Jump to content

Design Advice


richardm6994

Recommended Posts

I think I know the answer to this, but Im going to put the question to RHOCaR massive as you guys always come up trumps.

 

So on the lotus 23, the when the centreline of the gearbox drive shaft flanges is lined up with the centere line of the rear hubs, the gearbox is about 2or3 inches too long to fit under the rear fibreglass tub.

 

So Im pounding on this question;

Can I push the gearbox forward a couple of inches? The driveshafts wouldnt line up with the hubs by about 2inch when viewed from above, but does this matter and would the cv joints would take these additional angles on top of the suspension movement?

 

I could then modify the rear gear linkage to give myself another inch and it would then all fit under the rear fibreglass tub?

 

If I cant do this, then the only other thing is to cut and lengthen the tub by a couple of inches which isnt ideal, but doable.

 

Here are some photos and a rubbish sketch;

 

659_F66_B3-7191-44_AA-91_F4-27_B6_C09_D0

 

83139_C3_E-88_B9-49_C5-8509-60_A2_A9_D23

 

A8_D47_A74-3319-4581-9_C5_F-_AB04_C3_FA6

 

E8_D86_FA8-2112-4006-_BF0_A-_D4_FF23_F5_

Link to comment
Share on other sites

I think it should work if you move the box forward as the driveshaft angle would still be quite low and there should still be enough vertical angle for suspension movement. Do you have any specs for the driveshaft maximum running angle?

Rob

Link to comment
Share on other sites

Hopefully someone can correct me if I’m thinking about this all wrong.

 

The half shaft will have 2 cv joints and the angles of both will be equal as the ends of the half shaft need to be parallel.

 

The inner CV will be the plunging type to allow the shaft to grow / shrink with suspension travel.

 

The outer cv will be a fixed type.

 

The outer fixes type cv can operate through 47degrees, which I assume is needed on fwd cars for steering.

 

The inner plunge type cv operates through 26 degrees - presumably because it only has the suspension travel to deal with.

 

As such, my angular limit is the inner CV joint with 26degrees movement. I’ve used 10degrees (horz) by pushing the gearbox froward, so I’ve got to work out what up/down angular movement will be left and make sure it’s enough for the suspension travel.

 

I’ll be doing some more accurate measuring tomorrow but I think it will be fine.

  • Like 1
Link to comment
Share on other sites

Vector diagram of all movements & shaft lengths ?? The distance between the centres of rotation of the CV joints may be very close & so use up your "spare16* " quickly.

 

If the distance between CV joint centres is around 285 mm & inner CV is already 10* off neutral point --- 75 mm of suspension travel up & down from neutral should give a mis-alignment of the joint of 18*.

 

Probably all wrong & I need to go back to school!!

Edited by florin metal works
Link to comment
Share on other sites

Guest lotusPaul

Can you put key dimensions onto a suspension computer, ie pins n strings on a garage wall?

 

You can then plot all the main angles of bump rebound. This will give you all the angles you need. It will also show you the camber changes as you raise and lower too. Around 2°

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...