I started making a list of suspension pieces I need and need some help with sway bar size. I never drove my car before I started tearing it apart so I have no base line. I plan on doing some weekend racing with the car and this is by no means a daily driver. (75% street, 25% track) I want the ride fairly stiff and handling on the loose side. What's the best swaybar sizes for this set up? I'm also putting on strut bars on the front and rear if that makes any difference.

I have the same dilemma in finding the right setup but some people who I trust in their judgement have told me to try out 25mm front and about 14mm rear.

They also reckon the rear bar is optional. you may love it or hate it.

might be an idea when you buy to see if you can swap it over if it does not work out.

biker

I had a 1" Quickor front anti-roll bar and 3/4" Interpart rear bar on my (since sold)1971 240Z and it handled fairly neutral. I used it for street and autocross and had a ball driving it. It also had Bilstein struts, and solid suspension bushings (aluminum/delrin adjustables), but no strut bars. I really liked the way it handled, and intend to replicate that handling package (without the solid bushings) on Bambikiller one of these days.

a complete sst set up with tokico struts on my 72, and it was the best handling car i have ever owned. sst sways front and rear 1 inch and 7/8's accordingly. sst springs, with tokico blues.

it rode well but stiff, and handled like nothing i have ever owned before. i did have a front strut bar and i like it, it does help eliminate front structural flex.

thats what i enjoyed even more then my coil over set up but then again that was something totally different.

good luck with whatever you decide on

Depends on so many things, including engine hp, spring rates, etc. Basically, the more power the lighter the rear bar, unless you like power oversteer. With my 300hp engine I tried doing without a rear bar at all but ultimately, on a racing circuit, there was just too much body roll although my lap times were reasonable.

My spring rates are 250 front, 300 rear. The front bar is 28mm dia (and adjustable) which seems about right. For the rear I'm guessing that 16mm will be about right. Both stock front and rear bar mounts are strengthened, the stock rear mount, particularly, flexes.

After reviewing anumbe of catalogs, the 1" front bar seems almost universal. The rear 3/4" is common with the 7/8" rear only being shown on 280Zs. I would guess due to the higher stock ride and increased weight/drop in Horse Power.

I have a 1" and 3/4" combination going into my current '78 280, with Energy Suspension bushings.

ecp48

ecp48

FWIW,

I started suspension work 1 year ago on my '73 Autox car. After each mod, the car was tested at several events. Believe me, I have learned a lot in the process and taken it from mild to wild with steps in between.

Stage 1 - Stock 240Z springs, stock frt/rear sways, urethane bushings all around, tokico blues. 14" Falken Tires. Result - Generally terrible handling. Almost uncontrollable oversteer.

Stage 2 - Cut 280Z stock springs. A little more stable, but still generally terrible.

Stage 3 - Coilovers with 10" Eibach ERS springs. 250# frt/275 # rear. Lowered several inches in the front. Sectioned struts. Tokico Illuminas. Custom built top strut mounts. New 14" Falken Azenis. Result: Much better, can see future potential, but oversteer is still a major inhibitor. Cannot lower the rear as much as I would like because of ground clearance of the exhaust.

Stage 4 - Replaced Falken Azenis with 15" Hoosier and swapped stock diff for R180 4.11 LSD. Shorten headers and fabbed new exhaust so car could be lowered another inch without dragging it on the ground. Result: Now we are getting some where. Car is much more predictable, still some oversteer, but it is much more controllable and not really a problem.

Stage 5 - Replaced springs with 7" Eibach ERS springs. 300#Frt/300#rear. Changed to 1" front & 3/4" rear sway bars. 16X10 Hoosier slicks. The car is so low that rockers panels are now maybe 2" off the ground. There is an extreme amount of rear camber - too much for these fat Hoosier. Result: Yea Baby! This is the way it should be. I can't hardly break it loose in the corners. A little understeer midway through sweepers, but that should be able to be tuned out.

Stage 6 - Camber plates and Strut tower bars. Result: Not tested yet. Expecting less tire wear and additional grip from improved geometry.

Stage 7 - I should probably lay off the suspension mods for a while, learn to drive and start doing something about increasing power!

Enjoy the ride!

--John