A flashed K16 is faster than a flashed K24 ???
a V-Flow and Ruf exhaust doesn't make that much difference, does it???

 

If you compare oem K16 and K24, K24 is only a hair faster in 0-60, 0-100, and 1/4 runs.

 

I have turbo s cab flashed with exhaust and it seems like it's faster than the black car in the video. Maybe it's just because of the vid but I thought he would smoke the stock m5 and the yellow tt to be honest.

 

I thought the same too, but I've ran with another EVO chipped Turbo S. The outcome is similar. After all runs, I will say K16 is able to jump 1-2 car length from rolling start. The K24 start pickup speed after 220km/h. Just for you to compare, my K16 chipped TT ran dead even with stock 997TT from 60km/h to 250km/h.

 

very interesting, I don't have much seat time with a k16 car so I really was not able to compare basically just assumed the k24 would pull harder, good to see these vids.

 

I never got a chance to drive a K-16 set up but my current car bone stock tiptronic 996 Turbo S, I must admit lags big time. I don't feel my Turbos really kick in until I hit 4000-4500 RPM range. But when they do there comes the snap. Problem is the snap only last a second or two then the same deal with the next gear. My prior car bone stock 2003 X50 Tiptronic was even worst, eventhough my Turbo S performs better than my 03 X50 did, it is still not to my satisfaction. If I can only have my Turbos kick in with the same snap around 3000-3500 RPM range then I will be a very happy man.

 

I have K16 hybrids and there is absolutely no lag. I have not been in a super modded K24, but I have been in a S with K24's and the differencei in lag was much more. To me there was about 1200 rpm difference in where they both kicked in. But that was what I perceived only. I think for low end grunt, the K16 is way better and one of the best tuners out there recommends it....

 

Here is an interesting set of data that answers this question for me. This is from the Porsche-produced sales-information guide for the 997TT.

Here are the rpms where maximum torque is made:

996TT (k16): 2700-4600
996TT S (k24): 3500-4500
997TT: 1950-5000

Now obviously, k-24s make more torque so there's no guarantee that at 3000 rpms k-24s aren't making more torque.......but clearly there is a lag difference.

I'm really impressed by the 997TT curve........not enough to go out and buy one because the price difference is just silly for what more you get from it.

 

so maybe hybrid K16's are the answer.. well at least for a tiptronic

 

my K16/GT2 hybrids are producing incredible low end grunt.... way lower than what the std curve says, I think a lot of that is the zero clearence done to the hot side. Makes it way more efficient than the std turbine...

 

Can anyone else with a GT2, X50 or TurboS comment? Do you feel this lag the several people have mentioned. Seems odd that a $16K X50 upgrade somehow result in a slower car except over 150mph???

As 996TTSCAB said is it normal for these cars to only get to full boost only at 4500-5000rpm?

 

If you race stop light to stop light, the K16 turbo might be faster than a K24 based turbo for a few hundred feet only. But on the road, the k24 based tubos are faster. I quarter miled my K16/24's and k24/18G's extensively and by the 1/8 mile mark, the k24/18's are way ahead of the K16/24's. And 1/8 mile is only 660 feet. At the end of the 1/4 mile same thing - K24/18's are quicker ET and trapping higher. It depends what you want - I like the higher power of the K24/18G and I don't notice any more lag than with the K16/24.

 

John - does your 16/24 vs 24/18 analogy hold true for straight K16s vs K24s? i.e. is the supposed lag between 16/24 and 24/18 similar to what's between K16s and 24s? My car has K16s now .... really more or less satisfied with them, but thinking about just a little bit more power through the range. Might be juvenille, but I enjoy the turbo "punch" and figured this would be harder in a K24 turbo albeit maybe with the sacrifice of a few hundred rpm. I was a little surprised to hear some folks on here say that the lag might 1000rpm or more!

 

If you really want to know how these turbines compare, talk to Kevin at UMW. He's probably the most knowledgeable guy on german turbos. And He will tell you that there IS a noticeable/physical difference in lag.

I think the big question you need to ask yourself is how much power you want? If you are heading towards the stratosphere, I am sure Kevin would say K24 based turbos. But if you will cap at 600-700 whp, I'd bet money that he would steer you into K16 based turbos, because you get more torque and power under the curve. I have had several conversations with him about this. He has also stated that the there is very little difference on the turbine side, it is in the cmpressor side where the big difference lies. Again this is my memory and I do not want to put words in anyones mouth...

 

Dreamtripper,

I am not sure as I have only used k16, K16/24 and K24/18G. The K16/24's lag a little more than the straigt K16. The K24/18G's are about the same as the K16/24's I had, but I added a fuel system and custom tune with the 24/18's, so that may be helping the 24/18's a bit. IMO, there is way too much emphasis on lag regarding the k16 vs. k24. When you are driving the car hard and you want max acelleration, the kick from the larger turbos is welcomed. The K16's just do not have it up top and at full throttle, high RPM shifting, you are right in the sweet spot of the larger turbos, so there is no lag. IMO, when you drive hard, you are beyond the area of the curve where the K16 spool quickly, so it is sort of wasted response. It is more useful to have your power higher in the rev band, where you can take advantage of it.