Turbo upgrade discussion
05-14-2009, 09:00 AM
#13
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The bearing differences have a lot to do with spool. A BB turbo has much less friction than a sleeve oil film bearing turbo allowing it to spool faster. The newer design of the turbine blades also contributes to its quicker spool.
It's been argued that the BB may not be as reliable as the older type bearings and that the older bearings are easily and cheaply replaced if there ever was a problem.
It's been argued that the BB may not be as reliable as the older type bearings and that the older bearings are easily and cheaply replaced if there ever was a problem.
05-14-2009, 09:19 AM
#15
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I'm in exactly the same boat as you and I'm leaning toward the 2871. The only other choice for me would be the RS2. The RS2 is a very reliable and well proven combination, but for a little more $ the 2871 offers 45 more hp. The RS2 actually makes 15 more lb.ft of torque than the 2871 and more hp below 4300, but above 4300 RPM the 2871 has a significant torque and hp advantage.
I guess it comes down to where you want your power. The RS2 has the best punch below 4300 and the 2871 has the clear advantage above 4300. From looking at the graph IMO the 2871 would be faster in a race where you're pulling to redline in each gear. The RS2 would be slower in an all out race, but might offer more useable power in the daily driving range.
Lag is another issue that isn't shown on the graph Nate posted. The 2871 is probably much faster to react to large throttle changes due to it's much newer turbine design and ball bearings. I haven't seen any hard data to support this. I've just heard a couple people's opinion after driving both.
Another cost you'll need to consider is upgrading the fuel pump. I would not even think of running anything bigger than a K24 on the stock pump. That adds about $300 to any upgrade option.
I guess it comes down to where you want your power. The RS2 has the best punch below 4300 and the 2871 has the clear advantage above 4300. From looking at the graph IMO the 2871 would be faster in a race where you're pulling to redline in each gear. The RS2 would be slower in an all out race, but might offer more useable power in the daily driving range.
Lag is another issue that isn't shown on the graph Nate posted. The 2871 is probably much faster to react to large throttle changes due to it's much newer turbine design and ball bearings. I haven't seen any hard data to support this. I've just heard a couple people's opinion after driving both.
Another cost you'll need to consider is upgrading the fuel pump. I would not even think of running anything bigger than a K24 on the stock pump. That adds about $300 to any upgrade option.
05-14-2009, 10:03 AM
#16
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I found BNIB RS2 Comp Turbos for $1300 locally, so that puts an RS2 kit at around $2300.
updated original post
updated original post
Last edited by Chapel; 05-14-2009 at 12:28 PM.
05-14-2009, 10:12 AM
#17
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For any of these setups a FMIC is strongly recommended. I have 3071 pulls from the same dyno, the power is within a couple HP, same car, we did our best to calibrate our dyno to the old mustang we were using.
Here's a pile of spaghetti with most of our current offerings overlaid:
Here's a pile of spaghetti with most of our current offerings overlaid:
The 3071R doesn't make that much more power and makes torque a lot later with the simple chip tune... I'm sure it's got a lot more potential if I were to do a full custom tune, but I think the 2871R with chip tune is the better bolt-on daily driver.
Last edited by Chapel; 05-14-2009 at 10:15 AM.
05-14-2009, 11:05 AM
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I was on the same boat.Finally,I went for GT2871R from 034.it doesn't mean the RS2 turbo is bad.In the long run,You'll gain on the RS2 setup in terms of serviceable.after my consideration, I added a few bucks and getting the newer technology.I never had the car with BB turbo.that's why I go for it.
Trent was told me before it's a pain for routing the coolant line under the IM for the 2871 setup.So make your choices!.
Trent was told me before it's a pain for routing the coolant line under the IM for the 2871 setup.So make your choices!.