Turbo recomendations

[Jdeac]

Hi all. My build is in the project section.

I'm getting a little confused with all these different makes/types of turbos. And all the numbers.

If someone could point me in the right direction would be great.

I have a loan of a turbo. But the flange is not quite right. Easy enough to sort.

The manifold I have is of t3 type

Motor spec b12 base

Ported head, adjustable cam sprockets, busa rods/pistons, base spacer, knifedged crank, lock up etc etc.

Looking to find either a knackered turbo or cheep as. To check clearances etc. And if the manifold I have will work.

All help appreciated 

[Arttu]

One very crucial piece of info is missing: How much power you want?

[Jdeac]

Forgot to say it's also all the numbers of hot and cold side that baffle me. 

Seen holset, garret, pression turbos etc.

Holset He221w as a recmendation but the there is 6,7,8 inch housings

Garret gt2860

Just really confused lol don't take alot mind you!!

[Jdeac]

8 minutes ago, Arttu said:

One very crucial piece of info is missing: How much power you want?

As much as I can. The occasional strip action. But will mainly be a road bike. But it's always nice to have it there if you want it. If that makes sense

[Jdeac]

So a garrett with an ar 50 cold side and ar63 hot for example

[Jdeac]

And yes some of you know I run pyro drag bike. But I did not build this. Turbo stuff is all new to me

[Arttu]

1 hour ago, Jdeac said:

Forgot to say it's also all the numbers of hot and cold side that baffle me.

IMO wheel sizes and housing AR numbers aren't very useful since they vary between manufacturers. Meaning that for example 50mm compressor from Garrett might be very different than 50mm from Holset. So they can be used mostly to compare turbos from the same product family. Of course if you happen to have some mystery whizzler without any info then you can get some idea from the wheel sizes.

[Jdeac]

More confused now. I would rather not go down the turbo kit route. But be able to work things out myself. And source parts etc separately etc.

I would just like to know what route to take with the turbo etc. 

 

Edited November 22, 2022 by Jdeac

[Arttu]

14 hours ago, Jdeac said:

As much as I can. The occasional strip action. But will mainly be a road bike. But it's always nice to have it there if you want it. If that makes sense

Not the best possible answer You can get almost as much power as you want, up to 600hp or so. But sizing the turbo for bigger power comes at cost, meaning later spool-up, bigger lag and worse efficiency at lower power. So it's better to set some realistic goal for maximum power and select the turbo for that.

To get the discussion going let's pick some examples, starting from low end of the price range.

• Mitsubishi TD05-20. Actually this is cheap only because there are plenty of Chinese copies on the market that seem to work just fine... Maximum power maybe around 350hp. To give some idea here is a dyno graph from a very similar engine that you have, 1 bar boost.
• Holset HX35. Not the most modern design so spools up a bit slowly and maybe doesn't make the best power for boost. But capable for way over 400hp especially at higher boost levels. Size is pretty huge. Again dyno example from very similar engine, 1.3bar boost.
• Garrett GT2871R. Over 400hp. Ball bearings, spools up pretty much like the Mitsu TD05-20, most likely makes more power at the same boost. Physically smaller than the Holset HX35.
• Xona Rotor XR 4951S. Maximum power probably around 500hp. I don't have first hand experience about this exact model but based on some bigger one these are pretty much the best shit that you can get. Makes really good power for boost and spools up well compared to the power capacity. Very lightweight too. But mucho $$$...

Edited November 23, 2022 by Arttu
typos...

[Jdeac]

So (yes I've had a beer) my drag bike uses an ihi rhf5 turbo. Intercooler on race fuel pulls 20psi of boost at a claimed approx 320 bhp. Goes full boost in 4th. Engine is stock gsxr1100 busa pistons. Stock everything else apart from clutch as that  I'm aware of.

The motor I have in my build is a higher spec. (Not built by me)  should be able to make good numbers. But as its for the road (ish) 

Your saying a td05 20t (not looked into that yet) would get me in the high 200's able to turn it down (boost wise) for the road. 

Lots if other options I guess. Just trying to work things out.

Thanks for your input so far

 

[Jdeac]

Td04/5 are 3 bolt flange correct...or can any turbo have any flange?

I don't want to sound thick or anything. Just the post are easyier to understand. On hear maybe. Than reading things online

[Fredrik_Steen]

If you can afford it I would go ball bearing, journal's flow a lot of oil (that oil you want to keep in the crankshaft bearings)

Learn how to read compressor maps, I like this channel 

They have several videos on the topic 

[Jdeac]

Just now, Fredrik_Steen said:

If you can afford it I would go ball bearing, journal's flow a lot of oil (that oil you want to keep in the crankshaft bearings)

Learn how to read compressor maps, I like this channel 

They have several videos on the topic 

Appreciate your input. And I have watched loads about turbos etc. I'll check out the one above. 

 

[Arttu]

9 hours ago, Jdeac said:

Your saying a td05 20t (not looked into that yet) would get me in the high 200's able to turn it down (boost wise) for the road.

Yes, TD05-20 or TD05-16 should be a good basic choice for approximately 200-350hp power range. If you don't need over 300hp another option could be TD04-16 that should spool up earlier and provide better mid rpm power.

Just be aware that it can be somewhat tricky to get low boost, below 0.6-0.8 bar, with the internal wastegate on these. Standard actuators on these are usually around 0.8 bar. The actuator can be changed to lower pressure one but then you will probably face boost creep since the gate can't flow enough to keep boost down. This can be improved by porting the wastegate hole but still you probably will struggle to get below 0.5 bar at high rpm.

9 hours ago, Jdeac said:

Td04/5 are 3 bolt flange correct...or can any turbo have any flange?

Availability of flange types depends on what kind exhaust housings have been made for that particular turbo. Typically there are few different flange types available for each turbo model. Aftermarket performance turbos typically use 4-bolt T25/T3/T4 flanges or round v-band flanges. OEM car turbos use these too but in addition there are numerous car specific flange types like those 3-bolt ones.

TD05 turbos seem to be available with both car specific (Subaru) 3-bolt flanges and generic T25/T3 flanges.

 

 

[Gixer1460]

The two responders here are a damn sight brighter and cleverer in respect of this stuff and understand the numbers - something that has defeated me, so i'm a 'try it and see' type for development LOL! If I do another build, I will deffo use a BB type core, Maybe Garrett 28R or 30R based - its the housings and wheels where the secret sauce is hidden so listen to the two guys above!

[Jdeac]

8 minutes ago, Gixer1460 said:

The two responders here are a damn sight brighter and cleverer in respect of this stuff and understand the numbers - something that has defeated me, so i'm a 'try it and see' type for development LOL! If I do another build, I will deffo use a BB type core, Maybe Garrett 28R or 30R based - its the housings and wheels where the secret sauce is hidden so listen to the two guys above!

This is what I'm trying to work out the housing sizes. So I can find a scrap or cheep turbo for mockup. Clearance checks etc. Physical size and the number.

All the info above is great. Some hard to understand. We'll at the moment.

I get the basics but say gt2860r OK it's then the numbers (ar)  where I'm getting lost. .60 .70 .80 hot side cold side

Like I was told by a turbo builder. Holset he221w good for 280bhp but then there is 5,6,7cm etc sizes

I'll keep watching. And try grasp it.

[Arttu]

57 minutes ago, Gixer1460 said:

The two responders here are a damn sight brighter and cleverer in respect of this stuff and understand the numbers - something that has defeated me, so i'm a 'try it and see' type for development LOL! If I do another build, I will deffo use a BB type core, Maybe Garrett 28R or 30R based - its the housings and wheels where the secret sauce is hidden so listen to the two guys above!

Well, there is still plenty of "try and see" even after munching all those numbers But knowing the basics and doing your homework can improve your chances significantly.

[Arttu]

53 minutes ago, Jdeac said:

I get the basics but say gt2860r OK it's then the numbers (ar)  where I'm getting lost. .60 .70 .80 hot side cold side

Like I was told by a turbo builder. Holset he221w good for 280bhp but then there is 5,6,7cm etc sizes

I'll keep watching. And try grasp it.

Typically compressor and turbine wheel sizes are fixed within a turbo model. And usually compressor housing is fixed too. But for the turbine housing there are often different size options. Some manufacturers use A/R ratio (like 0.84) and some turbine throat area (like 8cm2) to specify the size.

Turbine housing options can be thought as fine tuning for the base turbo model selection. Basically bigger housing means lower exhaust pressure and hence more power at the same boost. As flip side it also means later spool up and slower response.

[Fredrik_Steen]

8 hours ago, Jdeac said:

This is what I'm trying to work out the housing sizes.

I get the basics but say gt2860r OK it's then the numbers (ar)  where I'm getting lost. .60 .70 .80 hot side cold side

Like I was told by a turbo builder. Holset he221w good for 280bhp but then there is 5,6,7cm etc sizes

I'll keep watching. And try grasp it.

It's hard to say what a turbo are "good for" It depends on your engine combination. In your case I would calculate with a 120hp engine. At one bar it will produce 240hp. Two bar = 360hp if the exhaust back pressure are kept in check and the intercooler can support the heat. Roughly estimations, but gives you a idea when you check compressor maps

[Jdeac]

8 minutes ago, Fredrik_Steen said:

It's hard to say what a turbo are "good for" It depends on your engine combination. In your case I would calculate with a 120hp engine. At one bar it will produce 240hp. Two bar = 360hp if the exhaust back pressure are kept in check and the intercooler can support the heat. Roughly estimations, but gives you a idea when you check compressor maps

I'm still trying to absorb the info on maps etc. The previous owner of the motor I have claimed it was around the 150 ish bhp mark. Before going low comp for turbo etc.

I don't have an intercooler on my build. But have been looking at the possibility of having one. 

What's the thoughts on this turbo??

[Fredrik_Steen]

1 hour ago, Jdeac said:

I'm still trying to absorb the info on maps etc. The previous owner of the motor I have claimed it was around the 150 ish bhp mark. Before going low comp for turbo etc.

I don't have an intercooler on my build. But have been looking at the possibility of having one. 

What's the thoughts on this turbo??

I'm guessing it's the maxspeeding brand you are looking at. It's cheap 

Looking at similar compressor maps I don't think it's the best choice out there for your application. 

If you still have stock b12 camshafts in the engine I think 150ish are a bit optimistic. 

[Jdeac]

5 minutes ago, Fredrik_Steen said:

I'm guessing it's the maxspeeding brand you are looking at. It's cheap 

Looking at similar compressor maps I don't think it's the best choice out there for your application. 

If you still have stock b12 camshafts in the engine I think 150ish are a bit optimistic. 

I know the cam sprockets are adjustable. Might pull the cover tomorrow and see what cams are in it. This will be another question!! All this is new to me!!

[Arttu]

8 hours ago, Fredrik_Steen said:

I'm guessing it's the maxspeeding brand you are looking at. It's cheap 

Looking at similar compressor maps I don't think it's the best choice out there for your application.

Care to explain? Based on maps that I found it might be slightly on large side, depending on which map you believe. But still  my flow estimations for 0.5 to 1.5 bar boost range seems to fit quite nicely on the map. And in practise it seems to work fine too. Although, if good response is preferred over maximum power a smaller TD06-16 variant might be a better choice.

Of course if you mean the absolutely best by "best choice" I agree It's a budget choice after all, especially when using those cheap copies. But most likely works just fine any ways.

[Fredrik_Steen]

4 hours ago, Arttu said:

Care to explain? Based on maps that I found it might be slightly on large side, depending on which map you believe. But still  my flow estimations for 0.5 to 1.5 bar boost range seems to fit quite nicely on the map. And in practise it seems to work fine too. Although, if good response is preferred over maximum power a smaller TD06-16 variant might be a better choice.

Of course if you mean the absolutely best by "best choice" I agree It's a budget choice after all, especially when using those cheap copies. But most likely works just fine any ways.

Yes i based my recommendation on this map ( I added two red dots). And a estimation that he will be pushing around 2 bar to get 360ish hp without intercooler.  I think this turbo are more suited for a stronger/more tuned base engine 

[Arttu]

Hmm, not sure if I can follow your thoughts. What's the another red dot on the bottom of the map?

All right, let's do some more compressor map analysis. (Warning, some numbers and theory stuff ahead!)

First let's see what kind maps we can find for the TD05-20. I found basically two different maps from the net. Both are actually for TD06-20G but since the compressor side is the same (20G) they should be fine. Another one uses kg/s mass flow and another one CFM volume flow.  The maps are shown here side by side. By closer look it seems that the maps itself are the same and another one is just converted to different units. I'm pretty sure that the kg/s map is the original one and the CFM one is probably converted by some random guy. Also it looks like the conversion is somewhat "optimistic". So let's use the kg/s map for analysis.

By quick look on the map we can see that highest presure ratio what it can reach is 2.9 which means 1.9 bar boost in typical conditions. So yes, if you need over 2 bar boost this clearly isn't the right turbo. Maximum mass flow is 320g/s and 300g/s can be reached with boost between 1.0 - 1.6 bar. Rule of thumb for converting mass flow to engine power is that 1hp needs about 0.8g/s. This can naturally vary between the engines but it's accurate enough for this kind purposes.  So maximum realistic power for this turbo would be around 375hp.

Then we are going to cheat a little bit and use real life data to estimate where we would land on the map with this 1216cc oil cooled engine. Here I have dyno graphs from a Bandit using this turbo, 1.0 bar and 1.4 bar. The engine was 1186cc, ported head, GSX-R1100 cams. The pistons were flat tops and 2mm spacer plate was used so compression was pretty low. No intercooler but water injection was used.

At 1 bar full boost was reached around 6500rpm and engine made there about 185hp. Maximum power slightly under 250hp. Mass flows respectively 148g/s and 200g/s. At 1.4 bar full boost at 7000rpm and 240hp, max power about 290hp, mass flows 192g/s and 232g/s. I don't have graphs for lower boost but for 0.5 bar I would guess full boost at 6000rpm / 150hp and max. around 200hp. Mass flows 120g/s and 160g/s.

As side note these power figures were a bit lower than I would expect in ideal case. Probably due to low compression and bad combustion chamber shape. So it's possible that actual air flow figures were slightly bigger than estimated here.

So finally we just need to plot these numbers on the map. 0.5 bar shown in blue, 1.0 bar in green and 1.4 bar red.  So here we can see that on all these boost levels we are nicely on the map and even on pretty good efficiency area. If the engine can be made to flow better, for example by adding an intercooler, the operating points will shift to the right to higher flow. And there is still some flow reserve available for that.

So I would still say that this turbo suits pretty well for a Bandit/GSX-R engine around 1200cc when using boost between 0.5 and 1.5 bar. Maximum power will depend on how well the engine flows. I guess about 320hp should be possible without intercooling if the engine is done right. With intercooler even over 350hp should be doable.

Edited November 24, 2022 by Arttu