Gt-p Gets Spanked

[Guest Mr Walker]

It may lose 9 out of 10 races to the auto as the auto will be way more consistent BUT the manual will post the FASTEST time.

If the manual loses 9 out of 10 races to the auto how can it post the quickest time?

Falchoon, I've read lots of your post and I've got plenty of time for you but are you seriously asking me that question?

How? Easy, on the tenth run, the manual will win and post the lowest ET!

Ie: Fastest - Geddit?

[ms700]

Look, the point I'm trying to make is that in the AU for example, no one raved about the auto XR6/XR8 being faster than the manual XR6/XR8 - why? 'Cos they're not! What's the difference now? Yeah, I know were talking about Turbos not N/A cars and that it stays spooled up blah, blah, blah but other than the shifter, how different is the auto and how much better is it in straight line performance than in the AU?

The main difference between AU's and BA's is the AU's were not turbocharged!

You see, the turbo'd BA auto has the ability of keeping the intake manifold pressurised 100% of the time, even during shifting.

Where a turbo manual can't, unless you flat change.

Therefore, the auto should be faster, because the intake manifold is always pressurised with the full 6psi or whatever the car runs, and the manual's turbo will have to re-pressurise the intake manifold after every gearchange, because the throttle body is closing.

If you have ever watched a boost gauge in a auto AND a manual, you will know what I am talking about.

If you would like a demonstration, come right over. I have a BA XR6T AUTO and a supercharged XC MANUAL.

[mickq]

Look, the point I'm trying to make is that in the AU for example, no one raved about the auto XR6/XR8 being faster than the manual XR6/XR8 - why?  'Cos they're not!  What's the difference now?  Yeah, I know were talking about Turbos not N/A cars and that it stays spooled up blah, blah, blah but other than the shifter, how different is the auto and how much better is it in straight line performance than in the AU?

The main difference between AU's and BA's is the AU's were not turbocharged!

You see, the turbo'd BA auto has the ability of keeping the intake manifold pressurised 100% of the time, even during shifting.

Where a turbo manual can't, unless you flat change.

Therefore, the auto should be faster, because the intake manifold is always pressurised with the full 6psi or whatever the car runs, and the manual's turbo will have to re-pressurise the intake manifold after every gearchange, because the throttle body is closing.

If you have ever watched a boost gauge in a auto AND a manual, you will know what I am talking about.

If you would like a demonstration, come right over. I have a BA XR6T AUTO and a supercharged XC MANUAL.

Actually there are a few alternatives that need considering.

As you pointed out, you can flat change. This keeps the engine on boost all the time. Easily done, just dont move your right foot while you change gear. (You obviously know that...others may not)

You can also modify your car and do a trick they use in rallying: put a small fuel injector in the exhuast manifold. The fuel explodes, and the turbo goes crazy. The turbo can be kept on boost 100% of the time, even near idle. that's the reason why rally cars can take off so fast and make that awesome popping sound out their exhaust. But most would consider that overkill on the road (but not necessarily so, as long as noone checks your pollution output!)

However in a manual when driving hard, I dont believe the difference is worth getting excited about. Simply because when near redline and changing to the next gear, the engine speed doesnt drop much and is still well and trully within powerband, meaning the moment you are in the new gear, the turbine blades are at normal operating speed anyway. Even less important in the XR6 because without the turbo the engine still puts out a fair bit of power. (Ask me how I know!)

Also, the example you give of your supercharged car doesnt hold. A supercharger has a direct physical connection to the engine (belt) whereas the turbo uses exhuast gas. In a supercharged vehicle, regardless of gear box type, the supercharger speed will always drop in exact proportion to the engine speed. So if an auto drops from 6000rpm to 4000rpm after it goes into the next gear, and a manual does the same, then the speed and output from the supercharger will be identical. Its quite similar (but not identical) for a turbo - just slightly less direct. Even in an auto the engine speed drops when changing gears because the next higher gear will be at lowe revs. Engine speed and load determines exhuast output. Exhaust output and load determines turbine speed. Turbine speed determines boost. (Until the wastegate says otherwise and dumps excess pressure).

Oh, and lets not forget another advantage of manuals: takeoff. You can select takeoff engine speed exactly on the edge of traction and get a much faster initial takeoff in a manual. Autos require you to stomp the brakes and accelerate at the same time (not good for the transmission), or rev it in neutral and shove it into drive (not good for the transmission either!) or put in a higher stall converter (not good for road use) to get anything like the same effect. Try racing off the line in a manual WRX vs an auto WRX and you will see the difference even more noticeably: one sling-shots off the line at warp speed. The other takes off in a leisurely manner and once the engine and the turbo spools up, goes quickly. (Too bad that me and my manual are across the intersection and in the right lane by then...)

Besides, being a purist, who the hell wants their power tranmitted to the wheels via liquid sloshing about in a container??!! The only liquid sloshing in a container that gets near my car is soapy water with a sponge floating around in it. Being someone who likes driving hard and driving to my and the cars limits, Id be embarrassed to have a torque converted in my car without a very good excuse.

Blades sloshing liquid about to push a vehicle along should be limited to boats....