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td42 best turbo

Tech Talk for Nissan owners.

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Re: td42 best turbo

Post by Northside 4x4 »

I honestly cant recall the turbine A/R, I think it was the .86 but only 99% sure of this.

I think with regards to the fuel ratio, i think alot of people overestimate the VE of the old 4.2's when they are doing fuel calcs. You have to remember the standard manifold on these things have more than 30% difference in flow between the best and the worst. So using a VE of say 72% might be applicable to 2 of the cylinders, the other 4 would be done considerably on that.

I should have done a coast down and measured engine torque, but its not something i really ever bother doing, i just measure before and after in % and thats good enough for me.

I have found that particular setup still has a good amount of room left for the power hungry.
The dyno graph below is with the same turbo, slightly larger intercooler core.. but no other differences what so ever. Except more boost and more fuel, still no smoke though :)
Was about 20-21psi and 18:1 while on boost. Was very interesting to note, going all the way up to 28psi on this vehicle made no more power and did not lean out the fuel ratio at all. The little turbo is just well out of its efficiency range past about 20psi.

Image

Sorry for not having fuel and boost on this one, I would have to dig it up as this is quite a few years old now.
Red graph is standard, Blue is turbo/intercooler/exhaust/tuning etc.., green is with water/meth injection on.

Ramp rate is road speed per second of acceleration. Generally take your number of say 070, divide that by 10 and it give K's per second of allowable acceleration.
The dyno then measures how much force it must apply to the retarders to stop the vehicle accelerating any faster than this set rate.
So the lower you set it, the more load the engine is under.
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Re: td42 best turbo

Post by CustomTurbos »

Red60, I did do a dyno full dyno run, but like Northside4x4 said, if you use a inertia dyno on a TD, your in for a lousy graph, and for a power run, inertia is what I have available at the moment - but this is set to change. This is the reason I posted the vids with actual showing of kw @ wheels and showing tacho and boost in background, because while the dyno does the full power run on inertia mode, it does have a retarder which was used to show true torque by giving it a constant load. Using my available resources, thats the best I can do right at this moment. I have sent out a few turbos and customers will have them installed over the next 3-4 weeks. They will be tested on whatever their local tuning provider has, so chances are there will be a few that can do a loaded run and for the purposes of comparison, if they are a DD dyno, I will ask them to set the ramp to 070.

Maybe you didnt see the vids posted? 1.1Bar, 65kw @ wheels @ 1600rpm, 75kw @ wheels @ 1800rpm, 83kw @ 2000rpm @ wheels, peak kw just under 100kw @ ~ 3000rpm, all with no smoke. If a picture is worth a thousand words, whats a moving picture worth? For ~75cc or so on a 3.98L non intercooled DI engine, thats a great result. I am sure Northside would concur. Maybe I posted them on another forum. Look on youtube for "Ozholiday"

[/quote]

Dieslex, have you had any dyno feedback (or original data) on your modded ct26s,... as you have generally noted yourself, printouts like Northside has kindly provided, makes it easier for people like myself, who aren't super technical, to understand what's happening..... what it boils down to is Dieslex, I still want you (Dieslex) to post graphs like Northside has done, before and after with all possible data and comments..... in your thread of course ... enuf of my hijak....[/quote]
Last edited by CustomTurbos on Mon Apr 04, 2011 3:02 pm, edited 3 times in total.
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Re: td42 best turbo

Post by CustomTurbos »

@ Northside. Nice graph showing advantages of water/meth.

The best I have seen for the GT2860RS on TD42 was 580nm @ crank and 201hp @ wheels, 23-25psi, diesel only. Drove great, but it died (turbo).

Regarding the earlier graphs posted and your comments on VE, I notice that the AFR increases with rpm despite boost reducing with rpm and the fact that the VE would decrease from a best of ~95% to possibly as low as near 70%. I have looked a few times in detail and the AFR appeared to be measured on the run without the electronic boost controller fitted, so it is with the falling boost. Any comments on this, as it is counter intuitive.

As far as filling cylinders unevenly, it certainly is a case of having to design according to the lowest common denominator, so there could be little bit extra in there for a custom manifold design like the one in this thread. Did you measure the 30% difference - is is alot more than I would have thought. And if measured, was it with the manifold on the head? While the manifold itself might have a 30% peak flow difference from best to worst, it the flow through the valve is significantly less than the worst of the manifold ports (it will be), the actual impact on the flow through the valve will be far less significant.
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Re: td42 best turbo

Post by Northside 4x4 »

ok ill try and list responses in categorically, Sorry if this becomes a long post.
AFR increasing - None of the td42 graphs i have up there have electronic boost control fitted, only the 1hd-fte graph.
You are right in what you say about engine VE to a point. When you change the intake manifold on them, it is common for a given boost to give higher AFR's, as the lower flowing cylinders are now receiving the full amount of flow.
On a standard motor, with just the manifold change, the AFR usually goes from 24:1 at full throttle to 28-29:1 Thats a pretty huge jump, add an intercooler and its off the readable scale of 36:1

It changes the manifold pulse tuning to a different RPM, which does have an effect of changing engine VE. The only real way to measure this is through math's or on the dyno, we chose the latter in determining our final intake manifold design.
With the boost dropping off, a few things to note with this.
The engine picking up in VE% can cause this to some extent, turbine flow is approaching its choke point, exh manifold pressure is increasing, forcing the wastegate further open etc...
Ontop of that, as the boost is dropping. If you plot the engine against the compressor map. You can see it is falling back into its highest efficiency point once again of about 76% which reduces the temperature of the air.
And finally, as the boost tapers off it reduces pressure on the boost compensator diaphragm which reduces the amount of extra fuel it outputs.

Manifold was only measured, not on the head.
You are right in assuming valve flow is lower than the manifold. However, it is designed this way to ensure maximum air speed into the cylinder and also good swirl and tumble to spread the combustion fast. The venturi effect essentially.
So if manifold flow is down close to valve flow, you dont get that larger volume of air trying to squeeze through a narrow passage effect. Which essentially increases the air speed, and even if the flow is done some, the extra speed will pull more air through in a given time.

The absolute best way to see this first hand is in Engine Analyzer Pro, where it can calculate actual head port pressure dependent on valve and intake size. And show you in a graphical interface the movement of the air into the head.

65kw ATW with no smoke is a fantastic result no doubts about it. And it is bloody great to finally see another tuner that has adopted the smoke is stupid attitude. There are far to many wannabe tuners out there with no idea that are costing customers a fortune in fuel bills and repair bills AND! Giving the rest of us a bad name!

I look forward to seeing some graphs of various turbo's. No turbo will be the best forever, and im sure not everybody will agree which one is best at the time.
The only way the industry will move forward is to look at the data from other shops that are trying new things and not be to stubborn or pig headed about the results. Hell we used to sell hi-flow units, great at the time, garbage compared to anything else now.
I stand by the 2860 at the moment as it suits the needs of 90% of our customers better than any other turbo available to me (within a reasonable budget).

Also Dieslex - I am based just north of brisbane, so if any of your customers are in our area I am happy to tune the vehicle to what ever boost/fuel ratio you specify for testing purposes.

Cheers
Lindsay
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Re: td42 best turbo

Post by CustomTurbos »

Thats really interesting info. AFR measurements are critical. I would like to add air (mass) flow to that as well to be able to reality check the AFR readings and pump settings, but harder to implement.

What kind of inlet manifold changes are you referring to (on TD42 cutting plenum in half, increasing plenum volume...). Thats a nice change in AFR. Do you sell such a manifold?

If any of my turbos find there way on an engine near Brisvegas, I will send them over to you to dyno.

[quote="Northside 4x4"]ok ill try and list responses in categorically, Sorry if this becomes a long post.
AFR increasing - None of the td42 graphs i have up there have electronic boost control fitted, only the 1hd-fte graph.
You are right in what you say about engine VE to a point. When you change the intake manifold on them, it is common for a given boost to give higher AFR's, as the lower flowing cylinders are now receiving the full amount of flow.
On a standard motor, with just the manifold change, the AFR usually goes from 24:1 at full throttle to 28-29:1 Thats a pretty huge jump, add an intercooler and its off the readable scale of 36:1
Last edited by CustomTurbos on Mon Apr 04, 2011 4:11 pm, edited 1 time in total.
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Re: td42 best turbo

Post by CustomTurbos »

@ northside, which graph was for the 1HD-FTE you mention.

I didnt catch that before, I thought all posted graphs (in this thread) were for the TD42? If some of them are for the 1HD-FTE, considering there is a 15-20% difference is BSFC between the two engines, that raises a few more questions.

Maybe you are referring to the last graph?
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Re: td42 best turbo

Post by Northside 4x4 »

Yes, just the last graph showing only boost. Thats the 1hd-fte with electronic boost control, only posted it up to show the difference in boost ramp that can be achieved with it.

With the manifold yeah its basically cutting the top off it and making a larger plenum. Its not based purely on performance however as it is sold as a bolt on solution where people are still able to bolt the dipstick, earth straps etc.. up to, and use just about any type of intercooler they choose.
You could design something much better (such as Heath's old setup) But would be impractical to send out to customers from a business stand point.

Picture of the full intercooler manifold kit
Image

And on the car
Image

Manifolds are sold separately but are quite time consuming to make, so I sell them for around $400 exhange.
If your good with a TIG you could make one up yourself, but changing the plenum volume, does play a part in where the power is delivered as I said earlier.
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Re: td42 best turbo

Post by UGOTNUFN »

No matter how I look at that last graph I can't seem to get max torque any lower than 3000!

Correct me I'f I'm wrong
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Re: td42 best turbo

Post by Northside 4x4 »

I believe the way you are reading it is incorrectly.
The two red lines are power (intersecting about 100hp @ 3400rpm) and Torque (intersecting about 580lb @ 2800rpm) - Standard run.

The two blue lines are Power (intersecting about 180hp @ 3400rpm) and Torque (intersecting about 1050lb @ 1700rpm) - Turbo and Intercooler Fitted, and also 35" Mickey T ATZ Tyres fitted which drags the reading down somewhat.

The green lines are with water methanol switched on.
I know it makes the graphs hard to read when there is around 100% gain on them, the old power curve looks lower than the new torque curve lol
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Re: td42 best turbo

Post by jbates58 »

how does the DTS kit with the TD05 turbo rate for the patrol td42's? im looking at getting one in the next few weeks. and im not after a roller bearing turbo. will have a 3" ftraight through. any ideas of standard to turbo power and torque increses?

cheers

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Re: td42 best turbo

Post by Northside 4x4 »

I dont rate them very highly at all personally, im sure others will disagree.
With normal tuning you can expect around a 40% power/torque gain.

Ill look through my dyno folder tomorrow and dig out a few denco/dts/safari turbo install's and post up whats relevant.

Just out of curiosity though, why are you steering away from the roller turbo?
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Re: td42 best turbo

Post by chunks »

Great thread, keep it up fellas!
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Re: td42 best turbo

Post by jbates58 »

Northside 4x4 wrote:I dont rate them very highly at all personally, im sure others will disagree.
With normal tuning you can expect around a 40% power/torque gain.

Ill look through my dyno folder tomorrow and dig out a few denco/dts/safari turbo install's and post up whats relevant.

Just out of curiosity though, why are you steering away from the roller turbo?

from everything i have been told and read, a roller bearing turbo isnt as suited to a diesel (ot atleast a td42) due to something about the oil. and also, the fact that the cant be rebuilt if they shit themselves, and if the do shit themselves, they send bearings into your engine. whereas a journal can be rebuilt if need be, and will only send oil into the engine. i know which i'd perfer.

and yes while i do know that the rollers are sposed to spool quicker and whistle louder, i dont think i can justify the extra expense on one compared to a td05. unless i can be convinced otherwise.

this is a total minefield of a subject. i believe in doing things once, and that they are right first time, and that they will last the distance.

cheers

jbates58
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Re: td42 best turbo

Post by Northside 4x4 »

Im not 100% sure why people throw around the 'facts' that ball bearing turbo's are not suited to a diesel motor.
I have been using them since they have been around, and as I have said before have not had to warrant/replace/rebuild a single unit that was working within its proper operating range (only 1 running 30psi, and it did that for a good 6 months of comping before it exploded).
The oil running through a diesel is just as good, if not a better lubricant than what petrols require.

Ive often asked for other reasons or data showing why this is the case, and the only come back is that they cant be rebuilt.
Well so be it, they also last 10 times longer than any bush bearing unit, I consider this to be doing it the right way.

The only time material can enter the motor through a turbo failure, is if the compressor wheel disintegrates, weather it be ball bearing, or bush bearing if it does fail badly, both are just as likely to cause shaft movement which will destroy the comp wheel.

The fact that you have been told the ball bearings are able to enter the motor in the event of a failure astounds me. Who do these people think they are giving advice like that? I would run the other direction from who ever told you this nonsense as it is simply an impossibility for the bearings to even leave their completely separate turbo core and somehow end up inside the compressor cover.

Here is a graph posted up as promised. This vehicle had a hiflow turbo fitted (td05 unit dont know exactly what trim) . Couldnt find the afr/boost graph for them unfortunately.
Tons of smoke down low to try and get the turbo on before, zero smoke with the gt28.
Tuning was on the mild side of things, with afr being up in the 22:1 range at full throttle from memory

Image

Some of the tests we done on various 'custom' and off the shelf turbo's. None lived up to the promises of the manufacturer.
Image

Patrol that was in the shop today making a not so bad 400hp at 4 wheels. Ill let you guys guess the motor.
Image
Image
Image
Last edited by Northside 4x4 on Wed Apr 06, 2011 4:20 pm, edited 1 time in total.
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Re: td42 best turbo

Post by hulsty »

Duramax
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Re: td42 best turbo

Post by Northside 4x4 »

hulsty wrote:Duramax
+1 Rep for being quick and right :)
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Re: td42 best turbo

Post by uzdnabuzd »

well a quick update of where i am at with mine....No dyno graphs sorry. Dieselex should be able to give some fairly accurate data. it starts to boost at 1400, approx 30psi at 2000, 42psi not long after and will hold boost till 4500 (this is where we have the fuel ramping down) revs to 5300 with no noticable loss of power.
It has 4.11 diff gears and 37" tyres. egts are superb. wont go over 700 pre turbo....

This is obviously not suited to many needs...But gives people an idea of what you can do. Engine life is unknown and i am not really fussed. Only time will tell. I believe that everything has been done possible to give this motor the best chance of life! Race conditions are not engel round style, more so outback/cliffhanger style. Realistically i will be happy to get a couple of seasons out of it before its cactus.

Cheers
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Re: td42 best turbo

Post by Northside 4x4 »

700 is a scary number! You thought about maybe a water/meth injection setup on that?
Will drop that close to 100deg.
Anyway keep us posted, be good to get some info or dyno graph if ever possible.
If nothing else it will show us what a beating these things can cop anyway ;)
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Re: td42 best turbo

Post by UGOTNUFN »

Northside 4x4 wrote:700 is a scary number! You thought about maybe a water/meth injection setup on that?
Will drop that close to 100deg.
Anyway keep us posted, be good to get some info or dyno graph if ever possible.
If nothing else it will show us what a beating these things can cop anyway ;)
From this statement I assume that you don't do any steady state load ups to see how high egt's will actually go???

Are your pyro measurements only taken over the time taken to complete a dyno run???

A StD TD42 factory turbo gu will see 700 degrees easy all day everyday with ma and pa kettle towing their van around OZ for hundreds as thousands of K's!!!!!!

I mean people bandy around post turbo safe egt's of 600, that's more than 750 on any turbo combo!!!
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Re: td42 best turbo

Post by hulsty »

Northside 4x4 wrote:700 is a scary number! You thought about maybe a water/meth injection setup on that?
Will drop that close to 100deg.
Anyway keep us posted, be good to get some info or dyno graph if ever possible.
If nothing else it will show us what a beating these things can cop anyway ;)
IMO I think 700c pre turbo is quite conservative, especially on a factory turbo engine with piston oil cooling, pistons designed for a turbo application etc.

I read of heaps of people sticking to 550c POST turbo with the probes something like 100mm down the dump pipe or something silly like that, pre turbo those temps would be way higher than 700c, all on engines never designated to have a turbo fitted from the factory.
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Re: td42 best turbo

Post by Northside 4x4 »

I missed the pre turbo part. So used to people talking post turbo as has been said 100mm + down the dump pipe.
Most of the egt testing I do depending on the car is between 1min and 2mins at full throttle.
Very few engines would ever experience this in real life.
But, I also do pre/post pressure as well.

Wonder if anyone has ever done individual cylinder temps on a td42. might be the next thing I will look into.
Seems to me like 90+% of the rebuilds we do are cracked pistons in pot 1 & 6, Due to the natural flow restriction to these cylinders.
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Re: td42 best turbo

Post by uzdnabuzd »

I believe Matt McCiness(Laminova) has done this. They are getting a pressure and temperature variance across all cyclinders of less than 1psi/1 deg C. I run a custom 6 core that he built me. Post cooler temps are not exceeding 75degC which i am very happy about given the amount of boost that i am running. My intercooler radiator is a PWR GQ 50mm core rad with AU thermos on it so it has the ability to cool the water.
The biggest mistake IMO with W/A intercoolers are they do not have big enough radiators to sustain temps, nor do they have the air flow or water speed. I need to pump 16 gallons per min (actual flow not a figure on the side of a box) for my setup to work efficently. I can not remember the CFM air figure however i know that AU fans just flow enough.
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Re: td42 best turbo

Post by Northside 4x4 »

For sustained temps like you are putting out a big radiator and flow is a must I agree.
For most vehicles however, you can get away with a significantly smaller unit, without loosing any cooling capacity.

With the temp/pressure, I actually ment the exhaust manifold side of things.
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Re: td42 best turbo

Post by CustomTurbos »

You know, this vehicle gets me more than a bit excited.

I cant help myself but post slightly OT, I just had a light bulb moment that has undoubtedly solved the problem I had with interference in my vnt controller.....

For those who dont know, and that would be almost all of you, I designed and built a simple but programmable vnt controller that worked great on the bench but failed in real life. The reason was simply pwm switching noise interference causing havock with my rpm pickup circuit. Due to rush to getting the vehicle ready for racing, the project was put on ice and the work directed at finding a suitable wastegated turbo. It really wasnt a huge problem to get the thing finished/modded, but with no real requirement to do it......I didnt finish it :-)

It is worth pursuing though because we got 201hp @ wheels @ 2000rpm without smoke steady state which wasnt bad (277hp @ 3200rpm also no smoke and egt's were VERY low for the boost), but without being able to make it work properly dynamically, it was no good. We didnt test at any higher rpm because at those levels in steady state, we didnt want to blow anything up - seemed like big power at the time. I am very confident we can do 350hp @ wheels as the pump ramps up with rpm and is all go till much higher, plus considerabley more fuel is available on tap.

Anyway....... now I am all excited and cant wait to give it a go again.....
uzdnabuzd wrote:I believe Matt McCiness(Laminova) has done this. They are getting a pressure and temperature variance across all cyclinders of less than 1psi/1 deg C. I run a custom 6 core that he built me. Post cooler temps are not exceeding 75degC which i am very happy about given the amount of boost that i am running. My intercooler radiator is a PWR GQ 50mm core rad with AU thermos on it so it has the ability to cool the water.
The biggest mistake IMO with W/A intercoolers are they do not have big enough radiators to sustain temps, nor do they have the air flow or water speed. I need to pump 16 gallons per min (actual flow not a figure on the side of a box) for my setup to work efficently. I can not remember the CFM air figure however i know that AU fans just flow enough.
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Re: td42 best turbo

Post by Northside 4x4 »

VNT is great for custom jobs and big hp applications. But not much good to a bolt on community or the average tourer etc..
350hp, out of a td42?
Using shielded and earthed cabling will help with your interference problem, but I couldnt think what would give off enough interference to disturb a PWM solenoid or controller on a td42. Normally its a hipo ignition system that causes problems, but there is none on a diesel...
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Re: td42 best turbo

Post by CustomTurbos »

It was the switching noise from the collapsing field in the solenoid that interefered with the low level signal that came from the std TD42 rpm pickup. I will shield it and run an optical decoupler next time I play.

There will be a time not too far away, that VNT in the aftermarket will be the norm....

The purpose of the installation was simply to have the lowest egt's and widest power band. Its still a DIY enthusiast style application right now, not cookie cutter stuff.
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Re: td42 best turbo

Post by Northside 4x4 »

Possibly, but most of these cars are quite long in the tooth now. WIth alot less people willing to spend money on them, and even fewer company's still doing R&D on new products for them.
R&D for petrol VNT though, thats gonig to boom very soon.

I know what you mean about the solenoid. You could try a worm or stepper motor to control it without this problem.
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Re: td42 best turbo

Post by Dzltec »

Interesting read. I think the op has opened up a whole can of worms :) which he may not have known about. My thinking is if you have a power figure in mind and can put a combination together that works well, then that is the right turbo choice, however some peoples opinions will vary.

Diesellex, to make 350rwhp or are you talking fw hp, what fuel delvery in cc's per 1000 shots is required? 350rwhp is 260 odd rwkw, that needs a lot of cool air and a lot of fuel, as well as god engine internals and head gasket sealing to hold it all together, also revs come into play for this to happen.I don't think a single turbo would allow this on a td42 and keep good low down torque. I can be proven wrong though.

Keep up the discussion......its very healthy to show what can be done.


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Re: td42 best turbo

Post by Northside 4x4 »

The highest i have seen at the wheels is 276hp. That being Heath's truck and I think even that was a feat for a well used truck, not a dyno pony.
350hp.. I would say near impossible but if I see a dyno graph I will believe it.
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Re: td42 best turbo

Post by CustomTurbos »

Well, maybe I should have been more conservative and said 300-350.

This is at the wheels, anything else is an approximation, might have been on 31's because the 35's were too chunky IIRC. It was a fixed rpm run to test and tune the vnt:

2000: 151kw
2500: 177kw
3200: 207kw (this was supposed to be a 3000rpm run, but when I checked the exhaust pulse frequency in Hz during the vid using my FFT audio tool, I found it was 3200rpm)
3500: 217kw

The 207kw run was actually videoed to double check exhaust smoke. Unfortunately you get to hear verbally what the car did bit not see it on the screen. You can see how clean the exhaust was though.

So the most I have seen is 217kw @ tyres at 3500rpm, that was with the same VNT turbo, just on 40psi boost, thats a tad over 290hp and only on 140cc. Since there was no smoke and the VE pump can do 180cc and there is another 1000rpm higher to play with.......plus water injection is a possibility.

Now can the bottom end handle it? No idea....... I know Dieseltec did 177kw @ wheels @ 55psi and no intercooler with compounds and one of the rods didnt like it. DieselTec - Did you check to see if the piston on that cylinder picked up? Maybe there was a slight seisure. Anyway, peak cylinder pressures would have been enormous without an intercooler at that boost.

What was very interesting when playing with the vnt was the power vs boost. There was a definate undisputed sweet spot and it was more sensitive than I had imagined. With the experienced dyno operator advising the output, I closed up and opened up the vanes accordingly in "boost float" mode with aneroid boost disconnected. So with fixed fuel load, the power went down when too rich and down when too lean. Could easy drop 3kw not far off ideal in either direction. OK so it isnt that much, but significant enough to be very obvious. So exhaust A/R really affects overall efficiency and this is where the vnt shines through.

The hard part with VNT is the control strategy. By this I mean, do you run simply in max boost control mode with a fixed starting A/R or do you have a boost curve that is based on max load varied with rpm or do you do a 3D model and run boost vs rpm to maintain AFR or do you run of an AFM and forget about boost altogether (except for maybe a 45psi overboost cutoff) and maintain AFR independent of everything else (ie who cares about air temps, or boost, lets just maintain 17-18:1.....? In my opinion the latter isis the best option, but I have adopted a different strategy that effectively achieves 90% of the latter much easier and without an AFM. It is a Mark1 after all, good just to get something working well on a first pass....
LX470 1HDFTE
Performance Direct Bolt On Turbos for: 1HDT/1HDFT/1HDFTE/12HT/13BT/1VDFTV/1KDFTV
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