20G Discussion: TD05H vs. TD06

[jusmx141]

I was wondering if anyone has had back-to-back experiences with a TD05H and TD06 20G turbo, and what their driveability differences are. I'm basically trying to figure out which one would be best for the '93 TSi AWD I'm building. By 'TD05H,' I mean the turbine only, not the Bastard 20G using the TD05H compressor housing.

The reason I ask is because I have two 20G turbochargers in my possession:
1) Forced Performance TD06 20G- Has the standard Mitsu exhaust housing and a 34mm internal wastegate

2) TD05H 20G- Has a brand new CHRA (including both the turbine and compressor wheels), and has a Bullseye Monster Exhaust housing with a 38mm internal wastegate.

I'm planning on keeping the car fairly user-friendly, running anywhere from 18-22psi.

One of the cars I tune at my shop on a regular basis is a 1995 TSi AWD with a TD05H 20G, and I really like the spool time and the top end pull, but would the bigger turbine on the TD06 cause a noticeable increase in lag? I was also wondering what the differences in max power output would be between the two.

I'd also like to hear from anyone who replaced their standard Mitsu exhaust housing on any TD05H turbo with a Bullseye unit....how did it effect your spool time and power ouput?

Sorry for all the questions, I'm definetly not a DSM newbie....I just want to get it right the first time so I do not have to do it again!

[Steve93Talon]

I've never used a 20g with the 06 wheel, but we have set up Tort's car with a 20g that had the 05H wheel and then swapped it with a new cartridge with the 06H wheel and Bullseye housing. It spooled maybe a couple hundred RPMs slower at most, and definitely pulled a bit harder up top, but you could attribute either of those facts to the larger scroll on the Bullseye housing. All in all, the 05H setup was still to this day the most fun street/strip setup I've ever driven on a DSM. It hit so ridiculously hard it was scary. He went 11.02 @ 126.79 on the 05H hotside, and was never able to beat those numbers with the 06H due to drivetrain problems.

The 06 wheel is kinda a redheaded stepchild of the 06H, similar inducer/exducer size, but lower flow rating. The "H" wheels are the performance wheels and are always what you see in the faster hybrid turbos (Red, Green, TTX "street/strip" 20g, bigger Franks,...). I had a Frank2 with an 06 wheel and I hated it, worst turbo I ever owned. If your 05H wheel is clipped, that's definitely the way I'd go.

[jusmx141]

Haha the 05H isn't clipped, but it can be!

I always wondered why the only 20G's that Buschur sells has a TD05H turbine. It obviously works for them!

This is exactly the type of info I was looking for. Thanks so much for your input.

[Jon Lane]

Newb question: How much of this, if any, would translate to the 18G series?

[hopwoodp]

Originally Posted by Jon Lane

Newb question: How much of this, if any, would translate to the 18G series?

I don't really think it would be a good idea to use anything larger than a td05h turbine wheel on an 18g. The EvoIII turbo is not much smaller than the 18g and it works perfectly with the o5h wheel.

Thats why you have the question about what is better for the 20g turbo. The 05h wheel gives you faster spool but, not as much power as the o6h wheel puts out. The o6h wheel is good for the top end(but, also slower spool).

In my opinion the 06h turbine wheel is good for drag racing/high rpm runs. Where as the 05h is the best for street driven turbos.

But, it all depends on what the driver wants. Where do you want your power to come on, mid range or top end?

[TurboAnything]

The 05h is the setup i tell everyone to run as it make sick power very low in the rpm's. I just finished a tune on my buddies tdo5h-20g and when he hits boost at 3500rpm it lites all 4 tires up!

[hopwoodp]

Thats what I'm aiming for. Why else put a 2g head on a 6 bolt block? =)

[Jon Lane]

Originally Posted by hopwoodp

In my opinion the 06h turbine wheel is good for drag racing/high rpm runs. Where as the 05h is the best for street driven turbos.

But, it all depends on what the driver wants. Where do you want your power to come on, mid range or top end?

Street all-2G 2.1, widest possible powerband (but would rather stretch it out on top a little than on the bottom) and not more than 400Hp. I need a Mits-style housing. I'm thinking 18G-5H because the big 16 might gasp a little up high.

[dsm-onster]

Originally Posted by hopwoodp

I don't really think it would be a good idea to use anything larger than a td05h turbine wheel on an 18g. The EvoIII turbo is not much smaller than the 18g and it works perfectly with the o5h wheel.

Thats why you have the question about what is better for the 20g turbo. The 05h wheel gives you faster spool but, not as much power as the o6h wheel puts out. The o6h wheel is good for the top end(but, also slower spool).

In my opinion the 06h turbine wheel is good for drag racing/high rpm runs. Where as the 05h is the best for street driven turbos.

But, it all depends on what the driver wants. Where do you want your power to come on, mid range or top end?

I don't agree. I feel the tdo5H wheel is a bottle neck for the evo3 16g. It certainly was for my 18G. Especially w/ a stock 7cm^2 housing. Also I feel the stock 6 cm^2 housing is a bottleneck for the 14B wheel. I've seen this wheel do MUCH better than predicted when swapping to a BEP housing. The small 16G coupled w/ a TD05H 7cm^2 turbine is perfect, IMHO. The compressor cannot out flow the turbine. Nor is there any unneccesary spool time.

What evidence do you have that the 18G isn't worthy of of such a hotside? I'm curious. I've seen great results even considering I ran the small td05H wheel. I've seen an 18G outflow and totally out perform any level anyone would aspire an Evo3 16G to reach. It makes sense, too. As the 18g inducer is closer in size to the 20g than the evo3 16g. Thus it "grabs" much more air which leads to its ability to flow much more. All three turbos have the same exducer diameter (which primarily affects compressor efficiency at a particular boost).

I think the BEP housing w/ an TD05H wheel is the minimum small I'd go w/ a 20G compressor. I saw huge results going to BEP housing on my 18G. Much more flow up top. Lag was there but FAR worth it. I suspect that a 20G wheel w/ an even bigger inducer ("grabs" even more air) would benefit from the needed flow. I think a TD06H wheel w/ a 7cm^ housing will flow a bit more (note: fp green and fp red). And is a good compromise of spool and top end to stretch out the legs of the 20g wheel.

[spendone]

Ive had the Bushcur 20G on my 1g previously. My car ran 11.6 on pump gas (daily driven tune). I will say by far, that was probably one of the best turbos I have ever owned to this day.

[hopwoodp]

Dsm_monster, I'm not talking about the max potential of the turbo, what I am saying is that the o5h wheel is what I would prefer for Street use. If it was all about the track then o6h it is.
I guess you didn't understand that part. Also, the 18g is too close between the EvoIII and 20g that to me it seems almost pointless to just go to an 18g and not go right to the 20g.

Like I said before, its all up to the driver.

[dsm-onster]

Originally Posted by hopwoodp

Dsm_monster, I'm not talking about the max potential of the turbo, what I am saying is that the o5h wheel is what I would prefer for Street use. If it was all about the track then o6h it is.
I guess you didn't understand that part. Also, the 18g is too close between the EvoIII and 20g that to me it seems almost pointless to just go to an 18g and not go right to the 20g.

Like I said before, its all up to the driver.

I understand the advantages of the o5h wheel for street use. I feel the 7 cm^2 housing si still too small for the 05H wheel for the street if you decide to run a compressor wheel larger than the evo3 16G. It's jsut my opinion, but why run such a high flowing wheel w/ out looking at a hotside upgrade from a small 16g turbine? The td05h 7 cm^2 turbine 18G spools INSANELY fast considering the flow capability of the compressor. The 18G has it's place. It flows mcuh more than an evo3 16G and a bit less than a 20G.

Being there's such a significant flow difference between the evo3 16G and the 20G compressor wheels, I'm not understanding what you are saying about "too close". . . .

[hopwoodp]

Originally Posted by dsm-onster

I understand the advantages of the o5h wheel for street use. I feel the 7 cm^2 housing si still too small for the 05H wheel for the street if you decide to run a compressor wheel larger than the evo3 16G. It's jsut my opinion, but why run such a high flowing wheel w/ out looking at a hotside upgrade from a small 16g turbine? The td05h 7 cm^2 turbine 18G spools INSANELY fast considering the flow capability of the compressor. The 18G has it's place. It flows mcuh more than an evo3 16G and a bit less than a 20G.

Being there's such a significant flow difference between the evo3 16G and the 20G compressor wheels, I'm not understanding what you are saying about "too close". . . .

Ok, I see what your saying. Its just from the flow maps and other misc stuff. And yeah, some of it is hear say. But, whatever. You made a good point. I know the 18g is still out there for a reason so, I'm not doubting you. Thanks for the positive input.

[TurboAnything]

The tdo5h-20g car i just built has a 6cm housing ported massive and it's making well over 400hp at 24psi. And its spools full boost at 3500rpm. it feels like there is little more to gain so we are installing a dry nitrous kit spraying into the hot sie of the intercooler.

[dsm-onster]

Originally Posted by hopwoodp

Ok, I see what your saying. Its just from the flow maps and other misc stuff. And yeah, some of it is hear say. But, whatever. You made a good point. I know the 18g is still out there for a reason so, I'm not doubting you. Thanks for the positive input.

Oh it's truely not your fault. Seveal years ago anyone stating that a evo3 16G can deliver enough for 400whp or a 20G can spool under 3500 rpms (in certain cases) would be going agains what literally thousands of others say. SO MANY people say what you've said about the 18G that it has ceased being hearsay and is more something else. It's certainly not you that started such hearsay. Everyone says it.

We ALL learn new details on this forum all the time. See below . . .

[dsm-onster]

Originally Posted by TurboAnything

The tdo5h-20g car i just built has a 6cm housing ported massive and it's making well over 400hp at 24psi. And its spools full boost at 3500rpm. it feels like there is little more to gain so we are installing a dry nitrous kit spraying into the hot sie of the intercooler.

WOW! I had never heard of a 6cm^2 housing flowing so much. That housing is almost always coupled w/ the 05H wheel. And I've thought that both together was too small for even the 14B. . .

Why not consider a 7cm^2 housing? The spool would likely be about 200-300 rpms later at the most. I've seen your same turbo sporting a 7 cm^2 housing spool under 3800 rpms and flow enough for 450 hp.

. . . THEN spray

[jusmx141]

Here's a new twist:
Do you guys think an unclipped TD05H turbine with the Bullseye Monster exhaust housing (8.5cm2, I believe) would flow roughly the same as a clipped TD05H turbine with a Mitsu 7cm2 exhaust housing?

[dsm-onster]

How much of a clip?

I can't give any logs of BEP vs clipped wheel, but I did see good results upgrading to the BEP housing from a 7cm^2 housing w/ an unclipped turbine. I sold the setup after my BS belt went out. But I loved the setup. I pulled great up top (surprised me) and I didn't "feel" any loss down low. There was an increase in spool time. But certainly the overall VE helped my setup becasue of it "feeling" just as strong down low. I believe that a BEP housing on a TD05H wheel flows overall similarly to an 8cm^2 housing swap onto a TD05H wheel.