Gen-1 twin inlet radiator mods

[asteroid500]

Hi all,
ive made my Gen-1 radiator a twin inlet and a 19mm outlet

1st remove the standard 250 outlet pipe.


The lower outlet pipe you have just cut off will now become your new top right out let.
I dummy fitted (test fitted) the radiator to determine where to drill my hole & to make sure it cleared both the frame & the radiator cap housing.
then using a chrismas tree drill bit i slowly cut out the hole with a cordless drill.








I marked out what angles i wanted so as to weld the old outlet in its new place.



The new top outlet inplace. i dented the pipe closest tyo the frame to give me enough clearance.





Now with the lower 19mm outlet i machined up an outlet exactly to the dementions of the waterpump outlets so the water hose wont blow off.
were your smaller 250 outlet was ( you will now need to enlarge this hole to accept your new larger diamiter outlet pipe, i used a die grinder to achieve this, use plenty of WD-30 or equivelant lubricant or your die grinder will bind on to your radiator and go BBBRRRRRRRRRZZZZZZLLLLE,
It dont tickle.




Now to check to see were you want your new pipe to exit.
I chose to place mine on quite a sharp angle so as to reduce the radius on my new water hose.



Once all is marked out to were you want your new outlet to go you can weld it in place.









the final out come



I cant say if it will cool any better, but i would rather have the twin inlets then a y piece joiner.
I'm also of the opinion that having the 19mm outlet at the same size as the water pump inlet and outlets will create a much better water flow and heat disapation aiding in a cooler running engine.

[CR500R7]

Job well done man, that leaves nothing to the imagination with the pictures.
I really like the twin inlet idea and the angled outlet.

[asteroid500]

thanks R7,
the welds arnt as good as some but i'm learning to TIG weld alloy...it's hard.

[gregrobo]

if your welding ali radiators like that your doing fine thin ali is the hardest to do and when its stamped you tend to get thin spots in the corners well done

[DitchWitch]

Nice job, but I wonder if flowing too much water will be worse for cooling? Maybe the water will flow through before it has a chance to transfer the heat into the radiator? Not saying it will but just a thought? Because your cooling surface is just the same.

[towman910]

looks

[CR500R7]

if your welding ali radiators like that your doing fine thin ali is the hardest to do and when its stamped you tend to get thin spots in the corners well done

X 2

You are just learning, Man it looks great, fantastic job!

[CR500R7]

Nice job, but I wonder if flowing too much water will be worse for cooling? Maybe the water will flow through before it has a chance to transfer the heat into the radiator? Not saying it will but just a thought? Because your cooling surface is just the same.

How could it be flowing to much water, when it is running through the same water inlets and outllets as a CR500 has, same water pump also pump inlet and outlet, the same outlets on the head, same hose and outlet size from the radiator to the water pump, same hoses going to the radiators.

All of the above would act as restictors to prevent it flowing any faster even if everything else was bigger, I can't see any of what he has done being a problem.

[asteroid500]

remember guys i race commodore cup,
and ive been involved in car & kart racing for a long time.......overheating is a huge problem and ive always for some reason had engines that ran hot.




you quickly learn the tricks when your forking over thousands of dollars for a radiator to take the sting out of your hot motor..(the Territotys a hot & humid place).

The CR-250 radiator has a top & bottom outlet pipe (the bottom 1 is removed) of about 14-15mm.
The CR-500 has twin out lets on the head of about the same diamiter.
The way i see it if you have to inlets running to the top of the radiator of 14-15mm and only a 14-15mm outlet on the bottom this is a restriction.

In a way the location of the inlet on the water pump dictated the new lower radiator size, a single piece of hose is all that is required to transfer the coolant from the radiator to the pump with no veriants in the pipe size this to is a single size application, no cuting and shuting different hose's.

Thats why i say it's a High Flow radiator, the coolant completes it's cycle with littel restriction, i'd even say the water pump would have a better time of as well.

[Roostius_Maximus]

i'd have restricted the RH inlet to 1/2 or less of its size, otherwise the LH will be hot.
you should now make some restrictors you can slip in the hose to try that, but what you have right there is like running a single small rad

nice job welding that thicker tube to that tank tho

[asteroid500]

Valid point Roosty...how are ya any way mate.
That sounds plausable to me...do you think that me having to press the top right tube (squash it) would be serfice, it would be atleast a 10-15% reduction in water flow.

Any one elses thoughts.

[AlisoBob]

I would rather have the twin inlets then a y piece joiner.

X2

[asteroid500]

thank you Bob

[britincali]

Its gotta be better than a Y splitter but Ive got to admit I dont have any cooling problems with my AF.



I would have probly spent the time straightning out the fins that have got to be increasing the temp......

[asteroid500]

Fair enough to i guess but if you can do, it like in my case i did it....
It's always veryb Hot & HUMID in Darwin, humidity is harder on engines then a generaly hot day