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View Full Version : GT28R vs GT28RS (yes another turbo versus thread)

sidewaysil80
11-23-2017, 07:47 PM
I am aware of the differences between these two turbos. Had an s15 turbo on a daily/drift car and it was the most responsive setup I’ve ever driven. Went to 2871r, hated how laggy it was and switched back to s15 turbo. Took 6 year hiatus from cars and am now rebuilding a Redtop to oem spec for new car. Black Friday pricing has the s15 turbo for about $700 shipped and the Disco Potato for $900-$1000.

I will potentially be installing PonCams to help increase the mid/top end since these turbos tend to fall off early. Rest of setup includes z32 mafs, power fc, and 550cc injectors. Oem intake manifold fwiw.

QUESTIONS:

Am I correct in assuming the 28RS will be just as responsive as the S15 turbo?

Are the gains up top with the 28RS enough to justify the extra $300?

Has anyone who road raced/HPDE had issues with either turbo running out of top? This car will be used as a street/HPDE platform, specifically at Summit Point, Dominion, and maybe VIR.
gaz_moose
11-28-2017, 11:11 AM
I was under the impression that (on an SR) the 28r would reach about 300/320hp and the 28rs will do 340/360hp assuming they both have the same .64 rear housing.

what size rear did you have on your 2871r
sidewaysil80
11-28-2017, 05:33 PM
I was under the impression that (on an SR) the 28r would reach about 300/320hp and the 28rs will do 340/360hp assuming they both have the same .64 rear housing.

what size rear did you have on your 2871r

My old setup with 2871r was a .64 housing. I'm leaning more and more towards the 28r as I'm only looking for around 300whp and really want to response a priority. I did order the Tomei Poncams over the weekend so hopefully that will give a little mid/top and not really affect the bottom too much give the S15's responsiveness.
gaz_moose
11-30-2017, 01:39 PM
I don't know what the pricing is like over on your side of the pond but a BorgWarner 6258 should see those numbers and be pretty quick getting there.
PoorMans180SX
11-30-2017, 05:08 PM
Has anyone who road raced/HPDE had issues with either turbo running out of top? This car will be used as a street/HPDE platform, specifically at Summit Point, Dominion, and maybe VIR.

Road racing with a bottom mount turbo is a recipe for blown exhaust manifold to turbo gaskets and a ton of heat in the engine bay.

2871r's are definitely laggy, old tech turbos. $1000 for a GT28RS seems pretty steep given it's 80's tech. I'd look for a used GTX or EFR.