Jump to content
SAU Community

Recommended Posts

Hi all... i have conducted a TRUE comparison between the two turbos thanks to Sonic Performance and Garage 7. By true comparison i mean the only thing changed was the turbo. nothing else was touched. The result was suprising and disappointing both at the same time. We found that the GTX version DID spool quicker and hence started making torque and power earlier in the midrange. i now have FULL boost around the 3500 rpm mark which for a turbo like that is impressive. Its highly streetable!

The downside is that for the same boost level peak power is changed by .1 of a kw! its pretty much lineball! the two turbos match each other on the graph pretty much spot on.

runs were done with air temp probe and same correction mode and dyno that STatus uses for real world comparison.

Heres the pics.

Solid pink line is GTX, thin red line is GT.

p1020473s.jpg

p1020471v.jpg

  • Replies 101
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

Question:, is running the GTX at the same boost pressure as the other turbo a true 'fair' comparison? I mean... for example if your comparing a gt2871 with a gt4088 you don't leave them at the same boost.

It's interesting to see it ramp hard @ 3500rpm.

And then @ 4000rpm the GTX suddenly stops making power almost as if it's hitting surge. Was that just a case of the tune?

(ie back to back test, no tune adjust?)

Also interesting that its more responsive when other results all seem to show the opposite thus far.

Question:, is running the GTX at the same boost pressure as the other turbo a true 'fair' comparison? I mean... for example if your comparing a gt2871 with a gt4088 you don't leave them at the same boost.

what do you want me to do? run less or more boost?

i feel same boost level should give a truer comparison yes?

Lithium: no tuning.. was just run up. Declan ran out of time on the dyno but the AFR's were the same as before so its still fine.

It's interesting to see it ramp hard @ 3500rpm.

And then @ 4000rpm the GTX suddenly stops making power almost as if it's hitting surge. Was that just a case of the tune?

(ie back to back test, no tune adjust?)

Also interesting that its more responsive when other results all seem to show the opposite thus far.

yeah it probably needs a degree or two added in one part of the map to bring it back inline. this could be due to different airflow charactoristics of the two turbos.

i have seen other peoples results.. but they often have changed other things in their set ups which couldn potentially cause issues. as i said mine is a back to back. use the info as you please.

If the new turbo can flow more than the old one then potentially without raising the boost and/or adjusting the tune to maximize the new found goodness then potentially not really telling of the real difference. That result suggests to me the old turbo had more on it too...

If it didnt nose over hard, it would be looking to pickup a solid ~40kw @ 4500rpm.

Now that would be very interesting indeed.

Good to see a 18psi comparo too where most comparo's have been on 20-24psi for the most part.

Perhaps with more boost the differential between the two would be more noticeable.

Its a good comparison in that most cars are probably only going to run around this level of boost but this result is exactly what I would expect - apart from earlier spool. If you had of reved it to 7500rpm you may have actually seen some results.

I just dont know why you guys are so dissapointed - you only need to compare the compressor maps to see that there are f**k all gains unless your running around 2bar of boost with the gtx.

PS what type of engine management?

Been waiting for this.....the next step is to tune/map for the GTX but don't lift the boost. I reckon the ramp up will likely maintain its margin over the GT a bit better throughout the rev range . But I have a sneaking suspicion that the peak power [for 18psi] will be very similar.

But the GTX would be a lively package on the street, an extra 30rwkw at 3500!!! I'm almost tempted to sell my GT and try one [but I have other plans involving a dirty 30, so this challenge is not for me].

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • The sodium acetate, mixed with citric acid, doesn't actually buffer each other. Interestingly though, if you used Sodium Acetate, and acetic acid, THAT becomes a buffer solution. Additionally, a weak acid that can attack a metal, is still a weak acid that can attack a metal. If you don't neutralise it, and wash it off, it's going to be able to keep attacking. It works the same way when battery acid dries, get that stuff somewhere, and then it gets wet, and off it goes again breaking things down. There's a reason why people prefer a weak acid, and it's because they want TIME to be able to be on their side. IE, DIY guys are happy to leave some mild steel in vinegar for 24 hours to get mill scale off. However, if you want to do it chemically in industry, you grab the muriatic acid. If you want to do it quicker at home, go for the acetic acid if you don't want muriatic around. At the end of the day, look at the above thumbnail, as it proves what I said in the earlier post, you can clean that fuel tank up all you want with the solution, but the rust that has now been removed was once the metal of the fuel tank. So how thin in spots is your fuel tank getting? If the magazine on the left, is the actual same magazine as on the right, you'll notice it even introduces more holes... Well, rust removal in general actually does that. The fuel tank isn't very thick. So, I'll state again, look to replace the tank, replace the fuel hanger, and pump, work out how the rust and shit is making it past the fuel filter, and getting into the injectors. That is the real problem. If the fuel filter were doing its job, the injectors wouldn't be blocked.
    • Despite having minimal clothing because of the hot weather right now, I did have rubber gloves and safety glasses on just in-case for most of the time. Yes, I was scrubbing with my gloves on before, but brushing with a brush removes the remaining rust. To neutralize, I was thinking distilled water and baking soda, or do you think that would be overkill?
    • You can probably scrub the rust with a toothbrush or something. After you get the rust off flush well with water to neutralize and you will probably want to also use a fuel tank sealer to keep it from rusting again.
    • The sodium citrate solution is designed to buffer the citric acid to keep it from attacking metal quite so much, the guy that came up with that recipe did a ton of testing on how much metal loss occurs over time and it's nothing crazy unless you forget about it for months:   
    • Ohhh I see lol To be honest the main reason why I wanted to start modding is because of a business trip to Japan and Indonesia. I saw many cool and modded cars all throughout in these countries, especially Japan. I myself am of Chinese+Japanese nationality and when living in china (never lived in Japan js my dad side lol) I remember staring at these cars pass by with their loud tacky exhausts and insane wide body kits. And when I went back to Japan, I got even more invested even asking people about their cars and why they modded. Most gave similar answers to what you said but funny enough one guy just said that he saw the need for speed movie being filmed once in Tokyo I think near Shibuya Crossing and got inspired to tune and mod. After that I just started to fantasize on owning a car like that. Also tbh I prefer the R32 over the R34 it's just the R34 is more iconic lol (also apparently better aftermarket support than the R32) and my only goal really is just to make the car mine and make it fun to drive. As much as I love my Cayenne it's pretty bland to drive. Sure the interior is nice and pretty, gives you attention yada yada but I've wanted to experience what it is like to have a car that is truly yours. I suppose thats the goal so far. Haha if you find where I'm from, then sure. Ill help you out on your next "financial decision"
×
×
  • Create New...