[RickGQ]

Maybe a dumb question... But I've been told it's dumber not to ask...

Has anyone used a parallel feed (ie not serpentine) A/C condenser as a W2A heat exchanger?
Many have a nice surface area and are quite thin, as thin as 16mm, which would fit like a dream behind a GQ grille. The tube spacing may be too dense for good airflow though.
For Example:

AC CONDENSER FITS HOLDEN COMMODORE VE series 2 6.0 V8 2010-2017

Features: Brand New and Good Quality Material: PU Leather -Width: 65cm/25.6" -Length: 47.5cm /18.7" Universal fit for most of cars Quantity: 1 Pieces Color: Coffee Model : Standard 1. The organiser fixed by adjustable straps and buckles is stable enough. 2. It is not only a car organiser, but...

redbox.shop

A/C CONDENSER fits HONDA JAZZ GE 1.2 1.3 1.3 HYBRID / 1.5 PETROL 2008-2014

Fit: 2008-2014 HONDA JAZZ GE 1.3 / 1.5 PETROLCore Size : 744 x 327 x 16 mm Model: 1.2i 16V Transmission: Manual Engine: L12B1 Inlet/ Outlet: 10.2/15.5mm Material: Aluminium

redbox.shop

In the end, I think, the MR2 radiator may be the best option. The commonly available Ebay ones are priced right and are 34-40mm thick (they call it 2-core) with an 8-10mm tube spacing, which is pretty darn close Oldmav's recommendation.

The Barina radiator has a great core size, probably ideal, but the plastic tanks are a pain.

 

[RickGQ]

Ok... so I got a new Barina radiator from Ebay for a bargain price, as an experiment. The core area and thickness is good for a GQ but as expected the plastic tanks are almost impossible to work with. The core seems a bit dense as well, air may not freely pass though it, that'll affect the main radiator performance. If I had my own Tig set-up as well as the expertise I'd make my own tanks and try if out. Too many 'if onlys' there though.

So, we move on.

Got an MR2 full alloy radiator from Ebay. There's a lot of these on Ebay, some better than others. This one looks good to me. Overall height is 340mm, core is 320mm high and 35mm thick. Tube spacing is just shy of 10mm as recommended by @OldMav. Tanks are 320mm high, same as the core, so if I need to trim the frames the tanks won't get in the way. There are drain and bleed points top and bottom, so it'll be easy to bleed air out of the system. The tanks are thicker than the core at 45mm but that may apply to all these MR2 radiators. Welds look very neat. The rad has been painted a silver colour, looks nice but will need to be stripped back wherever welding is required.

Next move is to see how well it fits. A few of the pegs and brackets will have to go and of course the coolant inlets will need to move. Patrol has some work to do over the coming week so ill have to wait a while before pulling the grille off.
Looking forward to the process though...

 

[RickGQ]

I'm really quite happy with this Ebay radiator. It was cheap to buy and the quality looks good. It's come down in price a bit since I bought it too.

The inlet and outlet will need to be moved of course.
I'm thinking I can cut them off and patch the holes.
Then, decide whether to re use them attached to the end tanks, or get right-angled fittings that would line up with holes cut in the radiator panel. The pipes are 32mm.

Perhaps I can use the existing mounting points on this thing. I can attach some angle to the bottom radiator mount and drill it to match the bottom pins.

The top mounting points should be easy enough to adapt. Either the 'saddle' or the 'loop'. Of course it'll need to look neat when completed.

 

[RickGQ]

I wish the a/c condenser was better designed. This stupid hard line gets in the way...

 

[james008]

I wish the a/c condenser was better designed. This stupid hard line gets in the way... View attachment 525836

The hard lines are very soft and thin wall tube, so in some areas they can be very gently massaged a small amount. I had to do that when fitting my condensor as the hard line was a bit bent.
I'm not sure theres much you could do with those curves and around the join though without risking breakage.

When I was considering using a front mount I wondered if it would be possible to find a more modern condensor to fit for better packaging and hopefully better efficiency since they would be designed for use in an R134A system rather than our old R12 system.

 

[RickGQ]

The hard lines are very soft and thin wall tube, so in some areas they can be very gently massaged a small amount. I had to do that when fitting my condensor as the hard line was a bit bent.
I'm not sure theres much you could do with those curves and around the join though without risking breakage.

When I was considering using a front mount I wondered if it would be possible to find a more modern condensor to fit for better packaging and hopefully better efficiency since they would be designed for use in an R134A system rather than our old R12 system.

Yes... there's aftermarket condensers that would fit in the space. Some of those are parallel rather than serpentine, parallel should be more efficient than serpentine.
Some work would be needed to fabricate the mounts.

That hard line on the genuine condenser could be moved to the side for maybe half it's length. The bit at the bottom that's welded to the serpentine would have to stay though. That's the bit which is causing inconvenience with the intercooler.
Lack of foresight on my part. I could have used a universal ac condenser and made custom, recessed hard lines.

Universal condensers and brackets:

Universal: Speedy Air Spares

Universal Condenser Mounting Brackets: Speedy Air Spares

Universal Condenser Mounting Brackets & Dampeners

speedyairspares.com.au

 

[RickGQ]

Today I had a go at fitting the MR2 radiator to the GQ.

Bottom support is 30x30x3mm alloy angle bolted between the existing slotted grille mounts. Those 1/4" roofing bolts will be replaced with M6 bolts and nyloc nuts once everything is sorted out.
The alloy is drilled to match the pegs on the MR2 radiator and nylon bushes inserted...

The MR2 radiator must be offset to avoid the a/c hard line on the condenser.
I really would like to find an alternative to that condenser, so the radiator could be centered properly. It would be better in every way.
I'm tempted to have a go at modifying the condenser, so the liquid line comes out the side. There's room to do it... If I have the skill to do it...

To fit the radiator tank on the passenger side, a few mm had to be ground away from the bodywork... If the radiator could be centered, this would not be necessary.

Once in place, the top of the MR2 radiator fits in line with the bonnet catch, with a 10mm gap to the surface of the a/c condenser... This is very neat.

Close-up. The fit at the top is almost perfect. That makes me happy.

With the radiator offset as it must be, there's very little clearance at the bottom passenger side. Only 15mm. The need to offset the rad really bugs me.

What remains now is to re-locate the pipes from the MR2 rad. First they must be removed. I read in the 'inlet manifold' forum, that an angle grinder should not be used on alloy because it introduces impurities that makes welding difficult?
That means I must use the MK #1 hacksaw and sweat it out??

Also need to think about pump location... A pump would fit inside the bullbar where the winch would normally go, and running a hose from the driver side tank to that pump would be neat and simple...

 

[RickGQ]

The MR2 rad/heat exchanger fits very well.
Had to trim a little off the inside of the grille, but once the rad is painted black the casual observer would never know there's a heat exchanger there. The grille looks factory from the outside.

 

[mistyv6]

work out were you want the inlet outlet to go and take the unit to your alloy welder to cut a normal angle grinder blade leaves aluminum oxide in the metal

 

[RickGQ]

Part of the preparation for the intercooler is accurate measurement of charge air temperature.
There's been a thermocouple in the crossover duct for years, but it's a heavy duty, fully sheathed EGT type and I have always thought response time and heat soak were making the charge air measurements less accurate.
So, last week I fitted a fast response exposed-tip thermocouple.
The difference in charge air peak readings was immediately obvious.
On a run to work, suburban driving, the charge air rarely got above 60 degrees with the heavy duty thermocouple.
Today, on the same run, the peak reading is 97 degrees.

Lessons learned:
1) We need the correct measurement device for the application
2) With air temps peaking that high, an intercooler is a priority.

 

[dan ahern]

Nice Patrol👌

 

[RickGQ]

Nice Patrol👌

Thanks Dan. I got it new in 1991 and it just keeps getting better.