cooling

[les]

Would like some advise/opinions as to the type of cooling system to use w ith an Ital engine, and will the midget flywheel fit the Ital crank, number of holes etc? Finally if a supercharger was used on this unit, apart from improving the breathing I am thinking that leaving it standard is the way to go, what do you think?

[Kevin]

Les why do you want to fit a Midget flywheel it takes a smaller clutch plate and can be quite snatchy in a Minor as I tthink its only 6 1/4" compared to a Minors 7 1/2" which gives a smoother action and should last longer.

[jonathon]

If thinking of fitting a supercharger then I wouldn't fit either clutch, but go for a Ford one to suite the Ford gearbox you will also need. Neither clutch , will be really suitable for the torque available from a supercharged 1275cc.
The Minor flywheel is the one to go for, but modified to Ford PCD fitment.
Cooling ,go for the most efficient, i.e alloy rad, fitted with some thin Kenlow 10" electric fans, there is plenty of room to fit these. Would it not be the case that you should lower the compression ratio with a supercharger. Also check the suitability of the pistons and conrods for the increased bhp/torque of the supercharger

[les]

Thanxs for replies, Kevin just thought the midget flywheel might have the 6 holes required, but if it's smaller then it's a none starter anyway! Jonathan, I am checking with the Ital site at the moment regarding the compression of the pistons as low would probably needed, I think the rods are considered pretty tough. I am considering the merits of a slightly modded 1275 verses a pretty standard engine with this blower, trouble is if I go for the former the latter would be a problem with the high comp pistons, so have to make a decision early.

[bmcecosse]

No - you can stick with the standard pistons - just adjust the blower pressure to keep it reasonable. Rods will be fine for blower or slightly modded engine. Good results from 1275 engine by fitting the Mg Metro head and a better cam (276 or 286) and the bigger 1.75" HIF 44 carb on the MG Metro inlet manifold. That would give ~ 80/85 bhp depending on cam used and assuming a decent exhaust manifold and system.

[les]

276 or 286? Are these Kent cams? Do you know the valve timings? Again you are a little vauge, as I'm still new to this supercharging thing, what is reasonable pressure for this engine you describe? Would like to know, but if you are not sure, please say so, as I need reliable info. Will look out for Metro head, I presume the valves are bigger?

[bmcecosse]

The early MG Metro head had a bigger inlet valve - same size as Cooper S (1.4") - and was ported to suit. The 276/286 refers to the valve timing - used for normal engines, but for supercharging the engines use very much less timing on the cam - generally just what was in there to start with - although sometimes increased exhaust timing to help clear away the burned charge, and sometimes with increased lift on both inlet and exhaust. The 286 for example is an excellent camshaft for a 'roadracer' engine - it's the old BMC 544 cam which started life as the Formula Junior race camshaft !! The 276 is slightly less dramatic and may suit you better - although I much prefer the 286, and acheaper but almost as good cam is the MG Metro camshaft which can sometimes be snapped up on ebay for ~ £15. These cams are produced by many companies - they all claim to be better than the others - you pays your money and takes your chances. You could just bolt a supercharger on the standard engine - but gear it down to limit the puff - this was the old way with the Shorrock unit and usually gave about 50% increase in power. Should not give any trouble if the engine is in good condition to start with - and the extra power is not used continuously - although top quality fuel with octane boost additive would definitely be a good idea.

[les]

Jonathan sent you a pm but didn't see it go. Have you received it?

[jonathon]

Hi Les, nothing yet!!

[bmcecosse]

To get back to your original Q - the standard radiator should fine provided you are not intending using the additional power continuously. However may be an idea to fit two fan blades - at right angles (obviously) on the water pump - or perhaps even the Spridget multiblade fan.

[Onne]

Or a Kenlowe (or similar) electric fan in front of it.

Merlin Motorsport do a really nice kit, which consists of a nice fan, choice of size, and a thermoswitch, which sits in the radiator, no welding/soldering required.

[bmcecosse]

Kenlowe is a pathetic wee thing and is really only designed to keep some air moving when stuck idling in traffic. The s-charger will generate extra heat when the engine is being hard pressed - so what's really needed is plenty of air whooshing through the rad at high revs - hence the extra fan capacity.

[jonathon]

Well I wouldn't say Kenlowe 'was a pathetic wee thing' we use them extensively on our tuned K series.I think BM you must have had limited knowledge /experience of these fans to make such a remark. You need to research the options available to you from the likes of Kenlowe as each fan has its own CFM measure. You will find that a 10" fan will suit most needs inc the likes of Fiat TC's and K series. We use two 9"or 10" fans when fitting uprated motors, even turbo's. The area you should look at is the efficiency of the radiator. We have very efficient alloy rads made for our conversions, and their thermal efficiency means that its size can be kept to a minimum. Again this rad will be used in my turbo K series,and thats with an intercooler infront of it.
The idea of the supercharger or turbo is to produce more power and torque at lower rpm than normal. We limit our K series normally aspirated engines to 7200rpm with most torque at around 4-5000rpm the turbo version, produces 200bhp and 210ftlbs of torque from 1400 rpm,peak power is at 5,000rpm. So really you don't need to rev even a 'standard' spec supercharged A series, let alone a 'modified' one

[bmcecosse]

Kenlowe (and others) have tiny wee electric motors - they obviously can't move much air - certainly nothing compared to the mechanical fan on the engine. They are fine for stuck in traffic idling - that's what they are designed for! Then when the car is moving there really is no need (normally) for a fan. I ran my Minor for years with no fan - and I also ran a Mini with no fan - just had to switch it off if not moving. But the concern here was for additional cooling - hence my suggestion of double blades as being the least expensive 'fix'.

[Onne]

If the electric fans are such weak things, why does almost every modern car use them? Even with a NS engine!

[bigginger]

In fairness, even Kenlowe say on their site that they're for cooling in traffic, though they do do all sorts of models.

[Onne]

Which is the only time the car needs them really.

I looked at the fans for race use btw

[les]

Electric fan seems cool!! Of course the standard item is fail safe.

[Onne]

Thats why I'd like one, just for curiosity

[jonathon]

With a supercharger, the main concern will be getting rid of the underbonnet heat rather than increasing the amount of air into the enginebay. The open frontal area allowing air in is more than sufficient. You also have the downside of the power that the supercharger drains the power of the motor just to run it. So if you are only using v.low boost you probably will not increase power and torque by much.
BM , we'll have to agree to disagree about fans, but I'd be interested in the research you have done to come to your conclusions.