GWFoos

I just got done talking with modular mustang racing and discussed adding the aforementioned strengthened bottom end to the GT. It sounds as though something like this would be the way to go for an auto tranny due to the stock motor needing upgraded internals at around 400rwhp.

MMR and I discussed many modifications in addition to the engine discussion and I wanted feedback here as to whether to change the bottom end as I would like to get the sc on there in the future.

BTW, the other motor was the 4.6L Mod 700 motor, which can take up to 700hp.

Are there things that I am missing as far as cost goes (they said $1400 to do full removal and disassembly of the stock motor and reassembly)?

Thanks in advance.

Getaway

If I were going high horsepower like 700 or so like you are suggesting, I would build up the bottom end, throw in some forged internals, lower the compression a bit (to like 8.6ish), and see how much air I could force into it with twin-turbos or a LARGE supercharger.

As far as pricing goes...labor costs change, and most people I know that do what you're planning own their own machine shops and do the work themselves...free labor.

Oh, and stock engine internals should handle 450ish (500? maybe? scary!)...the tranny is subject to failure around 400ish. I don't really think getting mega power out of the engine is that big of a deal...getting it to the ground will be a wallet ripping headache!

GWFoos

What would your suggestions be?

I want an automatic and I was told that 400hp is pretty much top end, whereas the manual would be closer to 450hp on the stock motor.

The stroker engine has forged internals (www.modularmustangracing.com). I was not looking to put 600hp to the ground, but I didn't want the sc to be limited by the stock motor to 400hp.

I want fast, but not without reliability. I have contemplated the Whipple sc, but the auto tranny is what stands in the way and I don't want a manual.

Any help would be appreciated to keep costs down, if possible.

Getaway

I agree with MMR for BIG muscle power....
Forged rods (little shorter than stock), Forged pistons, and a thicker head gasket all to lower the compression and add strength thus creating the extra 4/10L = 5.0L Then add a turbo/supercharger/nitrous...boost...great, however, this is all to the engine.

I'm not sure you really understand that it's not your engine limiting your power to 400rwhp...it's your transmission. You see, an engine producing say max (safetly) 500 crank hp loses 10% of this power due to drive train loss with (the MANUAL tranny)==450rwhp...the same 500 crank hp engine experiences a 15% drive train loss with (the AUTO tranny)==425rwhp.

The problem with the Mustang is the Auto tranny "may" crap out around 400rwhp even though the engine could really be pushed beyond that...on stock internals.

Therefore...you can build your tranny up to go beyond 400rwhp, but the engine would then become your limitation at 425rwhp. If you wish to go beyond that, then you get into modifying the engine internals AND making pump gas a thing of the past since your car will now crave race fuel.

If you want the inexpensive method of high power...cam swap is the way to go....I think in the manual mustang with forced induction, 450rwhp is the max power available on pump fuel...the auto is around 425rwhp (if you build the tranny to surpass that 400rwhp mark).

I hope this helps...If anyone wants to add to this OR CORRECT ME somehow...be my guest as I'm not easily offended.

GWFoos

If I was to replace the bottom end (with forged internals), add the sc (with a custom calibration), and rebuild the tranny, what would be the hold up on that?

My discussions with a guy at Whipple discussed the rebuilt tranny and custom calibration of the sc and the MMR guy was saying that the bigger motor with forged internals would allow for up to 600hp. Am I missing something? My understanding is that this could be done on 91 octane fuel per the Whipple site.

Getaway

600hp at the wheels on 91?? I'd like to see it...even with the lowered compression. That's BIG. At the crank...sure, why not. I'd say the extra 4/10L "could" maybe be worth the extra 100 crank hp or so with the forced induction...I dunno...better get an intercooler. None of this is cheap though. I know this is just words on the internet, but you make it sound like it's not going to cost much...I'd say $7,000-$10,000 to get to that "600hp".

Have we even mentioned tire maintenance, brakes, or suspension...No. You'll need to upgrade that stuff too to put that kind of power to the ground. Drivability...well, keep a good distance between you and the car in front of you, because you're getting out of the daily driver category for your car. I think you need to ask yourself if you want a really fast car, or a drag car...MMR appears to build the latter.

There's insurance for modified cars like this...I suggest you get it before attempting these mods.

Overall..I think it's possible, and would definitely be a whole lot of fun...but if you have the money, almost anything's possible. I say do it just because I wanna see it, but I'm not paying for it am I?

GWFoos

I don't want 600hp, more in the 475hp range. If there are cheaper ways to do it, I am still learning. As for the money, I didn't mean that it was cheap, only that it is cheap compared to any car you would buy that had that kind of hp. $7-10k is doable for me right now. Now if I can do things for less, great.

Shifty

Does anyone actually have personal experience with a 450+ hp '05 to back up these "the tranny will fail" claims? They all sound like that connecting rod bs that meant you couldn't supercharge the 05.

Getaway

475 is an odd number. "possibly" too much for stock, but all that work you're planning seems like overkill for that. As Shifty is saying...the car's not really fully tested yet. If you do this stuff you're planning....[sm=hail.gif] thank you for doing it first because I'm not too far behind you...when I get my 05...

but unlike you, I plan on turning my car into a beast after driving it stock/mildly tuned for a while (after good people like you experiment with it of course ) and I'll buy something else to commute in when that time comes.

sicride

I would look at it this way... What would it cost to rebuild the stock and what would it cost for the new engine.. a rebuilt engine will hold up to the 450hp no problem. If all you want to do is get a supercharger kit and run it reliably then I would assume rebuilding your current engine with lower compression and upping your boost alittle with a new pulley (I think the original pulley creates 8psi? maybe get a 10-11psi pulley) and upgrade your fuel system including cams. I'm sure you would be putting down PLENTY of safe horsepower at that point.. Most likely in excess of 475RWHP. The tranny would also need a rebuild for sure with or without the internals of the engine done. Get the torque converter and valve body upgrade with the tranny rebuild and make sure you have enough rubber to keep the thing moving forward.

P.S. I don't think he's too concerned with the money side of things. So do it right thefirst time with good stuff and you wont regret it.