help me pick a turbo

[kaneda3]

ok ok ok ive searched and came up with the typical disco and big t28 threads

but i want somemore opinions

heres my setup so far(just counting parts needed for power)
redtop
FMIC
3" exhaust all the way
Walbro Fuel Pump
550cc injectors
Z32 MAF
Apexi Power FC
a great tuner, a dyno, and a wideband



what i want is turbo that is pretty much a straight bolt in
that can make 270ish rwhp on a daily basis
has great response and real usable powerband
and can still easily make 320ish rwhp when it needs too(but still well within its range)


let me know what you guys think and if there is a turbo for me


on a side note
i just parted ways with a blitz 450r turbo kit i was making 379 to the wheels which was cool and all but that turbo was a tad unruly... nuthing like 18psi slamming you in the ass all at once, between 3800 and 4300 rpms

mike

[wootwoot]

You must not be any good at searching, gt2871r with .64. Get cams as well.

[kaneda3]

no see i saw people mentioning the 2871
but no real info

many people using it?

and i dont think i want to go as far as installing cams...
want little to no downtime and as little money as possible

[speeddreamz]

even the gt25r , or fp big t8 will do good, gt25r in the .64 or .63 a/r? ferget, the lower one, not the .86 a/r.


and yes people are starting to use the 2871 its yielded good results, check fresh alloy they got a lot of people using it.

[Drunk Bastard]

T78 all the way!

[RBS14]

I've also heard great things about 2871r. .63 housing not .86 I read from a respectable souce that it acts much like a S15 turbo, but spools faster and has potential for some extra power too.

[KoukiMonster]

gt2530


dfafdafasd

[Var]

this is a long thread but read it cause it has good info


http://forums.freshalloy.com/ubbthreads/showflat.php?Cat=&Board=UBB9&Number=67784453&page=&view=&sb=5&o=&fpart=1&vc=1

[kaneda3]

thanx for the thread

but i have yet to find a good dyno chart showing the gt2871r with the .64

all ican find are the .86
here is a comparison of the disco vs. 2871/ .86

http://www.atpturbo.com/root/releases/images/release062104/gt2871r_dyno.gif

[Var]

The disco is nice. If you got some step 2's and a manifold the powerband would be pretty awesome. 4-8k. That's the way i'm gonna go when it's time. Probably in less than 4 months. After reading that thread on FA , i too am interested in what the .64 does. It may be worth it.

I looked on cheapturbos.com and for some reason they have the same specs listed for both .64 and .86 turbos. Here are the links

Disco Potato (http://store.yahoo.com/cheapturbo/gagtdpo.html)


Garrett GT2871R .64 a/r (http://store.yahoo.com/cheapturbo/gagt64ar.html)


Garrett GT2871R .86 a/r (http://store.yahoo.com/cheapturbo/garrettgt2871r.html)


if these arent correct link me to the appropriate specs. thanks

[kaneda3]

any opinions on this setup?


crap i lost the link

anyway its frp big t28
t28 internals in a t25 housing


mike

[Var]

Supposedly this is a quick spooling turbo and it's good for a little over 20psi. But you have to push 20psi to get 300hp. People that buy em are usually happy. The great part is that it's a t25 housing so it's a DIRECT bolt on affair.

[wootwoot]

A god of tuning once told me that at 18psi with a gt2871r with the .64(maybe .63 who knows im retarted) you should be able to make 360whp with an intake manifold. Get cams man, you they are more bolt on than a turbo is

[sykikchimp]

The HKS GT2530, or the Disco potato will produce better response than a gt2871r even in the .64 ar turbine. And they will both support the goals your looking for.

[Jeff240sx]

Can you guys not follow the torque curves? Sure, the 2871 spools a bit slower, but at the top end, it will give more pull. The DP will simply crap out and blow hot air. You can clearly see it's giving up on the dyno sheets. However, this is assuming that those two dynos are the same car with same mods at the same boost levels. The 2871r is a better turbo solely by the graph. More area under the curve = faster car. Torque lasting longer = power up top. The disco potato at 8000rpm would be a joke.
-Jeff

[Var]

Can you guys not follow the torque curves? Sure, the 2871 spools a bit slower, but at the top end, it will give more pull. The DP will simply crap out and blow hot air. You can clearly see it's giving up on the dyno sheets. However, this is assuming that those two dynos are the same car with same mods at the same boost levels. The 2871r is a better turbo solely by the graph. More area under the curve = faster car. Torque lasting longer = power up top. The disco potato at 8000rpm would be a joke.
-Jeff


Both torque curves drop significantly so i doubt either turbo is running out of breath. I think with better cams the DP would at the least even out the HP line towards red line. It doesnt have to keep rising for me. I'd rather have all the torque up there at 4k and then have it slightly taper and have the horsepower pick up a little bit and then stay even to redline. This is for drifting mostly, i dunno if it makes a difference but when you are sliding the engine is under a lot of load with sticky tires. You need that torque down low to get the tires spinning, then when the engine reaches it's high end, the hp and centrifugal force of the engine spinning @ 6-8k will be enough to keep the revs high. Most of the time you are staying in the same gear anyways. So as far as the dyno shows, you are right jeff. ..the 2871 is definitely better for power and torque but it looks like it will need a clutch kick here and there

[Jeff240sx]

Both torque curves drop significantly so i doubt either turbo is running out of breath. I think with better cams the DP would at the least even out the HP line towards red line. It doesnt have to keep rising for me. I'd rather have all the torque up there at 4k and then have it slightly taper and have the horsepower pick up a little bit and then stay even to redline. This is for drifting mostly, i dunno if it makes a difference but when you are sliding the engine is under a lot of load with sticky tires. You need that torque down low to get the tires spinning, then when the engine reaches it's high end, the hp and centrifugal force of the engine spinning @ 6-8k will be enough to keep the revs high. Most of the time you are staying in the same gear anyways. So as far as the dyno shows, you are right jeff. ..the 2871 is definitely better for power and torque but it looks like it will need a clutch kick here and there

I don't drift... so I don't really know whats necessary, however, I'm almost positive of one thing. Most drifters don't drop below 5k intentionally. From 4K and beyond, the gt2871 beats the DP. And "I think with better cams the DP would at the least even out the HP line towards red line" surely. But add that setup to the gt2871 and you still have the better turbo setup.
The DP goes from 329 ft/lbs to ~172 ft/lbs @ 7k. That's 52% (or so) of it's peak. The gt2871, however, goes from 322 ft/lbs to about 220 ft/lbs @ 7k, retaining nearly 70% of it's power. It's making about as much torque at 7k as the DP is making horsepower. The gt2871 makes the same ammount of torque as the DP at any point, but does it 700-800rpms later (6600 vs. 7200). This isn't a hard decision here.
We are talking about a torque peak moving from 4500 to 4800 or so.
The torque will never "always increase". It will decrease at an anticipated level, giving the feeling or normalcy. However, if you rode in both of those cars, the DP would feel lethargic up top. Because it is.
-Jeff

[Var]

O..you are absolutely right. i was mistaken at looking at the lines. I guess i really cant follow the torque curves. :cry: Looking at the graph again you is right masta. :bowdown:


If the the dyno graph DOES show the same exact motor with the only difference being the turbos, i'd go with the 2871 .86. Where did this dyno graph come from anyways? is it a reliable source? The .64 should show a little quicker spool than the .86 with a little better top end than the DP right?

p.s. and boost levels?

[sykikchimp]

I think it depends on what you want from the car.

If you look at the HP curves, you can see the DP is quite a bit more linear than the gt turbo. Looks like it will follow allow you to be able to control the power better in low speed, low rpm situations were finese is critical. In a low speed corner (grip) having the additional power down low in the rev range allows you to not have to downshift for that corner. Downshifts slow you down.

From where I sit, the dp may run out of steam up top, but looks more controlable where control is needed.

I'm betting that on a KA the additional displacement, and the .64ar housing on a GT2871R will have a similarly controlable powerband low in the revs, and not run completely out of steam in a ~300hp car.

"power is nothing without control"

--but we are talking about small nuances.--

[Jeff240sx]

Autox/road course, you'd want the DP, no question there. However, max power/drift @ 5krpm and above.. I'll take the 2871.
edit: nm, I got it.
-Jeff

[Var]

I'm betting that on a KA the additional displacement, and the .64ar housing on a GT2871R will have a similarly controlable powerband low in the revs, and not run completely out of steam in a ~300hp car.


Dont forget about manifold design. If you run a tubular mani on an SR you can get .64 spool times with a .86 housing AND more power. Ideal setup as of what i learned right now.

Sr with mild port job
Piston/Rods
Silkroad Turbo Manifold
Greddy Intake Manifold
2871 .64 A/R
256/264 cams

[Var]

Autox/road course, you'd want the DP, no question there. However, max power/drift @ 5krpm and above.. -Jeff


There are some courses where your revs drop as low as 2500 rpm in second gear(not racetrack but cone courses where the affordable drift events are) . My t-25 keeps the tires spinning even at this rpm but not great tires. 5K plus would be ideal but not possible

[kaneda3]

something has to be pointed out

thse dyno charts are from a VW but everything is the same between the 2 graphs only the turbos were changed

[Jeff240sx]

The car doesn't matter.. it's the trend we're looking for. Knowing that nothing else was changed is good though.
-Jeff