THOUGHTS: FITTING GT2871R to stock engine without mods.. Only revo stage 1...

[Dscott]

Hi,

You're advice is much appreciated. Thank you.

Sorry what i meant by my last comment was; if i literally bolted the gt2871r on + injectors 'only' to a stock setup and then got it tuned to run - i would no doubt have to get another tune once the i/c, maf & exhaust where fitted,obviously to get the most out of the setup.


D

[DNA Tuning]

Ah yes, sorry I was mistaken. Also, I'm more than happy to give you advice or at least point you in the right direction.

You will find that many of such builds take many months to complete; it's all about choosing the components piece by piece, custom tuning, which also takes place step by step; etc. with certain roadblocks along the way. Getting to the destination is part of the fun though trust me!

[gldgti]

Look at the compressor maps.

At pressure ratio of about 1.6, the garrett is going to be out of its efficient range at a nominal "coming on throttle at mid rpm's" type flow number of 0.07kg/s. The K03 is in its efficent place for the same flow and pressure ratio.

I would say that at low-mid rpm, the big turbo will work fine but it will be slower than with the k03. at high rpm, when the garrett unit becomes more efficient, you will see the reverse effect (which is bad for any given tune, because you will "lean out".

Turbo compressor maps are not the enemy. People (all people on car forums who are into turbo's) should really take the time to understand how to read them and use them in order to make decisions about turbocharging. There's great satisfaction in understanding the physics, doing the calucations and having your results verified inthe real world, as I have done personally. Much nicer than learning through doubtful heresay on forums (not that anyone said anything really wrong, its just that its better to know why, than just to know.)

[parso_rex]

On that note Garrett have some great tech docs if your up for a bit of light reading

TurboByGarrett.com - Turbo Tech101
TurboByGarrett.com - Turbo Tech102
TurboByGarrett.com - Turbo Tech103

Doc 1 is pretty basic, 2 and 3 is where the calculator has to come out. Most don't make it past 2

[Dscott]

Hi Guys,

Thanks for your thoughts, i am confident with my choice of turbo, i've done quite a lot of research.

My main concern was: Will it run too lean on my Revo stage 1? I am assuming there is no way to be certain, unless i log it or dyno it?

D

[gldgti]

Mate - the only way to know if it will run lean, is to know what a/f ratio you have now at various rpm/throttle settings, and then try to calculate flow data from the compressor map for your new turbo and compare it to your current thinking - i.e. - its pretty much IMPOSSIBLE to say. The only way anyone could give you the answer you want is if they had the same car/engine/turbo/tune as you, and did the same thing themselves, and tested it.

Anything else is a stab in the dark!

[tommymac]

ah thye ol AFRs bain of my life.....