Duke's'72 Carbed KA project

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duke
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Re: Duke's'72 Carbed KA project

Post by duke »

I finally had a chance to get my car on a set of proper corner scales yesterday. I'm very pleased with the result. All it took to get the cross weights to 50/50 was two turns on the front right coilover. Also pleased at the weight with me out of the car. It would be cool to loose 50 lbs and get the car under 1900 lbs, but drastic measures might be necessary for that, and I'm not quite sure I'm ready to get that crazy. Any weight loss measures will be concentrated at the front though, at an attempt to improve the F/R weight distribution.

All weights are with 1/4 tank of gas (~3 gallons, which is what I typically run when autocrossing).

Total weight without me.

ImageTotal_WO_Driver by Eldukerino, on Flickr

Total with me.

ImageTotal by Eldukerino, on Flickr

Rear.

ImagePercent_Rear by Eldukerino, on Flickr

Front.

ImagePercent_Front by Eldukerino, on Flickr

Right front/left rear cross weight.

ImageCross_RF_LR by Eldukerino, on Flickr

Left front/right rear cross weight.

ImageCross_LF_RR by Eldukerino, on Flickr

You may notice that there is a small amount of fluctuation in the weights, I just chalk this up to "noise" in the scales and ignore it.
Duke Schimmer

'72 2-Door 510
"Simplify and add lightness."
dat5102dr
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Re: Duke's'72 Carbed KA project

Post by dat5102dr »

whats the level (bouldering)?
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duke
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Re: Duke's'72 Carbed KA project

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dat5102dr wrote:whats the level (bouldering)?
That picture is of a problem called "The Drawing of the Three". It's up on Donner Pass in Tahoe and goes at around V11.
Duke Schimmer

'72 2-Door 510
"Simplify and add lightness."
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two_68_510s
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Re: Duke's'72 Carbed KA project

Post by two_68_510s »

duke wrote:
dat5102dr wrote:whats the level (bouldering)?
That picture is of a problem called "The Drawing of the Three". It's up on Donner Pass in Tahoe and goes at around V11.
OK, I'm a dumb old cus, what the heck are you guys talking about? ;)
Joel

2 '68 510 2 door sedans
'95 240SX


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TheHeretic
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Re: Duke's'72 Carbed KA project

Post by TheHeretic »

Where did you go to get the corner balancing?
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loungin112
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Re: Duke's'72 Carbed KA project

Post by loungin112 »

two_68_510s wrote:
duke wrote:
dat5102dr wrote:whats the level (bouldering)?
That picture is of a problem called "The Drawing of the Three". It's up on Donner Pass in Tahoe and goes at around V11.
OK, I'm a dumb old cus, what the heck are you guys talking about? ;)
Rock climbing pic from duke. Bouldering is climbing a route without a rope, usually only about 10-15 feet verticle.

I used to climb, wish i kept it up as it was fun and kept me in great shape.
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duke
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Re: Duke's'72 Carbed KA project

Post by duke »

loungin112 wrote:
two_68_510s wrote:
duke wrote: That picture is of a problem called "The Drawing of the Three". It's up on Donner Pass in Tahoe and goes at around V11.
OK, I'm a dumb old cus, what the heck are you guys talking about? ;)
Rock climbing pic from duke. Bouldering is climbing a route without a rope, usually only about 10-15 feet verticle.

I used to climb, wish i kept it up as it was fun and kept me in great shape.
Yeah, what he said. Rock climbing is one of the greatest passions I have had in my life. I'm not sure what I would be doing with myself if I had never started climbing.
TheHeretic wrote:Where did you go to get the corner balancing?
I did it myself. Borrowed the set of scales from a friend and spent an afternoon messing around to get it all balanced. I know that there are a few shops at Sears Point that offer it as a service though.
Duke Schimmer

'72 2-Door 510
"Simplify and add lightness."
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DADZSUN
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Re: Duke's'72 Carbed KA project

Post by DADZSUN »

duke wrote:After much deliberation and planning, I have finally decided to dive down the rabbit hole of installing rack and pinion steering on my car. Like many 510's out there, my steering box was badly worn, and definitely one of the main weak points of the chassis. I have seen many different iterations of rack and pinion installations in 510's, some better than others, and in this research I set a few ground rules for what I wanted.

1. Keep the rear steer setup-I didn't want to have to make new steering arms, a new front sway bar, etc.
2. Keep the oil pan rear sump- With how low my car is, I really like the security of having the crossmember there to guard the oil pan.
3. Use a new rack and pinion- As awesome as the MR-2 rack setups that I have seen are, I don't like the idea of using something that is 30+ years old and can be difficult to find. Also, I didn't like how slow the ratio's are for most stock steering racks.
4. Make it bolt in- I want to use the stock steering mounts on the frame rails to mount the rack, essentially making it a bolt-in affair.
I'm about to dive into R&P conversion myself. Hoping to put a more serious Solo2 package together for next year and the steering is definitely my car's weakest link right now.

Since you & I have similar setups (carbed, rear-sump KA), I'm hoping to do something similar to you. I plan to run an MK1 MR2 rack with Cressida inners, and 2 x '72 outer tie rods. I also plan to run a Quaife 2.5 quick-steer conversion to basically have the rack as-new.

Not sure how the rack will span the underside of the block/pan, seems awfully tight in there... How much room did you allow for engine movement?

Also, I noticed your mounting bracket seems to do without bushings on the rack?
'72 Datsun 510 - MS KA24e, Watanabe, STI R180 & CV axles, R&P assisted steering
'76 Datsun 620 - VQ35DE, CD009, G35 suspension & brakes.
'76 Datsun 280z - Future track toy
Creativity outlet: www.datsunrestomods.com
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duke
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Re: Duke's'72 Carbed KA project

Post by duke »

DADZSUN wrote: I'm about to dive into R&P conversion myself. Hoping to put a more serious Solo2 package together for next year and the steering is definitely my car's weakest link right now.

Since you & I have similar setups (carbed, rear-sump KA), I'm hoping to do something similar to you. I plan to run an MK1 MR2 rack with Cressida inners, and 2 x '72 outer tie rods. I also plan to run a Quaife 2.5 quick-steer conversion to basically have the rack as-new.

Not sure how the rack will span the underside of the block/pan, seems awfully tight in there... How much room did you allow for engine movement?

Also, I noticed your mounting bracket seems to do without bushings on the rack?
I think I have about 3/8" between the top of the rack and the oil pan. My engine is very low in the chassis so there is really not a whole lot of room under there. I mounted the rack as high and far forward as practical, but in the end, it was a compromise between oil pan capacity and rack placement. I think the rack that I used is a little smaller in diameter than the MR2 rack, which gave me a little more room to work with as well.

Yes, the rack is solidly mounted. In fact, the only compliant bushing in all of my suspension is the polyurethane mounts for my front anti-roll bar. Because my car is primarily an autocross car, I wanted as responsive of steering as possible, hence the solid mounting.
Duke Schimmer

'72 2-Door 510
"Simplify and add lightness."
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DADZSUN
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Re: Duke's'72 Carbed KA project

Post by DADZSUN »

Thanks Duke,

Another quick question - what did you use for steering shaft/UJoints off the Datsun column to the Escort rack? I can't get a clear image from your pictures. Specifically, were you able to use just a single U joint off the Datsun column and another one down at the rack? Was the angle within the recommended ~30deg?

It looks like my MR2 rack can fit within my current KA rear-sump setup, that's the good news. More troublesome is the exhaust manifold clearance for the steering shaft and the steep'ish angle off the steering column down to the rack...

Ideally I'd like to run a Datsun -> generic single U Joint, generic shaft, generic -> Toyota MR2 single U Joint at the rack. I just need to confirm that the first angle off the column isn't >30deg...
'72 Datsun 510 - MS KA24e, Watanabe, STI R180 & CV axles, R&P assisted steering
'76 Datsun 620 - VQ35DE, CD009, G35 suspension & brakes.
'76 Datsun 280z - Future track toy
Creativity outlet: www.datsunrestomods.com
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duke
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Re: Duke's'72 Carbed KA project

Post by duke »

DADZSUN wrote:Thanks Duke,

Another quick question - what did you use for steering shaft/UJoints off the Datsun column to the Escort rack? I can't get a clear image from your pictures. Specifically, were you able to use just a single U joint off the Datsun column and another one down at the rack? Was the angle within the recommended ~30deg?

It looks like my MR2 rack can fit within my current KA rear-sump setup, that's the good news. More troublesome is the exhaust manifold clearance for the steering shaft and the steep'ish angle off the steering column down to the rack...

Ideally I'd like to run a Datsun -> generic single U Joint, generic shaft, generic -> Toyota MR2 single U Joint at the rack. I just need to confirm that the first angle off the column isn't >30deg...
Sorry it took me a while to reply. The steering shaft and mount is now a totally custom setup using mostly
Woodward Steering components. It uses 2 u joints and runs through the firewall in a different spot than stock. There is one u joint in the engine bay and another in the cabin, with a support bearing between the two mounted to the firewall. By doing all of this I was able to loose a little bit of weight, but more importantly, move the steering wheel down about 3 inches for a better driving position. This was inspired by rally cars and touring cars where you see the columns extended way back and down to position the driver further back in the car.
Duke Schimmer

'72 2-Door 510
"Simplify and add lightness."
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icehouse
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Re: Duke's'72 Carbed KA project

Post by icehouse »

We need updates.
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