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-   -   Project 240Z race under way (https://www.zdriver.com/forums/motorsports-14/project-240z-race-under-way-5783/)

AllmyZs 10-10-2003 09:55 AM

Just curious, Where do you live at in Idaho? I am in Chubbuck in Southeast Idaho. We dont have any tracks over here that I can find. I have a 78Z that I am preparing this winter for track use. I know it is going to take a couple of years to get back to how I was in the mid 80,s. I use to race every weekend in my 70 240Z out in Ca. Either at the fair grounds or at Sears Point or laguna Seca.

zlalomz 10-13-2003 02:49 PM

Hey Mike, it looks like you have a similar set up to my green car.
You will need to stand those slicks upright compared to radials. I hope camber plates came with that. I have only 3/4 of a degree negative camber. If you can't get camber plates yet, in the rear I drilled holes 1/2 inch upward. I had to weld a plate for one hole that was near the center hole. Camber bushings and slotting fixed the front.
My orange car with Ground Control newer plates all around couldn't get the slicks upright enough in the rear. Now I have another set of old style Ground Control plates. I am going to use the newer ones from the orange car up front and the old style in the rear. The EP racers with the new camber plates in the rear flip the center piece with the bearing around. You can't adjust them this way so camber bushings are used in the lower control arms.
You will be amazed how well slicks work compared to even the hottest BSP tires. Hang on! Steve

Spudz 10-13-2003 03:10 PM

Hey Steve,
I passed on Kyle set up... I really want to run more spring then the Tokicos allow me to. I figured if I was goig to spend that kind of money I might as well do it right.

Andy Craig swears by the Advance Design inserts in the 280/late260 housings and thats what I think I am going to try and do.

I am going to sell the 240 and use the 260 as the race car . I will have a few photos posted of my 260 when I get a chance this weekend.

My goal is to get at least the suspension, brakes and LSD done by the June Z Car Nationals in LA :D My motor will have to remain pretty much stock until next season. Besides its all about seat time , Right !

I will be using the EMI camber plates to set up the camber , also Erik also mentioned using the adjustable camber bushings as well.

I need to grab me a Road Race GCR , so I can check out whats legal in E Production road racing to see how to set the car up legally .

Thanks,
Mike

tube80z 10-14-2003 10:08 AM

Mike Wrote:
I passed on Kyle set up... I really want to run more spring then the Tokicos allow me to. I figured if I was goig to spend that kind of money I might as well do it right.

Andy Craig swears by the Advance Design inserts in the 280/late260 housings and thats what I think I am going to try and do.

I would concur. My 240Z was originally on tokicos with spring rates in the 250 range. I put the advance design shocks on and went with spring rates of 450 front and 400 rear. I'm usign a 7/8 adjustable front swaybar and a 5/8 rear. I'm thinking of going higher on the rates.

I have a track that I can test at (http://www.ssccmedford.com/Track.htm) and with the old setup I could lap the outside at a consistent 48.4. Changing to advance design shocks and doing a few bump and rebound adjustments dropped this time to 47.4. With the stiffer springs I could reduce the ride height an inch and this dropped my times to 47.1.

Driving with these is quite different. The AD shocks are digressively valved so the turn-in is much quicker but overall, even with the stiffer springs, the overall ride is softer. But in the pits you'll swear you have no suspension travel at all. I typically start with no rebound and add some only as little as needed. I have yet to run more than a turn of rebound. The Medford track has FIA curbing and these shocks seem to work well over the curbs.

The rest of my suspension is custom tubular control arms (front and rear) using heims and not the offset bushings. I wouldn't use these for a prepared car as I have had issues with the tire grip slipping them.

For camber plates I would recommend the GC ones as they have a special design where the spherical bearing doesn't take the load and this is fed into the camber plate. If the EMI plates don't also do this you'll need to replace these from time to time.

The biggest change I have coming up this winter is that I'm doing work to reduce the scrub radius, add set of mulit-link struts, and some steering enhancements to increase SIA. I'm currently working on a front and rear suspension cradle that will triangulate the front suspension too. I'll post some pics later this winter if there is interest.

Spend the money on advance design and the stiff springs. They work! I easily set NHA GT-2 records at Bible Creek and Bogus Basin and have been beating up on the Formula Fords at the Medford Autoxs. Pretty impressive for an old beater Z.

Cary
FP 240
Tubeframe tube80Z emod project

zlalomz 10-14-2003 03:35 PM

Hi Cary, I was wondering with spring rates in the 400lb. range. do you have a rollcage tied into the strut towers or is it working fine without a full cage on a road course. Vic Sias had success in BSP with no cage and 400lb. springs and Advance Design struts. Tom Holt seems to like his struts and springs but he has more of a rollcage. Also, how is your E-mod car coming. Steve

Spudz 10-14-2003 03:45 PM

Steve and Cary,
That was going to be my next big question . I have seen a ton of different ways that cages have been installed. I know that certain classes don't let you penetrate the firewall and some do.. BSP doesn't and GT2 and E Production do. I was going to have a freind who is a fabricator do mine , but I want to walk in and tell him exactly what I want :)

One thing I did notice that with that engine plate the Bimmer guys used on the
F Prepared car you could eliminate the cross bar over the cam cover and still tie the strut towers in.

Mike

tube80z 10-14-2003 04:43 PM

Hi Steve,

I have a cage that connects everything together. The rule of thumb that I've been told is that you need at least 5 times your wheel rate in torsional stiffness. My car is has 4000 ft-lbs per degree right now and it could be made a little better with some more tubing.

I've never tested a 240Z that hasn't been modified so I'm not sure what the stock number would be. I asked around but got a lot of blank stares last year. My tube car, which is really more of a backbone chassis, is currently at 8500 and I don't yet have all the side bars in but I doubt they add much.

The EMOD car is almost done from a chassis standpoint and I'm using some of it's suspension on the unibody car (struts, springs, rear control arms, etc.). I can't transfer over the front stuff but plan on making some changes anyway. I've basically ran out of money so even though I can finish the car I can't afford to build the motor, which will be next years project. So in the meantime I'm going to put the inline-6 into it and run it in FP as a GT-2 car. It will have to have a lot of ballast but I should be able to balance about anyway I want.

zlalomz 10-17-2003 05:32 PM

The only way I have seen torisional stiffness measured was in a Herb Adams book. Taking a known length of tubing and attaching it perpendicular to the frame then adding a known weight to it, measuring the droop and plugging it into the formula he had. My cage has a few more diagonals to be welded in it, then I was going to dig out the book and try it. If I remember correctly the "known weight" was Herb standing on the tubing. How did you measure yours?

tube80z 10-17-2003 09:16 PM

Hi Steve,

I did pretty much what Adam's showed except that I did it on opposite corners as I wasn't smart enough to lash the car down. I've also ready you can do the same thing by just letting the car rest on diagonals with it's own weight.

Cary

Spudz 05-17-2005 09:15 AM

Hey Guys,
I am bumping this back up to a work in progress thread.

After two kids in the past three years I am ready to get back
at the project. I will if possible be using take off parts from
other racers to see what stuff is still collecting dust in garages.

The car is running fine now.. I do want to fix a short to one of the
rear blinkers , so I can drive it around . I don't want it to be a trailer
queen just yet. I want it to be available for some driving schools and
open track days.

I am waiting on a reply from someone who has adjustable sway bars that
he wants to sell. Once this happens to rear suspension comes down and
new bushings go in :)

Stay tuned !!

Mike


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