1966 Barracuda X's 2

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Dave81
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Post by Dave81 »

Hats off to you sir........as from reading your post it's like a foreign language. I take it you can see light at the end of the tunnel regards getting it setup?
Dave Tildesley.....MMA-081
72 Dodge Dart
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I wanna go so FAST i think i'm going to DIE!..........Then i'll shift into second!

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Bozwell
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Post by Bozwell »

probably didn't matter with crossply tyres and sloppy steering at the time but to sharpen the handling it needs to be changed.

been reading up on dropping the K frame down a little. this'll gain a little more rack clearance and I should be able to re-raise and centralise the engine as it is biased to the right to clear the huge power steering box.

from what I read doing this mod is what the factory did to get clearance for the big block in the later A body. also been reported it can help to reduce bump steer.

I shall drop the K frame half an inch and re measure bump steer to see what that does.
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Pete
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Post by Pete »

We dropped the "K" frame 1" on the Barracuda to help with clearances, etc; but it plays merry hell with the LCA bushes. It can be done though.

As it was a track-only car we did not even bother to check bump steer, etc...
Pete Wiseman; Cambridge.

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Bozwell
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Post by Bozwell »

so i put the steering back to stock and dropped the K frame by 0.575 inch.

and the result is YES it does drop bump steer to just a few thou. virtually eliminated completely at one inch either side from ride height. Camber and Caster gain are unaffected.

with the shorter track rod to simulate the rack i'll be fitting it is still excellent apart from the last inch of bump and droop where it jumps a fair bit but still within the original measurements. so it has four inches of travel with very little bump steer.
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Bozwell
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Post by Bozwell »

this should show the differences easier than just numbers.

Image

Green is the standard factory set up
Pink represents just fitting the rack
Orange line, which is the best at present, is just a K frame drop on the standard steering.
Blue is the rack and a K frame drop

so looking at the graph my best option is a very slight K frame drop for the rack conversion but there is no more point experimenting until I have a rack in place to fine tune as the suspension arms will need setting into the best position for Caster etc before hand.
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Pete
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Post by Pete »

Most impressive! 8-)
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Bozwell
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Post by Bozwell »

Image


back onto the job in hand. got the dash out so I can modify it to RHD. dash should be easy as I can hide most of the weld behind the crash pad.

no holes found, just a little surface corrosion to the air intake box which will just need treating and painting.

Image

Image

all looks very straight forward at this point. :thumbright:
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Pete
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Post by Pete »

That's a nice, Solid LHD car you have there, Barry ;)
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Bozwell
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Post by Bozwell »

Image


dash screwed to the bench ready for the chop :P
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paolo_mangusta
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Post by paolo_mangusta »

that K frame drop is a very interesting tweak! Unless I'm misunderstanding, as the steering is bolted to the K frame, the effect is coming from the change in the relationship between the lower and upper suspension points, and how the line between them relates to the pivot points of the track rods - is that right?

I've seen people move the box and idler to correct bump steer on A-bodies, but never heard of the K-frame drop before. Is the effect on the camber curve good,bad or negligable?!
'64 Barracuda
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Bozwell
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Post by Bozwell »

i guess raising the upper arm mounts would have the same effect.

from experience with various vehicles just a few millimetres of change in the steering pivot point (raising or lowering a rack) makes a huge difference in bump steer. more than you would think.

another problem with the Barracuda steering is the pitman and idler arms are angled so on a lock it is lowering the inner joint pivot height which drastically effects the bump steer. with the lowered K frame straight ahead is very good but even a slight lock bump steer is terrible again. with a rack moving in a linear motion this shouldn't be an issue.

Camber change is slightly reduced.
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Bozwell
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Post by Bozwell »

Image

Image


:P
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Pete
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Post by Pete »

:thumbright: :thumbright: :thumbright:
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drewcrane
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Post by drewcrane »

wow great thread,incredible work :thumbright: :thumbright:
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Bozwell
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Post by Bozwell »

decided to go Gunmetal and Black for the interior

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and going to have a go at remaking the crash pad

Image

Image

bit of carving to get the correct shape then it'll be covered in Black Vinyl. the top of the dash will be covered in Black Moquette which'll look like it's flocked but will stop any glare.
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