Engine recommendations please...
Discussion
Hi everyone - first post on here and it seemed the best place to pick brains about my first Mini restoration. The Rio has just tripped into 6 figures (and caused remarkably few problems in all that time 
) and it's time to give it a bit of TLC. My idea is to make it into more of a GT, so decently nippy but not banzai acceleration, and the ability to sit at 90mph for a full tankful of fuel without shaking the occupants to pieces would be more like it, and preferably not so highly tuned that it needs stripping twice a year! While I'm happy to get my hands dirty looking after it, an engine rebuild is beyond my expertise at the moment, and so I'd be buying a complete unit. I'm budgeting around £8k for the whole job (sounds a lot, but ICE is my specialty and there are serious plans for that...
) so I'd be happy to go up to £2000-2500 for a good engine/gearbox. I should say that I want to stay with an A series derivative rather than any other - wouldn't really seem right otherwise! Any recommendations from personal experience? A quick flick through the magazines just told me that there are a lot of people doing all sorts of engines 
so a recommended few to contact would be very helpful. Thanks!
Rich
ps - should say that I'm in Cambridge/Newmarket area if by chance you know any in this neck of the woods
>>> Edited by DrFeelgood on Monday 4th April 18:15
) and it's time to give it a bit of TLC. My idea is to make it into more of a GT, so decently nippy but not banzai acceleration, and the ability to sit at 90mph for a full tankful of fuel without shaking the occupants to pieces would be more like it, and preferably not so highly tuned that it needs stripping twice a year! While I'm happy to get my hands dirty looking after it, an engine rebuild is beyond my expertise at the moment, and so I'd be buying a complete unit. I'm budgeting around £8k for the whole job (sounds a lot, but ICE is my specialty and there are serious plans for that...) so I'd be happy to go up to £2000-2500 for a good engine/gearbox. I should say that I want to stay with an A series derivative rather than any other - wouldn't really seem right otherwise! Any recommendations from personal experience? A quick flick through the magazines just told me that there are a lot of people doing all sorts of engines so a recommended few to contact would be very helpful. Thanks! Rich
ps - should say that I'm in Cambridge/Newmarket area if by chance you know any in this neck of the woods
>>> Edited by DrFeelgood on Monday 4th April 18:15
Do the engine build yourself.
I can't comment about comfort as mine are fully stripped out Wear earplugs!
The safe bet is a 1380 engine with a 276 cam, stage 3 head and 3.2 final drive (with 10"s, 3.44 with bigger ones). That is what everyone else does, oh and a HIF carb (x1).
For your engine budget, you should (if you do the work yourself) see you mounting up a BMW supercharger on that and having about 30% more torque than the best KAD engine! It will pull 135mph with a 2.76 final drive.
I can't comment about comfort as mine are fully stripped out
Wear earplugs! The safe bet is a 1380 engine with a 276 cam, stage 3 head and 3.2 final drive (with 10"s, 3.44 with bigger ones). That is what everyone else does, oh and a HIF carb (x1).
For your engine budget, you should (if you do the work yourself) see you mounting up a BMW supercharger on that and having about 30% more torque than the best KAD engine! It will pull 135mph with a 2.76 final drive.
Supercharger eh? Hadn't thought of that! Is that within a DIY solution? I've changed subframes, suspension and brakes, and routine maintenance stuff, but never built an engine before 
What do you reckon the reliabilty of a supercharged A series built by a mechanical numpty would be 
? As there's no time factor in this project (other than the obvious impatience!) I suppose the logical (and therefore unlikely) route would be to rebuild a knackered engine for practice. However, once impatience sets in, and I've lost the thrust doodah behind the blue sprocket of death, and I just want my Mini working again, who would you call? I have a feeling my life is about to change direction....
What do you reckon the reliabilty of a supercharged A series built by a mechanical numpty would be ? As there's no time factor in this project (other than the obvious impatience!) I suppose the logical (and therefore unlikely) route would be to rebuild a knackered engine for practice. However, once impatience sets in, and I've lost the thrust doodah behind the blue sprocket of death, and I just want my Mini working again, who would you call? I have a feeling my life is about to change direction....
It's more confidence and common sense really.
To build a more high performance engine does require lots of accurate measurement and careful assembly. For example, you must calculate the comp. ratio you want and get the combustion volume correct. The cam must also be accurately timed in as well. Crankshaft end float is critical too.
Once you become used to these things it's relatively straightforward.
The problem is that it's not possible to build a good engine which is also a cheap engine. For best results you must buy the best parts, like really good pistons. For example, I've just paid £80 each for a set of Karl Schmidt for my 'S'. However, the last set did 28 rallies and still looked really good when taken out. It is bore wear which dictates a re-bore.
Someone once asked me how cheaply I could build them a rally engine. The answer was "I can't".
Maybe that's all easy for me to say as I have built so many over the last 40 years, but I still find it enjoyable.
Some of the rubbish the so-called 'professional' builders turn out is disgraceful too. I once bought a ready-done gas-flowed head for a 1071 rally engine. the head modifier was given all the dimensions and the required volume. When I received the head I took the trouble of measuring it and they had done it for a 1275, not a 1071. This meant stripping and milling it to get the correct C.R. If I had assumed they had done it correctly I would have had a 1071 with a race spec, but with about 8:1 C.R.
To build a more high performance engine does require lots of accurate measurement and careful assembly. For example, you must calculate the comp. ratio you want and get the combustion volume correct. The cam must also be accurately timed in as well. Crankshaft end float is critical too.
Once you become used to these things it's relatively straightforward.
The problem is that it's not possible to build a good engine which is also a cheap engine. For best results you must buy the best parts, like really good pistons. For example, I've just paid £80 each for a set of Karl Schmidt for my 'S'. However, the last set did 28 rallies and still looked really good when taken out. It is bore wear which dictates a re-bore.
Someone once asked me how cheaply I could build them a rally engine. The answer was "I can't".
Maybe that's all easy for me to say as I have built so many over the last 40 years, but I still find it enjoyable.
Some of the rubbish the so-called 'professional' builders turn out is disgraceful too. I once bought a ready-done gas-flowed head for a 1071 rally engine. the head modifier was given all the dimensions and the required volume. When I received the head I took the trouble of measuring it and they had done it for a 1275, not a 1071. This meant stripping and milling it to get the correct C.R. If I had assumed they had done it correctly I would have had a 1071 with a race spec, but with about 8:1 C.R.
Scince my last post plans have changed. Not going to bother re-buliding my old engine just yet as I have just bought a Bog standard 1.3 metro with 40000 miles that I will swap over together with the vented disks(2 new task for me).
Any Ideas as to what head is on this and is it any good? (Firt reg 1990)
As the engine is good with no leeks I am reluctant to just pull it apart to find out.
Any Ideas as to what head is on this and is it any good? (Firt reg 1990)
As the engine is good with no leeks I am reluctant to just pull it apart to find out.
The head will, of course, be the 12G940, but as to valve sizes it's anyone's guess. Maybe it would be a good idea to take off the head, fit a BK450 gasket, check the valve sizes and, maybe, fit the 35.5mm inlets if it doesn't have them. Re-lap the valves in. You could replace the valve guides and seals at the same time, then your engine should give improved performance. Why not skim a bit off the head to increase the comp. ratio and ensure the head is nice and level?
With the head stripped you can make useful improvements to the gas flow just by opening out the throat area a bit and reducing the valve guide bosses in the throats as these really do restrict flow. Make sure the 'short-side radius in the throad is nice and smoothly blended in.
It's so easy to change things whilst the engine's out, like the timing chain, water pump, clutch plate and 'red' seal. It depends how far you want to go. For example, I always fit a duplex timing chain, but this involves a small mod to the timing cover on Metro 1275 units.
The trouble is, it's hard to know where to stop and you can end up saying that you'll just take the engine off the box, change the big-end and main bearing shells, cam followers and oil pump. Then you have a virtually all-new engine, especially if you change the piston rings as well.
Endless, isn't it?
With the head stripped you can make useful improvements to the gas flow just by opening out the throat area a bit and reducing the valve guide bosses in the throats as these really do restrict flow. Make sure the 'short-side radius in the throad is nice and smoothly blended in.
It's so easy to change things whilst the engine's out, like the timing chain, water pump, clutch plate and 'red' seal. It depends how far you want to go. For example, I always fit a duplex timing chain, but this involves a small mod to the timing cover on Metro 1275 units.
The trouble is, it's hard to know where to stop and you can end up saying that you'll just take the engine off the box, change the big-end and main bearing shells, cam followers and oil pump. Then you have a virtually all-new engine, especially if you change the piston rings as well.
Endless, isn't it?
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