2JZ best single turbo

[JustenGT8]

Been sniffing too much avgas there Presha? or suffering 18RGT withdrawals

I'm sure 1400hp would make for an interesting tow car though

[beerhead]

+Antilag and it'll spool at the goal RPM

[boxh34d]

We put a 3582R with .63 rear on a mates 2J, really chokes in the top end. The owner ended up switching to a .82 rear and only had a small change in spool with a much stronger top end.

I've got a .82 35R on my vvti 2J also and it's awesome for a daily driver, really responsive.

Don't suppose you have dyno sheets before and after the change of housing?

[JP]

I dont but I could get a printout with an overlay the next time I head back to the dyno.

[JustenGT8]

That would be good, just out of interest sake. My GT35 err knockmoff turned up. Looks fine but not a true GT3582. I think that will be a plus though as even though it has the 0.63 housing is has a bigger trim turbine wheel in there. No way this turbo will choke below 500hp. I'm still more worried about spool, but if a 0.82 spools nice then this turbo will still spool quicker...which is good

[Phoenix01]

This isn't a before and after. But this is my 3582 .82 housing dyno graph.



To give you an idea of the power band, that's roughly 3,900rpm @ 70mph and 5,900 @ 105mph. I'm running stock cams which I figure is what makes the torque curves gradually decline after 4,750rpm (85mph).

The pink lines are at 17psi, the red & green are @ 22psi.

[JustenGT8]

Cheers mate. With a manual i'd be happy with that i think, maybe a touch slow in response for my lazy cruiser....i reckon my bastardised 0.63 with bigger wheel will do nicely based on your results.

[Phoenix01]

I don't know if the loud pedal was fully depressed until 65mph because my previous graph looked like this:



The only changes between this and the pink line on the newer graph were new injectors, fuel pressure reg, cdi and coils (same boost).

But yes, the 0.63 housing should be perfect for a tow car/cruiser. As I mentioned earlier, I doubt you'll see anything more than 300rwkw with that housing at most, though I know that's not the important part.

[Phoenix01]

Oh wait, in retrospect, maybe its just the scale that makes the newer graph look more gutless in the bottom end. Either way, its got reasonable grunt down low, but yeah a .63 should see significant gains in that area.

[JustenGT8]

Ta mate. At worst i can change to a 0.82 in future if i need to. Thanks for the dyno prints, you car gets along nicely i bet

[Phoenix01]

It would, but traction eludes me.
4.11 final drive and 235 tyres don't help.

[boxh34d]

That's quite interesting. Not quite enough meat in the low end for my particular goals, but that certainly gives an idea into the potential of this turbo on a 3 litre. Your engine certainly comes alive with that 5psi extra boost though!
Thanks for that.

[Phoenix01]

Yeah it certainly does. Keep in mind that the motor has been rebuilt with an 8:1 comp ratio. So the low end is going to be slightly worse than an unopened 2J.

[beerhead]

I'm a firm believer in small rear exhaust housing on all turbo setups after seeing a ford sierra make 600hp with a very restrictive rear housing. They ran 2 decent size external wastegates to flow the extra exhaust gasses so that top end doesn't get sacrificed due to trying to squeeze all it's exhaust through a restrictive turbocharger whilst causing boost creep and other endless problems. It gets rid of the "there must be an apple in muffler feeling" of a motor running out of top end puff.

[Joshstix]

Just on the topic of turbine housing sizing. One of the tuners in the US that does a lot of MR2 work did a comparison of the .63 and .82 housings on his daily driver MR2. It is a pretty interesting read if you have an account on MR2oc http://www.mr2oc.com/showthread.php?t=418082

If you don't have an account the crux of the matter is swapping to the bigger housing improved response and area under the curve at the same boost level even on a little 4 cylinder. The below graph is the comparison between the two housings the blue line is the .84 and the red line is the .63 housing



Admittedly it's not really a suitable power curve for use with a slushbox but with 50% more capacity I'd imagine you would be OK.