More power from GQ 2.8

[vbowste1]

Hi all
does anyone have any ideas on how to get a little more power and maybe some better economy out of my 2.8 turbo GQ without spending large amounts of money. would a front mount intercooler help much?
Im currently getting 15 litres to the hundred and not much power.

Also it gets hot when i use the air con and i have to turn it of till the temp comes down then i use it for a little and the temp comes up again......any ideas ? can i fit a bigger radiator ?

Any ideas would be appreciated.

Thanks

[Bigrig]

Hi all
does anyone have any ideas on how to get a little more power and maybe some better economy out of my 2.8 turbo GQ without spending large amounts of money. would a front mount intercooler help much?
Im currently getting 15 litres to the hundred and not much power.

Also it gets hot when i use the air con and i have to turn it of till the temp comes down then i use it for a little and the temp comes up again......any ideas ? can i fit a bigger radiator ?

Any ideas would be appreciated.

Thanks

Hey mate - when was the last time your cooling system was flushed by a specialist (proper high pressure flush of radiator and engine cooling system)? Also, you could fit a cold thermostat which opens around 12 degrees cooler than a standard one. I'd be trying these before lashing out on a new radiator.

What I've learned through my recent turbo inter cooling experience, is they LOVE cooler air - very generally speaking, every two to three degrees off the intake temperature equates to about 1 horsepower increase - mine dropped about 30-40 degrees straight off the bat when intercooler was installed (15-20 horsies). Definitely a plus, won't turn it into a speed machine, but should definitely make a difference.

Good luck with it all round mate.

[Vl-nitron]

hey mate a 3 nich exhaust will free it up a bit and give ya better fuel economy aswell

[YNOT]

A cheap way to increase power on the 2.8 is to block the EGR. As the others have already said intercooling and big exhaust also help. After that you start looling at engine tuning.
With the overheating I would start with a professional radiator flush, check all belts and hoses and check the fan hub operation. Iwould also be replacing the thermostat but with a standard part. If the cooling system is functioning correctly on a near standard engine there should be no need for a colder thermostat.

Tony

[97_gq_lwb]

When i had a 2.8 i played with the fuel pump and boost on the gq it is mechanical and their is basically 3 adjustments to balance on the pump.
First thing would be to fit an egt sensor then.
This will give you a bit of an idea on how it is done http://www.fourwd.org.uk/bosch_ve.html

[Bigrig]

A cheap way to increase power on the 2.8 is to block the EGR. As the others have already said intercooling and big exhaust also help. After that you start looling at engine tuning.
With the overheating I would start with a professional radiator flush, check all belts and hoses and check the fan hub operation. Iwould also be replacing the thermostat but with a standard part. If the cooling system is functioning correctly on a near standard engine there should be no need for a colder thermostat.

Tony

On the colder thermostat part - yep, true if it's running properly you shouldn't need a colder thermostat, however if you have it running properly (like mine) but have heaps in the way of the radiator (like mine), such as spotties, intercooler, air con radiator, oil cooler etc, then air won't be getting in as effectively and efficiently and as such, you may not be cooling properly and think its mechanical/cooling system related when it is simply airflow restriction - like me, most people don't remove the obstacles listed above, and simply fit a colder thermostat ...

How'd I go Tony? Did I pass the test??!! lol

[vbowste1]

Thanks for the info i will try some of these options or i may even buy a Toyota ( just jokes ).
About the radiator, i had a 91 patrol in the 3 ltr petrol and had to replace the radiator in that just because of corrosion and it was a big all metal one, cost me $750 and thats ok i thought. I am not a big fan of these new plastic ones as i dont want to be in the middle of a desert and have it fail from the heat.
And your right about all the things in front of the radiator.
Has anyone fitted a front mount intercooler to a 2.8 GQ before id love some help on how to do it, and what type to buy, as well as how big?
Thanks you all.

[Robo]

Agree with Tony on the thermostat being kept standard. for normal daily driving.
If your not careful lower engine temps can lead to richer mixtures.
Maybe not once engine warms in summer.
As computer and engine control is factory set and you properly cant adjust to suit new thermostat.
If you run cold thermostat in winter, bet enrichment is on the cards,even more so if you get wet, rain or creek crossing.
In winter you properly have interior heater going also adding to cooling the engine.
A rich mixture will cause engine to heat up and shorten engine life.
Not saying this is going to happen 100% for sure, But have seen these affects before especially in winter, Rich exhaust.
doing things like cleaning air-con condenser and radiator externally, for optimum air flow.
use de-mineralised water this raises boiling point of water to well over 100 deg mixed with proper coolant, not to mention less corrosion.
a proper designed catch can attached to water bleed screw can separate cavation/ bubbles from coolant, and slightly add to coolant volume.
A thermostat controlled oil cooler is another idea, also adds to volume.
larger air-con elec fan
Do you really need/use those spotties.
many things can be done to aid cooling.
Cheers

[97_gq_lwb]

I would be checking the fan clutch for the temp issues.
Also some gq's had a thermo on the air condensor that turned on with the aircon and some didn't but if it hasn't it couldn't hurt to fit one.
Personally for the intercooler i would go with a water to air rather then run a front mount with all the extra piping etc unless your upgrading the turbo as well i reckon it will just create more turbo lag and a 2.8 suffers bad enough now.

[Bigrig]

Agree with Tony on the thermostat being kept standard. for normal daily driving.
If your not careful lower engine temps can lead to richer mixtures.
Maybe not once engine warms in summer.
As computer and engine control is factory set and you properly cant adjust to suit new thermostat.
If you run cold thermostat in winter, bet enrichment is on the cards,even more so if you get wet, rain or creek crossing.
In winter you properly have interior heater going also adding to cooling the engine.
A rich mixture will cause engine to heat up and shorten engine life.
Not saying this is going to happen 100% for sure, But have seen these affects before especially in winter, Rich exhaust.
doing things like cleaning air-con condenser and radiator externally, for optimum air flow.
use de-mineralised water this raises boiling point of water to well over 100 deg mixed with proper coolant, not to mention less corrosion.
a proper designed catch can attached to water bleed screw can separate cavation/ bubbles from coolant, and slightly add to coolant volume.
A thermostat controlled oil cooler is another idea, also adds to volume.
larger air-con elec fan
Do you really need/use those spotties.
many things can be done to aid cooling.pertinence
Cheers

Yep, I hear you boss and don't contest most of it - never had a problem with low temp enrichment, and certainly the pros of a cold thermostat outway the "potential" cons (I say potential as only some experience it in very specific circumstances) by a long shot.

That said, that's the beauty of this place - so many ideas, so many opinions, but it's all for the good of making sure all options are on the table when trying to help out.

Top post Robo - all good stuff mate.

[YNOT]

On the colder thermostat part - yep, true if it's running properly you shouldn't need a colder thermostat, however if you have it running properly (like mine) but have heaps in the way of the radiator (like mine), such as spotties, intercooler, air con radiator, oil cooler etc, then air won't be getting in as effectively and efficiently and as such, you may not be cooling properly and think its mechanical/cooling system related when it is simply airflow restriction - like me, most people don't remove the obstacles listed above, and simply fit a colder thermostat ...

How'd I go Tony? Did I pass the test??!! lol

A colder thermostat won't increase cooling capacity, it will just open at a lower temperature.

As Robo says in post #8 running a colder thermostat can lead to enrichment issues on some engines, and you did have an issue with this last year when your engine coolant temperature sensor failed.

Colder thermostat's have their place but they shouldn't be used to mask short comings in the cooling system. Get the basics right first and if you need more cooling capacity do it properly with a higher capacity radiator and increased airflow. Short cuts will always come back to bite you on the ar$e.

Tony

[Bigrig]

A colder thermostat won't increase cooling capacity, it will just open at a lower temperature.

As Robo says in post #8 running a colder thermostat can lead to enrichment issues on some engines, and you did have an issue with this last year when your engine coolant temperature sensor failed.

Colder thermostat's have their place but they shouldn't be used to mask short comings in the cooling system. Get the basics right first and if you need more cooling capacity do it properly with a higher capacity radiator and increased airflow. Short cuts will always come back to bite you on the ar$e.

Tony

Not quite true boss - temp sensor was Christmas 2010 ... A loooonnnng time before I had the new radiator, cooling system flushed, and cold thermo put in ... on that side, never had a problem since with the cooling system. Just with everything else!!!! lmao

[YNOT]

Not quite true boss - temp sensor was Christmas 2010 ... A loooonnnng time before I had the new radiator, cooling system flushed, and cold thermo put in ... on that side, never had a problem since with the cooling system. Just with everything else!!!! lmao

True. The point I was trying to make was you've seen what can happen with enrichment, in your case it was caused by a faulty sensor not a cooling system issue

Tony

[Bigrig]

True. The point I was trying to make was you've seen what can happen with enrichment, in your case it was caused by a faulty sensor not a cooling system issue

Tony

All good boss - it doesn't seem like over a year ago does it??? lol

[YNOT]

All good boss - it doesn't seem like over a year ago does it??? lol

No it doesn't, where does the time go?

Tony

PS, thread hijacked by 2 moderators!

[Bigrig]

PS, thread hijacked by 2 moderators!

All for the common good though!!!! lmao

[vbowste1]

Well i have bought an intercooler of e bay its a bar and grill type aluminium but i tried to be conservative and only got a small one, 450x300x70 as i didnt want to completely cover the other radiators with it.
The reason i didnt go big was the fact that a mate just bought a ford ranger and it is intercooled with a small size one so i thought it must be ok as the new cars are only using fairly small ones so they must work ok.
I will fit that as well as a 3inch exhaust, reconditioned injectors get the radiator flushed out by pro's and see how she goes. Oh yeh and i was going to fit a boost guage and boost adjust valve and try and turn it up a bit.
Thanks for the help ill let you all know how it turns out.

[Bigrig]

Well i have bought an intercooler of e bay its a bar and grill type aluminium but i tried to be conservative and only got a small one, 450x300x70 as i didnt want to completely cover the other radiators with it.
The reason i didnt go big was the fact that a mate just bought a ford ranger and it is intercooled with a small size one so i thought it must be ok as the new cars are only using fairly small ones so they must work ok.
I will fit that as well as a 3inch exhaust, reconditioned injectors get the radiator flushed out by pro's and see how she goes. Oh yeh and i was going to fit a boost guage and boost adjust valve and try and turn it up a bit.
Thanks for the help ill let you all know how it turns out.

Good stuff and good luck with it mate.

[Robo]

Yeah mate if the intercooler is to big I'm told you can have pressure drop any way,and the manufacturer should be able to tell you it's flow rate.
I have a calc somewhere to help work out an engines N-A air flow volume rate, but recon if a turbo is thrown into the mix you would need to take boost into affect, my point is, there is probably a calculation for working this out, I just don't have it to pass on. someone out there may?.
Cheers

[Bigrig]

I have a calc somewhere to help work out an engines N-A air flow volume rate, but recon if a turbo is thrown into the mix you would need to take boost into affect, my point is, there is probably a calculation for working this out, I just don't have it to pass on. someone out there may?.
Cheers

It's called a dyno!!!! lmao

Would be bloody good thing though - after fitting my turbo, all the thoughts would be that the standard air box wouldn't be up to the task and would starve it of O2 somewhat - now on the analyser, I've got both unburnt fuel AND oxygen coming out the pipe whilst we try to get it humming (still at the mechanics) ... obviously need to alter a few things, but at least I'm a little more certain that's it's getting enough now. Would be nice to be able to calculate it at the outset as some would just go out and spend their hard earned on a new air intake setup just because of uncertainty ....

[YNOT]

Yeah mate if the intercooler is to big I'm told you can have pressure drop any way,and the manufacturer should be able to tell you it's flow rate.
I have a calc somewhere to help work out an engines N-A air flow volume rate, but recon if a turbo is thrown into the mix you would need to take boost into affect, my point is, there is probably a calculation for working this out, I just don't have it to pass on. someone out there may?.
Cheers

This is not exactly what you are looking for but may be of some help, check this website; http://www.turbobygarrett.com/turbobygarrett/charge_air_cooling

Tony

[YNOT]

It's called a dyno!!!! lmao

Would be bloody good thing though - after fitting my turbo, all the thoughts would be that the standard air box wouldn't be up to the task and would starve it of O2 somewhat - now on the analyser, I've got both unburnt fuel AND oxygen coming out the pipe whilst we try to get it humming (still at the mechanics) ... obviously need to alter a few things, but at least I'm a little more certain that's it's getting enough now. Would be nice to be able to calculate it at the outset as some would just go out and spend their hard earned on a new air intake setup just because of uncertainty ....

If you want to know if your airbox or snorkel are restrictive do a dyno run with and without them, if there's little difference they're not restrictive.

Tony

[Bigrig]

If you want to know if your airbox or snorkel are restrictive do a dyno run with and without them, if there's little difference they're not restrictive.

Tony

Really? Do you really think I'm going to rip them out? Especially at $140 per hour whilst it sits on the machine? Have you even ever met me?? lmao

[97_gq_lwb]

I just fitted a zd30 gu airbox into my gq apparently they work quite well.

[Robo]

I know this isn't really relevant here, but this came to mind reading thread.
My 89 Gtr came with fairly smallish looking air box and filter about the same size as the 1.8 Lt 97 lancer we had at the time.I had fitted twin pods 3 times the filter area.
now you would think this std set up restrictive with twin afm attached to box but my engine builder/ dyno man informed me he tuned 1 to achieve over 300 KW atw with std filter, with the Garrets I had, no value in $500 twin pods go figure that. Always learning.
Wish I had his R33Gtr, 700 kW atw. what fun!!.

maybe try disconnecting at point where snorkel meets inlet inside bay and compare against connected.
but this only figures for a no ram affect snorkel standing still, unless someone can aim a fan at snorkel intake and measure wind speed to determine power factoring wind speed to h power at predetermined speeds..
still stuffing around to find out as you noted. but would't you just love to know !.
or the other approach is contact snorkel manufacturer and ask flow rates for it and you can maybe check against motors current needs.
Bottoms up.

[Robo]

If ya want I can find calc for working out air flow of N-A engine, this helps for working out max size carby, cfm figures so not to drown engine or restrict, no good here I know, may help someone down the track.
And nice one Tony, the Garret link looks like a great read.

[White Elephant]

Well i have bought an intercooler of e bay its a bar and grill type aluminium but i tried to be conservative and only got a small one, 450x300x70 as i didnt want to completely cover the other radiators with it.
The reason i didnt go big was the fact that a mate just bought a ford ranger and it is intercooled with a small size one so i thought it must be ok as the new cars are only using fairly small ones so they must work ok.
I will fit that as well as a 3inch exhaust, reconditioned injectors get the radiator flushed out by pro's and see how she goes. Oh yeh and i was going to fit a boost guage and boost adjust valve and try and turn it up a bit.
Thanks for the help ill let you all know how it turns out.

I'm very interested to see how you go about this, I have been toying with the idea of fitting an intercooler to my RD28T for some time, I will keep my eyes on this thread! Good luck with it.

[Ben-e-boy]

I like this thread. The poor guy came with 3 issues, alot of the resonces are dribble about petrol engines and left with an cheap intercooler

problem solved