Forged pistons

If the timing and fuel curve are both correct, then the limit would be way up there around 30lbs.
We've run 20lbs. on cast pistons (accidently of course!) and didn't grenade anything.

But all of the high dollar parts will not save you if the tune is bad. It just gives you a slightly better margin of error.
Later,
Will
 
I read about that Will, fortunately you didnt do anything. I saw some go on ebay for 75 bucks, and they didnt have rings but still I thought that was a good deal.... I figured even if I wasnt going to run 30 it would still be safer to have the forged then not. how much hp would you get out of 30lbs of boost???
 
hasa68mustang":xsqzfrya said:
how much hp would you get out of 30lbs of boost???
i think the proper term to describe it would be "a buttload" or possibly "too much"
really depends on the engine build, xtaxi has a build planned that'll get 400HP on 15psi with an intercooler, triple two barrels, and a cam, if you doubled the boost on that one... you'd be breakin drivetrain parts pretty regularly

what's the rest of the engine gonna look like?
 
use a program like engine analyzer.

you can find out a good estimate.

--edit--

with some thought, i figured it would be best to reapproach this question differently.

set a goal for yourself.
what kind of performance are you looking for?
how much horsepower and torque are you trying to achieve?
what is your budget?

there are probably a lot of other questions you could ask yourself. but it seems easier to set a goal first. if you can answer the first two questions i can use engine analyzer to figure out how much boost you'll need, what kind of cam would be best, and other stuff like that.
 
Hasa68mustang --

Forced induction is a power multiplier, so you need to know the base HP of the engine being boosted to get any kind of answer. If you go through the calculations assuming common VEs, Compressor & Intercooler efficiencies, etc., 30 pounds of boost has the _potential_ of giving you a 260-265% HP increase. So, if your base motor makes 100 HP, 30 lbs of boost should give you 260-265 HP. A 200 HP base motor could potentially get to 530 HP +/-. Note I said "potentially"; there's a lot of wiggle room and assumptions to come up with that figure.

But I believe Evan put it best: It's a buttload of power.

However, with the intercooler running at 75% efficiency on a 75 degree F day, the intake temp would be around 150 degrees F (as an aside, if you tried 30 lbs boost without an IC, the intake temp would be close to 350 degrees F. If you piped it away from the intake, you could cook your next Thanksgiving turkey using the turbo as the ulimate convection oven...). Finally, using general rules of thumb from Ak Miller and Spearco on boost vs octane vs detonation needs, this motor at 30 lbs of intercooled boost will need a minimum of something like 114 octane to avoid detonating itself into the history books. Certainly, the factor I've left out is how long the engine will be at maximum boost (the longer, the more danger), but you get the idea.

And that's not saying anything about the engine being able to hold together mechanically due to high kinetic forces.

Hope that helps.

--- Barrett
 
i wouldn't be so sure about adding just that stuff. There's probably a lot more you can do to gain power without having to add a lot more boost.
 
Like Will said, if the tune is right, it'll handle a LOT!, but the weak link might be the rods, they'll probably bend before the pistons let go.

Alex
 
lol I was just curious, I wasnt planning on trying over 12lbs or so, boredome if anything I guess.... I like the turkey oven, although I dont think I would want to risk my motor for a turkey..lol
 
hey. i get bored and dream up some stuff too. if you'd like i'll still do some engine analyzer stuff for you.
 
Back
Top