Rb28dett Turbo Choice.....

[9krpm]

Well I am happy to test if someone has a set of turbo lying around

Engine may come out at the end of the year for a refreshment.

I will probably remove the ABS too so it should help with the change over process.

In reality I doubt that T618z/GTRS would make much difference for what you are doing xrated, unless you plan to take the car on a tight circuit as well.

With NOS and drag racing, I would probably go for the TD06 6cm and then upgrade it to the larger exh housings for more top end power if required.

I've driven 3 x RB26/30 GTRs with TD06 8cm ( or was it 10cm), HKS T51R, T618z and T517z.

Engine specs and tuner were the same. The response is the reverse of the above order and max power is in that order.

The TD06 came on very strong and was very exhilarating to drive.

[discopotato03]

Sorry I don't know much about Greddy turbos - they are Mitsubishi based aren't they ?

I prefer Garrett because I think their wheels are better designed for high performance petrol apps in the small/medium size ranges . They could offer a few more trim options at times though .

In a way we are lucky that HKS played with some of them to better suit engine specific apps . They cost but they also generally deliver a known result and that can sometimes be better/cheaper than doing all the spanner and development work yourself . If they use Garretts own housings often they can be ordered through Garrett at a Garrett price as well , thats how I managed to get my GT3037/Gt3076R 52 trim port shrouded turbo . It doesn't have a HKS turbine housing but Garrett make quite adequate ones for my application anyway . You jusat have to be lucky and know the part numbers .

I'm pretty sure you can buy a version of the GT2871R 52T (same cartridge as GTRS) with housings to suit an RB26 .

The ducks guts would be that TR30R competition turbo (wheels actually) Garrett won't give us for sane money , two of those on an RB26 with suitable housings really would stop the rotation of the earth . Same turbine family as those in GT2530/GT2860RS/GTRS (9 bladed 54.4mm 76T) but in 60mm and 76 or 73 trim . Standard options have 5/10 bladed comp wheels but you could possibly pinch something from the 5/10 bladed Mitsubishi range to get close . I think Precision in the States sells those compressors . Most of the World Rally Car series ran a version of this TR30R and the Le Mans Audi R8 did well with a pair of them too .

Interesting times .

[XRATED]

Hey Dan, your set up would be the perfect test bed.... It's stout enough to push any of these turbo's to the limit.

I just had a very interesting conversation with a custom turbo manufactuer in the US. He said he could copy almost any comp wheel design and machine it from billet. Also, depending on the turbo, he can re-core with ball bearings. He's just a guy in a workshop who re-builds large diesel turbos mostly... ha ha ha what a find!

Veeeeery interesting.. Billet, BB Trust turbo???

[Lithium]

Sorry I don't know much about Greddy turbos - they are Mitsubishi based aren't they ?

I prefer Garrett because I think their wheels are better designed for high performance petrol apps in the small/medium size ranges . They could offer a few more trim options at times though .

I know you know the Garrett catalogs better than anyone, but that above was an awesome contradiction - you don't know for sure which manufacturer Greddy turbos are based on but the wheels are still better designed? I really respect your turbo knowledge but seriously...

I don't know the answer of the T618Z vs GT-RS comparison, but don't underestimate the offerings from Mitsi. I also would have thought that a T518Zs would have been a closer equivalent to a GT-RS? I know in the real world I would sooner go with a Mitsi TD05-16G than a Garrett GT2871R - in single form. They are honestly the closest thing to "Too good to be true" I have come across in a small frame turbo suitable for up to 400hp.

Edited October 12, 2009 by Lithium

[aDrew_C]

GT4088R gets my vote for sure or twin GT-RS's if you have to go twins. 4088R will get you the power without sacrificing response too much.

[The Dan]

Why would anyone pick a 4088 for 450rwkw when the 3788 has the same compressor but smaller turbine than a T04Z.

And it will still make 450-480rwkw.

[Lithium]

Hmm I think a pair of GT-RS would outflow a GT4088R, and on the same note also be laggier. We'll see how RIPS' GT4094R RB30 goes with the GT4094R as there are RB30DETTs running GT-RS to compare it with, in theory they should be the most comparable combinations mentioned so far.

Do you know anyone who has used a GT3788R? I'd be interested to hear how they react on a petrol mootr , I have never heard of one being used on one. I kept a bit of an eye on for them but not sure what to expect. GT4088Rs are a much more known quantity... and I'd happily use one if I were aiming for the mentioned power range!

[The Dan]

Hmm I think a pair of GT-RS would outflow a GT4088R, and on the same note also be laggier. We'll see how RIPS' GT4094R RB30 goes with the GT4094R as there are RB30DETTs running GT-RS to compare it with, in theory they should be the most comparable combinations mentioned so far.

Do you know anyone who has used a GT3788R? I'd be interested to hear how they react on a petrol mootr , I have never heard of one being used on one. I kept a bit of an eye on for them but not sure what to expect. GT4088Rs are a much more known quantity... and I'd happily use one if I were aiming for the mentioned power range!

From what I have heard from the guys running them on XR6's, one guy had a T04Z on his XR6T running 18psi and made the same hp on the same boost when he changed it out for a 3788 but a lot earlier.

Unfortunately I don't have any maps for a 4088 1.06 or I could tell you exactly when it'll come on

[Lithium]

How are you going to tell when a turbo would come on from maps, and without info on the rest of the setup?

[The Dan]

How are you going to tell when a turbo would come on from maps, and without info on the rest of the setup?

I would base it on calculated airflow for a standard rb26.

Remembering that we need to compare them equally, it is the only way. Porting and cams etc can make differences which I can factor into the equation but generally if you can tell me AFR's and how much hp, then I can calculate the gas/air flow from the engine.

I made a calculator in excel ages ago, I'll have to dig it up again.

[Lithium]

Yeah I can understand estimated power, but the spool is a bit different. Oh yeah, wouldn't be surprised if a GT3788R matched a T04Z in power and exceeded its spool (a GT4088R probably would outspool a T04Z too) but I wouldn't be too surprised if a T04Z made more power when pushed hard so not really apples with apples.

[BoostdR]

Garrett 2871R-10 x 2 we have made 824hp @ 22psi on BP98 (RB30/26) very responsive

or if you could get a couple of RB25 Turbos to be reliable....that would be my next pick. I have one on my 1.6 mazda. Makes full boost at 2900rpm. 1psi @ 1600rpm, 2.5psi @ 1900rpm, 7psi @ 2400rpm. Not bad for a 1.6ltr. redlines @ 7500rpm thats 4600rpm of full boost. Ceramic turbine FTW

[BoostdR]

Sorry I don't know much about Greddy turbos - they are Mitsubishi based aren't they ?

I prefer Garrett because I think their wheels are better designed for high performance petrol apps in the small/medium size ranges . They could offer a few more trim options at times though .

In a way we are lucky that HKS played with some of them to better suit engine specific apps . They cost but they also generally deliver a known result and that can sometimes be better/cheaper than doing all the spanner and development work yourself . If they use Garretts own housings often they can be ordered through Garrett at a Garrett price as well , thats how I managed to get my GT3037/Gt3076R 52 trim port shrouded turbo . It doesn't have a HKS turbine housing but Garrett make quite adequate ones for my application anyway . You jusat have to be lucky and know the part numbers .

I'm pretty sure you can buy a version of the GT2871R 52T (same cartridge as GTRS) with housings to suit an RB26 .

The ducks guts would be that TR30R competition turbo (wheels actually) Garrett won't give us for sane money , two of those on an RB26 with suitable housings really would stop the rotation of the earth . Same turbine family as those in GT2530/GT2860RS/GTRS (9 bladed 54.4mm 76T) but in 60mm and 76 or 73 trim . Standard options have 5/10 bladed comp wheels but you could possibly pinch something from the 5/10 bladed Mitsubishi range to get close . I think Precision in the States sells those compressors . Most of the World Rally Car series ran a version of this TR30R and the Le Mans Audi R8 did well with a pair of them too .

Interesting times .

TR30R on EVO 9. Nice Torque

[bigmikespec]

Sorry I don't know much about Greddy turbos - they are Mitsubishi based aren't they ?

I prefer Garrett because I think their wheels are better designed for high performance petrol apps in the small/medium size ranges . They could offer a few more trim options at times though .

In a way we are lucky that HKS played with some of them to better suit engine specific apps . They cost but they also generally deliver a known result and that can sometimes be better/cheaper than doing all the spanner and development work yourself . If they use Garretts own housings often they can be ordered through Garrett at a Garrett price as well , thats how I managed to get my GT3037/Gt3076R 52 trim port shrouded turbo . It doesn't have a HKS turbine housing but Garrett make quite adequate ones for my application anyway . You jusat have to be lucky and know the part numbers .

I'm pretty sure you can buy a version of the GT2871R 52T (same cartridge as GTRS) with housings to suit an RB26 .

The ducks guts would be that TR30R competition turbo (wheels actually) Garrett won't give us for sane money , two of those on an RB26 with suitable housings really would stop the rotation of the earth . Same turbine family as those in GT2530/GT2860RS/GTRS (9 bladed 54.4mm 76T) but in 60mm and 76 or 73 trim . Standard options have 5/10 bladed comp wheels but you could possibly pinch something from the 5/10 bladed Mitsubishi range to get close . I think Precision in the States sells those compressors . Most of the World Rally Car series ran a version of this TR30R and the Le Mans Audi R8 did well with a pair of them too .

Interesting times .

Owen Developments sell the motorsport variety of Garrett turbochargers, built to handle WRC antilag (comes at a cost) but they are a V-band external wastegate, would make an interesting setup on an inline 6 in a twin config... or even in a single, maybe (go for the largest TR30 variant)...???

Depending on how extreme you go (as there are apparantly over 100 variants of the TR30) they range from like 6000-12000 pounds...

Edited October 13, 2009 by bigmikespec

[discopotato03]

I have four compressor maps from a couple of different diameter TR30R compressors ie a 40 and 56T 69.3mm one and a 40 and 56T 76.2mm one . They call the two 40T wheels BCCW5 and the 56T ones BCCW28 .

Garrett mentions these four span a power range of 200-560 Hp which I take to mean the smallest 200 and the largest 560 .

The maps for both 56T wheels look the goods and they show them pumping ~ 44 and 56 pounds respectively .

It's maddening to think that the dimensions of some of these wheels is not drastically different to a real off the shelf GT3071R and what a turbo it could have been with the 60 mm NS111 turbine , available in 73 and 76T , and the 56T 69.3mm BCCW28 compressor wheel .

They say every TR30R is an individual order and some of the major components can be had in Stainless or Titanium so strong and light . I imagine there are heaps of housing options so having 100 variations wouldn't be too difficult .

I wonder if the _____se will ever copy them .....

[bigmikespec]

Just found out that the TR30 billet compressor wheels will not fit HKS 2530's (and Garrett equivalents) due to differences in the shaft diameter

PS: disco, I hope the _____se do not, some things need to remain "sacred"

Edited October 13, 2009 by bigmikespec

[discopotato03]

Its not the compressor wheels that interest me so much , mainly that 60mm NS111 turbine . It is the center piece of that TR30R turbo family . I think I may have read once that its material is Mar M and not Inconnel like most of the production performance petrol app turbines .

I'm not really for the "ese" copying it but if Garrett thought they were they might make it available themselves . Mongrels - its really not that hard to do , if they can get the larger trim and higher flowing GT30 UHP wheel on a GT28 shaft the TR30 one would not be any more difficult .

Billet compressor wheels are overkill IMO unless you really are going to turn mega shaft revs and very high boost pressures like in a real competition application . A cast and machined compressor is far cheaper to produce in volume which is why most are made that way . There is the advantage of being able to make a customised or very low volume series of wheels from a billet on a five axis CNC mill because that's cheaper than making moulds and tooling up to cast them in low numbers .

As far as the compressors bore hole is concerned they can machine virtually any size hole and even thread that will fit in the hub of the wheel without weakening it . Garrett's GT37 and GT40 compressors in the GT3076R and GT3582R (GT3840R) are designed to go in large frame diesel turbochargers and are usually larger thread bore wheels std . When Garrett chose to fit them in the two turbos I just mentioned they simply bore a smaller plain hole in the casting and face most of the hexagon off its nose . Actually the back spacing is altered as well but you get the picture .

A .

Edited October 14, 2009 by discopotato03