74_5.0L_Z

OK, The new struts arrived today, and I have some more questions: First, I think I need to acquire some gland nuts. The struts that I removed from the rear were the old Koni sports (8641-1032). The gland nuts from those sat around the top of the strut insert and acted to center the insert in the housing. I assumed that koni would use the same gland nut for the 8610-1437, but it appears that I am wrong. Second, the box had a bag of parts. Some I recognize and some I do not. The ones that I recognize are the four nuts and rod end spacers. The ones that I do not recognize are two large OD steel rings, and two slotted plastic discs. The purpose of these last items is not immediately obvious. They were not included with my 8610-1149 struts that I put in the front a few years ago. Any help will be appreciated.

Thanks for the replies. I had to deal with the alignment issue when I did the front struts. For that I did as John suggested and made a mandrel to assure squareness and concentricity. I still have the mandrel and will use it for the rear. I guess my real concern was with losing too much droop travel in the rear. I have read somewhere on here that insufficient rear droop travel can create a snap oversteer situation. I obviously want to avoid that. Ideally what I'm hoping for is a very light preload of the spring at full droop. With my current set-up, The springs are unseated at full droop, and I have to guide them onto their upper perch when I lower the car off the stands. If all else fails, I'll come up with some droop limiters that are set at the point where the spring uncouples.

johnc put together a great write-up about sectioning struts about three years ago in the following thread: http://forums.hybridz.org/showthread.php?t=85960&highlight=section I followed his directions to the letter for the front struts, and everything worked perfectly. I am in the process of sectioning my rear struts for Koni 8610-1437race inserts, and I have a question regarding his write-up concerning the rear struts. Here are the instructions for the rear from the original write-up: The problem that I am having is this: The write-up suggests shortening the rear housing by 2.25" and then using a spacer below the insert of 2.25". The unmodified length of my housing is 16.75". If I remove 2.25", the inside length will be 14.5". From the Koni catalog the length of the 8610-1437race housing (Dimension A) is 13.07 inches. Also they suggest that the housing length is 0.04 to 0.16" shorter than Dimension A. Using 13" for the desired inside length (13.07 - 0.07). If I section my strut housing 2.25" and subtract 13", I get (14.5 - 13)= 1.5. So, here are my choices. 1. I can section the rear housing by 2.25" and use a 1.5" spacer below the strut. 2. I can section the rear strut housing 1.5" and use a 2.25" spacer below the insert. 3. I can section the housing some dimension in the middle and make up the difference with an appropriate spacer. johnc (and others), What is your suggestion? Have I made an error in my math?

When I was preparing the tubing in my cage I did as Johnc suggested. I would soak a rag or paper towels in solvent, and push / pull it through the tube until it came out clean. This worked well to remove the cutting oil and chips that accumulated during tube notching process. If you are using DOM mild steel or 4130 tubing, then there is going to be a thin coating of mill scale (inside and out) that cannot be wiped off with a rag and solvent. This coating needs to be removed in all areas that are going to be welded. To do that I used 80 grit paper, and then acetone.

The process you describe will probably work. The problem that you may encounter will be clearance for the header bolts. They are usually pretty close to the tube to begin with.

I still can't quite come up with anything...

Jon, Your weld on bracket will make the connection plenty strong enough. However, I think you may still have trouble with your tire hitting the T/C rod when the wheel is fully turned. Here is an image of my set-up and a drawing of the bracket. The dog leg in the bracket serves two purposes: First, it moves the T/C rod back away from the tire. Second, it aligns the force from the T/C rod with the rear most bolt on the control arm. This minimizes the bending moment seen by the dog leg of the bracket. The bracket is secured using 7/16" grade 8 hardware. The clevis is from QA1 (3/4-16 with 3/8" slot and 1/2" hole). I reamed the holes in the control arm and ball joint to match the holes in the bracket and get a close tolerance fit with the fasteners. The tube is 1 1/8" x 0.058 4130 with tube adapters from "ChassisShop" TIG welded in the ends. Dan

Jon, The design will work if you redo the plate on the control arm such that it also captures the outboard bolt on the ball joint. The current design places that bar in bending when you apply the brakes. The other issue that you may encounter is the tire rubbing the T/C rod when turned fully to the left or right. As you know, I had an issue with my T/C rod a couple of years ago. As part of putting my car back together, I reengineered my T/C rods similar to what you have. The plate that I use on top of the control arms uses the same two bolts as the stock T/C rod. A third hole in the plate lies on the line drawn between the rear-most bolt on the plate and the T/C pivot on the frame. I'll have to borrow a camera, so that I can post a picture.

If you look at the pictures that I posted above, you will see that the 245/45/16 tires have lots of clearance. This is on 16x8" wheels using a 5 inch backspace. So obviously, the 245 fits easily on the front. This same tire and wheel combo rubbed the lip of my stock fenders. Here is a picture of the car before the body kit: With the SubtleZ kit, I have about 1.5" clearance up front and 1" in the rear. With the extra clearance available, I lowered the car 1" up front and 1/2" in the rear. The 275 could be made to work on a 10" wheel if you use the correct combination of wheel diameter, backspace and spring. A 17x10" wheel with 5.5" backspace combined with a 8 inch coilover will allow the tire to fit inside the wheel well with the SubtleZ flares. The key is to get the spring perch above the widest part of the tire. For now, the 245/45/16 tires fit in such a way that I can lower the car onto the bump stops without fear of the tires rubbing.

My car has the SubtleZ fenders and quarter panels. The hood and front air dam started life as the SubtleZ pieces, but I modified them just a bit. The tires on the car are 245/45/16 Hoosiers mounted on 16x8 wheels with a 5" backspace. As you can see, I have room for wider tires. I'm wanting to try some 275/35/15.

Great write-up!!! I think that you give the wrong length for your driveshaft. Mine is 19.25 from center to center, and you quote yours as 28 1/4. But still, great write-up.

By the X in the main hoop, I meant where the horizontal and diagonal intersect. The other X is the low one behind your drive shaft tunnel. But again, I will not push my ideas as right and yours as wrong like some on other sites seem so apt to do. And yes, there are some very knowledgable guys over there. Unfortunately, you have to wade through the flames to get an answer to any question.

Jon, I watched in horror as the guys over there "critiqued your work." That why I only lurk there. I have a question though: Why didn't you route your new bar going forward from one of the existing X's (The one in the main hoop or the one that ties you strut towers to the main hoop. I don't mean to be a critic. I think you are doing a great job. Dan

Pete, It was great meeting you. I didn't realize while we were talking that you were a member of HybridZ or that you were so far from home. I have some pictures of the tube chassis in my album on this site. Justin, Thanks for the compliments. It feels good to get some compliments on the car now that it is back together. The week in Daytona was the first outing with the car since I wrecked it at the 2004 Bay Bottom Crawl. In that time, it went from being wrecked(and ugly), to a car in a perpetual state of body work (and ugly), to finally something I can take pride in. There were many other beautiful Z cars in Daytona and an equal number of great people. Wherever the event is held next year, I have to make the trip. Dan

It was indeed great to meet and hang out with you and the other HybridZ members at the convention. I hope to do it again soon.

I just got my CD with the photos from Daytona. There are ~1200 great images. Here are a few of my favorites: These photos and the other 1200 photos from the convention are available on CD from Steve Rossini at http://http://www.highlanddesignstudio.com/...on07-home.html

bjhines, I wasn't offended, just surprised. Why do you say that it is necessary to go with rear steer? Achieving 100% Ackerman is not one of my goals. There are many options as far as uprights that will work with a front steer set-up.

bjhines, "If you want a different car, buy a different car." I'm sorry, but that is not the HybridZ way. I look at my Z as a blank slate upon which I can spew my wildest ideas (limited of couse by time and money). I know that I am not alone in this sentiment. There are some aspects of the stock front suspension that can be improved by converting to a SLA type front suspension. Mainly, camber gain can be greatly improved. His stated purpose for the car does suggest that a strut suspension based on the existing components will suffice. However, he is already in the process of building a tube chassis, so many of the constraints of the original chassis do not apply. I, on the other hand will probably pursue building an SLA front suspension. I already have my tube chassis complete, and it would be a simple task to add mounting points for upper control arms. My lower control arms are currently stock length (but utilize sperical bearings). My idea is to lengthen the lower control arms by two inches. At the same time I would increase the backspace of the front wheels by the same two inches. For an upright there are several options: First, I could cut off a strut housing and add provisions for an upper ball joint. I dont know if this option will provide an acceptable KPI. Another option is to acquire a front spindle set-up from another car (perhaps a C4 vette). This option is attractive because the spindle could be purchased complete with five lug hubs and big brakes. Whichever upright I end up with, it will be necessary to make some custom upper control arms. The same is true for the outer tie rod ends. The stock ones will nt be long enough. These would be constructed by sourcing the parts available through Coleman racing, Afcoracing and others. Regardless, on HybridZ I rarely expect to hear, "If you want a different car, buy a different car." For better or for worse, that is not the way we operate. Dan McGrath

Jon this all got started because boostedh23a1 is building a tube chassis similar to mine and has some strut questions. He was asked why he was going to the trouble of building a tube chassis front end but still keeping the strut suspension. As part of my reply, I posed the following challenge: Why don't we (the members of HybridZ) undertake the design of a front suspension that utilizes the factory front frame rails. We have several members on the forum with some expertise in this area and several like myself who wish to know more. As a start, I propose that the front frame dimensions (just the frame rails not the strut towers), front crossmember, and rack be retained (to the inner tie rod only). By holding a few things constant, we can reduce the number of variables in the design. The design should use upper and lower control arms and a readily available spindle assembly. Things that should be considered are bumpsteer, roll center, camber gain, scrub radius, etc... Is anyone interested in playing? Who has suspension design software to try out various proposals? I posed it as both an exercise with hopes of producing a real product. Call me weird but it sounds like fun. The original thread is here: http://forums.hybridz.org/showthread.php?p=818359#post818359

I'm sorry but "Milliken & Milliken ". "Hot 12" slicks" is a start. Be more specific. Provide us with a tire from Hoosier or Goodyear. Do you want to build the car around a 15", 16", 17" or 18" wheel? Do you want to minimize scrub radius or minimize KPI? What overall track width do you want? I think it would be cool to try and maximize the length of the control arms and design around wheels with a large back space.