Keith Calvin wrote the following.......

Radiators. No amount of tweaking the rest of the cooling system will help if there simply isn't enough cooling capacity in the radiator. Water capacity used to be the answer, hence the production of four-core radiators. It's possible the improvement in cooling was a product of more surface area created by the extra tubes, but the inefficient airflow through the congested radiator area reduced its ultimate effectiveness. In reality, effective surface area's the answer, and why the latest after-market, super-efficient two-core radiators are the best. The standard radiator can just about cope with a standard engine in most cases. The exception appearing to be the fuel injected cars. They'll stand the limited modifications that can be made without problems. Perhaps it's the 'brain' compensating for it somehow in trimming ignition and fuel? If you're significantly increasing the power output, I strongly advise fitting one of the aforementioned two-core radiators. And ALWAYS have water flowing out of the heater tap take-off. If no heater or auxiliary matrix is used, plumb it into the top hose. If it's put back into the bottom hose it won't work properly, if at all. The water going into the bottom hose at that point MUST be below that in the main hose coming out of the radiator.

So how does the heater work if the water is plumbed to flow back to the top hose? I presume there would be very little flow to the heater in this case?

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Chris

Everything I like is either
illegal, immoral or fattening.

My reading of that is "if a heater IS NOT fitted" plumb back to the top radiator hose. In other words a heater helps with cooling

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Short answer... it won't.
Barney's 1293 has a new 2 core rad with no heater, but a hose from heater outlet on head to bottom hose.

No problems yet.

On a MiniMatic, this water circuit is connected at all times thru the freshair heater, heater on or not. There's no tap.
And, the drivers handbook states the heater is an integral part of keeping the little sucker cool- do not remove..

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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.

Kev, I'd recommend you change your set up on Barney. If no heater or heater core is used, then water from back of the head should go to the top tank or top hose. If a heater core is used, then this water can go into the bottom hose. Idea is, and KC says this but not clearly in last couple of sentences, water temperature going into bottom hose needs to be lower than what's there. If you take it straight from the head to the bottom hose, this water is hotter than that coming from the rad. You are just recirculating the hot water which means it will just keep getting hotter. Steve

Yes I understand that Steve. There is a MiniMatic heater sitting on the garage floor, which will go in there real soon.

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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.

after pulling my entire heating system out and then to bits, I found that the neat little heater core (mini radiator) would be perfect to fit in the front grill, and to plug it into the existing heater hoses inline would be pretty simple. It wont help though unless the heater is turned on. Is there a way of using another heater core to suppliment the existing radiator, that helps the cooling even if the heater is not turned on?

Im guessing the only way to do that would be to plug it in somewhere in between the bottom radiator hose and the radiator?? But that definitely wont be easy

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78 van 1300 cam extractors weber, 12" Superlights Metros Konis HiLos MP3 Amp Sub Alpine speakers and lots of fur
www.crazybitchracing.com

Just leave the heater tap on, and the air lever off in summer, & it should work fine with both cores plumbed in series..

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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.