Outer Limits 4x4 Board

Hey guys have done a quick search and there seeems to be alot of debate over turbos on the forum however no real 100% recommendations, i have a fresh motor 12mm plunger on the pump and currently running the motor in with CT26 turbo which has bigger compressor wheel (running 12 pound).

Once done couple thousand k will change turbo and install big water to air intercooler however i would like to do the turbo at same time can you guys point me in the right direction not to many guys push them that hard in new zealand would love to have close to full boast just over 2k.

Was possibly looking at running a Holset HX35W with 12cm2 exhaust housing however not sure on the spool up time, have been told should be able to push it close to 30psi and still be within its effecency range.

Any Help much approicated would be cool to hear what some of you guys are running.

Thanks Glen

Garrett GT3071 with .64 hotside (I think they do a .64 hotside with these)

Ok sounds good when do these turbos come on with full boast? I was hoping to get something that was near full by 2k and then the fuel will keep it going through the rev range.

Also do you reckon i could push one of these close to 170rwkw?

Many Thanks Glen

TD05H 20g

What do you want to use the truck for?
Do you need fast spoolup and lots of low-mid range torque for towing and hills or do you want top end power to throw mud/sand around?

Basically you start with a torque or power goal, that gives you both the boost pressures you need and the flow the turbo has to do. From there you can pick the most suitable turbo.

My suggestion is find a car that performs like you want and go the same way as it . It will save you alot in the long run but don`t cut corners.I hear people bagging turbos and intercooler sizes and they are running crap manifolds/wastgate/intake and filter and the list goes on.You might also fall into the trap of expecting the impossable out of a turboed motor.All high boosted cars especially 4bs and high performance trucks should be driven whith an amount of "feel".Changing gears and sinking the boot is Not good for them at 800 rpm!! There are heaps of good running td 42s around but dont fall into the trap of just copying part of a setup and then be unhappy when it doesn`t work..it happens alot.. Cheers Billy..

The current truck with the ct26 and modified compressor side has excellent power up top once you hit 2200rpm it really kicks in and hauls no need to rev beyond 3000 although it easy will, was really trying to find something which will get me out of the hole quicker. The current turbo is a shocker offroad in low box even in normal driving you have to make an effort to rev it a bit more in first and second gear once you get going into 3rd and you have more load it spools better.

I have a large water to air intercooler/plenum which i will put on once i replace the turbo and would be aiming for 150rwkw plus happy to push up to 25psi.

Cheers

Big power and boost from low rpm are almost mutually exclusive goals. Unless you find a variable vane turbo of the right size or fit a compound set.

Holset do a variable vane turbo which several have used on smaller engines, but only autos to my knowledge. Autos of course can get away without low rpm boost.

damn figured it would end up with something like that what do you think would be the minimum size turbo i could get away with and still push 150 to 170rwkw? I have been told that the current CT26 is no good for any more than 18psi or something like that.

From reading all the posts garrett GT2876r or GT3071 or GT2540 all seem to be common however i don't actually know any body in nz running any of these with uprated pump to have a ride in.

Of the above is everybody in general runnign .64ar on the hotside? or does this push the egts up to much and the .84 end up being better?

Cheers

You want close to 200kw at the flywheel then?

Just crunching some numbers
190kw at 4000rpm, gives you 453Nm. Using an A/F ratio of 18, turbo efficiency of 60%, intercooler effectiveness of 60%, 80% VE, sealevel 20C etc.
You need to inject about 93 cc of fuel per 1000 shots.
You need about 23psi boost at the manifold, call it 28 at the turbo.
Total airflow is about 38 lb/min

Turbos that can do 28psi (PR 2.9) at 38 lb/min flow.
The 56 trim GT2871 does it just, the 48 trim 2871 is off the map.
The 2876 is comfortably on the map. No point in going bigger.

But this is just one point on the map.

i thought you needed a fair bit more than 93cc per 1000 pump revs to make 200 flywheel kw

tim75b wrote:i thought you needed a fair bit more than 93cc per 1000 pump revs to make 200 flywheel kw

The above figures are for 190kw at an efficiency of 300 g/kwh. I'd hope the TD42T can do that, other engines can produce about 30% more power off the same fuel and rpm.

Ok guys let me know what you think of the following turbo specs my pump will flow 115cc 1000 shots its a gt2871 using .64 rear housing:

Also would appricate inout on whether to bother with the ball bearing core or go for a non ball bearing turbo.

Compressor Wheel Minor Diameter: 52.70mm
Compressor Wheel Major Diameter: 76.00mm
Compressor Wheel Trim: 48
Compressor A/R: 0.70
Turbine Wheel Minor Diameter: 46.90mm
Turbine Wheel Major Diameter: 53.80mm
Turbine Wheel Trim: 76
Turbine A/R: 0.64
Recommended Horsepower Range: 280-480 hp
Recommended Displacement Range: 1.8L - 3.0L


Cheers Glen

Why don't you contact Aaron smythe in Rotorua regarding turbo work or Tauranga diesel and turbo (I think thats their name). They know what their doing regarding the TD42 and what they are capable of doing. A local T3/T4 was getting the specs you were talking about from memory.

Swamped wrote:Why don't you contact Aaron smythe in Rotorua regarding turbo work or Tauranga diesel and turbo (I think thats their name). They know what their doing regarding the TD42 and what they are capable of doing. A local T3/T4 was getting the specs you were talking about from memory.

The problem with T3/T4 clone turbos is the complete lack of performance data on them. They can't provide compressor maps and even if they did, could they be relied on?
For that reason alone the real brands (garrett, holset, Schwitzer etc) are always the pick.
For a low boost application you can get away with anything, but when you start pushing towards 30psi boost turbo matching becomes quite important.

Swamped i know Aaron personally (he did my pump) and have talked to him in detail about this he runs a geninue garrett turbo on his tuck the cheaper ones don't have correct trust washer and fail at higher boast (happened on my silvia running 18pound) i do beliebe you can retro-fit the garrett parts however but you would never know if the shafts or impellors are of suitable qualility.

His turbo still comes in a little late for my licking and i'm trying to see what everybody else is running and recommended.

Thanks however might try the guys at tauranga

IMO stay away from roller bearing. they are over rated and dont last.

The problem is EVERYBODY always gets tempted to run more boost than what the turbo is originally intended to do.

My 2860RS lasted just over a year and it was stuffed (23psi max). It would surge constantly. stick with mitusbishi, holset etc. much stronger turbo and costs less than $100 for a rebuild kit. They are also cheaper to buy in the first place.
The generic garrett turbos are not designed for diesels.

Please feel free to shoot me down. This is my opinion based on everything i have been learning about turbos.

Cheers

uzdnabuzd wrote:IMO stay away from roller bearing. they are over rated and dont last.

The problem is EVERYBODY always gets tempted to run more boost than what the turbo is originally intended to do.

My 2860RS lasted just over a year and it was stuffed (23psi max). It would surge constantly. stick with mitusbishi, holset etc. much stronger turbo and costs less than $100 for a rebuild kit. They are also cheaper to buy in the first place.
The generic garrett turbos are not designed for diesels.

Please feel free to shoot me down. This is my opinion based on everything i have been learning about turbos.

Cheers

I'd agree with you there. Journal bearing turbos are a lot more robust than roller bearings and more tolerant of oil quality issues.
The GT2860RS is a low boost turbo for petrol ricers, it's never going to play nicely with high boost. There are Garrett's designed to run at higher pressure ratios, Holset only make diesel turbochargers so all their turbos are designed for higher boost. Schwitzer (aka Borg Warner, KKK etc) also make turbos designed for high boost. MHI like garrett make a whole range of turbos for different applications, but information on them is harder to find that garrett.

KiwiBacon wrote:

uzdnabuzd wrote:IMO stay away from roller bearing. they are over rated and dont last.

The problem is EVERYBODY always gets tempted to run more boost than what the turbo is originally intended to do.

My 2860RS lasted just over a year and it was stuffed (23psi max). It would surge constantly. stick with mitusbishi, holset etc. much stronger turbo and costs less than $100 for a rebuild kit. They are also cheaper to buy in the first place.
The generic garrett turbos are not designed for diesels.

Please feel free to shoot me down. This is my opinion based on everything i have been learning about turbos.

Cheers

I'd agree with you there. Journal bearing turbos are a lot more robust than roller bearings and more tolerant of oil quality issues.
The GT2860RS is a low boost turbo for petrol ricers, it's never going to play nicely with high boost. There are Garrett's designed to run at higher pressure ratios, Holset only make diesel turbochargers so all their turbos are designed for higher boost. Schwitzer (aka Borg Warner, KKK etc) also make turbos designed for high boost. MHI like garrett make a whole range of turbos for different applications, but information on them is harder to find that garrett.

As a turbo rebuilder turbos are like candy and boiled lollies, the roller bearing is the candy, looks good tastes good but they are for kids who wanna play,sleeve bearing holsets,MHI,etc are boiled lollies, dont look so good people dont talk about them alot but they are robust and last for ages and you can always rely on them.

A T2 flange turbo should never be anywhere near a 4.2 litre engine that does in excess of 4000rpm, think about how much boost you really want to run and go from there because as some have stated you WILL up it and the turbo will be the first to suffer.

UGOTNUFN wrote:A T2 flange turbo should never be anywhere near a 4.2 litre engine that does in excess of 4000rpm

Why not? Garrett make some rather large T2 flanged turbos.

KiwiBacon wrote:

UGOTNUFN wrote:A T2 flange turbo should never be anywhere near a 4.2 litre engine that does in excess of 4000rpm

Why not? Garrett make some rather large T2 flanged turbos.

The frame size just doesnt support the engien CFM regardless of how big a turbine wheel A/R they try to glue onto the T2 flange frame.

UGOTNUFN wrote:The frame size just doesnt support the engien CFM regardless of how big a turbine wheel A/R they try to glue onto the T2 flange frame.

Lets look at a 3071R. The map extends to pressure ratios of 3.5 (up to 37psi boost) at 37 lb/min and reaches to a max flow of 47 lb/min at a PR of 2.7 (25psi).

A 4.2 at 4000rpm with 80% VE, 60% Intercooling, 65% efficient turbo and 25psi consumes just under 40 lb/min of air. That's producing around 200kw.
That's still safely on the map and will stay on the map at 4,500rpm. It's not the biggest turbo with a T2 flange either.
If you want more than that, you're straight into compound turbo territory.

Put simply, a T2 flange isn't the bottleneck and even in a compound setup isn't a bottleneck. Also think about this, more boost and pressure does not change the velocity or volume flow rates through the engine.
It changes the density, but volume flows and velocities are comparable to a NA engine.

KiwiBacon wrote:

UGOTNUFN wrote:The frame size just doesnt support the engien CFM regardless of how big a turbine wheel A/R they try to glue onto the T2 flange frame.

Lets look at a 3071R. The map extends to pressure ratios of 3.5 (up to 37psi boost) at 37 lb/min and reaches to a max flow of 47 lb/min at a PR of 2.7 (25psi).

A 4.2 at 4000rpm with 80% VE, 60% Intercooling, 65% efficient turbo and 25psi consumes just under 40 lb/min of air. That's producing around 200kw.
That's still safely on the map and will stay on the map at 4,500rpm. It's not the biggest turbo with a T2 flange either.
If you want more than that, you're straight into compound turbo territory.

Put simply, a T2 flange isn't the bottleneck and even in a compound setup isn't a bottleneck. Also think about this, more boost and pressure does not change the velocity or volume flow rates through the engine.
It changes the density, but volume flows and velocities are comparable to a NA engine.

Next time you try this have a quick measure of turbine back pressures!!!!

UGOTNUFN wrote:Next time you try this have a quick measure of turbine back pressures!!!!

Turbine backpressure is due to the turbine operating conditions and the scroll feeding it. Not the flange connecting it to the manifold.

Simple check, there are more square cm through a T2 flange than there are at the exit of the GT30 turbine. The exit from the turbine is spewing expanded gas, far bigger volume and velocity than through the manifold flange.

KiwiBacon wrote:

UGOTNUFN wrote:Next time you try this have a quick measure of turbine back pressures!!!!

Turbine backpressure is due to the turbine operating conditions and the scroll feeding it. Not the flange connecting it to the manifold.

Simple check, there are more square cm through a T2 flange than there are at the exit of the GT30 turbine. The exit from the turbine is spewing expanded gas, far bigger volume and velocity than through the manifold flange.

Totally understand BUT reducing the flange size is asking for trouble further back in the chain.

Simply put, i just dont agree with it and wont do it.

Just my 2c

Nah, I had a MTQ Mitsubishi Turbo kit fitted and had major heating issues, am now running Garrett Ball Bearing with more boost than mitsi and have not got EGT's over 500 up a hill flat out. where as the MTQ hit over 600 regularly and easily. Also MTQ kit was dyno'd before and tuned after fitting. Current Garrett Setup has not been on dyno since fitted and tuned. The dyno guys claim it is running way to much boost unintercooled which causes too much heat but that clearly isn't the case with the EGT's I'm getting!!

David

moddedgu wrote:Nah, I had a MTQ Mitsubishi Turbo kit fitted and had major heating issues, am now running Garrett Ball Bearing with more boost than mitsi and have not got EGT's over 500 up a hill flat out. where as the MTQ hit over 600 regularly and easily. Also MTQ kit was dyno'd and before and tuned after fitting. Current Garrett Setup has not been on dyno since fitted and tuned. The dyno guys claim it is running way to much boost unintercooled which causes too much heat but that clearly isn't the case with the EGT's I'm getting!!

David

You have lower EGT's becuase your running higher boost, how much are you running by the way?

Rhysta wrote: You have lower EGT's becuase your running higher boost, how much are you running by the way?

20 Why???

moddedgu wrote:Nah, I had a MTQ Mitsubishi Turbo kit fitted and had major heating issues, am now running Garrett Ball Bearing with more boost than mitsi and have not got EGT's over 500 up a hill flat out. where as the MTQ hit over 600 regularly and easily. Also MTQ kit was dyno'd before and tuned after fitting. Current Garrett Setup has not been on dyno since fitted and tuned. The dyno guys claim it is running way to much boost unintercooled which causes too much heat but that clearly isn't the case with the EGT's I'm getting!!

David

your egts has stuff all to do with the turbo brand..................................

moddedgu wrote:Nah, I had a MTQ Mitsubishi Turbo kit fitted and had major heating issues, am now running Garrett Ball Bearing with more boost than mitsi and have not got EGT's over 500 up a hill flat out. where as the MTQ hit over 600 regularly and easily. Also MTQ kit was dyno'd before and tuned after fitting. Current Garrett Setup has not been on dyno since fitted and tuned. The dyno guys claim it is running way to much boost unintercooled which causes too much heat but that clearly isn't the case with the EGT's I'm getting!!

David

Oh how misguided we are,the setup you had will record approx 70 degree higher egt's post turbo than a garrett on the same tune. For starters you are running way more boost than the MTQ setup would have been setup for hence the lower egt's also.

What you have described has absolutely nothing to do with the brand of turbo you have now.