yes Gary we did discuss it, it is definitely an option, but like you said it has to be done right.
Bob Cooper used corolla arms to quicken up the steering which apparantly works well, but he was hopng to have a better 'feel' with the rack, as he felt the cumulative play in all the joints in the datsun suspension gave the steering a vague feeling which gets worse a you gear up the steering, which can be a bit unsettling at high speed on gravel!
How is the sunny and the rallying going Gary? I've still got the sunny but am running a 1600 at the moment.

Interesting subject,

If it's a quicker turn from lock to lock you want there is another way. (nzdatman, did we discuss this a few years ago)

I know alot of people may not agree with this way but you can shorten your lower steering arms, this will give you a quicker lock to lock.

I have done this mod twice now on two of my rallycars with great success.

I must stress that this mod is NOT one to be even considered unless you have the relevant metallurgy knowledge and the correct welders to do the job properly.
It's not just a matter of cutting up your lower control arms and welding them up with the good ol' arc welder with GP rods under the house.
If not done correctly it can be very dangerous.

quick steering is nice in a race car and near a must in a rally car. yes the steering gets heavier but these cars were designed so old nanas could steer them easily on their way down the shops, not for competition.
my 1600 has about 2.2 turns lock to lock and it's not a problem at all. the steering is a little bit heavy but once you're racing you forget all about that.
Bob Cooper's rack conversion sounded really good- very guick ratio and lengthwise sounded like a good match. If you approach him and ask nicely I think he would help you out. He knows 1200s. I think it was rear mounted too.

Cheers guys, interesting to hear different opinions from both camps. Dodgeman, you are right, my car is going to be a racer with fat tread and wide track so anything that increases the steering load could cause issues... How ever my ex-partner had a mark 1 escort she raced with the big heavy pinto, wide tires, increased track and a small steering wheel, she is 5,4" and 50kg and never had a problem with steering so I just cant see converting to rack and pinion and increasing the gearing being such a big problem. I admit I dont know a lot about steering geometry but I know enough to foresee there being a lot of factors to watch out for. I dont want to try and simplify anything but surely it would just be a case of mapping all the pivot points of the original setup and making sure the replacement is as close as possible (tierod lengths and pivot points etc), hence another reason to keep the rack behind the crossmember...

the last time I heard from bob cooper which was a while ago now he was working on a rack and pinion conversion for his rallycar. maybe get in touch with him and find out if he ever finished it and let us know how he got on.

I looked at a starlet steering rack and they are close width wise and I think they could be made to work pretty well as they are only slightly wider than the distance between the bottom arm pivots. That means if you could get it the right place (assuming your motor isn't in the way of the ideal position you'd probably get a little bit of toe out bump steer, I obviously couldn't tell you how much though, not with out drawing it all up way of the ideal position
The other one I wanted to look at was a mini rack they have an excellent steering ratio but i wanted to check how long the steering arms were compared to the 1200 ones because a mini with 165's on it was hard work to turn with a little steering wheel.
one of the usa racers on this site uses a mini steering rack in his race coupe, i can't remember his name though, maybe bob i think.

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well its clean and shiney, but have a closer look at the width of the rack (to its pivots) and where the control arm pivots are. remember dat383 is a dedicated drag car - bump steer isn't a huge issue for a car designed to drive straight ahead.

I agree that a quicker steering ratio would be a big improvement, particularly for high powered 1200's. Its so much easier punting around late model turbo cars like the GTR and Supra at 10/10ths on the track than the 1200 because of their beautiful quick steering - corrections are quicker and more accurate. The Datsun needs alot more respect solely because of the slow steering response. Not so much of an issue for under 2L cars - you have alot more time to make corrections.

its not impossible, but its a fair old engineering exercise to get it right, and will be difficult to find a rack the right length. I was looking at this for my 1200 as soon as I got it (about a year ago). All the engineers I spoke - one who have been building space frame cars for years - told me to forget it. packaging a rack into a car not designed for one with limited space is not an easy thing to get right. if you have an A series you will have alot more room to play with, but then my opinion is you don't need a rack with those power levels. that's been my experience anyway.

Someone on this site has got a modified steering box, he changed the gearing and the bearings, i don't exactly remember who it was( i think it was whitesedan, but i could be wrong) so that is proof, that the standard steering box can be modified to do the exact same job as installing a 'rally' spec rack and pinion set-up, and alot less hassle too!

I drove a freinds gallant years ago and it was set-up for rally it had a modifyied rack and pinion that was 1/2 turn for full lock it was fun to drive on the dirt and felt more precise, espeically on the road, i spose that why people look at putting rack and pinion in a 1200, maybe?

I have looked into a few years ago and i was told that KB laser steering set-up is the way to go and readily available. There have been quite a few threads on this subject in the last few years.

The steering box is, among other things, a reduction drive. If you engineer in a steering system that provides fewer input turns for a given degree of wheel turn, then the gear ratio is higher & the steering effort is greater.

Since your car is a racer & you will be running 'fat feet' on the front, the steering load will be greater anyway, but to increase the steering load even further with a higher gearing will impose even higher input loads at the steering wheel rim.

Now, if you use a steering wheel of reduced diameter, & therefore with a reduced rotational leverage on the steering column by virtue of the reduced radius, then the input load at the steering wheel rim rises even further for a given degree of wheel deflection/time.

This will be good for your fitness program & I wonder if you will develop arms like Arnie once had.

I'm reminded of the old addage, ... be carefull of what you wish for, ..............
There are a lot of successfull Datsun 1200 racers that still use the old steering box, ... & for what I presume to be good reason.

You can make the stock Datsun 1200 gearbox less turns lock to lock ... just limit the turning radius, like the Escort has already. You won't turn as sharp, but it's less turns to lock.

What you really want is a quicker ratio gearbox.