80 series Boost compensator (2 Viewers)

[Jim_Phillips]

I have been reading on the Lcool site about improving performance by adjusting the boost compensator:

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According to the write up, the boost compensator is the diaphragm that sits on top of the fuel pump. Has anyone done this job. If so, can you describe what the boost compensator looks like so that I can be sure I am looking at the right thing. A photo would be great! Thanks for any ideas. Cheers, Jim

 

[Falco80]

Hi Jim, this mod is easy to do. I did mine a couple of months back. The boost compensator diaphragm is on top of the injection pump with a screw and locknut on top in the middle. I don't have any pics as i'm at work, but if you read the instructions and know what you are looking at it is very straightforward. I only did the "Boost compensator characteristic tendency" and the "Maximum off boost injection volume" tweaks. I might do the "Boost Compensator Profile" one day but for now the motor runs great and these tweaks made a noticeable improvement.
Ya gotta love mechanical injection!

 

[Jim_Phillips]

From the way you describe it, it should be obvious.. but I'm afraid that to me it still isn't. Is there anyone who knows what I am looking for that can copy my pic, add an arrow using paint and repost? That would solve all my problems! Cheers,

 

[Tapage]

second pic .. yellow painting on top .. it's your boost compensator screw ..

 

[Falco80]

Damn Jim, your setup is a lot different to mine. Your pump has a lot more plugs and hoses hanging around it. It's going to be a bit more tricky to adjust i think, unless you have midget hands!
Tapage is correct, the screw with the yellow paint is on the top of your boost compensator.

Check this out....

 

[Jim_Phillips]

Dan. That's a nice clean engine you have there. I can see it will be a little tricky for me with my sausage size fingers to get this done right. Thanks for labelling the pictures - that shows it perfectly.

To quote the write up on LCOOL - 'On the rear face (towards the rear of the car), just under the diaphragm is a 12 mm bolt with a rubber drain cover/tube covering it (Aussie spec only. The European models have that BACS tube in there). Pull the rubber cover off and undo the bolt. Depending on which tools you use, you may have to remove the fuel inlet pipe first. It's tight in there....'

What is a BACS tube?

I can clearly see where the off boost injection screw is. I assume the compensator tendency adjustment will be at the back of the pump as per the lcool description. It is going to be tricky to get to it - even if I remove the fuel inlet pipe as I can't even see the bolt as it is.

It would be great to hear from someone who has the same IP as me and hear from them how they managed. Cheers, Jim

 

[Falco80]

Jim, i'm not sure what the BACS tube is myself. On mine it was just a rubber cover covering the bolt head, which is located just under the lip of the diagphragm housing facing the rear of the engine bay. I couldn't actually see mine either so i used a small rectangular inspection mirror. That made it a lot easier to see what i was dealing with.

I suggest setting up a decent light and using a small mirror to have a look in there. Once you can actually see the rubber cover/BACS tube it will all make sense. Good luck!

 

[70sguy]

Cool stuff.. Will be doing the boost compensator mod to my -FT as soon as I get it up and running in my 97 FZJ and get a few miles on it as a baseline for stock performance.

I will be getting a crash coarse on BACS SICS etc pretty quick.

 

[Christian]

I for one would like to know how the BACS system works, reason being that I have just put a 1KZ-T in an old Volvo 6x6, and it has the BACS vakuum line on it. The line goes up to what appears to be a valve (a black plastic thingy with a wire connection on it) and then attaches to the general vakuum system.
Anybody got any info on it?


Disregard the above, I just found out that what I thought might be a BACS is probably a PCS 8Power control system) and I have found that if no vakuum is applied it limits the power of the engine...

Thanks anyways!

 

[landcrusher80]

I wonder if the same mod can be applied to a 1HD-T?

LandCrusher80

 

[Workhorse]

The same applies to the HDT.

The HDT did show more signs of life at lower(as well as in the highest) RPM's after tweaking it with the information provided by LCOOL. Great information, works nicely.

I look forward to tweaking my HDFT soon as well.


Ross

 

[VTCruiser]

great link! I was wondering if there was a way to get more low-end response. i'll have to try this on the 1HZ-T when I get home. Thanks!

 

[Dutchie]

great link! I was wondering if there was a way to get more low-end response. i'll have to try this on the 1HZ-T when I get home. Thanks!

Up the off-boost fuelling a bit

 

[Jurgen van den Brink]

From the way you describe it, it should be obvious.. but I'm afraid that to me it still isn't. Is there anyone who knows what I am looking for that can copy my pic, add an arrow using paint and repost? That would solve all my problems! Cheers,

Since these electric connectors are on the boost compensator, can they be used to measure the boost level?

 

[Jurgen van den Brink]

Since these electric connectors are on the boost compensator, can they be used to measure the boost level?

Mmh, I guess my mail was not that specific... What I'm trying to figure out if I could use those connections / wiring to connect a boost gauge on the dashboard. But maybe it is a very silly idea of a rookie...

 

[70sguy]

None of those electrical connectors have anything to do with reading boost.
Boost gauges are generally a mechanical device. 1/8 NPT fitting into xover tube, or T into the wastegate feed hose. Hard plastic tube from boost source right to the back of gauge. Only electrical requirement is for the light. There are some fancy electronic Boost/Pyro/oil pressure gauge set ups.. Madman etc.

 

[sandcruiser]

Can someone tell me more about how the PCS works?
I think that my IP has it, and that it is not connected... I've got some electrical wiring that goes to nowhere... I think it is the PCS.

Would love to know more about it, but the FSM doesn't offer much information.