Engine

[maverick]

Ok so i am new to the website so hello to everyone and thank you for all you help in advance.

I am about to buy my first Morris Minor with a 1275.
I dont no whether i am being ambitious or not as i am not very knowledgeable, but i would like to make around a 100bhp.
What i would really appreciate would be a little advice on what i need in order to achieve this and how much it would all cost. I would do all the work myself as i am keen to learn and am very interested in cars. (i am currently doing my first year degree is Motorsports engineering lol)

Thanks
Tom

[mike.perry]

You only need another 45 BHP, that should be enough to wreck the standard gearbox

[PSL184]

100 BP = Very ambitious unless you undertake some serious engine mods. Additionally the rest of the drivetrain will need uprating too, as Mike says, gearbox won't take that kind of power on a regular basis and neither will the diff or the half shafts. It is possible - but will be expensive...

[Matt]

My engine developed about 85hp before I broke it

It was a 1275 bored to 1330cc with a kent 276 camshaft.

For 100hp you would need to bore to 1380 and have a higher compression ratio (skim the head or find flat top pistons or both) and a wilder cam.

I dont think 100hp is viable for a road car with a A series engine.

You would need a stronger gearbox and axle as mentioned above (probably type 9 5 speed conversion, and an escort mk2 axle) however a marina gearbox and axle will cope quite happily (its what ive got at the moment).

You will also need a brake upgrade.

[Onne]

Ask Cam on here, he has 120bhp if I'm not mistaken...

[bmcecosse]

100 bhp from 1275 is perfectly possible. You need a well modified BIG VALVE head - Cooper S if possible with the larger exhaust valve - and at least a 544 cam, but very probably the 649. A really good exhaust manifold and big bore system and twin 1.5" SU carbs (modified as per Vizard) on a GOOD (ie not the factory item) inlet manifold - or of course a 45 DCOE weber on a long inlet. If you want the engine to last - it needs to be fully balanced and centre main strap fitted, and have forged pistons installed - and an oil coller will be essential. You will definitely need a better gearbox etc as above.
If YOU want to last - you will need considerable improvements to the suspension and much better wheels and tyres - and most important of all - you will need MUCH BETTER brakes - front and rear!
100 bhp is about the max you can hope for from a 1275 A series. To get more involves special hardened crankshaft - and bigger bores - and considerable less reliability. Of course - the 'easy' route to more power is to install an Eaton supercharger ex MINI Cooper S - need low comp pistons and a good exhaust system, and of course that essential oil cooler.

[maverick]

Thanks for all your help.
Looks like im a bit ambitious then.
So what kind of bhp am i looking for if i didnt bore out the 1275.
Also what kind of engine conversion would be good for around the 100bhp mark without being to expensive. if i decided to go down another route. sorry for all the questions.
Also you say that the easy way to power is an eaton supercharger how much would it be to have a full working supervharged 1275 (just for parts, roughly)?

Thanks
Tom

[bmcecosse]

You can quite easily bring a 1275 up to 75/80 bhp without too much expense. MG Metro head + MG Metro cam + MG Metro carb and manifold. Add a decent exhaust and you're there. £150 for the MG bits (ebay etc) plus the exhaust - cost for that depends if you can modify a cheap Mini system or have to buy new.
Eaton -look on ebay for the charger - then you need to make or buy the adapter parts etc. Probably need to budget at least £500 assuming you do most of the work yourself.

[maverick]

Sorry to be a pain but What kind of exhausts should i be looking for? I would look for a new one.

[bmcecosse]

A nice large bore Long Centre Branch manifold - (try Maniflo for example although others do them too) and then a straight through system to take it to the rear of the car, or out to the side which is easier!