Rb26 turbo choice.

[Nesquick]

hey gang,

so my build has been coming along great, but now i just need to decide what single turbo to go with.

car is going to be a DD in summer which sees about 2-3 track days a year with some pretty spirited driving in between. I'm looking for ~450-500 at the wheels running on 91 pump gas (no meth injection or anything like that, just pure pump)

so far, i have built the engine to hold more (i believe. pick out any weak points)

CP Pistons (bored 20 over)
eagle rods
ACL race main + rod Bearings
Cometic HG
BRian Crower Valves. (Std size)
Tomei Adjustable cam Gears
Walbro 255 fuel pump
N1 Oil Pump.

im still buying:

700cc injectors
AEM EMS
Tomei Type B Poncams (<--- not 100% sure yet. if anyone has any objections to that choice, lmk!)


what snail would be a good choice? lookin for a quick spool of course (3500-3750 should be full boost)

anyone got any ideas out there?

thanks
oh and P.S.

if you think i should add anything to the build. just put it out there

[Cjmartz2k]

HX40, gt35r, BW256 are a couple I can think of off the top of my head.

[Nesquick]

i was thinking of the gt35r as well....heard nothing but good stuff about them.

now i need to know what exhaust housing size to get. im leaning towards the .82ar.

is anyone running this turbo with that size? i would like to know what numbers your putting down and at what RPM the boost starts to kick in. remember, im only looking for 450-500 wheel. with a quick response.

[raremotive]

go with a pair of gt2860-9's you won't regret it.

[GTS4-R]

if your shooting that low for hp go with a gt3582r

[Nesquick]

at what RPM range will boost start boosting between the .78 and .82 AR exhaust housings?

anyone have either installed?

[Coolwhip]

One of the shop cars: RB25DET GT3582R twin-scroll T3 .78 A/R = 400whp/300tq @16 psi - 93oct, stock long block... 4k boost was all in for the kill. Ran out of fuel with 680's, mild ignition, no adders.

[WhatsADSM]

If you are really looking for ~500whp and super quick spool like you said (BTW I think that would be an AWESOME powerband BTW). I'd go with a pt 5857. For something that sized it will likely outflow and out spool everything... it is just icing on the cake that they are pretty inexpensive.

If you are looking for something with still decent spool but more headroom (think 550-600whp max) then the 35r, and potentially the expensive TS 35r would fit the bill pretty well and still spool okay.

[Nesquick]

im gunna be sticking with the 35r.

but im again not sure on what turbine to get...... the .63 would be fricken awesome because of the no lag. but not sure if ill hit the 500whp mark.

if i got with the .78, i know ill hit the mark, but then i have the lag. ( i really hate lag btw...).

also, the goals might change again down the line to something lil bit higher. and i would like to have the headroom of the added horsepower. something is telling me to go with the .78.

does anyone have one installed that could help me out?

[julio]

One of the shop cars: RB25DET GT3582R twin-scroll T3 .78 A/R = 400whp/300tq @16 psi - 93oct, stock long block... 4k boost was all in for the kill. Ran out of fuel with 680's, mild ignition, no adders.

Really? What was the duty cycle? That seems like a low # to max out 680's.

OP, def go .78 or .82. I suggest .82 for headroom since I doubt you will notice a boost threshold difference compared to a .78 housing (lag probably wouldn't be noticeable either unless it was a TS setup).

[Nesquick]

any idea when boost will start kicking in with the .82?

[julio]

any idea when boost will start kicking in with the .82?

Trying to predict boost threshold on any setup is pretty tough due to all the factors that play into the equation. But comparing a .78 A/R housing to a .82 housing is pretty minimal considering its only .04 worth of A/R difference. Now that I think of it, the .78 does come with a v-band downpipe flange, that may be worth it in itself.

Do the poncams allow you to keep VTC? That will make a big difference in your boost threshold.

[ItzGenX]

I am going to lean towards a pair of GT2860R -5's for mine unless I can find a nice deal on a good manifold, BB turbo, and wastegate. I can build my own downpipe for either application, but right now it seems a pair of baby snails come out cheaper and can still do the 550whp I am looking for on my setup. I also won't have to worry about buying fancy wastegates and the open dump (got tired of hearing it).