ArchangelX

I was just taking a load off my mind (literally ) and I was perusing one of my older Import Tuner mags (I bought it cuz it had an FD in it) from January 03.

Anyways, there's an FD nicknamed "Evil Twin" owned by a guy named Jack. (no last name apparently). It's a very clean FD, very well done, and would probably win several car shows, but I digress..

In the article, it says it was tuned by Peter Farrell. This is a direct quote from the article:

Quote:

The modifications began under the hood as Jack concentrated on upping the 13B powerplant's performance potential. Farrell installed a PFS intercooler and intake along with a stainless-steel 4-in. downpipe. The exhaust gases are exited via a 3-in. Random Technology cat into a GReddy stainless-steel exhaust system.
The stock twin turbos are controlled with a PFS custom programmed ECU that includes three-way boost control. Running 17psi of boost, Farrell estimates the 13b is generating around 420 hp. In the interest of longevity, Jack normally keeps the boost level down to around 9psi and estimates the output at 320 hp. As extra insurance against destructive detonation, a J&S knock sensor adds timing retard protection.

Okay...reading that..here's my question.

I thought 400 was the magic number on the twins....and that noone has really pushed them past that point yet.

The 320 is a believable number..but only at 9psi? That doesn't sound right at all even with basic mods.

Is this a buncha BS?

Engberg

420hp at 17psi sounds a bit out of the stock twin efficiency range, blowing smokin hot air..atleast thats my guess. On a turbo car, how can you raise the hp nearly 100 hp while lowering boost 1psi? Airflow is great and getting the air to and from the engine easier I can understand for about 30-50 hp (we are talking rwhp right?) but there wil be a smaller volume of air at 9psi. Sounds wrong to me..but just a guess

ZoomZoom

iTrader: (2)

Looks like the motor is producing an Estimated 420. Thats not at the wheels. Sounds right. Or at least optomistic

Mahjik

iTrader: (1)

Keep in mind that the word "estimates" keeps appearing....

I can estimate that my car will have 450hp, but that doesn't mean anything unless I have a dyno sheet.

IMO, I wouldn't even worry about it. Unless there is a dyno sheet there really is no way to validate or invalidate the "estimates".

BoostedRex

He could've been running non-sequential, but still sounds awfully high for stock twins.

As far as 400 on twins, that has been done by BNR supercars with the Stage 3 upgraded twins. We've all seen the dyno sheets for that. If you haven't seen them yet, just search for BNR stage 3 and you should run across those posts. Just wanted to throw in my .02 Laterz.

Zach

ArchangelX

Yepz..I know about the BNRs...that's irrelevant, though.

I'm talking STOCK twins.

The article didn't say anything about fuel upgrades either....

It just kinda piqued my interst after doing all the reading that I've been doing lately as far as power output on the stockers.

BS'ing is one thing...BS'ing in a major publication is something altogether different.

ZoomZoom

iTrader: (2)

The quote specificly states the engine. And they have to estimate it as PFS didnt have an engine dyno last I knew. Electromotive next door has one. But they didnt test it as they were just giving estimates anyway. Dont let it bug you.

Mahjik

iTrader: (1)

Hell, I thought all the import mags had BS in them?

However, we have seen 400rwhp on stock twins here, so if they are just talking about 420bhp, that should be doable. As for fuel mods, I'm sure they didn't go into extreme detail as to everything that has been modded on the car, just the highlights.

kwikrx7

It's obvious that it's at the flywheel because he's running a HF cat - it's been proven than a midpipe will gain you atleast 25-30 rwhp over a HF cat (peak) - there's not way in the world anyone could put out 420 rwhp on stock twins - especially with a HF cat - even the 420 at the flywheel is pretty optimistic but doable.

Kento

Quote:

The modifications began under the hood as Jack concentrated on upping the 13B powerplant's performance potential. Farrell installed a PFS intercooler and intake along with a stainless-steel 4-in. downpipe. The exhaust gases are exited via a 3-in. Random Technology cat into a GReddy stainless-steel exhaust system.
The stock twin turbos are controlled with a PFS custom programmed ECU that includes three-way boost control. Running 17psi of boost, Farrell estimates the 13b is generating around 420 hp. In the interest of longevity, Jack normally keeps the boost level down to around 9psi and estimates the output at 320 hp. As extra insurance against destructive detonation, a J&S knock sensor adds timing retard protection.

ArchangelX

REPOST:

ArchangelX

Okay..so is 320hp at 9psi doable with his mods without a streetported motor? I'm looking at the pics of his engine bay right now.

So far from what I've seen..his mods are:

PFS Intercooler
PFS Intake
HighFlow Cat
Midpipe
GReddy Exhaust
PFS ECU

At 9 psi..is this enough to generate 320hp? Granted they are estimates..but what I don't understand is how the hell you can do all that work without getting it DYNO-TUNED?

Does that make sense? I mean..you can't just slap an ECU on and expect it to run perfectly..some tuning is required isn't it?

I dunno..I'm pretty riled up after reading all these ignorant articles about RX-7s in the mags as of late. The SCC one really kinda ticked me off.

Kento

IMO, not unless there's a lot of involved (although maybe non-seq?)

You'd need some pretty damn efficient low-end turbo specs to get dem numbers...

GarageBoy

It's Import Tuner, what do you expect?

1FooknTiteFD

it has to be 420bhp. If you go to the PFS website, on the greddy single turbo kit, he rates his 500hp kit with flywheel horsepower not rear wheel horsepower. btw, where's rikki? Maybe he can shed some light

ttb

don't think you can have a midpipe and hi-flow cat at the same time. 320 at the crank would be about 270 (15%) at the wheels...if i remember correctly i remember somebody said he got around 235 stock, very healthy motor. so mayve with a very very healthy motor you can get 270 at 9spi, but i still doubt it....or maybe he is using a 20% estimate. that's only 256 at the wheels, which is pretty doable.

ttb

or maybe his boost guage is bad

Engberg

Maybe I can send pictures of my stock 1993 VR Touring and say my 13 psi overboost is on purpose and I figure I'm putting down 350hp because of it. Import mags used to be decent in the hay day...but they'll put any garbage it in now adays. And sport compact, even though many import kids think it is the most technically advanced and indepth mag out there, is the king of all BS, especially their technical editor who uses his highschool physics book way to much...
[changing topic here but had to get that mother out ]

Richierich

I had about the same mods and I dyno'd it at 308 at 16psi....so that means about 370 or so to the flywheel...I guess 50HP more is not super unrealistic, but he was only guessing, and most people seem to guess a little high, say about 50 HP????

ArchangelX

LOL...ya.heh. I figure with my mods I'm doing 300 at the crank....290 at the wheels.

Mr rx-7 tt

iTrader: (5)

Those numbers are right on for a ported motor even at 15 psi with all the bolt ons.
420 BHP = 360 RWHP
I have seen plenty of cars at PFS and other shops that produce that number. Pettit claims 440 BHP in their cataloge. 440 BHP = 375 RWHP.

Rich Farrell made 368 RWHP @ 15 psi on the stock twins with a hi-flow cat. 368 RWHP=432 BHP.

If the motor isn't ported uping the boost to 17 psi will get you those numbers but the turbos won't last long and neither will the block and race fuel is a must at 17 psi.

Those numbers and the article are right on...

duboisr

My mechanic had the PFS-PMS purple and he said if he punched in 17 lbs and hit enter the number always came up 15 lbs. So can Farrell over ride the program ?

ttb

so did they mention if the motor was ported? i assume no, since you didn't mention it.

ArchangelX

I did mention it. That is...NOT streetported.

Mr. RX-7 TT, well..that's why I posted the article...cuz I'd like to know if it's true.

So you're saying that at 9psi...with all the bolt ons, a 7 is capable of putting out 320 horses at the crank?

I've been doing alotta reading about the HP gains from various mods...

Apparently tons of people have no idea what they're talking about. I've read tons of posts where people have been saying that 13psi is pushing it on the stock twins...or that 15 is as high as you want to go or 17 is as high as you can go.

Also..may posts saying that 400hp is not possible on the stock twins without a streetport.

And that hitting 320hp is going to take at least 12psi....this is just a small smattering of the opinions on this board.

https://www.rx7club.com/forum/showth...ighlight=320HP

https://www.rx7club.com/forum/showth...ighlight=400HP

https://www.rx7club.com/forum/showth...ighlight=400HP

https://www.rx7club.com/forum/showth...ighlight=400HP

https://www.rx7club.com/forum/showth...ighlight=400HP

If this is all true..then I'm going to stop reading so much damn shiat off the forum, cuz it's bad info.

Either way..320 at 9psi doesn't sound right to me..

https://www.rx7club.com/forum/showth...&highlight=320

So...let's just say..with my current mods..9's all around, what's the most reasonable RWHP at what PSI can I expect?

This is with good tuning by Ralph at Xcessive Motorsports(GZ)....

neevosh

I put down 271rwhp at 10psi with all the bolt ons and a stock cat. This was at a 11:1 AFR. And an engine with low compression. So I'd say that 320bhp at 9psi is definetaly possible.