Author Topic: Banks Twin Link Rear Suspension  (Read 2639 times)

0 Members and 1 Guest are viewing this topic.

Offline Dilkris

  • Sr. Member
  • ****
  • Joined: Oct 2017
  • Location: Shrewsbury (UK)
  • Posts: 447
Re: Banks Twin Link Rear Suspension
« Reply #30 on: Saturday,June 19, 2021, 01:53:57 AM »
Reason I was interested in comments, my current build is using a Porsche 5 speed.......
Kram350Kram - Out of interest, what engine are you using? 

Offline MRN I J

  • Sr. Member
  • ****
  • Joined: May 2020
  • Location: Knowle, Solihull, West Midlands, UK
  • Posts: 259
    • Four Ashes Garage
Re: Banks Twin Link Rear Suspension
« Reply #31 on: Saturday,June 19, 2021, 03:44:44 AM »
Hi,

New member here.  My name is Neil from Sheffield England. 

Does anybody have any experience with the 'Banks Twin Link Rear Suspension system' which is available from Europa Engineering in England?

I am a retired engineer and instinctively dislike the Chapman fixed length driveshaft arrangement which seems to rely on double roll pins locking the spliced joint between the differential and the driveshafts, thus subjecting the differential and the Hardy Spicer joints to compression and tension forces which they were not really designed to withstand.

Does the Banks system eliminate this and leave the spliced joint to slide slightly with suspension movement as it should.

Any comments welcome, even if they are only to tell me that I have misunderstood the whole thing !

Neil Willatt
Hi Neil
Bit late to the party and my first post on this forum. I have a  Banks twin link on my TC Special fitted to original chassis and rear disc conversion...Its a game changer! One of the issues with the Chapman designed shimmed driveshaft arrangement is that some twisting torque is transmitted to the transaxle and bell housing. On 70's narrow radial tires (and crossplys) there is no issue. However when one puts sticky modern rubber on these cars the lateral forces appear just too much... for shall we say spirited driving. I broke the bell housing on my 5 speed on average twice a year before I decided to go a better route with the Banks Twin link. The other alternative is a Banks chassis with pick ups for rear A frames. My friend at Oselli engineering would weld up the bell housing and return it to me saying see you in a few months Neil! Its been on the car for nearly 20 years now and survived track days etc

Thoroughly recommend it

BTW seems a lot of Europa owners called Neil! My mate in Taunton UK is called Neil and has owned his TC since the late 1970's as have I

Not quite you are correct there, I used Avon A15 slicks on my S2, the 336 gearbox was fitted with a Quaiffe ATB, the rear gearbox mount was changed to a solid one for competition, we sprinted the car very succesfully for 3 full seasons before it looked so tatty (wife hit a muntjac deer one night) we had to look to rebuild the body & I also wanted to make it into a circuit racer.
We used sticky Bridgestone 185/60 x 13 on 6" rims for the road & we drove it seriously quickly most of the time, never had any problems with the gearbox casing
Regards Chris

other cars inc wifes cars
Aston Martin DB MkIII DHC (wifes)
Aston Martin DB2 Saloon (shared)
MkI Austin Cooper S with less than 50k miles on it
Oldest existing LR Discovery S3, one of 1st 125 hand built cars
Peugeot 406 with less than 55k miles on it

Offline GavinT

  • Super Member
  • *******
  • Joined: Oct 2016
  • Location: Queensland, Oz
  • Posts: 1,160
Re: Banks Twin Link Rear Suspension
« Reply #32 on: Saturday,June 19, 2021, 06:23:10 AM »
. . . my current build is using a Porsche 5 speed and I am using the stock design of the Europa suspension and half-shafts with both inner and outer u-joints.

I have no experience with the Porsche gearbox but suspect it's wider than the Renault 3xxx boxes used in the Europa.

If you were to copy the stock Lotus arrangement on to the Porsche box, I expect the half shafts (upper links) would need to be shorter than the Lotus ones assuming the track is to be maintained. This will affect the rear roll centre height which, in turn, will affect the roll axis.
To the extent that's a problem or not might need someone with Chapmanesque suspension design credentials.

In Richard Mann's design, the separate upper link mimics the original half shaft in terms of geometry, length & pivot points etc.

Quote
Question is will the Porsche hubs (with their c- clip design) remain in the case or get dislodged during suspension movement? Any comments appreciated.   

Can't answer re the c-clip design but there's more to consider.
The Europa 3xxx transaxles all use spacers at the inner yoke such that loads from the half shafts are transferred via those substantial diff bearings.
You would need to determine if the Porsche transaxle can accept the loads or be modified similarly.

What engine are you contemplating putting in front of the Porsche box?

BDA, that e-mail address is no longer valid.



« Last Edit: Saturday,June 19, 2021, 06:28:19 AM by GavinT »

Offline BDA

  • Super Member
  • *******
  • Joined: Jul 2012
  • Location: North Carolina
  • Posts: 9,536
Re: Banks Twin Link Rear Suspension
« Reply #33 on: Saturday,June 19, 2021, 06:47:10 AM »
In Richard Mann's design, the separate upper link mimics the original half shaft in terms of geometry, length & pivot points etc.

Thanks for mentioning that. I knew there was something I forgot to say! I believe both Mann's scheme and Richard at Bank's scheme mimic the original Europa geometry.

BDA, that e-mail address is no longer valid.

Bummer! I was afraid of that! I emailed the friend I mentioned who implemented Mann's scheme to see if he has a more recent email address. I post what I find.

Offline Dilkris

  • Sr. Member
  • ****
  • Joined: Oct 2017
  • Location: Shrewsbury (UK)
  • Posts: 447
Re: Banks Twin Link Rear Suspension
« Reply #34 on: Saturday,June 19, 2021, 08:44:07 AM »
Its not mine - but I wish it was.

Offline BDA

  • Super Member
  • *******
  • Joined: Jul 2012
  • Location: North Carolina
  • Posts: 9,536
Re: Banks Twin Link Rear Suspension
« Reply #35 on: Saturday,June 19, 2021, 09:10:51 AM »
Beautiful car! It has it's version of a "twin link", presumably from a 47

Offline GavinT

  • Super Member
  • *******
  • Joined: Oct 2016
  • Location: Queensland, Oz
  • Posts: 1,160
Re: Banks Twin Link Rear Suspension
« Reply #36 on: Saturday,June 19, 2021, 09:57:03 AM »
Bummer! I was afraid of that! I emailed the friend I mentioned who implemented Mann's scheme to see if he has a more recent email address. I post what I find.

Sent you a message so as to foil the web scrapers.  ;)

Offline kram350kram

  • Sr. Member
  • ****
  • Joined: Dec 2019
  • Location: Georgia
  • Posts: 455
Re: Banks Twin Link Rear Suspension
« Reply #37 on: Saturday,June 19, 2021, 06:24:22 PM »
Thanks for all the input. The stock drive shafts have been shorten as the Porsche trans is wider than the stock Europa by 6". I refigured the geometry and it all seems to work; no binding, retains negative camber thru wheel travel, revised adjustable lower links shortened in proportion to the the new drive shaft lengths. According to the local Porsche experts the trans should be able to take any side loads. A few pictures attached. Engine is a 289/302 Ford.

Offline BDA

  • Super Member
  • *******
  • Joined: Jul 2012
  • Location: North Carolina
  • Posts: 9,536
Re: Banks Twin Link Rear Suspension
« Reply #38 on: Saturday,June 19, 2021, 06:28:22 PM »
Interesting Europa you have there, kram350kram! Care to share some details and pictures?

Offline kram350kram

  • Sr. Member
  • ****
  • Joined: Dec 2019
  • Location: Georgia
  • Posts: 455
Re: Banks Twin Link Rear Suspension
« Reply #39 on: Saturday,June 19, 2021, 06:46:12 PM »
Updated engine picture. Wiring near complete. Body off next. A lot of mods to say the least.

Offline BDA

  • Super Member
  • *******
  • Joined: Jul 2012
  • Location: North Carolina
  • Posts: 9,536
Re: Banks Twin Link Rear Suspension
« Reply #40 on: Saturday,June 19, 2021, 07:17:28 PM »
She’ll be a monster when you’re done!

Offline europa88

  • Jr. Member
  • **
  • Joined: Mar 2013
  • Location: Oxfordshire UK
  • Posts: 79
    • Europa88
Re: Banks Twin Link Rear Suspension
« Reply #41 on: Sunday,June 20, 2021, 03:15:08 AM »
Hi,

New member here.  My name is Neil from Sheffield England. 

Does anybody have any experience with the 'Banks Twin Link Rear Suspension system' which is available from Europa Engineering in England?

I am a retired engineer and instinctively dislike the Chapman fixed length driveshaft arrangement which seems to rely on double roll pins locking the spliced joint between the differential and the driveshafts, thus subjecting the differential and the Hardy Spicer joints to compression and tension forces which they were not really designed to withstand.

Does the Banks system eliminate this and leave the spliced joint to slide slightly with suspension movement as it should.

Any comments welcome, even if they are only to tell me that I have misunderstood the whole thing !

Neil Willatt
Hi Neil
Bit late to the party and my first post on this forum. I have a  Banks twin link on my TC Special fitted to original chassis and rear disc conversion...Its a game changer! One of the issues with the Chapman designed shimmed driveshaft arrangement is that some twisting torque is transmitted to the transaxle and bell housing. On 70's narrow radial tires (and crossplys) there is no issue. However when one puts sticky modern rubber on these cars the lateral forces appear just too much... for shall we say spirited driving. I broke the bell housing on my 5 speed on average twice a year before I decided to go a better route with the Banks Twin link. The other alternative is a Banks chassis with pick ups for rear A frames. My friend at Oselli engineering would weld up the bell housing and return it to me saying see you in a few months Neil! Its been on the car for nearly 20 years now and survived track days etc

Thoroughly recommend it

BTW seems a lot of Europa owners called Neil! My mate in Taunton UK is called Neil and has owned his TC since the late 1970's as have I

Not quite you are correct there, I used Avon A15 slicks on my S2, the 336 gearbox was fitted with a Quaiffe ATB, the rear gearbox mount was changed to a solid one for competition, we sprinted the car very succesfully for 3 full seasons before it looked so tatty (wife hit a muntjac deer one night) we had to look to rebuild the body & I also wanted to make it into a circuit racer.
We used sticky Bridgestone 185/60 x 13 on 6" rims for the road & we drove it seriously quickly most of the time, never had any problems with the gearbox casing

Perhaps I had a weak bellhousing from the factory. It cracked around the output shaft seal from the gearbox lots of times. I was using Avons,Yokos and now on Toyo's. Richard Winter had seen a few of these issues on Europa's, I didn't imagine it. Were you using a Twincam or Renault engine, as the bellhousing design is different. BTW it was the bellhousing not the gearbox casing that cracked! Perhaps it only happens on Twinks. My transaxle was a 365 5 speed originally now on a NG1 as I had a lot of issues with the 365.
« Last Edit: Sunday,June 20, 2021, 03:49:56 AM by europa88 »
If you no longer go for a gap that exists, you are no longer a racing driver.

Offline MRN I J

  • Sr. Member
  • ****
  • Joined: May 2020
  • Location: Knowle, Solihull, West Midlands, UK
  • Posts: 259
    • Four Ashes Garage
Re: Banks Twin Link Rear Suspension
« Reply #42 on: Sunday,June 20, 2021, 04:34:54 AM »
Hi,

New member here.  My name is Neil from Sheffield England. 

Does anybody have any experience with the 'Banks Twin Link Rear Suspension system' which is available from Europa Engineering in England?

I am a retired engineer and instinctively dislike the Chapman fixed length driveshaft arrangement which seems to rely on double roll pins locking the spliced joint between the differential and the driveshafts, thus subjecting the differential and the Hardy Spicer joints to compression and tension forces which they were not really designed to withstand.

Does the Banks system eliminate this and leave the spliced joint to slide slightly with suspension movement as it should.

Any comments welcome, even if they are only to tell me that I have misunderstood the whole thing !

Neil Willatt
Hi Neil
Bit late to the party and my first post on this forum. I have a  Banks twin link on my TC Special fitted to original chassis and rear disc conversion...Its a game changer! One of the issues with the Chapman designed shimmed driveshaft arrangement is that some twisting torque is transmitted to the transaxle and bell housing. On 70's narrow radial tires (and crossplys) there is no issue. However when one puts sticky modern rubber on these cars the lateral forces appear just too much... for shall we say spirited driving. I broke the bell housing on my 5 speed on average twice a year before I decided to go a better route with the Banks Twin link. The other alternative is a Banks chassis with pick ups for rear A frames. My friend at Oselli engineering would weld up the bell housing and return it to me saying see you in a few months Neil! Its been on the car for nearly 20 years now and survived track days etc

Thoroughly recommend it

BTW seems a lot of Europa owners called Neil! My mate in Taunton UK is called Neil and has owned his TC since the late 1970's as have I

Not quite you are correct there, I used Avon A15 slicks on my S2, the 336 gearbox was fitted with a Quaiffe ATB, the rear gearbox mount was changed to a solid one for competition, we sprinted the car very succesfully for 3 full seasons before it looked so tatty (wife hit a muntjac deer one night) we had to look to rebuild the body & I also wanted to make it into a circuit racer.
We used sticky Bridgestone 185/60 x 13 on 6" rims for the road & we drove it seriously quickly most of the time, never had any problems with the gearbox casing

Perhaps I had a weak bellhousing from the factory. It cracked around the output shaft seal from the gearbox lots of times. I was using Avons,Yokos and now on Toyo's. Richard Winter had seen a few of these issues on Europa's, I didn't imagine it. Were you using a Twincam or Renault engine, as the bellhousing design is different. BTW it was the bellhousing not the gearbox casing that cracked! Perhaps it only happens on Twinks. My transaxle was a 365 5 speed originally now on a NG1 as I had a lot of issues with the 365.

Renault crossflow with 150bhp
Regards Chris

other cars inc wifes cars
Aston Martin DB MkIII DHC (wifes)
Aston Martin DB2 Saloon (shared)
MkI Austin Cooper S with less than 50k miles on it
Oldest existing LR Discovery S3, one of 1st 125 hand built cars
Peugeot 406 with less than 55k miles on it

Offline jbcollier

  • Super Member
  • *******
  • Joined: Nov 2013
  • Location: Edmonton, Alberta, Canada
  • Posts: 5,823
Re: Banks Twin Link Rear Suspension
« Reply #43 on: Sunday,June 20, 2021, 05:57:23 AM »
I would check carefully and not take one mechanic’s word on whether the output shafts can be load bearing.  I can’t think of a reason why Porsche would design it to be load bearing.  The Renault 336 and 365 boxes were not load bearing either.  Lotus designed the inner halfshaft yoke to be load bearing with the special spacer — also why the boxes actually don’t leak much at all in the Renault application.   Your mechanic may turn out to be correct but a “strong” transaxle doesn’t mean it’s also capable of taking suspension loads on its output shafts.

Offline europa88

  • Jr. Member
  • **
  • Joined: Mar 2013
  • Location: Oxfordshire UK
  • Posts: 79
    • Europa88
Re: Banks Twin Link Rear Suspension
« Reply #44 on: Sunday,June 20, 2021, 06:38:00 AM »
Hi,

New member here.  My name is Neil from Sheffield England. 

Does anybody have any experience with the 'Banks Twin Link Rear Suspension system' which is available from Europa Engineering in England?

I am a retired engineer and instinctively dislike the Chapman fixed length driveshaft arrangement which seems to rely on double roll pins locking the spliced joint between the differential and the driveshafts, thus subjecting the differential and the Hardy Spicer joints to compression and tension forces which they were not really designed to withstand.

Does the Banks system eliminate this and leave the spliced joint to slide slightly with suspension movement as it should.

Any comments welcome, even if they are only to tell me that I have misunderstood the whole thing !

Neil Willatt
Hi Neil
Bit late to the party and my first post on this forum. I have a  Banks twin link on my TC Special fitted to original chassis and rear disc conversion...Its a game changer! One of the issues with the Chapman designed shimmed driveshaft arrangement is that some twisting torque is transmitted to the transaxle and bell housing. On 70's narrow radial tires (and crossplys) there is no issue. However when one puts sticky modern rubber on these cars the lateral forces appear just too much... for shall we say spirited driving. I broke the bell housing on my 5 speed on average twice a year before I decided to go a better route with the Banks Twin link. The other alternative is a Banks chassis with pick ups for rear A frames. My friend at Oselli engineering would weld up the bell housing and return it to me saying see you in a few months Neil! Its been on the car for nearly 20 years now and survived track days etc

Thoroughly recommend it

BTW seems a lot of Europa owners called Neil! My mate in Taunton UK is called Neil and has owned his TC since the late 1970's as have I

Not quite you are correct there, I used Avon A15 slicks on my S2, the 336 gearbox was fitted with a Quaiffe ATB, the rear gearbox mount was changed to a solid one for competition, we sprinted the car very succesfully for 3 full seasons before it looked so tatty (wife hit a muntjac deer one night) we had to look to rebuild the body & I also wanted to make it into a circuit racer.
We used sticky Bridgestone 185/60 x 13 on 6" rims for the road & we drove it seriously quickly most of the time, never had any problems with the gearbox casing

Perhaps I had a weak bellhousing from the factory. It cracked around the output shaft seal from the gearbox lots of times. I was using Avons,Yokos and now on Toyo's. Richard Winter had seen a few of these issues on Europa's, I didn't imagine it. Were you using a Twincam or Renault engine, as the bellhousing design is different. BTW it was the bellhousing not the gearbox casing that cracked! Perhaps it only happens on Twinks. My transaxle was a 365 5 speed originally now on a NG1 as I had a lot of issues with the 365.

Renault crossflow with 150bhp

Ahh that makes more sense to me. My Twink too is about 150HP!
If you no longer go for a gap that exists, you are no longer a racing driver.