No, not really. 0-60 as measured by G-Tech pro was 3.1 sec on 235 Bridgestone RE-11 street tires. (75 F day, 600' altitude,.. 12' roll-out in the G-Tech)

The bigger the turbos,. the slower the car. (At least on the street with a manual trans).

By the time the big turbo guys get into boost,.. they're at redline and have to shift,... They spend most of their time either off-boost,.. or fighting for traction. Meanwhile the Subaru is laying down 100% of it's power all the time and rocketing ahead.


Big turbos = great dyno numbers and great Texas mile speeds,... Small turbos = a quick street car that's a riot to drive.

You just gotta decide what you're goals are. To me,.. a loss of 400 rpm of spool isn't worth an extra 200 hp.

Another downside of the big turbos are that even though you only make power for 1/3 of the rpm band,.. you still have to build everything for that power. Engine, clutch, half-shafts, fuel system, tires, etc, etc, etc. Many cars end up being a royal pain to drive, needing a long warm-up, being a dog around town,.. heavy clutch,.. and they still get beat by a 280 WHP RX7 or a 350 whp Subaru.

 

We're not in a Honda/Subaru forum, not sure what you think a "big turbo" is on our platform. The "big turbos" on the car on this thread have 1 bar of boost by 3300 rpm and the car did 0-60 in 2.6 seconds.

 

Wow,.. I have never seen that. I've looked at a dozen or more dyno graphs,.. and all seem to have their torque-peak in the 4,000 to 4,500 rpm range. Teh graph in the first post in this thread for instance shows that the torque is in by 4,300 rpm. A full 800 rpm later than stock in 3rd gear. If that dyno graph was done in 4th or 5th,.. it' even later.

Who's car are you referring to? I'd like to know what he / she is running.

Is that in like 5th or 6th gear? Or are those turbos coming up that soon in 2nd or third? Auto or manual?

FWIW,. I was just using Subaru as an example,. because my first round of mods comes in 2 weeks on the 997 platform. With that Subaru,. there were no good turbos available on the market at any price,.. so I had to make my own. An acquaintance and I designed our own aero profile, and he cut a compressor wheel from billet in Honeywell / Garret's labs. (he used to work there),. then we mounted it on a Garret center section, clipped the turbine 4 deg., put a Tial SS hot-side on it,. and custom machined a 3" Mitsu compressor cover to fit the Garret center.

I am wanting to do something similar for this car,.. but the VTG complicates things. Perhaps just a lighter compressor wheel of similar aero-profile to improve shift-recovery? Or perhaps we unshroud the secondary blades?

I have seen many, many of these cars (mostly 996's) with 700 + hp kits on them,. and all were the same or slower on the street afterwards. But those were manual trans cars. With an automatic and brake boosting,.. the above doesn't apply of course.

 

you no saaaaay

 

Visualize your Subaru beating this big turbo 6 speed car 0-60

http://youtu.be/JKtOaRhqAfI

 

Please be sure to include the context,... On the street,.. manual trans.

(Obviously with an auto,.. that all goes out the window. Turbo selection is no longer critical,.. almost irrelevant even. You can brake-boost a turbo the size of a soccer ball with an auto trans.)

 

That car is an auto. Doesn't count.

Obviously with an auto trans (or a sequential with an ignition interrupter and a 2-step), at a standing mile event,... the bigger the turbos the better.

I didn't mean to start something,.. just pointing out that with a manual trans,.. turbo selection is critical. A loss of spool can rarely be made up with hp in your daily driving. Certainly if you drive far out of the city to find a deserted road, or trailer your car to the Texas Mile event and find an opportunity once in a while to put your foot down in a high gear and hold it there,.. but the price you pay is that in daily driving,. the turbos are hardly accessible. You end up driving what is essentially an N/A car with low compression.

In most platforms,.. the stock turbo is sized such that the boost-control system is holding the turbo back early on,... so you can step up one or two sizes on the turbo and the car gets faster with no perceptible loss in spool.

The stock turbos in the 997 platform already come up late,.. at 3,500 (in real terms. Obviously you can brake boost them up sooner,.. but that's not representative of the real world). And going from turbos that come up late at 3,500 to ones that come up even later at 4,300,... on an engine with a fairly low redline,... and you run the risk of having a car where it's an exercise in desperation trying to keep it on the boil.

 

The car is a 6 speed, it's sequential but thats irrelevant in his 0-60 as he doesn't shift until 60.
You make a lot of assumptions based on turbo size. You talk about a 700 rpm increase in spool and think that it's a loss of usable rpm range. A stock 997 redline is 6800 rpm, the car above is 9000 rpm. Do you think he has a wider or lesser boost rpm range? Putting a larger turbo, you're shifting your power band up, obviously you've made compensations for that in your big turbo build. Saying that anyone can beat a 1000 hp car with a 360 hp car because they have big turbos is very arrogant and going to get a reaction from everyone who knows better.

 

lol lets start over. whats a big turbo to you?

 

Very well then.

 

Its a tough audience on 6speed - welcome and look forward to hearing about your 997 mods

 

i want more 900hp kill stories in a 300hp Subaru.... forget 997 mods everyone here has those already ...

 

1000bhp Supra with a huge turbo, rwd and handles like its on stilts vs a suburu 4wd with 360 whp. Which do you think would win a street race with limited amount of road? I know if I was driving the supra it would be in a wall backwards before i finished the race lol

 

only way i see subaru winning is if that limited amount of road is covered with snow

 

Maybe. Much would depend on who's driving each car I guess.