steering angle question for the masses

just a quick question as to what sort of front wheel angle is the norm on full lock for a 40, as i was looking at the chassis this arvo with a wheel roughly in the right spot, and it certainly wont do a u turn in a one way street.

kaspa
 
That would explain the U turn technique in the YouTube video "GT40 spinout".

Coincidentally, the nicest sounding GT40 I have heard. I hope mine sounds half as good.

Cheers,

Lance
 
John, we sort of got into this with Ross Nichol's car- RF- several years ago, he was having issues with race slicks catching wheel arch etc. bottom line you need to choose an upright that will allow you to use minimum scrub radius and a lower w/bone that will allow a decent steering lock, one production upright I have stumbled across a couple of years ago is the front upright from JZ80? Supra along with its lower w/bone which is compatible with GT40 type shock spring attachment, heavy though.
 
Hi Jac i mocked it up using the Mustang11 drop spindle combo i have, and at best i think i could get 23 deg steering angle , is that acceptable,

kaspa
PS how is ole Russ havnt spoken to him for a few years now.
 
Hi Jac i mocked it up using the Mustang11 drop spindle combo i have, and at best i think i could get 23 deg steering angle , is that acceptable,

kaspa
PS how is ole Russ havnt spoken to him for a few years now.

Assuming that is the inner wheel during the turn John a quick sketch gave me about 40/45 ft turning circle, need a bit of throttle assistance to tighten that up!

Have not heard from or seen Mr Noble for some time now, not surprising since I don't get around the tracks much these days.
 
well with a change of tyre down to a 225-60-15 [from a 245] and a bit of fiddling i can now get 28-29 deg max angle on the inside wheel turn in, is this an acceptable figure for these cars, as i cant find one iota of information out there.

cheers Kaspa
 
John
Not sure how much you want to fabricate or adapt but I have found that the MX5 upright appears to give heaps of lock. I can measure it if that helps. Brakes could then be the normal Willwood adaptions. I managed to get the whole upright including the bottom bearing and at this stage am happy.
 

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Russel its not the uprite that has been the problem, its the chassis design and the taper on the side rails, that limit how far the wheel can turn in.

kaspa
 
37' turning circle, 2.8 turns lock to lock for orinal Mk1, as you mention the taper on space frame chassis may hinder you somewhat, the original mono's are relieved in that area.
 
Hi John,
I have 30dgree angle on my set up and that is with a 23-10.5-15 tyre on a 12" wheel with 8"/4" off set so not too bad on the scrub. To be fare I don't have inner wheel arches to deal with, I think it was Jacmac that said if you get a wheel with a deep off set that will help but you have the issue then of it hitting the tie rod or the rear of the bottom A arm be cause the inside edge of the wheel swings quite a bit.

Cheers Leon
 
the MX5 uprights/knuckle that Russell Keach is using also have the axle offset forwards of the kingpin axis to reduce the mechanical trail its only about 10mm to 15mm, not much. This results in slightly less swing in the rear edge of the tyre, more in the front. hard to explain, but does add up.

Russell, it looks like you have had yours apart to repaint? any chance you would be able to confirm if the bearing size is a common size? I wonder if it would be feasible to put a 5 x 4.5" (or 4.75") pcd hub on the stub axle.

Ryan
 
Jac
You never cease to amaze me with you depth of knowledge....we need to clone you.
I have as an option a Chev distributor with the small ignition module on the side that I am going to shorten and fit into the Rover, will that perform comparable to the small MSD box on the standard Rover distributor ? (have spent the money on a TIG machine)
Ryan, just had a look and doubt that there is enough dia as the 100 pcd leaves little material left. Turning up new bearing carrier / hubs is no biggie and could be taylored to what ever dimensions you wanted...i did that on my first car to correct scrub radius.
I can also see what you mean by that off set...never noticed it.
I have attached some pics from my first McLaren replica that may help.
Cheers
Russell
 

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Ive got a couple of S4 stubs n hubs here, can measure those for you guys to compare.
Russell, if you can make a Chev Dizzy fit ( don't see why it would not- you have lathe!) then you open the door to many options, if your using a magnetic pickup then the only concerns are shaft wear and a decent size cap dia to avoid possible crossfire from stronger spark.
 
John, we sort of got into this with Ross Nichol's car- RF- several years ago, he was having issues with race slicks catching wheel arch etc. bottom line you need to choose an upright that will allow you to use minimum scrub radius and a lower w/bone that will allow a decent steering lock, one production upright I have stumbled across a couple of years ago is the front upright from JZ80? Supra along with its lower w/bone which is compatible with GT40 type shock spring attachment, heavy though.

My RF has 60mm scrub radius, RF1 are about 120mm from memory.
I made the arms and the upright
I would consider it to have a normal turning circle.
And my tires dont hit on panels.

So yes as Jac has said you need to reduce the SR.
 
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