I agree this project is not for a novice , I have changed my approach many times as i have discovered pluses and minuses in my geometry , as with any motorsport catergory it's a compromise to achieve a workable result . My aim is to build in as much adjustability as possible to try to cover all bases .

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well, that's bump steer fixed if you were able to fit the rack at the right height (often the sump will be in the way of that) and even then only if you had straight steering arms, which you probably don't, so that the outer pivot matchs the respective inner pivots and the LCA nd tie rod assembly ar ethe same length (most of the time you need the LCA pivot further out than the steering pivot because of the shape of the steering arms).

now what about your ackermann?

not trying to can the idea of a rack conversion, just pointing out it isn't that straightforward. I took the advice of a couple of spaceframe race car builders with over 15 years experience each and stuck with the steering box... if they don't want to take the job on, a novice has little hope of a good outcome.

Hey Wards, thanks I'll be PM'ing you asap...

ok back to the steering rack issue , i have a nissan micra rack mounted behind the crossmember on my ute . As you say your car is a racer so moving the inner pivots for the lower arms out 20mm a side to match the width of the pivot balls on the micra rack shouldn't be a problem, thats the bump steer fixed. also it's a power rack so as much caster as you like will be no problem ,any more info pm me for photos

Not wanting to diverge from the original topic but I think you have a very good point Rallytwit... I love the 1200 shape and style and I raced a 1200 coupe with a hot a12 in it for a few years before moving on. This current build is a perfect example of the snowball affect when someone starts a project with out a clear goal in site. Originally I planed to strip and rebuild the 1200 with a worked a15, 5speed and H165 diff... Due to another project going pear shaped I happened to have a spare 4AGZE sitting around. One thing led to another and I changed course, so I need a new box and I had to freshen up the motor as it was in an unknown condition. I'm not a huge fan of the factory supercharger set up so I decided a turbo would be a nice upgrade. Over the time of ownership I got to know Lynn Rogers well and he pointed out while refreshing the motor it would make sense to "tweak" it a bit. So now I have a fully balanced worked forged 4AGTE with a T4/T3 hybrid turbo set up to push 210 - 230kw (depending on boost settings) so I have to cage the car and seriously think about suspension/traction/brakes... I've been loving this project and I've decided to stick with no strict goal and see where I end up, probably in a lot of trouble... fun trouble. But back to your point, my 1200 is now a Datsun shelled Toyota on steroids. Not a Datsun 1200...

Thanks for the comparison it's interesting to see what other folks run. Belting out the maybe 95HP after recent head work my alignment varies as I would expect. Running about 5 degrees of castor 0 toe and only 1.6 camber (running a 185/13 tire)

Well we've strayed a bit off topic but I've often wondered at what point is a 1200 no longer a 1200. At my buddies fab shop we joke about a Cosworth DFV pushed back just beyond the front axle centerline, a Hewland transaxle and pull rod suspension...............but for me it always seems easier to just go back to a single seater rather than start spending serious dollars on the 1200. So I'm curious at what point beyond adding a rack and twin cam engine would most folks realize that XXXX dollars would be a purpose built race car? OR is it a case of lets see what kind of fire breathing 1200 can I build?

well my old coupe handled better so I'll start with that:

6deg castor, 4and a bit camber, 0 toe static which would be a little bit of toe out dynamic. I used to tweak this a little at the track if I felt I needed to, with the old string-line method. flares and gaurds were cut to allow as much castor as I could get.

the white coupe has 5deg castor, 3.4camber and 0 toe. It would be a little more now since I lowered it to get the roll centre down a bit. with the +12 offset 15x7" front wheels it didn't have any real need for flares to even be fitted on the front. I plan on fitting 8" +4 fronts shortly, and have trimmed the flares to suit

Yea I'm of the same school of thought about caster, while fitting my flares to the front guards I've moved them as far forward as I can to allow for the caster I want (also trying to stretch out the wheel base as much as poss). However caster does make the steering heavy especially when you push it to far... Hey L18_B110 I too would love to know what your front end setup is (oh and your rear as well while your at it :) )

I'll check my alignment sheet for you tonight then that's power at the wheels too btw, closer to 400 flywheel bhp but also probably closer to 1900lb

alignment is not much different to my old 146bhp at the wheels L18 engined 1200. You want as much castor as possible in any track car.

OK a 300HP 1200 given the 90 inch wheelbase and 48-49 inch track ummmmmm yeah a racing rack would be a must.

If folks are running 300 hp 1200's I sure would like to how much caster and toe they're using.

On a differant note 300 HP in a 1700lb car is darn near Group 4 Specs............at the very least it would be a match for 70's Grp 2 machines.

Tom