mustard-z Posted November 14, 2003 Share Posted November 14, 2003 I'm looking for some help/insight on some mods for my 78 autox car. here is what i've got now: 78z @ 2550lbs with 1/2tank and driver 13x8 wheels with kumho ecsta v700 rubber stock brakes front/rear ST swaybars ST springs Tokico Illumina's front/rear Adjustable control arm bushings front/rear This is what my setup should look like next year: 78z @ 2300lbs with 1/2tank and driver 15x10 or 16x10 with some type of slick 300zx rotors with toyota 4puc calipers coilovers with spring rates approx. 250/275 or 275/300 (haven't decided) camberplates ST swaybars Tokico Illumina's front/rear Adjustable control arm bushings front/rear My car is going to be dedicated FP autox'er with no or VERY little street driving. I am going to gut it and add fiberglass fenders/hood too. Am I on the right track with this? Can 16x10 wheels fit under ZG flares if the fenders are trimed out? Will my 140hp @ rear wheels be too weak to push the car sufficiantly? Has anyone used the MSA coilover/camberplate setup? Thanks, Aren Quote Link to comment Share on other sites More sharing options...
Guest NorCalZ Posted November 14, 2003 Share Posted November 14, 2003 work on power adders later, 140 is good. If you can just keep your momentum which it sounds like that setup will help a lot then you're cool. Later work on gettng to 230 or so hp. Get a nice hot cam and head work and flywheels really help yank you out of corners. Quote Link to comment Share on other sites More sharing options...
blueovalz Posted November 14, 2003 Share Posted November 14, 2003 Someone correct me if I am wrong, but I think you'll find a better sizing of racing tires if you stay away from the 15" and go with the 16" wheels. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 14, 2003 Share Posted November 14, 2003 I was under the impression that for slicks there are a lot more available in 15's. DOT tires I'm not sure, probably about equal. I've got some Yokohama A005 slicks that I listed in the Buy/Sell/Trade forum and no one was interested. $200 for a set of 4, about 80% to 90% tread left, bagged and treated. Might be a good deal for you while you sort out your suspension. They are a little hard for autox, but you don't want to burn through a bunch of expensive soft slicks getting the car set up. I've got 8 tires that I'm selling. Search that forum for more info. A competitive FP car will have a lot more hp than what you currently have, but I suppose it all depends if you want to start out with a nationally competitive car, or work your way up. Look to spend huge $$$ to start and be competitive right out of the box. Jon Quote Link to comment Share on other sites More sharing options...
zlalomz Posted November 14, 2003 Share Posted November 14, 2003 Visit http://sth2.com/Z-car/ to see what the current fastest FP Datsun Z in the nation has. I get my used slicks from Roger Kraus Racing shipped to me. They are much cheaper than new slicks and work great for autocrossing. FP is fun but lonely. I didn't run this year as I worked on my track car but when I do there is only the National champion BMW and a very fast 914-6 here. Quote Link to comment Share on other sites More sharing options...
mustard-z Posted November 15, 2003 Author Share Posted November 15, 2003 Thanks guys. Right now I am fairly competitive in the local clubs in OR. I'm just looking to go faster and keep up with the club prez in his Sunbeam Tiger. I kind of like the idea of working up to a more competitive car. My first year I drove only on street tires, this past year i drove on autox tires. Next year I plan to drive on slicks. I like to drive the car and get to know it. Right now it is very tame, but turns good times with my competition. I'm not worried about making a National's worthy car, cause I definately don't have the money for that. Some of my concerns with slicks were finding common sizes, as I am not ready to shell out $200-300 each for new slicks. The compound won't matter as much either I think, because of the extra rubber on the road and the fact that slicks. It should be better over all. Have any of you had problems getting the back to come around? I've swapped an R160 3.7 lsd into mine and it pushes bad. It seems everyone I talk to seem to think that z's are tail happy. I'm just trying to get mine to really step out and let me drive it with throttle. I've thought about stiffening the rear or softening the front to try and help, but I think that adding camber and rubber to the front should help the turn-in. Jon, I may take you up on that offer. I'll need to see about finding a steel wheel with the backspace to accomodate the coilovers and fenderflares. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 15, 2003 Share Posted November 15, 2003 The two biggest assets in my car are camber and caster. I've got camber plates and adjustable control arms to get about 3 to 3.5 degrees neg camber and adjustable TC rods for 5 degrees caster. I used to have a horrible push. Not anymore! Jon Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 15, 2003 Share Posted November 15, 2003 The two biggest assets in my car are camber and caster. I've got camber plates and adjustable control arms to get about 3 to 3.5 degrees neg camber and adjustable TC rods for 5 degrees caster. I used to have a horrible push. Not anymore! Try Diamond Star Racing wheels. They'll custom build any offset you want, and you can get a spun steel 15x10 down as light as about 18 lbs. Sorry about the double post. OOPS! Jon Quote Link to comment Share on other sites More sharing options...
260DET Posted November 15, 2003 Share Posted November 15, 2003 Don't do autox myself but to get the back of the car to come round I would increase the rear anti-sway bar size. Its a fairly quick and easy thing to do during a test session, there are several stock sizes to chose from so keeping the cost down and it should not be detrimental to your front end grip. The other alternative along similar lines is to reduce the size of the front sway bar. One thing I would not do is to go bigger than stock sway bars. Quote Link to comment Share on other sites More sharing options...
mustard-z Posted November 16, 2003 Author Share Posted November 16, 2003 Jon, What you have done seems to be the direction I am heading. I have .7° camber in the front and am only using 3/4 of the tire because of it. I think just getting camberplates on the front will help me use all of the front tire in the turns. The diamond racing wheels are exactly what I was thinking. I know they are able to make them in just about every bolt pattern/size/backspace. I just need some idea of what "I" need. I think installing coilovers/camberplates should be my next project because of this. I also need to do a bit of research on common 15 & 16" tires and find which is more plentiful. 260DET, I have been thinking about swaybars, I've been thinking about moving to a 1" bar in the front instead of an 1-1/8" bar. I just need to find one. Quote Link to comment Share on other sites More sharing options...
gramercyjam Posted November 18, 2003 Share Posted November 18, 2003 FWIW, I think that buying the Illuminas are a mistake. Go with the Koni 8610s, they aren't that much more but are a better shock. I think you'll be happier with them in the long run. You will want to go with stiffer springs down the road and Illuminas won't handle them. I suggest lowering the car before fooling around with the camber - it will all change after lowering (You will need to lower the car to be competitive in FP). Same for the wheels - don't spend a lot on wheels until you get your coilovers on as they may not fit the way you wanted them to and your tire choice may change as you get more competitive with the car. Check around and see what "everybody" is running. Not that everybody is right, but a lot of them have been developing their cars for many years and with wisdom comes from experience. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 18, 2003 Share Posted November 18, 2003 Gramercyjam has it right, I think. I wish I had known about the differences in the Konis and Tokicos when I bought struts. One advantage to the Illuminas is that if you are still driving to the events you can turn the shocks down before you hit the road so they don't destroy your spine. At present I haven't run in a little more than a year, but before I moved to the land of rain and rust I used to drive 2 hours to events with 4 slicks in the car. Three wedged in the back and one riding shotgun. Oh, and I had my tools, my jack, my helmet, and my crate full of spares... a whole Z full of crap. Hopefully I'll be trailering the car before I go again. I think if you're going to get really serious with FP you'll probably end up with coilovers and camber plates anyway, so I don't really see any harm in doing that now, but if you're trying to go cheap you can get a set of coilovers like the ones from modern motorsports, then you won't be paying for that aluminum hat which you'll get rid of when you do go to camber plates. Jon Quote Link to comment Share on other sites More sharing options...
johnc Posted November 18, 2003 Share Posted November 18, 2003 The compound won't matter as much either I think, because of the extra rubber on the road and the fact that slicks. Bzzzzzzttt! Compound is the most important consideration. Much more so then tread width, etc. I'll take a Hoosier 35 compound and give up 3" tread width before I'd go with a 45 or a 55 compound for autocross. FWIW, I think that buying the Illuminas are a mistake. Go with the Koni 8610s, they aren't that much more but are a better shock. Agreed. Can 16x10 wheels fit under ZG flares if the fenders are trimed out? Fit fine with 5" of backspace. I'm running 16 x 10s on my 240Z using 265/45-16 Kumho V700s and/or 275/45-16 Hoosier A3S03s for autocross and Hoosier 22 x 10 x 16 R45 for some track events. Quote Link to comment Share on other sites More sharing options...
johnc Posted November 18, 2003 Share Posted November 18, 2003 FYI... Hoosier always has a sale at the end of the year for discontinued/overstocks. Here are some 15" slicks that would work well on a 240 with 15 x 10 rims. 43387R35 23.0X10.0-15 R35 A 11 $80.00 43387R45 23.0X10.0-15 R45 A 36 $80.00 They are 23" tall, 10" tread width, 15" diameter ply R35 and R45 compounds. Quote Link to comment Share on other sites More sharing options...
gramercyjam Posted November 18, 2003 Share Posted November 18, 2003 Jon, I was gonna do camber plates first about a year ago, bought them, and then thought better of installing them right away. I'm glad I waited. Initally, people want the plates to add camber to the car. What happened in the evolution of my car is after lowering, I had more camber than the tires (Hoosier bias ply slicks) could handle and if I had installed the plates to add camber earlier, the plates would have been located such that I wouldn't have enough adjustment to take out the excessive negative camber. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 18, 2003 Share Posted November 18, 2003 Interesting. What kind of plates are they? My ground control "roadrace" plates can adjust me between about 3.5* to 1.5* with the control arms lengthened. With the stock control arms I think I could get to about 2.25*. I think you also may be running a little lower than me ride height wise. Your bias ply tires are the main difference there, though, as you know. With a radial the plates are probably more necessary. Jon Quote Link to comment Share on other sites More sharing options...
mustard-z Posted November 19, 2003 Author Share Posted November 19, 2003 Well, I've already got the tokico's so i'm going to wait until I am ready to run super-stiff springs(aka 400#) before I go and buy some new koni shocks. After reading some other posts, it seems 300 lb springs are about the limit on the tokico shock? What should my initial spring rate be? 250lb front and 275lb in the rear? Also, lowering the car; Mine is about 2" to the frame rail and it's a pain to get on my trailer. What kind of ride height should I be looking to end up at? It seems the lower the better, but damn, you need to get it on the trailer. This past year I drove to events with the autox tires in the car with the jack and all that crap. The car feels like a caddy on the cruise up, i'll give you that! I would definetly take a trailer any day though. 8) Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 19, 2003 Share Posted November 19, 2003 That's really low. Do you have any suspension left at that height??? You may want to run a little higher until you get some things changed around, like sectioned struts, raising front control arm pivot height, and some adjustable TC rods, possibly raising the TC pivot too. Right now I'd venture a guess to say that your control arms are pointing way up, and that as the suspension compresses you are losing caster due to your ride height. I think lower is better, but with stock pivot points too low is not good. Maybe you've already done all of that, I don't know. 250/275 should be fine, maybe 225/275. I started with 250/250 and dropped to 200/250 to get help get rid of some of the push I was talking about before, before I got the custom control arms and TC rods. Jon Quote Link to comment Share on other sites More sharing options...
gramercyjam Posted November 19, 2003 Share Posted November 19, 2003 Interesting. What kind of plates are they? Old style ground control plates. On my '73 I actually needed to modify and extend the tops of the rear strut towers outward so I could get mount the plates in such a way that there was enough adjustment to take out the excessive camber. Quote Link to comment Share on other sites More sharing options...
johnc Posted November 19, 2003 Share Posted November 19, 2003 Also, lowering the car; Mine is about 2" to the frame rail and it's a pain to get on my trailer. What kind of ride height should I be looking to end up at? It seems the lower the better, but damn, you need to get it on the trailer. With the 13 x 8 wheels I can see the car getting that low but its not the best idea. Ian Stewart autocorsses a 240Z in the CSCC region and he runs 13 x 8 wheels. His ride height (measured at the front rocker panel seam) is a little over 4" if my tape measure eyes are right. With a 225/50-15 tire (about 23" in diameter) your ride height should be 5" measured at the front rocker panel seam and with a 25" diameter 16" tire the ride height should be a bit over 6" measured at the same point. All of this is assuming the struts have been sectioned so that you get back some bump travel and you're running bumpsteer spacers. Without the sectioning your car is basically riding on the bump stops and is skating. Quote Link to comment Share on other sites More sharing options...
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