Will Allen

Or go to southen NJ and drive on at PES.<ul><li><a href="http://vu.union.edu/~allenw">Will's A4 page</a></li></ul>

donp

Yep, they inject fuel into the cylinder and ignite it on the exhaust stroke when the valves are open to keep the exhaust energy up. Murder on the valves. Race car only stuff.

javier mirandes

Have you tested an S4 yet? If so, how does it compare to your PES 2.8? I heard (but not test drove) a friend's PES 2.8 and it was VERY noisy, both inside and out. Is this your experience as well?
javier
'00 S4 Imola this week

Bill D

Let me first clear the water on anti-lag...

Anti-lag isn't hard on the valves...in fact it cools the valves. It is extra hard on the turbos...and the turbos tend to be expensive....so it isn't always recomended for street cars...but there are measures that can be taken to avoid significant wear.

There are two types of anti lag...Both dump extra fuel into the exhaust manifold so that it ignites and keeps the turbo kicking. The best systems also add more air to the mix...dumping the blow off valve surge onto the exhaust manifolds. Mitsubishi Evo IV's-VI's come from the factory with mild anti-lag systems....as well as all the other really really cool things they come with which make the S4 wimper....of course I AM buying an S4.

The trick to saving longevity is to stay cool-headed with the anti lag. If it is only used when neccesary you will have no problems...if you have it set to keep the turbo at max boost 100% of the time (They CAN and DO) you will see reliability suffer. Small spikes in a turbo's operating temperature won't seriously accelerate wear...one continous huge plateau of VERY high operating temps will do damage...of course Evo VI's come with Titanium impellers that help reliability in the already understrained 20G turbo....(wimper S4 wimper).......

Another trick to keeping the turbos spooled between shifts is to keep from lifting all the way between shifts. If you lift to half throttle you'll still drop the revs without slaming the throttle shut.

Another item to consider is that I am told that Bosch blow off valves are NO GOOD. Almost everything from Bosch is good, but nobody is good at everything. This comes from a very very good source, so I'll probably be swapping those for something a little more consistent.

You will learn to love turbo lag.....Iove it...There are too many advantages to turbo charging...How could you not love it?....Learning to extract the ful potential from turbocharged cars is a delicate art....learn it...and you will be enlightened.

Keith

Read your post and couldn't agree more, I also have a 323GTX and a '94 RX7 R2. As you say, you get used to the power characteristics and learn to compensate for it. For me getting everything just right in a corner with a turbo car is even more satisfying then in a normally aspirated car, but it can be more challenging. The RX7 pretty much stays out of the wet conditions but the 4 wheel drive 323 thrives, thus the reason for a new S4.

Reed Merritt

Avram:

You are entirely right. Turbos are more dependent on the "demand" from the driver than where the engine is in the rpm range. The engine can be spinning in the higher rpm range and the turbos will be "coasting" (or "idling" for them) if you do not have your foot in it. They will then have to spool up before boost can be produced, producing the lag you mention. Unless you keep your foot in it constantly (almost impossible and bad for the turbos and the engine, not to mention the drivetrain), you ARE going to experience some lag. That is why automatics are somewhat better for turbo-charging than manuals. An instant downshift to a lower gear WITH your foot "in it" WILL cause a quicker spool-up of the turbos and less lag with an automatic vs. a manual.

Supercharging IS the answer to getting rid of lag, but at the HP and $ cost of driving the compressor mechanically. Boost IS instantaneous, though, and there is MUCH less heat produced.

There is also a possibility that the boost control valve was not working properly. Also, don't forget that you were driving a "green" engine with very tight tolerances, including in the compressor area. Since the turbines spin at over 100,000 rpm when producing boost, they might not be accelerating as quickly as they will once properly broken in. Remember, ALL bearing surfaces (both engine and turbos) must be broken in properly to perform up to specs. Drive that car again after 1,000 miles or so and see how it feels. I would bet that the lag has diminished somewhat if everthing else is operating properly.

Reed

Josh Pinkert

I think you're expecting too much here. In my opinion, you're asking for full power to be available instantly at any time. And I don't think you get that with any car. You, the driver, have to make adjustments to the dynamics of your engine.

Take, for instance, your Honda Del Sol. You have to be aware of the VTEC change-over point. If not, you're going to get a surprising surge in power around 5500 rpm (at least that's the way the Integra GS-R is). So you, as a driver, need to be aware of this characteristic.

Turbo cars: You have two complaints/problems. I'll address the second one first. There is a short lag between when you apply the accelerator and the desired amount of power is reached. What you really need to do is become familiar with that characteristic and how it applys to your car. You say you press the gas until you get the power you want...and then you have to back off, etc etc. And you have this constant need for adjustment. What if you had a better sense of how much power you'd ultimately get for any given amount of gas for any given gear? Well, then you'd push the pedal down the amount you *knew* you wanted and power is there 1/2 second later. There still may be lag, but familiarity with the car spell predictability. You don't roll the dice every time you give it gas...the car is just a machine. It is predictable...

Now the first problem...lack of power at lower rpms (I'm assuming you mean below 2000 rpm). What cars have you driven that are really strong below 2000 rpms? I don't know of many. Mostly large displacement cars. Certainly the VTEC motors don't have much power below 2000 rpms. And if your ultimate goal is the quickest launch, with most cars, you wouldn't be slipping the clutch below 2000 rpms. If you're talking about around town driving, I can't really provide a concrete answer (never driven the S4), but I would assume that the car is drivable below 2000 rpms...just like a VTEC car is.

Hope all this helps.

Jim De Arras

What will that do, besides wear the clutch and syncronizers?

KevinH

I had a worked up 300ZXTT and by watching the boost gauge you could tell when you were in negative, neutral, and positive boost. Eventually you can tell by the seat of the pants. You get used to it and know what you have to do to get the most performance out of the car. Don't get depressed about the "lag" problem, you'll get used to working around it.
Kev

DwayneC

I pretty much did all the above (including left foot braking at the track). Where you get stuck with your pants down is when you're lugging around town at 2500rpm and need to jump on the gas to avoid an "idiot". Here is where the boost controller comes into play. My car springs where before it thought about it then jumped. Can be hairy at times. On the highway, I never shift out of 5th. Its great.

Your milegae may vary as the K24 is a bit bigger than K03.

Dwayne
94 S4