Rocker gear - General compendium

Whether you’re building a solid road performer or fire-breathing monster, the main goal is to improve air/fuel flow into the engine. The more you can get in, the more power you can get out. Cheapest chunk of power improvement comes from sorting the asthmatic manifolding and exhaust by applying a stage one kit. Then what? Considering the ‘get more in to get more out’ theme, the main restriction - all else being equal - is the valves and their behavior. How big they are, how efficient they are and how long they’re open for determines how much gets in with each gulp each bore/piston makes. Modified cylinder heads are popularly next, although it has to be said that although a well modified cylinder head will improve performance, the gain against cost is nowhere near that given by the ‘stage one’ kit application. A good stage one kit’s improvement verses cost is around £12.50 per 1 hp, a decent modified head typically £30 per 1hp - dependent on application. Hmm.

SU Carbs - HIF, a more finely honed instrument

Modern technology continually sweeps its ever-growing arm across all manufactured products and the SU was no exception. From closer scrutiny, and more demanding emissions control the HIF variant was born. So what have they done to improve it over its predecessor - the HS - and is it worth hanging out for? PROS. Integral float - the 'IF' in the new type number HIF. The previous H and HS type carbs with their side-mounted remote float bowls worked fine until used in racing where serious cornering speeds generated enough G-forces to lean-out the fuel mixture. The remedy was to fit a spacer between the float lid and float bowl to raise the fuel level held in it. OK when running, but at idle and rest, fuel would bubble out of the jet - causing bore washing, poor pick-up, and horrendously rich CO mixtures at idle! Fitting the float integral with the carb, directly below the jet hole (port/orifice), eliminated this problem. Jet temperature compensation - This was first aired on HS types

SU CARBURETTORS - HOW THEY WORK

Basic knowledge Even though the SU carburetter (carb) is a very basic yet precise instrument, some fundamental understanding on just how it works is needed to be able to deal with common problems and tuning. Following is as basic a description of what's going on that I can manage! First you need to be comfortable with the main aim of any carb - to supply the engine with a finely atomized fuel/air mixture in the right strength for all operating conditions. This means from idle to flat out and everything in-between. All carbs achieve this using the same method - a venturi or choke (restriction) is used to speed up the velocity of the in-coming air to create a reduction in pressure. This is used to draw fuel from the float chamber via a suitably sized jet hole into the air stream, and hence into the engine. The perfect carb will supply the engine with optimum mixture for both maximum power throughout the full throttle-angle range (variable restriction - as in butterfly and spindle) a

SU Carbs - The history

Practically every Mini owner can name the brilliant engineer responsible for our obsession. Many can name the man responsible for the rubber suspension spring.

A goodly number know a fair bit about the engine's heritage and the man who came up with the extremely efficient cylinder head design.They account for the biggest chunks of the Mini's anatomy. But what about that other extremely simple yet hugely effective instrument that features so prominently when engine tuning occurs - the SU carburetter? A limited few can tell you what 'SU' stands for, extremely few have any idea of its concept and evolution. So let's put that right… In the beginning Strangely enough, it all started way back with William Banks Skinner; one of the owners/directors of the well-known Lilly and Skinner footwear distributors.

C-STN17 - MINI SPARES STAGE ONE KIT (998cc only)

Beware: Instructions must be read carefully.

Although the 998/1300 stage one kits are bolt on parts easily fitted by any person with mechanical knowledge, the following must be understood.

Historical Article - Nov 1991 - MINI SPARES 1000CC STAGE ONE KIT

Both Keith Calver and Keith Dodd have fitted the Mini Spares kit to their 1000cc cars. Keith Calver was involved in getting the ignitions and needle settings correct at Peter Baldwin’s (Marshalls) rolling road in Cambridge.

Many people already have some of the parts on their car without know how close they are to extra power. The parts required are the original Competition Silencers exhaust RC40, Mini Spares special inlet manifold, Maniflow freeflow exhaust manifold...

Historical Article - Nov 1991 - MINI SPARES 1000CC STAGE ONE KIT

Both Keith Calver and Keith Dodd have fitted the Mini Spares kit to their 1000cc cars. Keith Calver was involved in getting the ignitions and needle settings correct at Peter Baldwin’s (Marshalls) rolling road in Cambridge.

Many people already have some of the parts on their car without know how close they are to extra power. The parts required are the original Competition Silencers exhaust RC40, Mini Spares special inlet manifold, Maniflow freeflow exhaust manifold...

Historical Article - Nov 1992 - Little Red Booster - fastest road legal mini

In the November 1991 issue of Mini Tech News, we found ourselves with a half page to fill, and for no particular reason really, decided to throw a picture of our man Phil Oram’s recently departed Riley Elf racer...

Historical Article - May 1993 - Alternative Engine Tuning

ALTERNATIVE ENGINE TUNING Forthcoming, and indeed existing, emission control regulations are making it more and more difficult for people to run modified engines on the road. Sometime ago, I said that I would be looking at alternative ways to make a more interesting road car to the normal route - bigger everything (pistons, carbs, cams, etc.). I must confess to being a supporter of milder states of tune for road use cars for sometime.

Historical Article - October 1993 - Converting WET to DRY suspension

Converting WET to DRY suspension The following is a practical way of converting your wet suspension to dry, acknowledging the fact that with enough skill, enterprise and facilities...

Historical Article - October 1993 - Calver's Clinic

Calver's Clinic There are many small side issues, problems, technical hints and general advice that do not warrant a full story, but never the less are important enough to cover. To this end I will be using "Calver's Clinic" as a regular feature in Mini T ech News to cover such things.A friend and colleague of Mini Spares runs the "Mincomp Mini " in America. His name is Bill Gilcrease - those of you who have read Mini Tech News 1 may recall that he was in this issue covering his escapades at the USA run-offs in Atlanta

Historical Article-August 1994- 8-Port CCC

8-Port CCC Magazine reprint Mike Askew is the editor of Mini World magazine, and anyone who writes so many nice things about our 8-Port car must surely be a jolly nice chap. His story in Cars and Car Conversions is reproduced,with their kind permission, below.

Historical Article-August 1994- 8-Port CCC

8-Port CCC Magazine reprint Mike Askew is the editor of Mini World magazine, and anyone who writes so many nice things about our 8-Port car must surely be a jolly nice chap. His story in Cars and Car Conversions is reproduced,with their kind permission, below.