daem0n

I was re-reading my Modified magazine from December and was checking out RE-Amemiya's Rx-8 nicknamed the "8-Turbo". I don't understand the power from the engine. I know the Renesis has a stronger engine but can you explain this: The Rx-8 is quoted as about 238HP stock at the flywheel and 159lb-ft of torque...but the upgraded TD turbo on the Rx-8 makes the new numbers 260WHP and 325lb-ft of torque! How does the turbo have so much of an effect on the torque? How come you don't see any Rx-7s with more torque than HP? (or maybe I just don't see them?) Anyone care to explain?...

Also here's the car:

http://www.re-amemiya.co.jp/rx_8/

jimlab

Where did you see 325 lb-ft. of torque? My guess is since the rear wheel numbers are in Kw/PS and not horsepower, that the units of torque are not lb-ft.

Lack of displacement.

turbojeff

iTrader: (30)

325 lb-ft is too much for a high revving 260rwhp car. Probably meant 225ft-lb.

HP is a function of torque * rpm with some unit correction factors.

daem0n

yeah you guys are probably right. I looked for torque on the website but couldn't find it. The magazine quotes 325lbs in a couple places so they probably just don't translate Japanese very well lol

jimlab

Well, 325 Nm (Newton-meters) would be about 240 lb-ft. of torque.

ratincat

well i just made 340hp and 513 ftlbs torq with stock ports and a t78

turbojeff

iTrader: (30)

Very low HP for that torque.

daem0n

How does that work?

GoodfellaFD3S

iTrader: (213)

No, you definitely didn't.

kuroi FD

how is that possible?

ratincat explain?

KrisRX71993

yeah, HP seems too low

Red-Rx7

lol. That is nearly impossible with a stock block & a T78.

At 5600 RPMS, and if you made 340 HP, that would equate to 318 ftlbs of torque.

At 5400 RPMS, and if you made 340 HP, that would equate to 330 ftlbs of torque.

At 5252 RPMS, and if you made 340 HP, that would equate to 340 ftlbs of torque.

At 5000 RPMS, and if you made 340 HP, that would equate to 357 ftlbs of torque.

At 4800 RPMS, and if you made 340 HP, that would equate to 372 ftlbs of torque.

At 4600 RPMS, and if you made 340 HP, that would equate to 388 ftlbs of torque.

At 4400 RPMS, and if you made 340 HP, that would equate to 405 ftlbs of torque.

At 4200 RPMS, and if you made 340 HP, that would equate to 425 ftlbs of torque.

At 4000 RPMS, and if you made 340 HP, that would equate to 446 ftlbs of torque.

At 3800 RPMS, and if you made 340 HP, that would equate to 469 ftlbs of torque.

At 3600 RPMS, and if you made 340 HP, that would equate to 496 ftlbs of torque.

At 3400 RPMS, and if you made 340 HP, that would equate to 525 ftlbs of torque.

So, that would require a pretty large & broad power band to achieve that torque. And if you are using "stock" ports with a T78 & 13b, I wouldn't ever believe it.

cloud9

iTrader: (4)

/\ serviced...

t-von

iTrader: (8)

Come on guys, he never said what engine he's running. Those sound like Diesel hp figures.

Red-Rx7

Yeah, but he said "stock ports". To me, that is showing ROTARY. You bore/stroke a piston engine. You port a rotary.

He also said he was using a T78, which is a Greddy application. These are typically specific to application purposes (ie to an engine, for this is a turbo "kit") from Greddy.

For someone to put it on some other engine, would be stupid. You could build and make a custom turbo kit for less (without having to throw away specific parts), and have it be more specific to you actual application.

Greddy makes the T78 turbo for the following applications:

Toyota MR2
Toyota Supra
Nissan 300ZX
Mazda RX-7
Mitsubishi 3000gt
Mitsubishi Eclipse
Suburu Impreza WRX (and STI)

There is the possibility he just ordered a REPLACEMENT t78 turbo from Greddy (again, not cheap and .. odd..) to use for his application. But if that was the case, he didn't research turbos very well, for he could have had a custom one built for the same price.

daem0n

What happens when you increase displacement in the rotors? Sometimes you see some bored-out rotors. Does it increase torque at all?...shorten engine life?, etc

Narfle

iTrader: (16)

it was a joke, he posted his dyno sheet and it was wrong he was just kidding

crazy people

billyrohm

hp = (torque X RPM)\5252

jimlab

Thanks. Jeff didn't know that.

kenn_chan

Oh come on now I have a 12AT quadriple port with a AE 101 turbonetics turbo, a big honking fmic and a stock fuel pump, and I make 613 hp at the flywheel and I only make 511 ft/lbs of torque. Oh and my ralliart stickers add another 5mph due to a lower drag coeffiecint

kenn

ratincat

its the full greddy turbo kit

Jason

iTrader: (5)

I tuned ratincat's car. The 513 lbs of torque he saw was not the correct graph for his car. The torque was closer to 300 lbs if I remember correctly. He is running a T-78 on stock ports and made 340 something on a mustang dyno at 14lbs of boost.

Jason

ErnieT

iTrader: (2)

Dude, I've seen some BULLSHIT posted on this forum, but this is the biggest piece of BULLSHIT I've ever read!!! Go back to highschool and impress those people w/ your crap, not here.

FCdemon

lol... you people need to simmer and realize that a joke is a joke.

ErnieT

iTrader: (2)

He never posted he was joking. And by everyone's reaction, you'd think he'd say he was joking or defend what he said. (although it can't be defended)..........lol........