luvthe440Aroush

ok i'm gonna get the 302 long block from fordracingparts.com it has hyper pistons, gt-40 heads

when i get done with it it will have somwhere around 375hp most likely so it will have alot of stress on the engine

how much risk am i running if i put a 9 psi procharger on those hyper pistons and cast crank?

if not a 9 do you think it would even be safe to run a 6 psi?


just a question but how much of a torque diff am i looking at whit 3:55 vs. 3:73's i'm just really concerened about the gas prices with the 3:73's but if i'm gettin like crazy extra torque i'm gonna do it o yeah and lets just say i have like....i dunnno its so hard to predict...lets say 350 ft.lbs.

joker

The amount of boost and power than can be held is really limited to the tune. There is no magical number as to how much a stock block can hold, but from what I have heard, anything over 500 rwhp is pushing it. High rpms tend to kill cranks more than power. Pistons tend to go because of detonation, which is typically a product of crappy fuel, a bad tune, or an inadequate setup. As far as the gears, with a boosted setup, 3.55's will be fine.

MustangFanatic

I'll second joker's comments. The lowest gear I would recommend is 3.55's if you plan on boosting the car at all. Anything lower (higher numerically) will create too much torque multiplication and blow off the tires on launch. Are you planning on running the car at the strip? If so, I would also recommend 31 spline axles and carrier as well.

luvthe440Aroush

so would you guys say the boost is ok and if so how much? this is a brand new block, and i dont know how much it cant support its the 320hp longblock on fordracingparts.com

i was more worried about a piston crank or ibeam snapping under the pressure

and i plan on running at the strip uncompetitive for fun on the weekends...other than that just a play car for fun.

luvthe440Aroush

if you dont mind i would also like to hear more about what causes engines to blow....you know like what rpm is dangerouse why the pistons blow and what causes all the problems with all that?

63galaxie

Well if your engine is set up right and you have forged pistons, which typically come in a 5.0HO, then you could get into the higher RPM's...i'll have to check what my tach has...i know it has a white range of lower rpms to (i think)4k, then yellow to 6k, then red all the way up to 9k, i wouldn't go over the redline of course but you'd have a brand new crate engine so you might could "abuse" it a little more
As far as boost goes i don't know much about that...

And for the explenation of blowing the engine--the pistons are just huge slugs going in a stroke and when it gets going fast enough its like a bullett going fast enough to beat through the crank and the block or break of the crank and shoot through the head

luvthe440Aroush

well i wanted forged pistons but this particular engine has hypers


so how much horse would you be able to safley put on the hypers?

MustangFanatic

Again, as stated before, it's all in the tune. You could run 5 lbs and be very lean/too much timing and grenade the engine, or you could run 10 lbs with the right tune and be fine.

As general rule, no more than 8 - 10 lbs with hyper-pathetic pistons. My advice would be to find a local shop that has done extensive supercharger installations on 5.0L Mustangs and coordinate with them on tuning which should include dyno time with wide band capability. If you don't have a local shop, consider contacting someone like Rick Anderson, he is one of the foremost Mustang S/C experts in the country and has tested every conceivable combination over the years. He frequently does tech articles and build-ups for 5.0 Mustang.

By the way, what intake and exhaust were you planning to run? What about the fuel system? You will need bigger injectors and a higher volume fuel pump at a minimum. Are you planning on running an FMU? Having all the right support pieces is critical in a S/C application.

63galaxie

I beleive that all 5.0 HO's after 1987 came with TRW forged pistons, you could salvage those from somewhere. then you could support a lot more with those pistons if you are possibly thinking about more boost or nitrous...

luvthe440Aroush

i will be running a trickflow intake, with the mass air and 42# injectors with a 255lph fuel pump

i dont know if you have heard of them but my local shop is ford speed and i know the owner.....da*n 2 years prior idle wild racing was open here i'm sure you've heard of them, featured in 5.0 magazine on multiple counts

they built my fathers 5.0 ranger (320 rwhp)


o yeah i for got to mention just as a drop in
no emmisions in florida YEAH!

joker

Nope, in 93 they switched back to hyper pistons in production 302's

joker

Like mustang said, it is all in the tune. Hypers are fine, even above 10lbs of boost, if the tune is right. I can push 14lbs on a six cylinder with hyper pistons all day long. It is detonation that kills the pistons. However, with increased boost comes the increased chance of detonation, which is why it is only recomended to stay around 10lbs. Another thing to consider is your compression ratio. This plays as much as if not more of a factor in the chance of detonation. An 8:1 setup is gonna have alot less chance of detonation than a 10:1 setup given that the two vehicles are pushing the exact same amount of boost.

Valentino

Just remember, even if there are no emission laws in Florida like you say, some items like catalytic convertors are still covered under Federal law. The fine for removing functioning catalytic convertors is $10,000 PER cat. So you may want to keep that in mind when choosing your exhaust for your buildup.

63galaxie

My mustang doesn't have cats on it...I don't know how law enforcement can tell unless they acutally inspect its underside...and they won't do that as long as you have a respecably quiet muffler.

Regards to the hyper pistons in '93---you are right i just looked over which year they changed to TRW forged pistons I didn't bother to look over the other years(got it off of mustanggt.org)

luvthe440Aroush

i know about the cats....my father has been running 3 cars over the past 15 years without them...they really dont bother checking....

thanks for all of the information...i think i have squeezed the most i'm gonna get outta this post

as far as compression the engine comes 9:1 and i dunno how much the supercharger will add.

joker

9:1 is fine for a supercahrger, as long as it is nothing extreme. If you were gonna push a ton of boost , you would want something more around 8:1 but that is fine for your typical supercharger setup.