[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: K24 finally installed in 1986 5000cstq
Gary,
I'm sure the K24 vs K26 is going to behave differently on my 4000Q with a
modified MC-2 high-compression motor than on a '90 200 with a stock MC-2.
My 4000Q has a large single pass intercooler (944T), very short tracts from
the turbo to intercooler to intake, a mild cam, 2-piece EM, bypass valve
etc, plus it weights close to 700 lbs less than the 200 and has lower final
drive. Maximum boost is around 13psi, though I saw a little higher at sea
level.
With the stock K24, my 4000 had no lag, but also didn't pull very well above
4000rpm (with its gearing and 22.7" tires, this translates to 80mph in 5th
gear). On the track, high water and exhaust temps, heat soaking, etc was
common. With a stock K26, it has a little lag below 3500 but pulls great
above that and runs cooler at the track (rarely drive this car below 3000rpm
anyway). The lag is nowhere near as bad as my 5000Q was with its K26. Most
of my driving is done above 5000ft, where turbos spool slower anyway. At sea
level, eg Road America, it had almost no perceptible lag and pulled stronger
than modified S4's out of the corners.(A RS2 turbo might even work with this
car at sea level).
As with any turbo quattro, off-the-line acceleration is not the car's forte
-- AWD, some turbo lag and the need to shift to 3rd(I think I hit the rev
limiter in 2nd at under 55) conspire against it. The K24 was easier to
launch off the line for 0-60 runs, though I never timed it, and didn't
really care. On the highway and especially on the racetrack, the K26 is much
more powerful. I estimate 260-270 horsepower, with over 300 realistic if we
cranked the boost up to 18psi. (Warnings from experts on the list about
boost controllers and running this much boost at high altitude have kept me
from doing this so far.)
But, again , the K24 on a 5000TQ with only chip/spring, works fantastic!
Smoother, quicker, better throttle response, etc. It sure was fun in a foot
of fresh snow this morning!
No hard data for you, only seat-of-the-pants driving impressions and much
faster track times. Sorry for the long winded response, but since you
asked...
Gary Kaklikian
86 4kcstq
86 5kcstq
-----Original Message-----
From: Lewis, Gary M [mailto:Gary.Lewis@West.Boeing.com]
Sent: Monday, November 22, 1999 10:04 AM
To: quattro@audifans.com; 'Eric_R_Kissell@email.whirlpool.com'
Subject: RE: K24 finally installed in 1986 5000cstq
Eric said:
> On 11-18-99 "Kaklikian, Gary" Gary.Kaklikian@Compaq.com wrote: >
> >We just put the K24 from my 4000 on my '86 5000, which is stock except
> for
> >TAP chip, wg spring, and bypass valve. I agree - what a great improvement
> in
> >low-end, midrange, smoothness, throttle response, etc! Seems like a new
> car!
> >Conversely, the K26 works MUCH better on my 4000 (dual knock sensor
> >high-compression motor) than the K24 did.
>
> My engineering nature wants to understand why there is a difference in
> bahavior for the k24 vs. k26 turbos with the MC-1 vs. MC-2 engines.
>
> The lower compression ratio, single knock sensor (MC-1) benefits from
> quicker spool up using the k24 in place of the k26. I have not
> experienced any downside from using a k24 in my 5000cstq (MC-1) at 1.8
> bar maximum boost.
>
> What performance characteristics improve when using the k26 in place of
> the
> k24 in the dual knock sensor, high-compression motor (MC-2)?
>
> Does the higher compression ratio of the MC-2 produce hotter exhaust
> gasses
> that possess more energy to spool up the k26 sooner than the MC-1 can?
>
> What does the boost vs. rpm data look like for the various engine/turbo
> combinations?
>
Did anyone answer the K24 vs. K26 in a MAC-14/MC-2 car?? As I now have the
latter, I was curious. I'm having delusions of 2.2 bar, single pass I/C,
2-piece EM, and a stock RS2 turbo on my 1990 tqa (or saying screw it and
buying a 1991tqa...).
> Gary M. Lewis
> 1990 200tqa Silver/Platinum 146km 1.8 bar P6000 SVR, Bilsteins, BPV
> 1986 5kcstqa Sapphire/Platinum 180km Stock
>