1966 Barracuda. Converting to RHD

Bozwell · Post by **Bozwell** » Thu Jul 23, 15 11:33 pm

I know its the wrong car and the Barracuda has been neglected, it'll just have to wait.

also bought this for the engine and gearbox for the S800

'nuff said

but I am hoarding more bits for when I do get on with the Barracuda

Pete · Post by **Pete** » Fri Jul 24, 15 5:46 am

Little car, big engine: the essence of hot-rodding!!

autofetish · Post by **autofetish** » Fri Jul 24, 15 8:37 am

Brilliant start your on build thread for the other car

We want to see all !!!!!!!!

Bozwell · Post by **Bozwell** » Tue Aug 30, 16 11:25 pm

this one's getting closer.

Barracuda still under wraps and will have to wait. maybe next year.

Pete · Post by **Pete** » Tue Aug 30, 16 11:34 pm

Blimey!

Hood scoop time??

Looking good

Bozwell · Post by **Bozwell** » Tue Aug 30, 16 11:47 pm

just clears.

RobTwin · Post by **RobTwin** » Wed Aug 31, 16 1:14 am

Love it, something different!

Pete · Post by **Pete** » Wed Aug 31, 16 8:00 am

A work of art

mopar_mark · Post by **mopar_mark** » Wed Aug 31, 16 9:08 am

Superb job

Bozwell · Post by **Bozwell** » Sun Dec 04, 16 3:32 pm

so since i'm going to be playing with the steering converting it to RHD and fitting a power rack I need to check the steering geometry.

so I knocked up this v

just a quick check. I just undid the torsion bar but need to remove it to get full bump, that said there is enough info to show the steering in standard form really sucks.

from full droop

to an inch away from full bump

a dramatic caster change and a minimum of 6mm of steering movement worked out at the tread diameter on just one wheel. i'm sure I can get much better bump-steer even with modifing the steering system. caster change is unavoidable with the antidive top arm set up but running a much stiffer torsion bar will limit movement.

now I can play with different track rod lengths and positions to see what happens.

Bozwell · Post by **Bozwell** » Sun Dec 11, 16 3:17 pm

ok so I messed around by undoing the torsion bar fully and took measurements.

then I shortened the track rod by one and a half inches and redid the test with the what would be the road wheel in the same position. (the rack i'm thinking of using is three inches longer than the drag link)

quick quiz, what do you think happened?

Bozwell · Post by **Bozwell** » Sun Dec 11, 16 3:21 pm

this'll be about ride height so it has over two inches of bump and three inches of droop.

Bozwell · Post by **Bozwell** » Sun Dec 11, 16 6:40 pm

no one want to guess what the bump steer did then

(this is one wheel remember so figures would need doubling for total toe-in)

so in totally standard form, taking ride height at zero, two inches of bump caused 50 thou (1.1mm) of toe out to three inches of droop at 120 thou (3mm) of toe in (170 thou tracking change over 5 inches). if you take just one inch each way at ride height, which is where the suspension will spend most of its time, it went from 35 thou toe out to 40 thou toe in. (that's 75 thou of tracking change over two inches)

maximum recommended is ten thou per inch of movement

and with the 1.5 inch shorter track rod measured one inch either side of ride height. 5 thou toe out to zero at ride height to 5 thou toe out! thats right, it has virtually eliminated bump steer

not what I expected either. (that's 5 thou of tracking change over two inches)

even at two inches either side of ride height it only moved 18 thou. only at full droop on the last inch it moved to 60 thou toe out.

so the Jag rack will work and work very well

Pete · Post by **Pete** » Sun Dec 11, 16 6:55 pm

Astounding Barry

All very clever and beyond me - now I know why I do Drag racing and not roundy-roundy!!!!!

All I need to know is 11 degrees of caster, zero camber, and about 1/8" Toe in at most!

Bozwell · Post by **Bozwell** » Wed Dec 28, 16 4:16 pm

so i did some more measurements. Caster, camber and bump steer on lock.

I can see why the standard suspension and K frame gets ditched, the readings are a joke.

nine degrees of Caster change over the full range. four degrees in just the one inch either side of ride height change. Camber changes by a degree over the same two inch range

also anything other than straight ahead the bump steer goes all to pot. reason for that is the drag link is held in place by the steering box and idler arm which are angled. basically the track rod changes angle by five degrees. when just a few 10's of thousandths can affect bump steer that much angle movement made too much difference. from 5 thou over one inch straight ahead to 50 thou over one inch on 15 degrees of lock.

at least a steering rack moves in a linear motion so that wont be an issue to change bump steer on lock and for the rest i'll just have to do what I can and put up with it.