Camshaft Design

Elgin Cams is a company that is a direct descendent of such famous California specialists as Isky, Delong, Winfield, etc. etc. Elgin has taken the art of cams into the science of the '90's. Computer designed and handcrafted workmanship guarantee a first class camshaft. Custom designed cams are a specialty. Part No Applications: CAM001, CAM002, CAM003, CAM004, CAM005, CAM006, CAM007 Elgin has made cams or sold his design to General Motors, Ford Motor Co., Nissan Corp., Zakespped International, Porsche Motor Sports, Winston Cup "Engine Builders. Elgin has the largest percentage of cams used at the SCCA Runoffs from GT-1 to Formula-V. He also has provided original or new technology for antique and vintage racers. Much information has been recorded about the four stroke internal combustion engine and yet only a small percentage of people really understand how it works and fewer people know how to modify an engine to suit their needs.

Cylinder head - What can easily be achieved

During a discourse with the editorial staff at Mini Mag, it was decided the build feature presented an ideal opportunity to demonstrate just exactly what such an engine build is capable of in days where it's generally believed you have to have an all-singing, all-dancing 1380cc engine to have an enjoyable road burner - leaving those with very limited budgets a little depressed. During a discourse with the editorial staff at Mini Mag, it was decided the build feature presented an ideal opportunity to demonstrate just exactly what such an engine build is capable of in days where it's generally believed you have to have an all-singing, all-dancing 1380cc engine to have an enjoyable road burner - leaving those with very limited budgets a little depressed. So the idea was to finish the engine off using a relatively 'mild' specification to maximise drivability. The camshaft used was the fantastically versatile Swiftune Racing SW5 profile that provides drive from nowhere up to 7,000rpm - d

Cylinder heads - About Min Tec Heads

'Modified to give maximum performance gain for cost. Combustion chambers, inlet and exhaust ports extensively re-worked. Stone-ground finish in ports promotes ultimate fuel atomisation. Terminology - VFM - Value For Money CR - Compression Ratio VE - Volumetric Efficiency Three-angle valve seats in head. Cooper S size valves with current maximum flow profiles and Tuftrided for durability/longevity when used with unleaded fuel (hence 'black' finish). Combustion chamber volume used to give slight static compression ratio increase over standard. Head mods employed greatly increase volumetric efficiency, boosting actual running (dynamic) compression ratio. Where much sportier cam profiles are used, a higher compression ratio is advised to achieve maximum power potential. Seek advice on what is required'. That is the opening paragraph from the fitting instructions sheet as supplied with the heads I do for Mini Spares.

Engine - 998 Tuning, Bolt-ons

The 998cc engine is a very robust and tunable unit. It is also the most common engine found in standard Minis. See bottom for useful part numbers Terminology: MSC/MM - Mini Spares Centre/Mini Mania ID - Inside Diameter OD - Outside Diameter BBU - Big Bore Unit (refers to all 1275cc-based units) SBU - Small Bore Unit (refers to all sub-1275cc units, here the 998) BHP - Brake Horse Power LCB - Long Centre Branch Despite the lure of the much-advertised 1380cc alternatives, many simply want to get a little more from what they have at reasonable outlay. The single biggest restriction on any standard Mini is the 'breathing apparatus' - anything that is connected to the induction and exhaust systems. The standard exhaust being the biggest culprit - it is desperately restrictive in the name of noise suppression and cheapness of manufacture. Oddly enough it also increases fuel consumption when tested over a better designed, fre

Injection - Tuning Update 03.14.03

This program of development embarked upon by myself and colleague Mike Barratt (MBE, Lincoln 01522 545189) was instigated by Keith Dodd, owner of Mini Spares centre. His instructions were for us ....

Air filtration - K&N Air cleaner test.

In the forefront of Mini tuning, improving the over-all breathing capability of the very asthmatic A-series the air filter set-up is one that sees priority attention. All the widely available (and widely varying) stage one tuning kits include at the very least a replacement - and hopefully - high-flow air filter element to fit into the standard plastic case,

In the past few years (well, must be nearly 6 years by now!) since I got involved with writing for the specialist Mini Magazines I have been continually fighting with the problem of limited space. This has limited what I have been able to cover, both in subjects and in details. Up until recently (say the past year or so) I have been covering fairly broad topics in a fairly broad terms and detail. Basically trying to cover perhaps the most popular areas dabbled in by the Mini owning masses.

Compression ratio - Basic considerations

I recently had one of my best mates to stay for a week. Don't get to see him very often, so when we're together we spend most of the time pontificating on all things A-series since he's a long-time Mini enthusiast too. Well, at least from a racing point of view. Anyway, of the various subjects covered one that prompted me into doing this little piece of verbiage was that of compression ratios (CR).

It's another for those subjects where folk can be heard waxing lyrical about their personal recommendations for CR levels, or stipulating hard and fast 'facts' about CR required for certain camshafts. And again, it's one of those generally misunderstood areas of engine tuning. So I'm going to try and cut through the haze a bit.

CRs are generally spoken about and quoted in reference to the 'static' ratio. That is a bunch of calculated or measured volumes calculated by means of an equation.

Cylinder head - Suitability basics

Whatever else owners do to their Minis by way of interior/exterior modifications or none at all, a very large proportion desire and search for an increase in engine performance.

See bottom for useful part numbers.

Now this may not be super-sonic speed-inducing power, it could just as well be for maximum economy. In either case, it's the engines volumetric efficiency (VE) under scrutiny - it's ability to breath in as much correctly proportioned air/fuel mix as possible in any given situation. Although the induction/exhaust system plays an important part, there are effectively two major factors that dictate performance increases - the camshaft and cylinder head. The induction and exhaust elements (stage one kits, exhaust systems, etc.) and camshafts are covered in various other articles in my 'Corner'. So here we'll have a look at cylinder heads and dispel some of the myths and legends surrounding them.

Engine - 998 tuning, bolt-ons (stage one)

The 998cc engine is a very robust and tunable unit. It is also the most common engine found in standard Minis. Despite the lure of the much-advertised 1380cc alternatives, many simply want to get a little more from what they have at reasonable outlay.

Terminology:
MSC/MM - Mini Spares Centre/Mini Mania
BBU - Big Bore Unit (refers to all 1275cc-based units)
SBU - Small Bore Unit (refers to all sub-1275cc units, here the 998)
BHP - Brake Horse Power
CR - Compression Ratio

To improve engine out-put, you need to increase the engine's 'breathing' ability. The stage one kit deals with all the easily bolted-on external parts, and represents the best increase for investment. From here on in the power increases will cost commensurately more money.

Engine - 1275, 95bhp sports/tourer test result

DIY enthusiasts often believe that building an engine to give excellent all-round road performance is beyond them. Mainly from comparisons made between what they have been able to achieve and what specialists say should be achievable from any particular type of engine build.

Generally scrambled further by the non-perfect match of parts and components used between aforementioned specialist and erstwhile DIY-er, and the ritual 'nose-tapping and knowing winks' display of those specialists. Something you can very nearly 'see' even when talking to such folk on the phone - or that inimitable 'ah, yes, well…' So some form of 'black art' is implied. Whilst there is most definitely a degree of 'feel' involved between the real specialist's results and those of just a good engineer - the bones of the deal is subject to no such thing and is certainly within the capability of the DIY enthusiast given the necessary information. And that has been the problem.

Engine - Metro engine identification data

The widespread and prolific fitment of Metro engines into Minis - usually those endowed as standard with small-bore (850/998/1098) engines - practiced in the UK has been spreading to many other countries worldwide.

So it's not surprising that the most commonly asked question has also become more prolific concerning the fitment of said engine - apart from actually how to manage the transplant and the differences in the installations, covered in articles relevant article on this site - is just which type of engine the individual concerned has bought or what they already have fitted to their car and is it worth keeping or junking. One initial question I pose often draws a pregnant silence whilst said inquiree scrambles their brains trying to find an answer for. Following that protracted pause, 'I dunno' is the usual answer. I then have to get into a lengthy explanation as to how to determine what said engine is.

Engine - Small-bore engine, 12G940 head fitting

There is no specific large-bore (1275cc-based) head casting number that will fit the 998 engine any easier than any other.

They all have the same problems - generally requiring exhaust valve relief cut-outs machined into the block and re-alignment of the front water gallery transfer ports. However, I would avoid using heads with valves bigger than 35.7mm on the intake since these are too big for most 998 engines unless they are absolutely full-race spec where top end power at high rpm is all that is required.

First of all it is worth checking that you actually need to make the relief cut-outs since some heads have a big enough head face to exhaust valve face clearance to allow fitment without the cut-outs when the standard cam and rocker gear is retained.

If possible, measure the actual valve lift you are getting with the current fitted set-up.

Engine transplants - Ancillary parts

Engine mountings are a whizz to fit as the Mini ones fit straight onto any of the other units. Just remove the Metro/AA/1300GT ones and swop the mounts over from the Mini unit. If they’re split, fit new ones, they’re cheap.

Terminology -
BBU - Big Bore Unit
SBU - Small Bore Unit

NOTE: This information covers transplanting large-bore engine units into small-bore engined Minis. For further information for exact differences between pre-A+ and A+ units, see relevant separate article.

Engine mountings and steady bars.
Engine mountings are a whizz to fit as the Mini ones fit straight onto any of the other units. Just remove the Metro/AA/1300GT ones and swop the mounts over from the Mini unit. If they’re split, fit new ones, they’re cheap. If using the AA/1300GT unit - it's advisable to cut off the 'wings' on the front plate that carried the engine mounts on the radiator end.

Exhausts - Basic information

The sheer volume and diversity of bolt on goodies available for our cherished Minis underlines the fact that a very large portion of them is modified in some way. Be it just dress up items to personalise it aesthetically, or tuning parts to improve performance.

In the latter’s case, either more power or more economy are sought - both being desired by many. Should it also enhance the looks at the same time, so much the better. Unfortunately not many components can achieve this without integrating with a number of others. The exhaust system, however, is one of the few.

Although the exhaust’s efficiency and effectiveness is reliant on a well matched system from the exhaust valve in the cylinder head to the tail pipe, the majority view it as two separate pieces - the exhaust manifold, and the ‘system’. Not entirely mis-placed, as this is how vendors present them - folk buying one or the other, though mostly both, dependent on guidance

Exhausts - Sizing and styles

Now I just know I'm going to make myself very unpopular with an array of people by doing this article, but I can't help myself. It is something that plagues me continually.

It does not seem to matter which way I try and explain it, or how I represent it, I always meet a barrage of either unsubstantiated or uneducated reason and arguments. So now I have the stage to myself, I will put this as I see it from a wealth of experiment and reasoning over the past twenty years or so.

Exhausts. A subject that a great deal is known about in theory, yet a diminutive amount is actually applied in practice as far as the poor little A series engine is concerned. In fact, the only country where I have seen any money/time put into developing exhaust systems (and that means from cylinder head to the tailpipe) for the venerable little motor, is in America. It is a consequence of those that race and seek the ultimate fully expect to have to pay for it.

Induction system - Improvements, initial tasters…

Modern technology has seen dramatic improvements in power outputs over very recent years. Just look at Formula One, where 3000cc engines are now putting out the sort of power not even dreamed of not so long ago at rpm levels that make motorcycle engines flinch!

At the end of every racing season the new/recurrent champions are confirmed, and the rest of the field turning their attention towards next year/season and ways of beating the crowned champ. Invariably this involves that age-old quest for the illusive extra horsepower this year's champion seemed to have over everybody else. So I thought it may be useful to have a look at some stuff that is largely over-looked by many and to further agitate those little grey cells.

Modern technology has seen dramatic improvements in power outputs over very recent years.

Injection Cars - Tuning up-date

OK, so what's happened to the Min Tec/Mini Spares development program?

It has been a long time between my first few words on basic injection car tuning and these - for that I apologise, but business has been unbelievably fraught this year.

I did promise regular and frequent up-dates, but the best laid plans, and all that… As I said, business has been more than brisk.

OK, so what's happened to the Min Tec/Mini Spares development program? Apart from a whole lot of investigation and repetitive research into what's available currently - not that much. It is all hinging on this forthcoming ECU from this particular company. Unfortunately the company concerned is not run by businessman or automotive engineers. They are electronics whiz kids who are trying to achieve the Holy Grail.

Lubrication - Oil pumps

Essential to the well being of every engine is its oil pump and oil. Much in the same way as the heart and blood is deemed relatively important to us humans! It's also another of those greatly misunderstood and, unfortunately, misrepresented subjects connected to engines.

An alarming number of so-called A-series engine specialists would have you believe that once parting with a veritable bundle of your hard earned readies on that mega motor, what you really need to keep it in good health is a high-pressure/high-flow oil pump. Seems a sensible consideration - except in the A-series world it's impossible. Oh, there are pumps that will give better flow rates than others, but high pressure? Absolutely not.

Oil pressure is regulated by the relief valve in the block of an A-series, not in the oil pump as with say a Ford. Yeah, you know - the one that gets jammed, causing heart failure as you believe your crank bearings have dissolved, and is a pig to get out.

Cylinder head 2022

Historical Article - May 1993 - Maximum Side Draught

Maximum Side-Draught Carburettor Potential For many years now, the steel-formed inlet manifolds - produced by a well known steel tube manifold fabrication company in England - have been accepted as THE performance manifolds for side draught carbs. This was mainly due to the extremely poor quality and terrible basic design of the alloy cast manifolds on the market. There were one or two that were deemed on a par with the steel ones - and were supposedly multi-funcitonal to use SU's also - but were more expensive and not particularly readily available.