Project Letty – AMF 1.4TDI Weight reduction, balance improvement/simplification.

Have you considered BMW i3 wheels?

Those weigh more at 7,5kg but perhaps the slim formfactor should improve mpg.

Drawback is bolt pattern and odd 19 inch rubber, but the bigger offset should allow for adapters to get it legal.

Otherwise a costfree fix it is run with absolute minimum level of liquids, fuel, water, oil, washerfluid but presume you do that already.

Wonder what would happen if you put a titanium/aluminium shape of 1 liter in the bottom oil pan to displace 1 liter of oil reducing the total amount from 4,2ish to 3,2ish. Alternatively a custom bottom oil pan.

What about to remove the antiroll bar? Inner wheel plastic housings? Brake shields?
 
Hi, more from me.

Suspension strut top mounts. These look like they are fairly heavy but basic lumps of steel and rubber. You could machine some nice billet ally/titanioum ones and poly bush them perhaps (also to improve geo stability) I changed my cam belt recently and the actual engine mounts on the right are light alloy, but top mounts look steel.

More contentious would be to remove the abs and even the servo. My Elise at 750kg came with neither of those from the factory and doesnt feel heavy in the brakes at all so a light A2 might be able to get away with it, lots of engineering and setup though and may not be legal where you are.

Door cards and pockets.
Not sure if you can remove the pockets from the cards but that might be straight forward, same re the handle and go for a strap. You could replace the entire door card with a custom one. This is only marginal, but its all stuff that can add up.
Oh and maybe the servo from the rear door and just use manual release (if you can bothe with the hassle, maybe rig a hidden external pull)

Two things to add in (apologies if already considered)
FIA master key for battery isolation. If your doing lots of fiddling its better IMO have a switch to disconnect the battery than constant unbolt/rebollt. I damaged the threads/nearly lost a race session on my race battery doing that as they wernt tight. Switch is more reliable and safer.

Fire extinguisher (a decent size). You may already have factored that in race ones are lighter than normal car but can cost lots more. Im not saying plumbed in as thats race specific.
 
Probably a bit OT, due to cost, but has anyone fitted a Wilwood radial caliper setup to an A2? It should reduce unsprung weight, reduce drag (as the caliper is fixed and not sliding) and improve braking performance. I can't find any mention of it on this site and would probably never be worth the time, effort and money, but it would be interesting to see!
 
Hi @gills,
Sorry, I have no experience with the Wilwood sets. I cannot find that they deliver any set that will fit A2. All mine A2s have casted anti rotation device and I believe it is demanding to get these sets to fit. 4 or 6 piston calipers are of cause giving great braking performance. 700£ is a lot to my opinion.
They should be half the weight of standard A2s to be worth the money, unless I would think twice....

Cheers
dieselfan
 
Have you considered BMW i3 wheels?
Those weigh more at 7,5kg but perhaps the slim formfactor should improve mpg.
Drawback is bolt pattern and odd 19 inch rubber, but the bigger offset should allow for adapters to get it legal.
Otherwise a costfree fix it is run with absolute minimum level of liquids, fuel, water, oil, washerfluid but presume you do that already.
Wonder what would happen if you put a titanium/aluminium shape of 1 liter in the bottom oil pan to displace 1 liter of oil reducing the total amount from 4,2ish to 3,2ish. Alternatively a custom bottom oil pan.
What about to remove the antiroll bar? Inner wheel plastic housings? Brake shields?
Hi @Olerype
I3 rims/wheels must be lighter than 15x6" A3 pepperpots to be in question for the moment. I'm very keen to run on 185/60 R15 until I find any that runs better. I am very pleased with that dimension. With a 100kg lighter car I hope to be even more happy.
Washerfluid bag is already moved back to the battery location.
Oil volume: agree that it is strange for a 1.4 engine to have same oil volume as 4 L engine...
To reduce the oil volume would bring the engine much faster up to operational temperature and the engine will pollute less, and thats good too... I already have an extra oil tray and it is not much hazzle to modify it.... Very good idea, Ole ? If I decide to build a summer car I will go for it-
I will make new brake shields of carbon/epoxy, to have them without any corrosion will be just fantastic, brilliant Ole.

Cheers
dieselfan
 
Hi, more from me.
Suspension strut top mounts. These look like they are fairly heavy but basic lumps of steel and rubber. You could machine some nice billet ally/titanioum ones and poly bush them perhaps (also to improve geo stability) I changed my cam belt recently and the actual engine mounts on the right are light alloy, but top mounts look steel.

Two things to add in (apologies if already considered)
FIA master key for battery isolation. If your doing lots of fiddling its better IMO have a switch to disconnect the battery than constant unbolt/rebollt. I damaged the threads/nearly lost a race session on my race battery doing that as they wernt tight. Switch is more reliable and safer.
Brilliant @carbore ?
Suspension strut top mounts are added to the modification list, Super ?
Same for the FIA master key for battery isolation.
The other proposals are also noted, though I must focus on those that I am capable to perform my selves.....

Cheers
dieselfan
 
A2 Team ?

Must say I'm overwhelmed by all the high quality postings and the detail level all of you have shared. ?
I have tried to give all of you a decent replay but when I read trough I see that there are several I have missed, sorry for that.

Some of the ideas advised are so good that I will re-consider some of the basis I had planned.
There are several parts that will be re-designed to become much lighter parts and a majority will luckily affect the unsprung front axle weight , that is so important to me since it is so essential to obtain the handling I am after....

Several of these parts will have to be re-engineered and some parts will probably undergo destructive testing in addition to non destructive testing before I will be happy to use them.
Some of the proposals are of a kind that I will need authority approval here in Norway to have the solution road legal.
That will take time.
Machining and to source materials in the grade I want to have will also take time.
My regular job is gone but I still need food on the table so that will take time too...
So when you will notice slow progress on an idea you gave me please do not take it as I'm not grateful for what you did for the Project ?

Cheers
dieselfan
 



These are just some of the parts we do for the MCC smarts.

I am working on a carbon fibre bonnet as we speak. Also want to do the rear tailgate in carbonfibre with a poly glass instead
 
Looking into the values in some of the A2's registration papers make me dizzy.....
All these cars are registered in Norway, based on German TuV approval.
I need tables to think clearly, please bear with me....

Look at the huge contradictory values for Load index vs Max weight and max weight on one axle, are these typos or is it the same in UK and other countrys ??
Same for top speed. One AMF rated to 180 km/h and the other one 190.... Both are non OSS so no weight difference.
I am asking first of all because I need arguments for the discussions with my authorities. Hopefully the table below will appear OK on both pc and potables, if not please tell me and I will try pdf
Prod​
Model​
Eng code​
Top speed​
Weight​
Weight +driver​
Pay load​
Max weight​
Front axle​
Rear axle​
Roof​
Trailer​
Load index​
Speed index​
ET​
Tire size​
Front width​
Rear width​
Rim​
2002​
1.2TDI 61​
ANF​
168​
855​
930​
315​
1245​
710​
560​
40​
0​
72-710​
R​
38​
145/80 R14​
1463​
1419​
4.5J​
2005​
1.4TDI 75​
BHC​
173​
1020​
1095​
440​
1535​
820​
780​
0​
1000​
77-824​
S​
28​
165/65 R15​
1474​
1439​
5J​
2003​
1.4TDI 75​
AMF​
180​
1020​
1095​
440​
1535​
820​
780​
0​
1000​
77-824​
S​
xx​
165/65 R15​
x​
x​
x​
2001​
1.4TDI 75​
AMF​
190​
990​
1065​
440​
1505​
805
770
0​
0​
81-924​
T​
xx​
165/65 R15​
x​
x​
5.5J​
2005​
1.4TDI 90​
ATL​
188​
1030​
1105​
440​
1545​
820​
780​
0​
1000​
77-824​
T​
34​
175/60 R15​
1474​
1439​
5.5J​
2001​
1.4 75​
AUA​
180​
895​
970​
440​
1410​
745​
740​
0​
0​
74-750​
S​
xx​
165/65 R15​
x​
x​
x​
2003​
1.4 110​
BAD​
202​
995​
1070​
455​
1525​
820​
780​
40​
1000​
77-824​
H​
34​
175/60 R15​
1474​
1439​
5.5J​
2004​
1.4 75​
BBY​
173​
920​
995​
440​
1435​
750​
780​
40​
1000​
76​
S​
28​
165/65 R15​
1474​
1439​
5J​
 
Looking into the values in some of the A2's registration papers make me dizzy.....
All these cars are registered in Norway, based on German TuV approval.
I need tables to think clearly, please bear with me....

Look at the huge contradictory values for Load index vs Max weight and max weight on one axle, are these typos or is it the same in UK and other countrys ??
Same for top speed. One AMF rated to 180 km/h and the other one 190.... Both are non OSS so no weight difference.
I am asking first of all because I need arguments for the discussions with my authorities. Hopefully the table below will appear OK on both pc and potables, if not please tell me and I will try pdf
Prod​
Model​
Eng code​
Top speed​
Weight​
Weight +driver​
Pay load​
Max weight​
Front axle​
Rear axle​
Roof​
Trailer​
Load index​
Speed index​
ET​
Tire size​
Front width​
Rear width​
Rim​
2002​
1.2TDI 61​
ANF​
168​
855​
930​
315​
1245​
710​
560​
40​
0​
72-710​
R​
38​
145/80 R14​
1463​
1419​
4.5J​
2005​
1.4TDI 75​
BHC​
173​
1020​
1095​
440​
1535​
820​
780​
0​
1000​
77-824​
S​
28​
165/65 R15​
1474​
1439​
5J​
2003​
1.4TDI 75​
AMF​
180​
1020​
1095​
440​
1535​
820​
780​
0​
1000​
77-824​
S​
xx​
165/65 R15​
x​
x​
x​
2001​
1.4TDI 75​
AMF​
190​
990​
1065​
440​
1505​
805
770
0​
0​
81-924​
T​
xx​
165/65 R15​
x​
x​
5.5J​
2005​
1.4TDI 90​
ATL​
188​
1030​
1105​
440​
1545​
820​
780​
0​
1000​
77-824​
T​
34​
175/60 R15​
1474​
1439​
5.5J​
2001​
1.4 75​
AUA​
180​
895​
970​
440​
1410​
745​
740​
0​
0​
74-750​
S​
xx​
165/65 R15​
x​
x​
x​
2003​
1.4 110​
BAD​
202​
995​
1070​
455​
1525​
820​
780​
40​
1000​
77-824​
H​
34​
175/60 R15​
1474​
1439​
5.5J​
2004​
1.4 75​
BBY​
173​
920​
995​
440​
1435​
750​
780​
40​
1000​
76​
S​
28​
165/65 R15​
1474​
1439​
5J​

Here's a member @<tuffty/> that had the opportunity to put his A2 TDI on some Axle/4 point scales. Don't know if it's an addition to your question, but it is at least a visual reference.

Post #104,


Cheers.
 
Your CoC will spec these things for your specific car.

Helli has also had his car on the scales, and I think there are a couple of others that have been done over on the German site, but I can't remember.
The UK doesn't "do" specifics like this for the load index and tyre sizes; as a fundamental, it's "not interesting".

For comparison purposes, I'd use an 84 load index (it appears to be eminently available) which is 500kg each and therefore nicely over your load limits. 72-710 is load index 72, 710kg (355x2).

Does this make sense?
 
Your CoC will spec these things for your specific car.

Helli has also had his car on the scales, and I think there are a couple of others that have been done over on the German site, but I can't remember.
The UK doesn't "do" specifics like this for the load index and tyre sizes; as a fundamental, it's "not interesting".

For comparison purposes, I'd use an 84 load index (it appears to be eminently available) which is 500kg each and therefore nicely over your load limits. 72-710 is load index 72, 710kg (355x2).

Does this make sense?
Brilliant Bret ?
In Norway, road authorities punch registration data into a Registration Certificate, which is electronically stored in a national digital register and everyone can search in this database and get access to everything, except for odometer status and name of owner, unless you log in with social security number.
Over here, I will loose my reg plates if I should be caught with too low load index, ET more than +/-12mm,
I have checked around 40 ish A2 AMF and I am surprised there are so many different numbers used, it looks like typos cut/paste issues to me.....
All values in the table are directly cut and paste from the govern database except that I have filled in Kg value together with load index.

Cheers
dieselfan
 
Here's a member @<tuffty/> that had the opportunity to put his A2 TDI on some Axle/4 point scales. Don't know if it's an addition to your question, but it is at least a visual reference.

Post #104,


Cheers.
Brilliant @Menno ?
It's like you read my mind... I have contacted @tuffy for details.
Cheers
dieselfan
 
A small table is made to try to make a better overview , will try to keep it updated as I progress weighing and engineering.

1609430200124.png

Cheers and All the Best for the New Year ?

dieselfan
 
As you completely removed reason for front service hatch, you can make it from carbon fibre (CF). Also you can make complete intake out of CF and maybe relocate it from it's original position more to the back and make some inlet from the new CF front service hatch - grill. Also made all of the cable and holders from CF as well or at least drill some material to get rid of some weight.

Good point is the ABS pump removal. Downside is that you will have to instal brake pressure valve to balance correct F/R brake ratio. But I don't know about deleting it - if it will have an affect on Norwegian MOT...
 
As you completely removed reason for front service hatch, you can make it from carbon fibre (CF). Also you can make complete intake out of CF and maybe relocate it from it's original position more to the back and make some inlet from the new CF front service hatch - grill. Also made all of the cable and holders from CF as well or at least drill some material to get rid of some weight.
Brilliant, @BigBang. if it wasn't for all the hours needed to make a mold... I would have started yesterday to make a complete new flip-front with an integrated Votex shape.

Good point is the ABS pump removal. Downside is that you will have to instal brake pressure valve to balance correct F/R brake ratio. But I don't know about deleting it - if it will have an affect on Norwegian MOT...
My experience with a F/R brake balance valve is very good and I wish I could have it and be able to adjust rear brakes to suite different grip. Though, as you indicate... I will not pass MOT over here with such a modification. I will also loose the speedo signal.
Cheers
dieselfan
 
Simple one, may depend on local regulations but Steering wheel replace/de airbag. Not sure how heavy the A2 one is but a nice little Momo/Sparco one would save a little bit and look quite cool.
 
At this rate, the car will be around half the original weight - you'll then only need half a spring at each corner. Another weight saving ! ??

I'll get my coat :oops:
 
Do any of you know the weight on any of these tires ? (the 3 "Hot"ones are the hottest candidates for the moment.
These are picked based on lowest load index, lowest speed rating and then hopefully.... low weight ?

If there is some serious bad experience with any of them please let me know.

Brand and model
Tire dimension
Load index
Speed rating
Weight
NOK
Continental ContiEcoContact 5 Hot
175/65 R15​
86​
T​
675​
Winrun Tires R330 Hot
185/55 R15​
82​
V​
507​
Sailun Atrezzo Elite
185/55 R15​
82​
H​
500​
Powertrac City Tour
185/55 R15​
82​
H​
587​
Maxxis ME3
185/55 R15​
82​
H​
604​
Nexen N Blue HD Plus
185/55 R15​
82​
H​
625​
Kumho Ecowing ES01 KH27
185/55 R15​
82​
H​
671​
Nankang Econex NA-1 Hot
185/60 R 15​
84​
T​
507​
Achilles 122
185/60 R 15​
84​
H​
371​
Landsail LS388
185/60 R 15​
84​
H​
599​
 
Back
Top