Aluminium radiator

[boldy205 75]

Hi all.

I'm looking improving the cooling on my GTi6 205 with a rotrex charger. 

My question is, does a full aluminium radiator help cool more effectively than a standard (Nissens) rad?

I appreciate the Nissens is already an aluminium core, but end thanks are still plastic.

 

Thanks

 

Matt

[Tom Fenton 1,541]

In my experience no not really. The only really big step change I found was fitting the turbo diesel 205 radiator, coolant capacity is a lot bigger and the car in question stays cool without hassle.

[boldy205 75]

Hi Tom. Thanks for the reply, nice to hear from someone who has tried it

Without a massive re jig of the radiators in the front, I think I will struggle to fit anything bigger.

When I have the car back I'll look into ducting what I have, as well as I can and go from there

[Tom Fenton 1,541]

The TD rad isn’t massively different footprint wise to the GTI rad, it’s just thicker. I hear you about making space though as with an intercooler and oil cooler it does get busy.

[SRDT 175]

Radiators for cars with A/C should have a thicker core but they still fit with the sandard radiator shroud unlike the TD rad.

[petert 586]

AC radiators are the same thickness and approx 15mm shorter, as they have to accommodate the condenser. Strange but true.

 

I just had a custom radiator made by PWR in Brisbane. They make 90% of the F1 radiators. It’s basically a Sierra RS500 copy.

 

My friend Parry uses an SR20 conversion radiator. I’ll see if I can find it on ebay.

 

This:

https://www.ebay.com.au/itm/402953100474?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=JE_GPU9HRu-&sssrc=2349624&ssuid=7N9vItgJTR2&var=&widget_ver=artemis&media=COPY
 

I made a few necessary changes with the TIG welder.

Edited July 15, 2023 by petert

[SRDT 175]

The A/C rad is smaller... did they use a better type of core or something? I know they had metal end tanks.

On a 309 the rad is a whole 10mm thicker.

[boldy205 75]

Hopefully the car will be back from mapping on Monday, do I'll have a good look and see where I can improve.

[petert 586]

10 hours ago, SRDT said:

The A/C rad is smaller... did they use a better type of core or something? I know they had metal end tanks.

On a 309 the rad is a whole 10mm thicker.

I don't think there's any difference in thickness. I'll measure one and get back to you. It's currently at a friend's place. The originals were all full copper/brass.

Edited July 16, 2023 by petert

[welshpug 1,657]

Most of the time its the big heatsoak sandwich that causes issues on the boosted cars,    standard rad works fine on an n-a application.

[SweetBadger 94]

Radtec can do a 50mm core version of the std rad.

 

They built one for my race car which was running hot with a nissens rad, did the job nicely.

 

https://www.radtec.co.uk/

 

They must have built it to the ac spec as it was shorter than std.

 

if you use them, and you want it to fit the std cowl then make sure you provide them with the correct dimensions, and remind them to offset the mounting pins at the bottom - if they are centred on a thicker rad then they are too far back for the std holes on the cowling. 

[SRDT 175]

12 hours ago, petert said:

The originals were all full copper/brass.

Probably "hot countries" rads, also used on cars with automatic gearbox or power steering.

The bottom spacers are not the same for radiators with brass end tanks so even with multiple part numbers they should all be more or less the same size.

[boldy205 75]

Thanks for the replies. I've got the car back now. Looks like I may have enough room for a diesel rad, so I'll try that. I'll also get some thick rubber sheet to try and create some ducting into the coolers 

[Tom Fenton 1,541]

Blocking holes off that allow air to bypass the radiators will help a lot. Just so you don't buy the wrong thing, its the TURBO DIESEL 205 rad you want, the diesel rad is the same as GTI.

[boldy205 75]

As in the 1.8 TD? 

[boldy205 75]

[boldy205 75]

This is the one I can find, however my current GTi rad is 610X288 (core size, no end tanks inc in that measurement) so this Diesel one I'd too wide.

[Tom Fenton 1,541]

That looks right, it will fit, but not in the standard cowling, you would have to make some brackets 

[petert 586]

The more I think about this, the more I must be wrong. ie the AC radiator has to be 15mm higher, as it angles away from the top to the bottom.

[boldy205 75]

1 hour ago, Tom Fenton said:

That looks right, it will fit, but not in the standard cowling, you would have to make some brackets 

Thanks for confirming it's the one, Tom.

I've found a supplier, they want £240. Seems hilarious that it's always the expensive one I need!!

[Tom Fenton 1,541]

To be honest I'm pleasantly surprised that its still available. They were scarce some years ago.

[boldy205 75]

At least that explains it then I guess. Still a sight cheaper than more modern stuff I'm sure 

Cheers!

[welshpug 1,657]

TD rad uses a different fan cowling, might have one to hand if you go down that route.

[boldy205 75]

17 minutes ago, welshpug said:

TD rad uses a different fan cowling, might have one to hand if you go down that route.

Thanks, however, my rad is mounted on some custom brackets so I'm not using an original cowling.

[petert 586]

AC radiator is 295 high and 42 thick.