blueovalz

That's my thinking. I love the way my SX handles, but I also love the way the Z handles. The added number of rubber bushings in back makes me wonder about extra movement under high torque.

Is there any reason you couldn't break the engine in in "steps"? My understanding on break-in is total time at a specific RPM range. Breaking it down into several steps: First one say a minute, cool down, next one 2 or 3 minutes, cool down, and then run 10-15 minutes, all steps at a decent "break-in" RPM.

I cannot verify the numbers, but it was "stated' in some string I found on the Megasquirt forum here at HybridZ that the 42mm ITB should be able to support just near 400hp. Just as a matter of note, this diameter is a minimal size, and sets velocity through the ITB at the upper end of "acceptable" (according to what I've read about ITBs and manifold fabrication for EFI applications). The Weber products are pretty expensive, and there are cheaper ways to fabricate a rudimentary EFI set-up that should run well using only timing and TPS inputs.

I would think that with alignment perfectly set at zero camber and toe, there would be no difference in drag. Introduce any changes to this and the drag increases for straight line motion. One comment I'd like to add to this query is the contact patch. For a given weight on the tire, and the pressure in that tire, the contact patch area will be the same for a 185 wide tire as it will be for a 315 wide tire. The difference between the two will be the shape of the contact patch. The 185 will have one longer (front to back) and narrower patch than the 315's short (front to back), but wide pattern.

I fabricated the spacers and finally fitted the bearing retainers onto the CA as they would be in a final installation, and then compared it to a CA with the OEM rubber bushing.

Thought I'd highlight the differences between the early and late Z control arms. I do not know when the change was made, but these changes became very apparent when I was modifying these arms for the spherical bearing conversion. Edit 12/20/06 I found another difference between the 240 and the 280 control arms today as I was modifying them for spherical bearings at the inner bushing location. The difference was the thickness of the steel pivot tube that runs through both front and rear inner bushings. The OD of this tube is the same for all models 25mm (~1”). The differences lie in the ID of the tube. The 280 tubes have an ID of 16mm, while the 240 tubes have an ID of 19mm. My first shot at this modification was to drive ¾” studs into the tube, which worked great for the 240 arms. But the 280 arms require something smaller such as a 5/8” stud, which is too small for my requirements. So I instead turned the 3/4" studs down to 16mm (~5/8") for the portion of the stud that was pressed into the smaller ID pivot tubes. Anyway, thought I’d pass this on.

This is exactly what I thought. I've done this, but always added a little resin catalyst when I did it. Now I know that this resin catalyst is unecessary, and that the filler catalyst will suffice.

It's been so long since I've fooled with the electrical system, but it sounds like the original problem was simply a bad electrical ground on the dim headlight. Anyway, other than that, I'd make sure you've got the correct wires spliced to the correct wires. When I did mine, I used a voltmeter to verify the high and low, and ground wire prior to any splicing, and I seem to remember that it was not an "intuitive" arrangement.

What is the difference between these, and any other 5 hole slotted aluminum wheel seen on the older era Zs? The point of my question is you can by "Shelby American" wheels, but they have nothing to do with the wheels on the original Shelbys, so is there any special importance for these "Bob Sharp Racing" wheels?

So no extra catalyst (hardener) is needed when doing this?

I did this at one time. If I remember correctly, it was a very small indentation or amount of grinding to get this to fit.

I believe the general consensus is that the ZXT (CV-jointed) half-shafts are more durable than the N/A (U-jointed) half-shafts.

What is the length difference? I ask because this added length would decrease the operation angles for the U-joints, which is a good thing (aside from the hassle of fabricating a longer driveshaft).

My take on this is that there is no less, and no more torque applied to the front 4 bolts than a typical long nose differential IF it is mounted solidly at the differential. In essense, both mounting points are then the same, it's just that the means of getting there is different. Important though, is whether the mounts have soft bushings in it, or if this differential mount is solid. A solid mount levers out to the 4 bolts (just as a long nose differential casing would do), which reduces the torque at the 4 bolts (much like a cheater pipe requires less force to spin something verses a short bar). A soft mounting, on the other hand, will not lever out to the 4 bolts and may instead try to twist at the bubber bushings and at a point centered between the two bolts on each side. It would be nice if the R230 had multiple mounting holes on the front (on each side) verses the single hole on each side. The additional vertical bar in the above photo (Alexideways) would address this issue.

These are 3/4". I wanted to use the same size as was on the outboard ends. The 3/4" stud in the last photo (on the previous page) is simply a 3/4" grade 8 bolt with the head cut off and spot welded into the CA pivot tube. With the proper spacers, I should be able to bolt all of this together in a couple of hours. The key is getting the spacing down correctly so that I don't wear the bearings out. As it sets, the bearing retainers have a .0005 interference fit, and a light press seats them easily. This old photo shows my initial goal of using a rod end (bad idea), but now I see that the monoball assembly is definitely the way to go.

It's good to see this project coming to an end successfully Jon, and I think there has been more advancements in sperical bearing assembly for the Z rear control arms on this single string than from any other source. In regards to the monoball source, I bought 8 of these 3/4" bearings, with teflon liners, from a guy on Ebay, and they were in such good shape (description said "slightly used"), I ordered 8 more from him. Anyway, these are the bearings (3/4" though) I'm using. Today (funny how both our projects, on the same subject, are coming together at the same time) the machinist called me and told me my bearing holders were ready. These holders are very similar to the ones you purchased, only with a slightly different direction toward installation. I only had one side done, but he has the numbers in the CNC machine now, and can do more at a cheaper price. Anyway, on the the specifics. My goal was to bolt the monoball assembly into the existing Z saddles and caps, thus requiring only modifications to the CA as far as fabrication at home goes. The bearing retainers I recieved today take a few taps with the hammer to push them into the saddles and for the caps to be set in place. The machinist turned the outer diameter (saddle portion) about 2 thousanths big and I told him to leave it that way until I test fit it. As it currently sits, I have about .070" gap between the two saddle pieces (saddle and cap) that hold this retainer. I figure I'll simply stick a shim between the two, and tighten them down instead of risking a loose fit with the OD turned down any smaller. First photo is the assembly thrown together. I need spacers made for both sides of the monoball, and this will come next week, but until then, this is roughly what the retainer assembly, on the arm, looks like inside the transverse link and cap: This shows the other side of the same assembly with the front retainer and sperical bearing. The front one is longer than the rear one. To retain these bearings I had a groove cut for a clip, but I was concerned that the material around the bearing was too thin for a groove to be cut, so I extended the lip to be about 1/2" deep, and then simply had the groove cut into this part, eliminating any weakening of the retainer with the groove cut inside next to the bearing. With this, I will thus need a spacer between the clip and the bearing. Below is the transverse link and cap from the end view. Notice the .070" gap between the two pieces. The retainer has a perfect fit. Lastly is the CA showing the 3/4" stud extending out of the pivot tube (this work was done 3 years ago. So this is an indication of how long I've been thinking about this. It took Jon to get me of my a$$ to finish it though. Thanks Jon!!!

This does not surprise me in the least. The frame rails are simple boxed sheet metal structures NOT designed to resist being crushed under a bolt going through the middle of the rail. Even 1/8" steel box of this dimension would have deformed some amount (albeit a small amount).

Jon, earlier in this string you mentioned that the monoballs themselves were not a "tight" fit in the housings. This brings up two things: 1) have you noticed any difference in this since the welding is finished 2) If they are still not tight, consider locktight on the outside race. I talked to a builder that had done this very successfully, and simply uses a heatgun to remove them when necessary.

I finished my jig, and the other rear CA modification. I built the jig around an OEM CA, and then used it to ensure the modified CA was exactly like the OEM CA in regards to placement of the critical components. One thing to note here is the difference in rigidity of the OEM arm verses the modified arm. Without actual measurement of deflection angle, I compared how much deflection (in angle) between the inner and outer axis' of the CA using a 3 foot long torque arm. I found that the modified arm was over twice as stiff, and less likely to permanently deform than the OEM arm. I attribute this to the solid plate at the end of the two main structural members of the arm. The OEM arm allowed the two members to move in relationship to each other. Now, with that said, the spindle pin would prevent this movement in an OEM arm, so the advantage I see here is that this plate is reducing any attempt to twist at the Heim joints, thus reducing the shear loading on the joints themselves. It was quite a difference between the two arms. The jig by itself (very simple and took about 2 hours to build): The cut CA partially mounted in the jig awaiting the end plate with Heim fittings: The final pieces fitted together in the jig, but not yet welded together:

If you've only collapsed the top and bottom (bowed them inward) of the frame rails, then these weld-on plates may get you back on your feet. If you've collapsed the sides, then you'll lose some tension and compression rigidity. It appears that this "weld-on plates" method has been successful, but I don't like it. If I were to do this myself, I would also weld some bolt tubes onto one of the plates that would extend through the entire height of the frame rail to the opposite plate. These tubes would then prevent any collapsing of the rail as well as distribute all forces on the assembly to both plates (and hence the top and bottom of the frame rail).

I thought of that as well. Back in the 80's there was a similar pan that covered the bottom of the OEM intake made by Ford for the 351W.

Well David K, it has been a LONG time. How's that Y40 install coming along?

Jon, What size are your monoballs (yes, I here the snickering already).

Interesting observation on the thickness of the steel in this area. It validates the importance of designed strength in this area of the car. What I was refering to on the saddle thickness was to effectively increase the gauge of the material. I thought the saddle caps were about .060 material, and that by cutting some pices that mimicked the side view profile of these caps, you could then weld these thicker pieces on either side of the caps, and even some along the top curved part of the caps ("top" means on the top curve of the caps while mounted to the upsidedown car). An issue is that you will need to address is any fore and aft movement of these housings inside the saddles (provided you are not welding these in). The OEM bushings had lips extending out and around the edges of the saddles, but your steel housings do not, and should not, until you know that the spacing of the bearings, in a fully assembled piece, are in their correct location relative to each other and to the body. The disadvange of welding is that to remove the CA, you will need to unfasten the upright for that CA so that the CA can be pulled rearward far enough drop it out of the front housing. Thinking out loud here; You could slot (just slightly, and if you do your homework right, very little) the holes of the upper portion of the uprights so that once the "close" assembly is fully fastened together, you could then bolt the uprights into position, and if this process is done carefully, would allow the slotted holes to compensate for any minor (but extremely critical) errors in the exact spacing of the monoball bearings relative to each other, thus eliminating any side preloading of the balls.

Could you cut a large hole (or several smaller holes more ideally located) on the lifter over so that you could attach overlaping aluminum from the bottom as "covers" once the installation is completed?