Boost and fuel increase on 4m40 with EGTs higher??

[zane]

I turned the turbo fuel diafram around to face the battery today (90degrees) and installed the boost tap in the 2.8t and here are my findings.

Egt much the same at 100 Ks sitting around 310 pre turbo.

Egt rises rapidly with foot to floor and hits 600 in about the time 100km is met. Much quicker than pre fuel and boost increase.

Waste gate trips at 1 bar. (14psi) and sounds awesome but not practical. Standard peak was .8 bar.
With boost controller wound hard anticlockwise would boost 1.35 bar without tripping waste gate.

Although higher EGTs on acceleration I don't seem to get lots of black smoke?

I could either space the waste gate or plug the outlet to waste gate and rely on the boost controller to get EGTs lower?? Is that right??

I don't want to boost over 1 bar for reliability.

Help appreciated.

[tgaguy1]

Until you remove or disable the boost pressure relief valve in the inlet manifold you will not be able to control your boost pressure properly.
The boost tap you have installed is just a controlled bleed off of boost sense pressure felt on the diaphragm of your waste gate. So opening it up more essentially lies to the waste gate and tells it is boosting less than it is. If you play around with spacers or permanently close off waste gate you are gaining nothing that the tap you have installed is not archiving.
Have a read of this link.
http://www2.pajeroclub.com.au/forum/showthread.php?t=35256&page=2
There are a lot more adjustments to play with on your fuel pump that will improve your performance safely.
Always adjust fuel to the modest side as the 4m40 head does not like heat.

[zane]

So is the blowoff sound I hear the wastegate or the inlet valve you mentioned?

When I first put boost tap this morning it was cranking right up to 1.4 bar but now I can move it wide open or shut with little difference. Always trips at 1 bar?

Definitely is going heaps better but in first 2 gears it always peaks out well befor gear change is needed making it no value.

Would spacing wastegate help?

[tgaguy1]

Yes that sound will be the pressure relief valve. Probably was a bit stuck until you blew I out with too many psi's. From memory it is set to release at 15 psi (1 bar) from factory. It is not adjustable.
Has nothing to do with the waste gate.
Relief valve looks like this
http://www.ebay.co.uk/itm/2-8-INLET-MANIFOLD-PRESURE-RELIEF-VALVE-MITSUBISHI-PAJERO-SHOGUN-/370764483460?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item5653490b84

And is located on your inlet manifold. can be removed and replaced with a blanking plug as it is a standard pipe thread

[zane]

Just realised my dumb mistake. I've attached boost controller wrong which means it's just the waste gate tripping. Will fix in the morning.

I'm still surprised I'm not getting black smoke though. Would be interesting to have an air/fuel gauge.

I've read the above thread a few times on pocuk and impressed with their detailing.

[slidenyo]

putting a bleed tap on your wastegate line will just hold it closed longer as it will open at the predetermined actuator pressure, effectively increasing top end boost.

rotating your diaphragm and fuel delivery pin to its most aggressive setting will increase the on boost fueling,
shimming the pin down will advance on boost fuel delivery,
altering the diaphragm's spring pretension will also effect the advance on delivery.

you're in the right frame of mind though you have an egt gauge,
tuning the Zexel ve pumps is pretty well published.
personally I'd look for those egts foot flat with a 2 tonne trailer on up the steepest hill you can find.
adjusting the fuel delivery screw to fuel a little more off boost and returning the diaphragm/boost aneroid to standard
may well work better, remembering an idle reduction will be necessary.

[coxsy]

is it a Ali head or steel both get soft at 600c

[zane]

It's an alloy head. I'm up to 600 degrees from 0km foot flat at 100 mark

Gets hot real fast. I'm not happy with fueling so need to redo the turbo fuelling as no smoke coming out and only boosting.8 bar.

All though I don't find it gets any hotter than 650 with foot flat.

350 at 100km

[SMOKEY]

I would be happy with those readings, my 1KZ with foot flat up to 100kph would be more like 700deg C, and once when not paying attention while towing hit 800. 350deg C at 100 looks good to me, remember a head wind or even very slight gradient will make a difference. In all the research I have done and it's hard to get any creditable stats your ok up to 720d C, for short periods , I try to keep mine under 650 with the odd spike over 700. Then again my son has a 185 Surf with the 1KZ and he drives it like he stole it even tows a big heavy 20ft caravan, he must be hitting 800deg plus and it's getting close to 300,000k's original head and motor not touched. I'd be sitting on the side of the road with all the coolant on the ground and steam pouring out.

KEEP AN EYE OR TWO ON THE GAUGE,

FITZY.

[zane]

A few weeks after the EGT install I noticed irregular readings and indicator/lights interference. I thought it was an earth issue, however just realised it was a faulty pyrometer probe. Just replaced it and we are good again..

I'm happy with my readings.

Seems the heat melted the two wires together coming out of the probe causing a positive wire issue????

Anyone experienced that?

[Pajmad]

im running 25psi in my challenger with 357000 on the clock all I did was raise the base diesel screw and pushed the pump all the way towards the head, don't even use the waste gate actuator its un hooked. shes been like that since 280000 and I tow regularly. my temp guage doesn't even rise towing a safari on a trailer up the spooners range, using the fueling to regulate boost pressure ensures egts don't get out of control as the fuel is burnt properly proportionatly to the boost.