Geo Metro powered Middy - Build Log

[Talon]

As I look for examples, I realize that what I was looking at was twin-stick cable shifters for transfer cases. Scratch that, sorry.

TALON §

[Talon]

It has been a few weeks since I last posted, so I figure I oughta catch up a bit. I now have the surround for the engine compartment actually surrounding the engine. I also have the motor mounts sorted out and installed, so the engine/trans is hanging now. The Geo engine has three mounts, front engine, front trans and rear transmission. Of course my engine didn't have any of them with it. I purchased the front engine mount and fabricated a bracket for it. I fabricated the front transmission mount and the bracket. And, last but not least, I modified the rear trans mount to take a polyurethane bushing and fabricated the bracket. This gives us three points of support and hopefully will be stout enough to handle all those raging horses.

The front transmission mount I am not really happy with, so I may rebuild it, or plate the sides when I clean up and paint the engine cradle later. It is strong in one plane, but I'm not sure about the other, or need for strength the other way. We'll see.

I have decided to go with McPherson struts in the rear, with single lower A-arms, and I now have the parts, mostly. I ordered Heim joints and screw-in lower ball joints for the lower A-arms and decided to order weld-in bungs for the heims as well, remembering back to tapping the front arms, this sounded like a good idea. Turns out that my local steel shop doesn't carry the right size tube for the bungs. I haven't decided if I should order the expensive tube, or grind flats on the bungs and use square tube instead of round. I'll probably go with the expensive round tube and hope they can get it to me before Christmas.

By using the McPherson struts from my 1997 Ford Aspire donor, I get disc brakes and matching wheel pattern from the front spindles. I get a little too much height though, and springs that are way stiffer than the fronts, and more weight than I really wanted. (the two strut assemblies weigh more that the engine/transmission) I may end up doing upper A-arms and coil-overs for the rear as well, we'll see once I start figuring out how to mount the tops of the struts, it might be easier. They will stick up above the existing engine frame by about a foot and a half, so I'll need to do a pyramid structure to hold the tops. This will be in the rear though, so visibility shouldn't be a problem.

Anyway, that's where I'm at. More later. Pix below.

TALON §

[freebeard]

Thanks for the update.

By using the McPherson struts [snip] so I'll need to do a pyramid structure to hold the tops.

Make the A-arms as rocker arms and use horizontal (lateral or longitudinal) coil-overs.

[Talon]

I have thought about that. If I end up doing an upper A-arm instead of the strut, I'll attach the coil-over to the top A-arm (instead of the lower as in the front) and do something for a rocker. Coil-overs will probably be vertical behind the engine if I go that way. Horizontal coil-overs are just too sexy though. . .

TALON §

[JackMcCornack]

Originally Posted by Talon

Making a cable shifter may be kinda tricky. The shaft is pointing out to the rear, which is what it should do in the original car, and requires both push/pull and twist it appears. In my rear engine setup, the shaft will be pointing towards the back bumper, so I'll need something to completely reverse the inputs and put them on the other side of the engine and forward around 3-4 feet, while hopefully keeping something that still resembles and H pattern. I'm gonna have to think on that one. . . any ideas?

Man have I got good news for you! You can "completely reverse the inputs" by using the stock shifter mechanism (the shift lever, base, and pushrod) and turning it around so the pushrod points backward. You'll have to lengthen the pushrod by cutting it and welding a tubing sleeve to it, and you have to make an upright "U" that welds to the end of the pushrod (with holes in the legs to bolt to the sleeve on the end of the shift rod that sticks out of the transmission) and the U has to be tall enough that the pushrod can go under the engine, but it works, and keeps the same H pattern as the original.

Here's the deal. When you push the shift lever to the right, it rotates the pushrod (looking at the trans from the rear) clockwise, and that doesn't change, whether the engine is forward of the shift lever or rearward. When you push the shift lever forward, it moves the pushrod backward (there's a pivot on the shift lever and the pushrod connects to the bottom of the shift lever). When the shift lever is mounted behind the engine (as in a Metro), moving the pushrod backward pulls the shift rod backward. When the engine is mounted behind the shift lever (as with your and my middies) the pushrod pushes instead of pulls, but sonofagun, when the push-input comes from the front, it pushes the shift rod backward. Ta dah, pattern unchanged, and no cables to mess with.

The brace rod will be on the wrong side of the pushrod, and if you want to use the original shifter bracing you'll have to pass one of the rods under the other, and you'll probably have to do some bending to snake the pushrod through the chassis, and...dang, there goes the bell. The details will be left as an exercise for the student.

[Talon]

Cool. I had about given up on rods, due to the fact that a shift shaft would have to slip in between the bell housing and the engine, and any twisting action on a non-linear shaft would create a "swing" that I'm not sure would fit in between the bell and the oil pan. Also, I am a single seat. I want the shifter to be on the right, not between my knees, so I'll need about 18 inches of off-set from the location on the trans that the shifter enters. I think I can handle the offset with a pivoting shaft for the in/out and a cross-over rod for the twist part. I would much rather have rods than cables though. I am going to have to do some coat-hanger design work. Maybe the "swing" will be small enough to fit in the space available, maybe I can bring it clear under the bell housing, maybe I can do the off-set shaft in the rear and bring the shift-shaft around the right of the engine. Cables are 50-60 bucks apiece, so I definitely want to fully explore rods first. Rods just feel better too, if they are done right.

On another note, I did get the expensive DOM tubing to fit my bungs for the rear lower A-arms. Kinda irritating though, I gotta go out of town this week for work, so I won't get much done. Having parts waiting for me, but obligations getting in the way, is a downer.

Thanks for the information Jack, it is appreciated. Now I just need to get some garage time. . .

TALON §

[Talon]

It has been a while since I have posted, not a lot of work done on the little car during that time, just head scratching and doodling. (I have gotten 14 cords of wood cut, bucked up , split and stacked for the stove though.) It is funny how you either have time or money, not both at the same time. The triple digit work weeks I have been having sure cut into the garage time.

I have sorted out the shifter issue I think. I built the linkages and it seems to work fine, but I didn't get any pictures of that system. I'll show you later when I remember to get pistures.

Here's what I have gotten done on the car. First, I determined two things: that the width of the engine cage was too wide for A-Arms and that the McPherson struts are too heavy. A-arms would either be about 4 inches long, or the rear track would have to be way too wide, like 7 foot. The struts are very heavy, the set out of my donor Ford Aspire, hubs/struts, weigh almost as much as the engine. That ain't a good use of weight.

Anyway, to make it work, I decided to slice the ends off of the engine cage and give myself enough space for a-arms, so that is what I am doing. Slicing about 10 inches off of the ends gives me enough room on the ends of the engine, and room for a-arms that are 13.5 inches long, enough for good suspension travel. I will sort out coil-over setup yet, probably horizontal. Upper a-arm is set up with heims at all three points. I used the DOM tubing and weld-in bungs this time, rather than threading the tube like I did on the front a-arms. I only made one so far, but I got the jig, so the second upper rear a-arm will be fairly quick the build.

I took a lot of persuading to get the hubs to seperate from the half-shafts. That was not easy, but I won in the end. Once seperated, I needed to modify the hub/bearing carrier a bit to fit my screw-in lower ball joints. A simple bracket was built for the top of the hub.

Next it is on to the lower rear a-arm, then repeat the steps on the other side.

It is getting to be fall, so hopefully I'll have more time to work on the little car. . .

TALON

[Talon]

Here's where I am as of now:

I have essentially finished the rear suspension for both sides, full-welded the engine cradle, plugged any open tube ends, ground the welds that will be on the outside of the cradle where bodywork may touch. I also raised the engine in the cradle about 4 inches for clearance.

The rear suspension came together rather nicely I believe, I ended up going with a pyramid for the upper shock mount though, and here's why, when I did the calculations and drew the lines for a rocker arm type upper a-arm, the structure would have been within an inch or so of the same height. I then looked at a push rod and separate rocker setup which would have lowered the top, but add complexity. In the end, simple and stout wins out. I may revisit this later though. If you look at the picture of the rear suspension, you will see the "extra" shaft needed to lock the steering part of the hub. Remember, this is a front hub from my donor Ford Aspire, so in it's natural habitat, it steered as well, which wouldn't be very good on the rear axle.

The overall width of the rear track, from wheel mounting flange to wheel mounting flange, comes in at 6 foot 2 inches. The wheel base, front to rear, comes in at 6 foot 4 inches. Almost square. So now I can work on the front steering, as I know the wheelbase and width and can calculate the ackerman angle correctly.

I needed to raise the engine in it's cradle as well. when I got the first side of the rear suspension sorted out and could look at things clearly, the rear axle shafts would have actually dropped a bit going from the hubs to the transaxle, and the oil pan would have had about 4 inches of ground clearance. This might have been OK on a track, but not in the real world, so raising the engine in the cradle (about 4 inches) I now have just a bit of rise from the hubs to the transaxle at ride height, and plenty of clearance for the engine. Currently, the engine cradle is the lowest part, only the tip of the oil drain plug goes below. This puts the top of the engine a little less than 2 feet above the bottom of the cradle, and the bottom of the cradle should be 6 inches from the ground, so rear deck height can be as low as 30 inches. This will also put the rear deck height about shoulder level for the driver.

Next up is the steering and pedals. The steering should be pretty straight forward now that I know the wheelbase/rear track width. The pedals should be as well. I am going the use a hydraulic clutch, and brakes, so routing lines becomes as easy as running tubing. The throttle will be a cable, I just need to find a long one. Shifter is sorted. Very soon, I will need to do a thorough cleaning of the garage, bolt the two halves together, take apart my workbench and put the thing on jack stands, in preparation for engine work.

My engine came from a running car, but has been out of the car for several years, so it will need to come apart for inspection and rebuilt. I am still in need of a cam sprocket, as mine has been spun. (pressed steel) Anyone have one I can buy?

As an aside, has anyone notice this site being extremely slow lately? Or is it just me. . .

TALON §

[Talon]

I haven't posted much lately. Ow well, progress goes on however. I have attached the two parts, engine cradle and passenger compartment, together and made some quick and dirty stands for the car and put it on the stands. I have the steering done. The suspension is on three corners now, I need to take apart my build bench to make room for the fourth corner, then I'll put it on the ground to look at and bounce on it to test the suspension. I need to make sure that my ride height is where I want it.

The steering wasn't easy. I am using a Pinto/MustangII rack because it is the correct width with the inner tie rod ends falling on the line between the inner mounts on the upper and lower A-Arms. The problem is that the rack has the input shaft to the left, aiming outward to clear the engine,(which isn't there on mine), and I am using a center steering column. That is a lot of directional change. I found a Ford Ranger steering shaft that had a double U-joint and I am using the single u-joint from my donor column as well. it is kinda Rube Goldberg, and both joints are at max flex, but it seems to work smooth and very light now. I had to extend the tie rods about 11 inches on each side to reach the steering arms on the knuckles.

Wheel base is exactly 7 foot, and track width is 6foot 6 inches from tire centerline to tire centerline. The tires are the furthest thing forward and aft, they stick out past the frame in all directions actually.

I found a cam pulley to replace to wallowed out one that was on the engine. The end of the cam has some wear as well from the undertightened bolt. That all happened before I got the engine, but it must have been exciting for a few minutes. Before too long I will need to tear the engine down to see what it needs. I'm not too concerned about that though, a full rebuild kit including pistons and rings, water pump and oil pump can be had for around $250. Might need a cam too though.

Seat belts are in. Seat mounting is in. Steering column support is in. I am working on the shifter now. I am going to mount a rod end for the lower shifter mount and have a tube and bracket to mount the gear linkage shaft. It is very hard to get a picture of the whole gear shift linkage setup, that will have to wait until I take it all back apart to paint/polish before final assembly.

Pedals are next, if I can keep putting off taking the build bench apart. If not, I'll put it on the ground first.

TALON §

[Talon]

As I gander back at this, there are a couple thing I should point out that changed along the way. The upper rear hub bracket changed. It was straight, but interfered with the inside of the tire, so I rebuilt them with an offset to clear to tire. I also raised the engine/trans in it's cradle about 5 inches. Originally the drive shafts were actually dropping from the hub to the trans. This also gives me more rear ground clearance. The very tip of the drain plug is now the only thing that extends below the frame.

I think I have the correct tilt forward on the engine, but I am guessing, as I didn't have a full donor car for the engine, just the engine itself, I couldn't make any measurements. Anyone know if I am close?

TALON §