2554R vs 2560R spool, lag, and response data
 

Hey all,

I have searched and search but come up short. I am looking for some solid 1.8 (any variation) data on not just peak power but mostly under the curve info on how these two turbos compare against each other. I am building my car to really be focused on AutoX but plan to visit tracks more and more over the next few years. Engine is not currently built but it's definitely on the radar as well. I had experience in a previous motor with a Pulsar 2860R and I liked the response over an old non ball bearing churbo so I think I just want to really improve on that.

If I had to make a power goal for now, it's tough because I think 230-240 would be enough but depending on the response differences, I wouldn't mind having the option for more power when desired as well.

Other note: I most likely plan to go higher compression on the build with e85 only for maximum response but that data isn't really needed since I know it will improve response. IF someone has solid data on a high compression 2554/2560 turbo build I would realllly love to see it!

Any solid factual data would be highly appreciated.

Thanks a ton!

multiple examples here
https://www.miataturbo.net/diy-turbo...ol-data-26641/

Let me clarify, I am not only looking for low RPM to high pull. I am curious on the difference between 0-full boost response at higher RPMs. Where do they fall off compared to each other. I am looking for more depth than just a dyno pull worth of data.

I asked ChatGPT to compare your question that's been asked 1000 times on two 30 yr old turbos:
"The Garrett GT2554R and GT2560R are both popular turbochargers known for their performance. In terms of spool characteristics:
1. GT2554R: This turbocharger generally spools up quicker due to its smaller turbine and compressor wheel. It's ideal for smaller displacement engines and applications where low-end torque and response are crucial.
2. GT2560R: With a slightly larger compressor and turbine wheel, the GT2560R may have a slightly later spool compared to the GT2554R, but it offers higher top-end power potential. It's well-suited for applications where high horsepower is the priority, and it still provides good response, albeit not as quick as the GT2554R."

But seriously the 2554 is way too small if you plan to build the motor. Corky and Keith Tanner have spoke about both setups back-to-back in a lot of threads.

Yeah, I don't have firsthand experience with a 2554, but can't imagine it having any worthwhile advantage over a 2560 on a 1.8. Even with the stock motor on a 2560, my car would make full boost just about instantly at any rpm I find myself at on track. I know not what this "turbo lag" is that people speak of.

I suppose if you don't like downshifting to pass people on the freeway, the 2554 might give you full boost marginally quicker. It'll also be in the danger zone as far as far as efficiency and turbine rpm go on track at higher power levels.

Again, biased here, but having run this setup for over a year I've never once thought about needing more spool.

This is really insightful considering I want to go E85 with higher compression. Early instant spool is the goal for AutoX with some track time. Some people I have talked with have said just go super charger and, sure that might be a better decision. I already have a turbo system ready to throw back in, I just need to replace my Pulsar 2860RS with something smaller.

Thanks a ton for this info!

I had a gtx2860r gen 2 on an 8.5cr built motor. The turbo sounds were intoxicating and spool/lag was no different than my old gt2560.

Personal opinion here, but there's a lot of dependence on the electronic boost control as well as your exhaust system, etc. when it comes to the physical sensation of boost (increased engine torque). I've been running at GT2560R in my street car for about two years now with fairly mild compression (about 9.0:1) and 93 octane. If you run the right fuel in combination with the right mechanical build and tune, I have the feeling you'll be pleased with the GT2560R. For extra obnoxiousness, see if you can find one with an anti-surge compressor housing...