GT28RS .86ar versus GT2871R .64ar

[TURBOKONGEN]

Back to a turbo question here .A lot of good info here .Asking Def here :What would the spoolup be with a GT2871R .64ar versus a GT28RS .86ar .I put a GT28RS on my 1.8l CA18DET engine a while ago(before the GT2871R was available) . It is pretty laggy , but does give a bit more power than the GT28R I had on before . I am running it at 1.5bar(22psi) boost now .I have been thinking about changing to a GT2871R .64ar , but it is not really very much use if they have aprox. the same spoolup .I will probably have to limit boost to 1.2 bar with the GT2871R , as not to destroy my standard engine bottom end .My friend with the fully built CA18DET made 390whp with a GT2871R .86ar a 1.6bar(23.5psi) .The spoolup on that engine is a little slower than mine . Probably 300 rpm slower .

[CA19DET]

well i think you jsut answered your own question. it will spool a little slower but offer more top end power.. it may spool slower, but at less effort on the turbine, maybe lower temps, more power at lower rpm/boost.. there are trade offs.

i think the GT2871R's are the best ~400hp BB GT turbos out there now for 1.8-22 engines, been reding great things about them..

[veilside180sx]

I drove an SR with one a week ago with the .86 housing and it was pretty laggy. I think most would be happier with the .64 housing. i vehicle i drove was putting down around 300 rwhp, so he needs to up the boost to put it a little more into it's effiiciency range, but just my .02.

[c-rad]

The turbine side of the 2871R and 28RS are the exact same so spool up will be about the same. Only difference is a larger, more efficient compressor wheel. The .86 housing IMO would be ridiculously laggy.

[float_6969]

For any turbo that anybody is looking at that plans on driving the car on the street at all, stay away from the .86 backsides. This motor is too small for it. I personally wouldn't use anything larger than a .64 on the CA unless it was a drag only car, and all I cared about was the top end.

[dattodude]

I'm running a .7/.86 Garrett GT28 turbo on my CA18DET. I'm quite happy with it so far. (currently ECU limited to 3PSI/4500rpm), and I've not tuned the car properly yet.

I have the advantage of the CA being in my 800kg Datsun :-)

I'm getting it tuned next week. I'll let you know how I get on. I'll run up to 10psi boost only while I'm running in. Then it's time to get it up in the low 20s as designed.

The car is a (once a month driver). So I don't mind waiting for boost. :-)

But I expect to be at full boost somewhere between 3400-3800.

I'll give more details as they come to hand.

Chris