28rs or 2871

[Remmy]

Last ride of the season I toasted the bearing in my 2860 with the larger hotside (.86 I think). Looking for a replacement and have found a pretty good price on another 2860rs but would really like to try a 2871.

Who has run both and what would you recommend? Should I coin up for the 2871? This is on a built motor running an Alpine kit (Apex) Any feedback appreciated.

CR

 

[HYFLYR]

you better make up your mind soon, snow is coming

 

[Remmy]

Any specs on a 2871 would be good to hear as well? (.64 A/R housing exc.)

Yes Hyflyr, snow is coming soon.

 

[zebiraross]

350 450

What kind of boost are you running and what elevation. I'll assume your 6Kft or so in Canada. The 28rs is a great turbo. Especially at sea level. Once you start jumping in elevation it drops a TON in effeciency. It flows a decent amount of air, but doesn't has a crappy pressure ratio, meaning going up in elevation compressor effeciency drops and the amount of boost you can run drops. at 6K ft your limited to about 19 psi with a rs, anything after that you will be out of the compressor map.

The 2871 is a great turbo, especially when factoring in elevation. It has a great pressure ratio. Especially the 52 trim. It has a 3.1 pressure ratio which means you can run up to 24 psi at 6K ft. The 56 trim flows a few more lb/min, but has a lower PR.

Turbine housing size with the T25 flanged turbo's being fairly small anyway I would go with the .86 a/r.

28rs is a 350 hp turbo great throttle response
2871 is a 450 hp turbo great top end but a little laggy compared to the 28rs.

 

[HYFLYR]

Since we only ride around sea level to 4k i would say 28rs would be fine up to 22lbs on most days. When we ride up in summit or cantwell we are still below 6k feet 95% of the time. In my opinion the rs will be plenty for around here, has good throttle response but can still run big boost without outrunning the compressor efficiency in our nice thick air.

I know alpine had been testing different housings and what not to get good response and nice top end pull, rip&tear might be the guy you want to talk to about all that though. In the end though, we need snow!

 

[RIP N TEAR]

I have tested with the 28rs, 2871 and 3071. My personal favorite is the 2871, great throttle responce and pulls hard up top.