Any advise please on a good radiator for an overbored and stroked 1275
Thanks in advance

If your not after a factory look it'd be best to go for a Alloy radiator, which one is something I don't know (but I do need one myself so I'll be watching this thread). On the other hand you can pick up a 3 core copper radiator that should handle the heat.

_________________
Respect mine and I'll respect yours.

I’ve gone for the Mini Spares-made alloy one with an 1100 cfm fan . I hope i’ve Made the right choice. Radtec in the UK or Race Radiators here would be the next step, but hoping the expense won’t be required.

_________________
Cheap, Fast, Reliable. Choose two.

Yes the more you bore the motor the bigger the problem becomes.
Would love responses from peeps running 73mm bore or more with success Thanks all .

I'm running a 73mm bore, std Oz 3 core radiator and Minimatic heater. With an 82C thermostat it sits on 80C/180F. Less on freeway as the heater acts as an auxiliary radiator.
Stock radiator is fine but get it cleaned out by a radiator shop.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I purchased multiple alloy 50 mm ebay items ( sorry local suppliers/ welders , i just couldn't justify 4 or 5 times the price) approx $90.

you need to measure your widths, as the cheap ones vary from about 51mm to 58mm. ( also check visually on the fall of the height from top rear to front as i have heard some rub the underbonnet.)

I run one in a race engine overbore but shortstroked ( 73.5x 76) , as doc mentioned, run a auxillary tank. ( i use the good old moke ones and as advised by a clever mini engine builder/racer, use it as a proper header tank not just an expansion tank) Others are in service in other race engines, so cooling power is excellent. Cheers Darryl

74 degree thermostat, Speedflow 6AN 3/8" Pushlock Aluminum Weld On Barb Alloy Fitting 989-406 ( good ally thickness for welding onto radiator neck in my instance)

these are the ones i used and am happy with for fit and purpose but probably lots and lots of similar....( welding of rad is actually very good as commented by the welder who welded on the barb fitting)
AUSTIN ROVER MINI 1275 GT 1959-1997 50mm ALUMINUM RADIATOR from worley parts on ebay

Anyone using a Mini Spares two core radiator?

_________________
Slide
1965 Mini Van (1360)
1970 Mk2 Cooper S (1310)
1978 Rover SD1 V8 (4.6)
1996 Land Rover Discovery V8 (4.0)

I had their 2 core one in Barney, a 1293A+ that made 59.4 HP atw. Pretty well made.
I found their 3 core Cooper one flimsy and it only had 8 fins/inch. Did not cool well. Maybe are better now, I dunno.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I have a minispares 2 core one in my car. It's now 4 years old and just started to weep a little on the top join. I bought the copper one as I was under the impression it'd last a lot better. It makes you wonder if it's worth getting fixed or just get a new alloy one?

_________________

I've had an alloy one for 4 years with no problems. Its Chinese apparently but the quality/ fit is very good. I don't know the brand, I bought it from a Mini specialist in Melbourne. It was very cheap I thought ($100 rings a bell). It cools very well and no sign of corrosion. I use a cheap auto spares coolant and it keeps very clean...

_________________
67 Deluxe
Dry suspension
1293cc, 11:1 comp, RE 282 camshaft, 45 Weber, extractors etc
4 synchro close ratio gbox
Cooper S brakes, no booster
Stealth box, as Doc says "goes harder and idles!"
RH tank cos I needed it crossing the Nullarbor etc..

Any more ideas or thoughts on this subject?

I'm using a 50mm ebay job. Motorkhanas all day on the hottest days and never a drama

_________________
did I tell you that I won a trophy?

I'm running the Mini Spares 2 core radiator on all 4 cars, and am very happy with the performance even on the hottest day. Expensive... but not when you consider the cost of replacing a head gasket or rebuilding an engine!

_________________
'66 Mk 1 Cooper S,
'69 Mk 2 Cooper S,
'81 Leyland Mini (in New Zealand),
'78 Clubman 'Special' (track car)

We purchased the MINI COMPETITION '2 CORE' HI FLOW RADIATOR (SUITS MORRIS) from Minisport and it's cooling just fine, even on a new 'Big Bore' motor.

'Especially for more powerful and hotter running engines. Developed using the latest technology and design for increasing air flow, utilizing just two rows of very large cores and V shaped gills, thinner than the 4 core, this radiator is perfect for the morris models as they fit with very minor shrould alterations'.

I'm using a 1275 California Moke factory 4 core radiator in my 1360 van with the top inlet at the back, and it seems to keep things fairly cool.

_________________
Slide
1965 Mini Van (1360)
1970 Mk2 Cooper S (1310)
1978 Rover SD1 V8 (4.6)
1996 Land Rover Discovery V8 (4.0)