[LZ_Pan]

yeah alright mates, i am looking for a power increase and since i dont use it as a dd i dont have any inhibitions of it going bang sooner or later. do you have the ct26 kits available for sale yet? i want to go ahead and give it a go.

[Hulsty]

Originally Posted by Tim-HJ61

• The speed the turbo spins up is remarkable. Clearly faster than the standard CT26, this version whips around to max boost of 18psi really quickly, the boost compensating aneroid opens up the IP rack and dumps a heap more fuel. There is no more smoke because of the high air flow providing enough flow to burn all the extra fuel. Suddenly the end of the road comes up much quicker than expected.
• the ONLY change I made was to instal this turbo. No fuel supply mods were made as part of this install, that was previous. Boost WAS lifted by 3 psi to ensure the boost compensating aneroid opened correctly and didn't create a resonance.

Tim/Graeme are you able to expand on the aneroid and how it works and the resonance ?

Is the aneroid what toyota refer to in their manual (13BT) as a "guide bushing" ?

[alsworld]

Ok, how do i get one of these bolt on turbo upgrades by Graeme?

[Ducks]

Originally Posted by alsworld

Ok, how do i get one of these bolt on turbo upgrades by Graeme?

Send him a PM. You can either send him your turbo and he modifies it and sends it back to you or maybe if he has a core, he can modify one he has and you just send him your turbo as a core.

Chad

[Tapage]

which are the mods .. ?

[gbentink]

Resonance:

This doesnt happen with the std CT26 because it is much slower in response (yes I hear you say "sales BS" but its simply true).

The std fuel pump when adjusted belts in extra fuel from 14-17psi. If the boost is set to 17psi, the turbine speed drops quickly and so does the boost. The aneroid is very quick to respond and drops fuel. The wastegate then closes but the turbine doesnt have as much energy available from exhaust because of the reduced fuel from the aneroid and must build up again. It was ~ 2Hz resonance.

meeting with Tims reluctance, I asked him to gradually increase boost until the problem dissappeared on the basis that so long as the aneroid was fully depressed, the fuel wouldnt reduce during the opening wastegate and the exhaust energy would be available. It worked perfectly fine.

The other way to achieve the same result is to wind the max fuel screw in a bit. This lowers the fuel but also lowers the boost pressure required to max out the new setting.

there are a few other solutions too - such as playing with a few different additions of volume between the boost source and the aneroid, adding in a restriction to reduce the rate of aneroid fluctuation or change the wastegate boost controller from a ball and spring arrangement (where the wastegate see's nothing then is suddenly hit with boost) to the old style bleed (restriction in line from boost source followed by what is effectively a leak; the size of which you vary to meet your boost requirement). Adding a front mount IC might also help because of the large volume causing a less rapid pressure change.

I liked the higher boost option because it optimises response, guarrantee's full fuel and lowers your EGT's. Plus, it was a turn on the boost screw away from being fixed!

On a stock pump with max fuel adjustment maxed out, 17-18psi would probably make more power to the wheels (say an extra few HP) than 21psi, however at 21psi, because the turbo is operating efficiently your EGT's will be lower, exhaust gas cleaner etc. This is solely on the basis that your fuel pump spring is set to max out at 17psi. that is what was measured by a local injection company on my Mates 4.76L 12HT when he had his pump checked.

I would be VERY interested to see the dyno figures of a 12HT that has the exhaust mod, this turbo and 21psi but no intercooler compared to changing nothing but adding an intercooler.

[Tim-HJ61]

Hulsty

The aneroid is at the rear of the 12h-t injection pump. When boost pressure is applied, it pushes a diaphragm which is attached to the fuel control rack and opens it up more and provide more fuel.

It is designed to add more fuel to take advantage of the extra air available from the turbo at high boost. This is a standard feature.

Normal factory set boost is 7psi on a 12h-t. But the aneroid opens fully at the specs Graeme has stated Around 17psi. What we are doing is unleashing the potential already built into these engines and injection pumps.

After a week of regular city suburb and freeway driving, I am remaining very thrilled with the response from the new turbo. The ultimate test was today when my wife had a ride. She could certainly tell the power was increased and the turbo whistle was not an annoyance for her despite sitting close behind it. (RHD model)

What I'm really liking is that the engine stays in the full boost range when changing gears, even up regular hills, so acceleration is not slowed by lost revs and boost.

I've not yet modded the lower support bracket and personally I believe this is important to reinstall to add security to the install and reduce strain on the manifold. When our weather cools down a bit, this is my first shed job.

Tim

[gbentink]

Originally Posted by Tapage

which are the mods .. ?

The mods are many.

I think Marilu could do with the change :-)

[gbentink]

Hi, well Tim and I will be heading over to get the HJ61 with the new turbo dynoed on tuesday 22nd Feb. We will also video it and take some in car video of gauges. Tim was unsure what boost he was running because his gauge only went to 15psi and the gauge was roof consol mounted so you couldnt see the tacho and boost at the same time. Now he has a 22psi gauge resting near the tacho so you should all see exactly what it does against the rpm.

One run on Vege Oil, one run on Bio Diesel. So, I dont expect to quite get the 160-170hp@ wheels that you would from straight Diesel, but should get within 10-15%. Lets see if the theory matches the practice! They do 90hp at wheels std.

[Tapage]

Originally Posted by gbentink

I think Marilu could do with the change :-)

sure she will .. but I would like to know what makes the upgrade that good ..

[dousty]

Originally Posted by gbentink

Hi, well Tim and I will be heading over to get the HJ61 with the new turbo dynoed on tuesday 22nd Feb. We will also video it and take some in car video of gauges. Tim was unsure what boost he was running because his gauge only went to 15psi and the gauge was roof consol mounted so you couldnt see the tacho and boost at the same time. Now he has a 22psi gauge resting near the tacho so you should all see exactly what it does against the rpm.

One run on Vege Oil, one run on Bio Diesel. So, I dont expect to quite get the 160-170hp@ wheels that you would from straight Diesel, but should get within 10-15%. Lets see if the theory matches the practice! They do 90hp at wheels std.

Awesome, I look forward to the results and video. Thanks

[dousty]

Dyno today!! Goodluck!

[Tim-HJ61]

Dyno done chaps.

GB has the results. Lots of numbers that didn't really make a lot of sense to me.

The guy running the Dyno is the expert performance engine builder who's been involved in race engines, petrol and diesel for years. He had a smile on his face and said the results were very good. So did GB, but he often has around engines.

The things that impressed me as the owner were the nil smoke under full power, both on 100% diesel and on 100% veggie oil. They normally do a few runs to show the power and torque figures, with the machine calculating the drive line frictional losses as it is running down to idle again. This way they can get a reasonably accurate figure for at the wheels and another for at the engine.

All these graphs are very nice to look at and are really the only 'scientific' comparison we can have. But they don't necessarily indicate the important driveability advances from mods.

Due to the nature of the mods we have done, the dyno guy was interested in seeing how much load he could put on the engine at full throttle in 4th gear and see what the revs were at when the turbo started to lose boost.

GB will post the results, but even at this high low test, the smoke was negligible and very impressive. Also impressive was how the engine kept the EGT;s low. As I noted during normal driving, this is at least 100°C lower than with the old turbo. Even during this full power, full boost test at 2000 rpm and lower, the EGT did not rise above 600°C, when I would have expected them to be going north of 700°C at least.

It is so much easier to see results on the dyno than trying to drive at the same time, and more accurate assessments can be made.

Before GB posts the results, let me remind you this engine has done 230,000km, at least 80,000km on 100% veggie oil with a two tank system. The only modifications apart from the new turbo supplied by GB are a 3" exhaust system, and I have unwound the fuel screw to supply maximum fuel, and boost is set at about 1.4bar - 21psi. Apart from that, this is a standard untouched engine that I drive around each day.

GB has some video to process, which I imagine he is playing with now.

Oh, the other thing was that it was a hot day here today. We ran the dyno late afternoon and the ambient temperature was around 35°C. The cross over pipe reached 100°C on the outside during the high power runs, so what the charge air temps were are anyones guess - probably 150°C. An intercooler would really help!!

Tim

[gbentink]

***EDIT NOTE***

I should point out that the boost being run here is more than is required to make the power it is making (1.2Bar should do it without an intercooler and would probably make a few more KW as well due to reduced pumping losses). However because the pump hasnt had some internal adjustments to the way the aneroid behaves, the boost being run makes it work as well as it can on stock settings. As an additional advantage to your fellow man, the exhaust is very clean under acceleration wheras most improvements to old school diesels make more smoke.

The boost lowering with rpm increase was fixed by increasing the tension on the wastegate actuator. The std 5-5-7psi wastegate didnt have enough clamping force. As it is now, it holds 21psi to 4000rpm.

***END OF EDIT***


I will hopefully post the video link on yioutube tonight. You can see the tach and boost gauge no problem and even get a look at the dyno hand controller at a few points to see what it is actually doing at the wheels.

Some interesting figures for you:

CLEAN EXHAUST AT ALL LOADED RUNS!

- 1600rpm 1.2 Bar 65rwkw (~440nm at crank)
- 1800rpm 1.45 Bar 75rwkw (~450nm at crank)
- 2000rpm 1.45 Bar 83rwkw (~450nm at crank).
- 3000rpm 1.3 Bar 97rwkw (***EDIT*** now holds 1.5Bar boost to 4000rpm )

- 3400rpm 1.25 Bar ~100rwkw off dyno sheet. (***EDIT*** now holds 1.5Bar boost to 4000rpm)



Temperature was 35-36 deg C. Car had been dynoed immediately after driving in peak traffic for over 40mins, no intercooler. Intake crossover was measured at 105 deg C and rising. Never went over 600deg C on Diesel (did go to 660deg C on vege oil probably due to delayed combsution - needs to have timing advanced a bit). Engine untouched original and std they do 67kw at wheels.

Bear in mind the fuel pump is internally std, so external adjustments have only been performed.
All videoed. Will be YouTube loaded soon.

Clean exhaust at full torque and around 600 degrees EGT pre turbo.

Vege Oil

- 2200rpm 81rwkw 1.5 Bar, 660deg C
- 3400rpm 92rwkw 1.25 Bar 650deg C

[Dougal]

Subscribing.

[dousty]

That is an awesome result, well done. I am certainly keen to hear more about these mods.

[gbentink]

Only need to add a bit more spring pressure on the wastegate and should hold boost flat to 3400rpm no problem at all. Just in case anyone was wondering.....

[Tim-HJ61]

Waste gate shimmed out tonight and as predicted, it has added the needed pressure to the spring inside the waste gate. Standard is quite soft and opens too easily. Shimming out the actuator adds pressure to the spring so it opens and closes with more vigour.

I'll try to remember to add a picture of where to shim out the unit.

Tim

[gbentink]

Low rpm dyno run at full load:

http://www.youtube.com/watch?v=eDk76koZXZE

I would like to see anyone do that with a std CT26 with only 75cc of fuel.......

[Tapage]

I can't see the complete vid ..