MKIV AKL for sale

[302EFI]

Does anybody know which significance the 'AKL' (rather than 'AK') prefix of the chassis number has for a MkIV to qualify as a Lightweight? The background of my question is as follows: Originally I thought AKL = Lightweight, AK = standard MkIV. I recently found out that in the Club's MkIV register some 80 cars are listed as AKLs, while all other sources which I am aware of indicate that only 40 to 50 Lightweights were produced (see, e.g., Alan Faulkner-Stevens' article on Lightweights in the July 2012 issue of ACtion).

[Flyinghorse]

The name lightweight conjures up an image of a vehicle that weights less than a standard car of the model (in this case a mkiv)
   
   Was the lightweight actually lighter ,or was it just styled & engined  differently?
   
   Does anyone have the kerb weight of a "lightweight" mkiv & a standard mkiv?
   
   Graham

[B.P.Bird]

And how much lighter was a CRS?

[Flyinghorse]

Barrie,
   As a starting point a  CRS is 1120kg  kerb weight in standard form from the chassis instruction book.
   The October 19th 2000 press release technical sheet states 1050kg kerb weight.
   
   Graham

[French Frie]

I already started a thread about AK/AKL weight difference here : http://www.acownersclub.co.uk/forum/topic.asp?TOPIC_ID=2346
   But to answer to your question, tech data sheet gives 2250lbs for the MKIV, and it was said that the AKL was 200lbs lighter ... But I'm looking for the detail, and may think that  there may be some marketing magic there !

[B.P.Bird]

Nothing but a weighbridge really means a great deal...

[Flyinghorse]

I suspect that lightening an already light car is a difficult job. The 80/20 rule probabaly applies here.
   
   If a lightweight lost 200lbs is that a good job without resorting to throwing way everything not needed?
   
   Were there any changes to the unsprung weight?
   A look at a lightweight marketing brochure may clear things up if such a thing exists.
   Your thoughts FF were along the same lines as mine,being  part marketing exercise,but I dont know how much more weight could have been lost eaisly with out detracting from the overall package.
   Graham

[SJ351]

The genuine '26' Lightweight is very similar indeed to the standard Mk1V under the skin.
   The weight saved will mainly be as follows :
   No heater or plumbing
   No door safety bars or door cards
   Lighter VW steering column and switch gear
   Lighter dash assembly
   No seat head rests
   Ally heads
   Lighter different rear chassis tubing design and boot floor arrangement
   
   However, the roll over bar will cancel out some of the saved weight above.

[B.P.Bird]

To get any sense from this we need real weights: Sales brochures and technical specifications do not mean much. The Alan Turner chassis and coupé body of A98 weighed 2,482 lbs. at scrutineering in 1964. When rebuilt the  weight was 2,365 lbs ready to go, but with zero fuel. The scrutineering in 1964 probably included a spares and tools package which would have been included in the race specification.
   Has anyone actually weighed a CSL, AK or AKL Mk. IV ? Worth a run to the weighbridge to sort this out for once and for all.
   Any weight has to be defined as to the state of the vehicle weighed. Petrol, oil and lubricants, spare wheel, tools and any additional equipment and so forth. The problem with brochure weights is that there is rarely any specification issued for the time of weighing.

[TLegate]

A little light research within the pages of 'Cobra - The Real Thing' reveals that some kind, thoughtful author (ahem) reproduced the factory specification sheet for the 1992 production 'AC-Autokraft Lightweight' and the figure is: 2520 lb! Page 250 since you ask.

[DWR46]

AK1137 is a US Spec Mark IV with the folowing modifications that would effect the weight. Ford Racing Aluminum cylinder heads, Weber Carburetors, European Exhaust headers and system, Complete with spare tire, tools, jack and all fluids except NO fuel, the car weighs 2,480 lbs on our race scales.

[Alan Faulkner-Stevens]

Based upon my experience of the Lightweight, which is always improving as i see and inspect more cars, there does not appear to be a definitive specification. There is a basic spec. vehicle, from which a original owner may wish to have their car built, much of which is discussed in earlier posts, however dependent upon where the car was to be sold the car when new, it would have to be a minimum Certified Specification, for that Country. This is the problem, if you look at the manufacturing date of the cars they often do not meet the Certification criteria. I know of early UK Lightweights, being sold as a Kit of Parts, to get around UK certification requirements. Engines and lighting fittings do not meet the required laws, not always but often. Later cars, sold into different Countries have many Lightweight features, but carry an EFI engine to meet a that Countries emission requirements.
   Seat head-rests may have been fitted, and things such as hazard flashers all may have been required by Law to allow a new car to be sold in that Country.
   So, based upon my experience there are alot more than 26 cars, for some people these later produced cars may not be true Lightweights, i disagree. They are Lightweight variants, based upon a basic Factory build specification.

[302EFI]

Alan: Is an 'AKL' chassis no. (rather than an 'AK' one) denotative of a Lightweight as per your definition? I am somewhat confused about the large number of AKL designated cars (some 80) in the MkIV register.
   Best wishes,
   Jürgen

[SJ351]

Given the increasing values of the genuine '26' Lightweight cars and the fact that this is likely to be an ongoing trend for the future, perhaps it may one day be a case of 'MK1V Lightweight - which are the orignal's?'. Rod Leach has for many years regularly advertised Ligtweights as being 'one of only c.26 cars made' and, Trevor Legate has effectively confirmed this as being the case i.e. limited numbers/very tight specification to qualify. Therefore, it does seem strange that the Register shows around 3 times this '26' on its books. These gentlemen I would have thought are very reliable sources of both the original factory description and historical output.
   Whilst I am sure that we all admire the 'Lightweight looking' AC Mk1V's and that Brian Aglis would build you whatever you wanted if you were prepared to place your deposit, the Lightweight itself was a very limited edition car with perhaps some 'lesser spotted' factory brethren. I am sure that whilst we would not wish to decry or de-value anyone's machine in any way whatsoever, the facts should really not be distorted going forward by we guardians and custodians of later AC history.

[Alan Faulkner-Stevens]

Because of the hype around "Lightweight" cars, i think the interest about the definitive numbers will continue. All i can say in addition to what i have already stated is this, the cars i have shown in the on-line list the information comes from three places. Firstly, the copy of the AC Build book the Club holds, secondly, notations against a chassis number made my previous Registrars and thirdly, from the photographic records of the cars the Registry is slowly building.
   Again i state, the Lightweight, is a MkIV variant, a version based upon a basic format and which varied dependent upon the Country it was being sold into.
   The standard MkIV long-nose is the car from which a Lightweight is derived, it is also mostly certified and legal for sale in the Countries where it was built for. It is the Lightweights early shape and lesser specification that seems to appeal, however the early CRS models have the same bodyshape as a Lightweight, as the body of one was used for the buck when the Carbon was laid up.
   However, things are never clear with the Cobra, as there are three variants of the CRS body shape, all subtle in difference but different never the less. To add another oddity into the mix, perhaps we could discuss all the early build CRS cars, year 1999/2000 manufacture, having 302 engines produced in 1994.
   It still comes down to this, a low volume car manufacturer would sell what ever the customer wanted, as he had the ability to change the cars to meet any requirement/request, body-shape, colour, engine, trim.
   For this reason alone, until the Club has photographs and details of every MkIV built, things will change.