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Hi does anyone know how much horsepower 50psi of boost would add to a 94 supra factory turbo the car has been built to handle 1500hp+ horsepower but I just want to know how much power 50 psi would add


Thanks
 

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Pressure is just a force-per-unit-area measurement that's relative to the system it's contained in. Key word being relative. Look up the ideal gas law (PV=nRT) and understand how temperature affects pressure directly and you'll understand how flawed it is to compare boost pressures between totally different systems, and that boost pressure is not a universal measurement even among the same engine family.

That said, horsepower is based on moving air Mass not air pressure. How much mass you can move through the engine determines horsepower, how much pressure that is inside the intake manifold depends on all sorts of other engine variables.

A turbo capable of supplying 1500hp worth of air mass (which is why turbo flow is measured in lbs/min for the most part) might supply that 1400-1500hp peak at 16psi of boost on a huge aluminum big block V8, but it might take 45 or 50psi of boost in a built/sleeved 2.5L engine of some kind. It all depends on the cylinder head flow, VE of the engine, turbine housing/exhaust port flow, intake temps, intake temp delta from the intercooler, the fuel being used, etc. There's a million variables here and you're looking at one number as if it tells the whole story.

To answer your question simply, there's no way to know unless you get very specific about the engine and turbo configuration. Everything else being identical, 30psi from a smaller turbo might make 750whp, and 30psi from a much larger turbo might make 1100whp.

How much does it cost? More than you can afford, pal, Toyota Supra.
FnF jokes aside, most true 1500-1600whp capable builds involve around $20k-25k in the longblock, $10-15k in the turbo setup and intake manifold/intercooler etc, and another $10-15k in the fuel system and ECU. Add in another $10-20k for a transmission package that can hold the power, $10k give or take for a proper Ford IRS 8.8 or 9in conversion for the diff and rear end, and probably another $10k-15k or so in proper wheels/tires/brakes/suspension etc. Then another $10-15k for a proper 25.2 rated cage install and fire suppression system and parachute and all that fun stuff.

So figure a nice $60-80k Supra and another $125k USD to build it and you can have that 1500whp Supra.
 

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@Wreckless

You bring up a very intriguing thought.

I always see ALL these high HP builds but not many discuss the safety side needed to be able to compete (due to sanctioning body requirements, much less to survive) on tracks.
 

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Is this a how long is a piece of rope question?
 

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@Wreckless

You bring up a very intriguing thought.

I always see ALL these high HP builds but not many discuss the safety side needed to be able to compete (due to sanctioning body requirements, much less to survive) on tracks.
It's very specific to a given sanctioning body, so any plan for it depends on the rules involved. Given the advancements in tires and ECU based traction control, I'm all for 600-800whp street cars that are kept mostly stock as far as safety equipment - but once the discussion gets north of 1000whp you'd be fucking insane to not consider fire suppression and at least a half-cage.

In fact, once you touch the fuel system in a car and start going to AN fittings and the like, a Halotron or other very effective fire extinguisher should be mounted in easy reach of the driver's seat. Right in front of the passenger seat with a bracket held on by the front passenger seat bolts is ideal.
Just the other day I met a local guy with a stupid clean FC RX7 Efini, RHD and all, and he was telling me about a friend of his who had a 3-rotor Eunos Cosmo burn down on him. A couple hundred bucks of prevention might have saved an irreplaceable $60k+ car.
 
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ESS has a neat system that is refillable, uses a CO2 cartridge to push the foaming liquid out through the nozzles when the AHHH-FIRE!! handle is pulled. Have one nozzle aiming at the exhaust side, two aiming at either end of the fuel rail ...


It's only a few hundred $$ for peace of mind. An extinguisher in front of the passenger seat is all well and good (I've had one for years already), but they're small and won't last long. I would rather yank a handle as I get out of the Supra instead of futzing with the bonnet release etc. to get access to the flames. Would still have the extinguisher in hand though just in case ...
 
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