Here is an interesting comparison. You have two turbos the first is the K16/24g from KPG and the second is the K24/18g from JohnD. I apologize to both members if they did not want these sheets being posted, but since they have been posted in the past, I felt it would be ok to show case in point. Which is power under the curve. Both cars are set up at near identical Hp levels. Look at the difference in the torque and power bands. The K16's come on with 400 ft-lbs of torque at 3000 rpm, while the k24's don't hit that until 3700 rpm. Also look at how much flatter both the hp and torque curves are. Way better power distribution all the way around.

I think most anyone will agree that power under the curve is more important than just peak numbers. In other words two cars at the same peak power levels will not run the same if one has a much fatter curve that allows much more flexibility in the rpm range. Call it lag or whatever, but more power at lower rpms is better given the same peak power numbers.

K16/24g


K24/18g

 

Find someone near you with an x50 and feel the differences. You are welcome to take my stock x50 for a spin and feel it for yourself.

To me the x50 gives you a little bit more lag and a little bit more punch and makes the "turbo" experience complete. When I drove the base car, the power delivery was smoother. But I didn't quite feel the kick that makes the drivers and passengers go wow.

 

it's fine to compare stock turbos if your going to remain stock, otherwise, it is irrelevant. The rush is from lag to power, while the 16 is smooth all the way through. 24 hp doesn't make that much difference...

for the price difference of an x50 you can build a std 996tt to put out 100-200 hp more easy with k16's.

 

The only way to compare turbo to turbo is to keep all other variables constant...
you guys are posting dyno sheets from different tuners with different cars and and different setups and only taking into consideration the turbos in question. I am no statastician but this is a pointless arguement.
Take one tuner and have him put on the same car the turbos in question .. run dyno numbers on the same day.... keeing everything constant... that will give us an unbiased apples to apples conparison... otherwise we have a A person who has K24s running some tune... who knows at waht boost and what other add ons... and another person running K16s who who knows what tuner with XXX add ons.. pointless...

I have seen a stock K16 run 11s... and I have seem a stock K24 run 10s.... but those are the excpetions... what say you... does that mean every K16 stock flashed car will run 11s? and and every K24 /flash ect run 10s? hell no...

just my opinion...
markski

 

As a foot note: The K24/18G dyno I posted was done at Approx. 100 degrees and extremely high humidity (as bad as it gets) - the worst possible conditions. Here is a much, much better comparison - best 1/4 pass with each set-up with about 20 runs with each set-up at the same track with similar temp and conditions, so these are the best times that each turo is capable of on my car with me driving. The 1/8 mile ET, 1/4 mile ET and trap speed tell the whole story - clearly the k24/18G's at going much faster at 660' and do not give anything up after that. See here:

K24/18G time slip:



K16/24 low clearance Hybrid time slip:

 

When I bought my car it was k16...I flashed it and installed a remus exhaust as well as a BMC air filter...The car was fine,no lag,instant power but after 5000rpm i did not have the power I wanted...if i raced another car and shifted to redline,next gear was engaged about 4800rpm so no great power...On th eother hand cruising with 6th gear was awesome...instant torque from 2800rpm...then i switched to k16/24 and reflashed the car...Above 5000rpm the car was almost the same...no significant difference...but from 2500 to 5000rpm...wow...6th gear was like 5th with k16s...and remember,i only switched the turbos...Amazing torque and no lag at all...instant power...However still in a race the power was not great over 5000rpm...i remember mark always saying k16 dies at high rpm...and of course he was right(he always is).So as ageneral rule if power at high rpm is needed k24 is the way to go...Now i switched over to k24/18gs and 60;b injectors but still have not finish fine tuning...hopefully next days i will post results for comparison...

 

It just seems like some cars run faster and or are "healthy" vs others.... we have seem 18gs with a 5 bar , exhaust, etc run 10.8s at 133 mph all day long... yet others with a full 18g upgade cant even break 130s...
Same goes for 24s as well as K16s... we have seem Scott run 126 mph on a K16 stock with a flash.... etc.... Yet I couldnt break 126 on my K24s...
so again, comparing dynos and 1/4 slips just doesnt really prove anything other then what "your" car ran and or dyned on that particular day.... It does not prove what a similar car with similar set up "should" run... or better yet - what it should have ran....

Other example,
My car first time out with 35rs trapped only 142 mph... yet it now trapped 149 mph on same gt35rs... same boost, different clutch, same track, driver, and Temps...
I gained 6 mph just by babysitting the car ... yet someone may think that I HAd to put on Bigger turbos... I did gain 6 mph.... but I did not...

I can go on and on with such examples only prove that there is a lot more that goes into a fast healthy car then a set of turbos....
markski

 

So nothing proven here which shows that you can run hard with either K16's or K24's, but just like the top end usually belongs to the K24's, the low end always belongs to the K16's.

However, my K16 hybrids will sail to 7400 rpm like they have external help. So I don't have the loss in power mentioned above, but then again, I would not be surprised (in fact I'd bet on it) that my K16/GT2 hybrids with ZC will outperform a K24/18-20G. I have the low end grunt and the top end.

It would be nice to see exact comparos with everything being equal on the same car except for the turbos, but who would waste the time and money to do this....

 

Mark,

For the record, I believe my K16/24 1/4 mile time is the fastest documented/known time for the k16/24turbos, but my K24/18G time is not the fastest known time for that turbo, so I think it is safe to say thet the k16/24 can not compete with the K24/18G. Look at DMaffo's time on K24'18's..A K16/24 has not even come remotely close to that time. Personally, I do not think it is very likely - I hate to use the word "impossible"...

 

I just hate comparing and benchracing... so Im just trying to keep things in perspective.... we have seem miracle runs... etc... but Im sure it has a lot more to do with other variables then just pure turbos...
There are no miracle "turbos" as far as Im concerned.... and I had K16s,K24s, ZC stage 5s, garret GT35rs, and soon custom Gt35rs... I drove a full K24/20g a year ago including a few 18gs as well...
I have seem a 18g "healthy" trap 133 mph as well as others with a full 18g set up only trap 127 mph.... way too many things play into real factual data that its really impossible to deduce which set up is "better"....
mark

 

your time is a good time, but there are two people on the board that have run around the same time on stock K16's. Again, showing that a drag race is as much about skill as it is about the engine. So I would not make a conclusive statement such as you did.

Autoaddictions ran it in 11.44 with stock K16's and Jimmer ran it in 11.59 with stock K16's. And I'd be willing to bet that there are several more that ran even faster with K16 hybrids.

 

People strip cars, use drag radials, remove components to save weight, etc. so comparing to others times is not the best analogy. That said, let me rephrase it a little, - the point that I am trying to make is that my same car, with my consistent ability and after many, many passes did those numbers as a "best I could do" with each turbo. The K24/18G's - all other things being somewhat equal, after many passes on many different days were faster on every pass they ever made compared to any of my K16/24 passes. They are definetely faster on my car in a direct comparison. My car would never come close to trapping 130 with the K16/24's, yet trapped between 131 and 133 on every pass ever made with the K24/18G's. The K16/24's only trapped 127 once and 125-126 the rest of the time. From my experience of using both turbos, the 24/18's were faster to 1/8 mile every time, faster to 1000' every time, faster to 1/4 mile every time and trapped higher every time. We are talking over 50 passes...and the K16/24's never even came close once. personally, I am convinced the 24/18G is a faster turbo. You are welcome to your opinion if you think the K16/24's are as fast or faster, but you will never convince me having owned both and having tracked both extensively.

 

Very eloquently put, John. Hard to argue with that ...although someone will find a way

 

Nope no argument there. No one ever said that the K24 could not produce more power at the top end. Everything else being equal it will. But you do not live at the top end of an rpm range and most of your driving will be in the mid range. So in the end the K16 has more driveability and more torque in the low ranges and less power at the top end and less lag. The power with a K16 comes on smooth, there is no all of a suden surge like you feel with the K24. So you can continue to believe there is no lag difference when there conclusively is.

How eloquently put is that?

 

I'm going to have to disagree with you as well. Since I've had both turbos in question (k16/24, k24/18g), I have to say that the k24/18g's outperform the k16/24's in every single way. The onset of boost isn't even much different, maybe 300 rpms at the most, but once they both come on boost, it's game over. The k24/18g is truly an awesome turbo which pulls and pulls and doesn't quit.

When I had the k16/24's, I thought they were the best turbo available. They produced a lot of power down low and up high, and I thought my car was really fast. I was almost a little skeptical that the k24/18g's could outperform them, but I was completely wrong. The car is now MUCH faster than it was with the k16/24's and I'm much happier with it.