.

808muscle

IF you have an auto trans then you need to realize that in its stock form and hard driving on the street that auto trans wont last. All depends on how you drive it.

Nuke

The going # that I had always heard was 450 RWHP but that is without beating on it. There was an article about it which discussed all of the critical components and the weak link escapes me. But I DO recall that if you want to go beyond 450, it's forged internals for sure.

2008darkhorsebullitt

Thanks for all the info .. My mechanic said he will run a conservative tune to get 490 to rear wheels and from all the stuff hes built its a safe number and its worked really well .. But been greedy i want more power so eventually ill crack the motor open .. I did see a youtube video of a stock v-6 mustang running 600 hp from a turbo set up on stock internals .. Just food for thought