Outer Limits 4x4 Board

How do you get the turbo to line up as in getting inlet and exaust in the right place. Looking at a gt2876rs on an AE86 corolla , where the outlet would be facing down when bolted to a 1HZ or so it looks. Can the inlet housing be spun to suit the job needed or do they have different configurations? Not sure if i missed it Z()ltan but did you get that intercooler of your's working? Would like to see some pics if possible.

SimonInAustralia wrote:
The definitions seem to suggest that smaller AR is better for low revs.

It seems to make sense, less air required to get the turbo spinning, which is what you have at lower revs, but then a greater restriction at higher revs, for less maximum power.

Remember there are two ar numbers to take into account.

The exhaust ar on my turbo is very small (.64) So fast spool
The compressor ar is .70 with a huge inlet, per rotation of the smaller turbine wheel the inlet wheel displaces alot of air. So fast boost.

rowenb wrote:How do you get the turbo to line up as in getting inlet and exaust in the right place. Looking at a gt2876rs on an AE86 corolla , where the outlet would be facing down when bolted to a 1HZ or so it looks. Can the inlet housing be spun to suit the job needed or do they have different configurations? Not sure if i missed it Z()ltan but did you get that intercooler of your's working? Would like to see some pics if possible.

The compressor housing is clamped to the center cartridge so you can loosen the bolts and rotate the housings independently.

Yeah ive got the cooler working mate, its shaved off 150 deg on egts so far. I have some extra mods to do also now that im running 25psi

The GT2860RS has two options .64 and .86, the .64 will spool up lower in the rev range giving better low down response over the .86 which will give better top end performance.

Zoltan's GT28776R with the .64 housing will spool up quickly but not as quick as the GT2860RS as it has to drive a larger compressor housing but again will give better top end performance.

Simple analogy is 33" tyres as opposed to 35" on the same vehicle, we all know that effect on performance.

For a daily driver the GT2860RS will give better boost lower down over the GT2876R.

One point I will make is the DTS turbo is not as bad as you may think, on Marin,s TD42 Mav the DTS was prior to intercooling mediocre. With it well intercooled it gained 26% more power and 29% more torque just on the DTS turbo and was completely different to drive.

Infact as a daily driver I preferred the DTS to Marin's current GT2860RS, yes the GT2860RS gives more boost and power. But it comes down to what you want to use it for.

matt.mcinnes wrote:Zoltan's GT28776R with the .64 housing will spool up quickly but not as quick as the GT2860RS as it has to drive a larger compressor housing but again will give better top end performance.

...

For a daily driver the GT2860RS will give better boost lower down over the GT2876R.

Thanks Matt.

In terms of top end performance, in a low revving diesel like a 1HZ, in what sort of rev range is the larger GT2876R going to give improved performance over the smaller GT2860RS?

In a daily driver, where you are probably working in the 1500-3500 rpm range most of the time, is the top end performance that the larger turbo gives going to be of much use?


It is interesting what you say about the DTS turbo, might have to give intercooling a go before going a bigger/different turbo.

Was Marin's intercooler a DTS kit, or custom, to give those improvements?

SimonInAustralia wrote:

matt.mcinnes wrote:Zoltan's GT28776R with the .64 housing will spool up quickly but not as quick as the GT2860RS as it has to drive a larger compressor housing but again will give better top end performance.

...

For a daily driver the GT2860RS will give better boost lower down over the GT2876R.

Thanks Matt.

In terms of top end performance, in a low revving diesel like a 1HZ, in what sort of rev range is the larger GT2876R going to give improved performance over the smaller GT2860RS?

In a daily driver, where you are probably working in the 1500-3500 rpm range most of the time, is the top end performance that the larger turbo gives going to be of much use?


It is interesting what you say about the DTS turbo, might have to give intercooling a go before going a bigger/different turbo.

Was Marin's intercooler a DTS kit, or custom, to give those improvements?

Marin's was one of my intercoolers, but regardless of that I would intercool 1st to see if you have what you want, before upgrading the turbo. You will need to intercool either way to get the best of the GT28 turbo. So intercool and tune first and she if your happy with the DTS, if you want more then go the GT28.

ok here is some of matts intercoolers that he has done. they are not cheap but you get what you pay for. the last thread is the one that i am doing for my 1hdt


http://www.outerlimits4x4.com/ftopic139 ... t=laminova

http://www.outerlimits4x4.com/ftopic164 ... t=laminova

http://www.outerlimits4x4.com/ftopic201 ... t=laminova

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWAX:IT

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWAX:IT

looking at these, are they cheap cr*p, unsure with the sizing eg A\R
A GT2876r is the 76r the exhaust A\R, can someone explane the letters and numbers please,
Paul

gt28 refers to the turbo series.
the 76 refers to a 76mm compressor wheel.
for a diesel you will want a .64 a/r on your turbine side.
a .86 a/r on a diesel will be to laggy.

a gt2860 has a 60mm compressor wheel
a gt2871 has a 71mm compressor wheel
a gt2876 has a 76mm compressor wheel

you can get these in either a .64 or .86 a/r (turbine side)
then you can get a different a/r for the compressor side. (from memory this a/r is fixed)

when i was looking for a turbo to replace my ct26 on my 1hdt i was told by mt turbo shops that the gt2860 is the way to go. they all told me that the gt2871 and the gt2876 where to big and would require internal pump mods as the standard pump would not supply enough fuel.

also if you can get some one to explain to you about turbo maps and you can size it that way. or just go with your gut and by one and see what the outcome is. this is what i was told by a few.

Paul Smith wrote:http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWAX:IT

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWAX:IT

looking at these, are they cheap cr*p, unsure with the sizing eg A\R
A GT2876r is the 76r the exhaust A\R, can someone explane the letters and numbers please,
Paul

http://www.turbobygarrett.com/turbobyga ... rgers.html

A few are running GT2871 and GT2876 turbos on 1HZ's, doesn't seem to be any great issues? Also, what about the compound turbo build by Big12HT, wouldn't that have a heap more boost that a single GT2871 or 76?

and alot more $$$$$$$$$$$$$$$$$$