k24/18g vs Garretts
#91
05-11-2008, 04:07 PM
Sean- K24 turbine housing > in size than the K16 turbine housing. The GT28s have a K16 turbine housing, and it is actually modified so that the exducer diameter (exit hole) has a smaller diameter than stock K16.
Scott- I was not making any comparisons to any other turbos. Just saying where I thought the GT28s excell. You can read my other posts to see my enthusiasm for other turbos, especially K24/18Gs. Every turbo fills a niche, and it is not always about performance but sometimes cost.
Scott- I was not making any comparisons to any other turbos. Just saying where I thought the GT28s excell. You can read my other posts to see my enthusiasm for other turbos, especially K24/18Gs. Every turbo fills a niche, and it is not always about performance but sometimes cost.
I think that a lot of people like to generically state that the K28's have less lag, but the K24/18's make more power. My point was that I don't know if that's necessarily the case with all setups.
#92
05-11-2008, 04:59 PM
Sean- K24 turbine housing > in size than the K16 turbine housing. The GT28s have a K16 turbine housing, and it is actually modified so that the exducer diameter (exit hole) has a smaller diameter than stock K16.
Scott- I was not making any comparisons to any other turbos. Just saying where I thought the GT28s excell. You can read my other posts to see my enthusiasm for other turbos, especially K24/18Gs. Every turbo fills a niche, and it is not always about performance but sometimes cost.
Scott- I was not making any comparisons to any other turbos. Just saying where I thought the GT28s excell. You can read my other posts to see my enthusiasm for other turbos, especially K24/18Gs. Every turbo fills a niche, and it is not always about performance but sometimes cost.
Scott, are you comming out for the Tx Mile?
#93
05-11-2008, 07:03 PM
So the bottom line is that gt 28s are smaller than the k 24ers and produce less power!!!! I always thought that the 28s were biger than 24ers and produced much more power i guess i was wrong.
#94
05-11-2008, 07:13 PM
lenny,
GT 28's produce way more power than stock K 24's. And they spool WAY faster. Also, they are ball bearing and don't require a cool down. They are overall a higher tech design.
GT 28's produce way more power than stock K 24's. And they spool WAY faster. Also, they are ball bearing and don't require a cool down. They are overall a higher tech design.
#95
05-11-2008, 07:14 PM
The GT28/GT700 hybrids are perfect for those wanting instant torque/boost response. They are a wet dream for autocross or launching from a standstill, yet are versatile enough to provide excellent top end performance, enough to satisfy most people. Sean, you aren't most people (
) and have an addiction for power that rivals your addiciton for sex (
) and painful songwriting. Upgrading compressors may net you a little more power and $800 is cheap power so it's a viable option. But be aware of the limits. There will be disparity between the larger upgraded compressor wheel and the current turbine wheel which may increase compressor surge. That turbine is really a limiting factor as it does not have great top end flow. Even if you had the turbine housing modified to hold a larger (even clipped) turbine wheel, the turbine housing is small (total size and A/R). Hell, you could easily swap in complete GT30 or GT35 CHRA with both wheels with slight modification of your existing turbine housing, but the housing is such a bottle neck you would not realize the potential of the larger wheels. I do not want to discourage you from upgrading your GT700s...there is room for improvement and that ceiling might provide the additional power you crave for little cost. It would be blazing a new trail and there is great satisfaction (ie, bragging rights) in that. But if you want to make siginificantly more power and have any plans on building your engine (rods) then you might as well put in a little more $$ and jump to bigger units (K24/18G, K24/20G, GT30 or GT35). Just my thoughts. Having said all that, I would like to see how far you can take the GT700s. I would love to eat my words. 
) and have an addiction for power that rivals your addiciton for sex () and painful songwriting. Upgrading compressors may net you a little more power and $800 is cheap power so it's a viable option. But be aware of the limits. There will be disparity between the larger upgraded compressor wheel and the current turbine wheel which may increase compressor surge. That turbine is really a limiting factor as it does not have great top end flow. Even if you had the turbine housing modified to hold a larger (even clipped) turbine wheel, the turbine housing is small (total size and A/R). Hell, you could easily swap in complete GT30 or GT35 CHRA with both wheels with slight modification of your existing turbine housing, but the housing is such a bottle neck you would not realize the potential of the larger wheels. I do not want to discourage you from upgrading your GT700s...there is room for improvement and that ceiling might provide the additional power you crave for little cost. It would be blazing a new trail and there is great satisfaction (ie, bragging rights) in that. But if you want to make siginificantly more power and have any plans on building your engine (rods) then you might as well put in a little more $$ and jump to bigger units (K24/18G, K24/20G, GT30 or GT35). Just my thoughts. Having said all that, I would like to see how far you can take the GT700s. I would love to eat my words.
#96
05-11-2008, 08:02 PM
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), the GT28s should have the fastest spoolup since they have a BB CHRA and the smallest compressor and turbines of the three. On the K24/18Gs, both wheels are larger but the rotating mass might be lighter and the turbine housing flows better (and I am not positive but I suspect Todd massages the turbine blades a bit). This, plus the important fact that Todd just knows how to make these babies sing with his tuning, is why so many people deny they have any lag.
Garrett GT30s have the largest wheels BUT they also have BB CHRA and usually are accompanied by high flow headers and high flow exhaust without cats which all aids with spoolup.
Then there is Powell's setup...he has GT30 hybrids which use a K24 turbine housing. I have no idea how they compare to a true Garrett GT30 with Garrett turbine housing, but these bigger turbos will usually have more lag unless considerable mods are made in the rest of the system to reduce it. Powell posted initially that his GT30 hybrids were laggy but this statement was just after his car had just been competed and he came from K16 stage two.
Soon enough we will see a real world comparison between them here in Houston.
#97
05-11-2008, 08:16 PM
Theoretically (just postulating Scott ), the GT28s should have the fastest spoolup since they have a BB CHRA and the smallest compressor and turbines of the three.
On the K24/18Gs, both wheels are larger but the rotating mass might be lighter and the turbine housing flows better (and I am not positive but I suspect Todd massages the turbine blades a bit). This, plus the important fact that Todd just knows how to make these babies sing with his tuning, is why so many people deny they have any lag.
Garrett GT30s have the largest wheels BUT they also have BB CHRA and usually are accompanied by high flow headers and high flow exhaust without cats which all aids with spoolup.
Then there is Powell's setup...he has GT30 hybrids which use a K24 turbine housing. I have no idea how they compare to a true Garrett GT30 with Garrett turbine housing, but these bigger turbos will usually have more lag unless considerable mods are made in the rest of the system to reduce it. Powell posted initially that his GT30 hybrids were laggy but this statement was just after his car had just been competed and he came from K16 stage two.
Soon enough we will see a real world comparison between them here in Houston.
), the GT28s should have the fastest spoolup since they have a BB CHRA and the smallest compressor and turbines of the three. On the K24/18Gs, both wheels are larger but the rotating mass might be lighter and the turbine housing flows better (and I am not positive but I suspect Todd massages the turbine blades a bit). This, plus the important fact that Todd just knows how to make these babies sing with his tuning, is why so many people deny they have any lag.
Garrett GT30s have the largest wheels BUT they also have BB CHRA and usually are accompanied by high flow headers and high flow exhaust without cats which all aids with spoolup.
Then there is Powell's setup...he has GT30 hybrids which use a K24 turbine housing. I have no idea how they compare to a true Garrett GT30 with Garrett turbine housing, but these bigger turbos will usually have more lag unless considerable mods are made in the rest of the system to reduce it. Powell posted initially that his GT30 hybrids were laggy but this statement was just after his car had just been competed and he came from K16 stage two.
Soon enough we will see a real world comparison between them here in Houston.
#98
05-11-2008, 08:35 PM
And how about gt28s compared to k24/18 or k24/20 what is the power difrences? What i am realy asking is if someone has a certain set up lets sat fuell system,flash,headers, IC,100 cell cats, air intake and they were to put these k24/18 or k24/20 or the gt28s what would you think the overall outcome in power and lag would be? which set up would out perform the other. I know that not an easy question. I was just wondring!!!!
#99
05-11-2008, 08:45 PM
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at wAnd how about gt28s compared to k24/18 or k24/20 what is the power difrences? What i am realy asking is if someone has a certain set up lets sat fuell system,flash,headers, IC,100 cell cats, air intake and they were to put these k24/18 or k24/20 or the gt28s whould you think the overall outcome in power and lag would be? which set up would out perform the other. I know that not an easy question. I was just wondring!!!!
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#100
05-11-2008, 08:58 PM
What I can tell you from real world experience is that the Gt 28's hit faster but the 24/18's definitely have more up top. The empirical facts layed out by Chris are reflected in actual application.
#102
05-12-2008, 11:01 AM
I see that theres no 'free lunch' with turbos, bigger ones produce a higher HP as they can flow more air or the same air at a lower temperature (i.e efficency band is higher up the scale) but spool up slower.
It depends what rpm range you mostly drive in to get the most out of it... I know that you can make a turbo more efficent with closer specs but with Kxx vs Garretts... techincally Garretts are ball bearing and create less friction and techincally what you can do to a K unit you should be able to do to a garrett. Correct me if im wrong tho!
Another point is you can get hold of the compressor maps for garretts and choose the EXACT one for your needs but ive never been able to see a Kxx hybrid map.
I also see many of big dogs run GT35s...
It depends what rpm range you mostly drive in to get the most out of it... I know that you can make a turbo more efficent with closer specs but with Kxx vs Garretts... techincally Garretts are ball bearing and create less friction and techincally what you can do to a K unit you should be able to do to a garrett. Correct me if im wrong tho!
Another point is you can get hold of the compressor maps for garretts and choose the EXACT one for your needs but ive never been able to see a Kxx hybrid map.
I also see many of big dogs run GT35s...
#103
05-12-2008, 01:49 PM
I am in the car videoing
www.youtube.com/watch?v=Vn2IDGpx-vE
You can see The Parasol pulling at the top of 4th.
www.youtube.com/watch?v=Vn2IDGpx-vE
You can see The Parasol pulling at the top of 4th.
#105
05-12-2008, 02:41 PM
YES...
But...as Sean has seen I can tell Paulie will start to pull slightly (though not nearly as bad as Sean getting his *** handed to him
) at the top of 4th because of the extra HP he has on me. j/k Sean...you were handicapped I can tell that Paulies set up just doesn't want to stop pulling...!! I would love to see me, Paulie, Sean and Chris make a trip to Mexico on PUMP (93oct) gas to see how it all plays out at the top of 5th (or 6th for the P-cars)...
1st one to 200 wins...!!!