13B-T Actuator Disconnected + standard fuel = bang?

Slideways · **Posted:** Sun Jul 17, 2011 7:21 pm

I have a BJ73 70 series Landcrusier with 13b-t fitted, I then made a 3" exhaust including turbo downpipe. It went a bit better and seemed to spool quicker.

I don't have an EGT (I know, playing with fire!)
No intercooler yet.
Standard fueling and no noticable black smoke.

I fitted a boost gauge and get a solid 8psi.

Next I was going to adjust the fueling and modify the actuator rod to be adjustable, but then I read that you can remove the hose from the actuator and it will only run as much boost as it can versus the fuel available (unlike petrol turbo which will run lean and melt pistons if no actuator to limit boost).

So I tested it by pulling off the hose and blocking it off temporarily. Now the boost fly's up to 14psi+ sometimes 18psi.

I didn't do this for long because I wasn't sure how safe it really is.

Can anyone answer the following?

- I assumed by the theory that boost on a diesel is determined by the fuel available and that my standard fueling would mean it wouldn't make much more boost that with the actuator, but it doubled the boost level?
- Is it safe to run with actuator blocked off on a 13b-t (with the standard boost compensator)?
- Will the 13b-t boost compensator keep adding more and more fuel or is it limited by the 'max fuel' screw?
- Do I need to add more fuel?
- Should I adjust fuel via the boost compensator or the max fuel screw?

Cheers

crazyclark31 · **Posted:** Sun Jul 17, 2011 7:49 pm

Slideways wrote:

I have a BJ73 70 series Landcrusier with 13b-t fitted, I then made a 3" exhaust including turbo downpipe. It went a bit better and seemed to spool quicker.

I don't have an EGT (I know, playing with fire!)
No intercooler yet.
Standard fueling and no noticable black smoke.

I fitted a boost gauge and get a solid 8psi.

Next I was going to adjust the fueling and modify the actuator rod to be adjustable, but then I read that you can remove the hose from the actuator and it will only run as much boost as it can versus the fuel available (unlike petrol turbo which will run lean and melt pistons if no actuator to limit boost).

So I tested it by pulling off the hose and blocking it off temporarily. Now the boost fly's up to 14psi+ sometimes 18psi.

I didn't do this for long because I wasn't sure how safe it really is.

Can anyone answer the following?

- I assumed by the theory that boost on a diesel is determined by the fuel available and that my standard fueling would mean it wouldn't make much more boost that with the actuator, but it doubled the boost level? Yep this will happen. You'd be quite safe to leave actuator disconnected and leave fuel as it is. to a piont as long as you've got no smoke your egts should be okay
- Is it safe to run with actuator blocked off on a 13b-t (with the standard boost compensator)?Yep. The boost compensator actually limits rhe off boost fuel not the on boost.
- Will the 13b-t boost compensator keep adding more and more fuel or is it limited by the 'max fuel' screw? They fuel delivery is set by the max fuel screw
- Do I need to add more fuel? Would seriously look at getting an egt gauge before doing this to much. The standard turbo on these (ct26) is really only good for 15psi before the intake temps start to get really high. Would seriously look at getting a intercooler to
- Should I adjust fuel via the boost compensator or the max fuel screw? If your going to adjust the fuel do it with the max fuel screw.

Cheers

Slideways · **Posted:** Sun Jul 17, 2011 8:20 pm

Thanks for the reply.

OK so I'll just leave the fueling as is because it appears to be able to deliver enough fuel for almost 18psi.

I'm surprised about the boost compensator, I thought it added fuel on boost rather than limiting it off boost?

I'll definitely be adding an intercooler, I have one already but it would need to have the radiator spaced back and the shroud shortened so I'm looking at options to leave the radiator as is. Hardest part is where to run the intercooler piping without cuting big holes (which wof's are cutting down on, pun not intended).

tweake · **Posted:** Mon Jul 18, 2011 12:58 am

boost compensator limits off boost fuel.
however some have a overboost ramp and limit fuel when boost goes to high. i don't know if the 13b-t has that or not.

i would hook the wastegate back up and use a boost controller. turbo's can go inefficient at high boost and get less power as a result. not to mention excess heat can cause problems as well.

crazyclark31 · **Posted:** Mon Jul 18, 2011 1:04 am

i would hook the wastegate back up and use a boost controller. turbo's can go inefficient at high boost and get less power as a result. not to mention excess heat can cause problems as well.[/quote]
Have to agree with that. Using a boost tap give far better control over boost levels. I wouldn't be going any higher than 15psi with the ct26. Have found no real gain going higher than that. Also be carefull as they have a ceramic exhuast turbine(think its your model truck that has it(?))

Slideways · **Posted:** Tue Jul 19, 2011 5:09 pm

I have a boost tap but I don't like the idea of water being sucked into it in a river crossing.

Plus I tested it with a small leak and it ran LESS boost so it must be leaking too much air.

Being an air leak I'd think that it would slow down the spool as well as make the turbo work harder to maintain maximum boost.

I prefer the idea of modifying the actuator rod with a threaded section so I can shorten it but I'm not sure if I could shorten it enough to reach 15psi. I guess there is only one way to find out!

crazyclark31 · **Posted:** Wed Jul 20, 2011 2:28 am

on my tdo5h i've got it set so the gate only opens a little bit(maybe 5mm). Had to cut 10mm outa rod and thread it 10mm to get enough adjustment to go to 15psi.

jakwoo39 · **Posted:** Wed Jul 20, 2011 3:56 am

i run a boost controller on my 13b-t and have it set on 12psi, runs great and no smoke. when i had mine free boosting it went well over 20psi but didn't get much of a power gain
more air means the head will run cooler
and more fuel = more power not air

sibainmud · **Posted:** Wed Jul 20, 2011 6:24 am

Slideways wrote:

I have a boost tap but I don't like the idea of water being sucked into it in a river crossing.

Plus I tested it with a small leak and it ran LESS boost so it must be leaking too much air.

Being an air leak I'd think that it would slow down the spool as well as make the turbo work harder to maintain maximum boost.

I prefer the idea of modifying the actuator rod with a threaded section so I can shorten it but I'm not sure if I could shorten it enough to reach 15psi. I guess there is only one way to find out!

Water being sucked in?!? Diesel turbos never have vacuum in the manifold (fit a petrol boost gauge with inches of mercury {vacuum} as I have), never seen it below zero. That's why we have engine driven vacuum pumps for brake booster.

Big dump pipe over-comes slow spool up (not an issue).

Spacing the actuator housing works too, but by altering the rod length, you are pulling the diaphragm against the return spring, which IMHO is bit more stressful to the actuator.

Just my 10c.

Most the marine engines I work on have no waste gate or means of controlling boost and are used at red-line for hours on end.

Pays not to over 15psi without inter-cooler, and it can be detrimental to the longevity of the turbo.

Cheers,

Slideways · **Posted:** Wed Jul 20, 2011 4:04 pm

sibainmud wrote:

Slideways wrote:

I have a boost tap but I don't like the idea of water being sucked into it in a river crossing.

Plus I tested it with a small leak and it ran LESS boost so it must be leaking too much air.

Being an air leak I'd think that it would slow down the spool as well as make the turbo work harder to maintain maximum boost.

I prefer the idea of modifying the actuator rod with a threaded section so I can shorten it but I'm not sure if I could shorten it enough to reach 15psi. I guess there is only one way to find out!

Water being sucked in?!? Diesel turbos never have vacuum in the manifold (fit a petrol boost gauge with inches of mercury {vacuum} as I have), never seen it below zero. That's why we have engine driven vacuum pumps for brake booster.

Big dump pipe over-comes slow spool up (not an issue).

Spacing the actuator housing works too, but by altering the rod length, you are pulling the diaphragm against the return spring, which IMHO is bit more stressful to the actuator.

Just my 10c.

Most the marine engines I work on have no waste gate or means of controlling boost and are used at red-line for hours on end.

Pays not to over 15psi without inter-cooler, and it can be detrimental to the longevity of the turbo.

Cheers,

Lol good point about the water being sucked in, but I'm still a bit worried about there being an opening for water or mud to get in.

I'll look at spacing the actuator with some washers and see how that goes. If not enough I'll cut and thread the rod.

I do find that the spool is slower than I expected, reading on the IH8MUD forums there is a guy providing modified CT26's which spool much quicker. Claims 21psi by 2000rpm but I would have though this would mean a much smaller exhaust wheel so would limit boost up around 3000 to 3500 rpm.

Mine doesn't make 16psi until maybe 2700 or so. Could be a lazy worn actuator letting too much air through the waste gate I guess.

crazyclark31 · **Posted:** Thu Jul 21, 2011 2:06 am

our 3b 60 series has a ct26 on it and does sorta the same 7psi at 2400rpm. Get some in the know to have a look at your boost comp as it prob could do with an adjustment to help spool time.
Getting the ct26 modded could end up being a big cost/small gain exercise. If after more boost/better power might be better to look at a different turbo.

jakwoo39 · **Posted:** Sat Jul 23, 2011 3:10 am

Slideways wrote:

I have a boost tap but I don't like the idea of water being sucked into it in a river crossing.

Plus I tested it with a small leak and it ran LESS boost so it must be leaking too much air.

Being an air leak I'd think that it would slow down the spool as well as make the turbo work harder to maintain maximum boost.

I prefer the idea of modifying the actuator rod with a threaded section so I can shorten it but I'm not sure if I could shorten it enough to reach 15psi. I guess there is only one way to find out!

take the hose from the boost controller that the instructions tell you to vent to engine bay and connect it to your airbox.
this way unless you get water in snorkel you will never suck water in.
i have done it on mine and the vacuum in the airbox doesnt affect the controller at all

Hulsty · **Joined:** Tue Apr 13, 2010 8:26 pm **Posts:** 4

Slideways wrote:

Lol good point about the water being sucked in, but I'm still a bit worried about there being an opening for water or mud to get in.

I'll look at spacing the actuator with some washers and see how that goes. If not enough I'll cut and thread the rod.

I do find that the spool is slower than I expected, reading on the IH8MUD forums there is a guy providing modified CT26's which spool much quicker. Claims 21psi by 2000rpm but I would have though this would mean a much smaller exhaust wheel so would limit boost up around 3000 to 3500 rpm.

Mine doesn't make 16psi until maybe 2700 or so. Could be a lazy worn actuator letting too much air through the waste gate I guess.

I'm the guy from iH8mud with one of the modified CT26's. If you want more spool up you need fuel and a free flowing exhaust, I had my stock CT26 running 21psi, they dont have ceramic wheels.

Have now upgraded to modified CT26 and its significantly better than the stocker, I have been able to max out the fuel pump and keep EGT's well under control now at 20psi, though I have had it up to 30psi. Can hold the boost all the way to the governer, remember the CT26 is designed for much larger motors than a 13BT.

The wheels arent smaller, if they were boost would be worse as the clearance to the housing would increase. New turbo has much better designed wheels than the original unit.

crazyclark31 wrote:

our 3b 60 series has a ct26 on it and does sorta the same 7psi at 2400rpm. Get some in the know to have a look at your boost comp as it prob could do with an adjustment to help spool time.
Getting the ct26 modded could end up being a big cost/small gain exercise. If after more boost/better power might be better to look at a different turbo.

The modded CT26 is a low cost big gain exercise, less than $1K AU for a bolt on new turbo. Swapping to a different turbo will quickly add up to more than that

Slideways · **Posted:** Sun Aug 28, 2011 4:56 pm

Hey Hulsty,

Cheers for the info. Where did you get the turbo, is it from the States? I think my CT26 is getting a bit tired so could be an option in near future.

Hulsty · **Joined:** Tue Apr 13, 2010 8:26 pm **Posts:** 4

From Graeme, he is based in Peth, WA, Australia.

http://forum.ih8mud.com/diesel-tech-24-volts-systems/458353-toyota-ct26-upgrade-13bt-12ht-1hdt-1hdft.html

13B-T Actuator Disconnected + standard fuel = bang?

13B-T Actuator Disconnected + standard fuel = bang?

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