rx1900
1981 X1/9
Hi folks. As the title suggests, the following posts will document my Fiat X1/9 coilover build.
For more background info, please read all the threads in my post titled "strut info needed", but in essence I will be using any VW Rabbit strut insert in a modified VW strut housing and your choice of any 2 1/2" racing spring.
I have done this without a lathe or milling machine. A bit of welding is required, but nothing too difficult.
If you wish to perform this yourself, please be careful. If you are uncomfortable with any of the steps or consider anything unsafe, then please do not attempt.
Sparks will be be flying and it will be a bit noisy so PLEASE:
1) For sure wear safety goggles and hearing protection. Wear long
sleeves, long pants, decent footwear, and thick leather gloves.
Things will be getting hot.
2) Clear the area of all flammables. Yes, move that container of
lawnmower gas !
3) Do not (like I did) dump most of the contents of an old strut
all over your pants. Old Fiat shock oil really stinks !
I actually found the whole exersize rather enjoyable and challenging. I did it because none of the other available options out there met my abilities, needs, and budget. It is very satisfying to create something with your own hands. I'm sure that most of you out there with limited skills - like myself - can do this.
So let's get started....
First of all, you will need some type of power mitre saw - you know the type for cutting wood 2 x 4s. Like the one pictured below. I'm sure most of you have one. If not, buy one (they are cheap - less than $100), borrow one, or rent one. Mine is an old Delta 10". Buy a 10" (or whatever size you saw is) metal cut-off disc. Like $5 at Home Depot. Remember when changing blades the centre bolt is usually left-hand thread. I know, you have probably never changed the blade in it !
Start by hacking off the protuding bits on the VW strut housing. The brake line holders can be removed first by knocking back and forth with a hammer. Then with a series of cuts on the saw cut off as much of the spring perch as possible as shown:
Then slice off one side of the mounting bracket with a lengthwise cut as shown:
Then cut off the other side of the bracket. From the inside as shown. Cut as close to the strut tube as possible:
An action shot:
Now set the VW strut housing aside and grab the old Fiat housing or strut. If using a sealed strut, first drill a hole in it and drain the fluid. Extend the shock fully so you won't be cutting through the main shaft.
First put some bolts, nuts, and washers into the mounting holes as shown and tighten till you just start to spread it. This will stabilize that part of the bracket during the whole proccess. I initially didn't do this and the bracket spacing changed during later prying. Don't make my mistake.
Now slice through the whole tube about 1/8" above the weld as shown at the bottom part of the sleeve as shown:
Then make a slice lengthwise through the back of the sleeve as shown:
With a bit of tapping and prying the sleeve will now come off:
Now for the really clever bit. We now have to remove the sleeve from the VW strut housing without damaging the housing. Hmmm...
Take a scrap of plywood or MDF and position the wheels as shown. Make sure the one edge is straight and screw on 2 of the wheels up to the edge. Draw 2 lines as shown. The 1 line should be exactly parallel to the edge 2 3/8" from the edge. The other 2 lines should be about 4 1/4" apart. Screw all the wheels on.
Now look at your mitre saw. Somewhere near the pivot point you should find a bolt that adjusts and limits the downwards travel of the blade. Screw it all the way in and see how far your blade now comes down. Now you will probably need to install a smaller blade. In my case I had to use a 4" blade for this to work. Blades are available in lots of sizes. Hint: buy the thickest blade you can find. In fact, installing 2 blades together will form a thick blade and make the next part go faster.
Now place the board with wheels up under the saw with the VW tube on the rollers. Play with the adjustment screw and blade sizes until you reach a combination where the blade CANNOT touch the main part of the tube. You should be starting to get the idea by now.
Adjust the screw so that the blade will just start to touch the sleeve.
Now you will see that you have just turned your mitre saw into a backwards lathe. Well sort-of. Okay not really. But hey, it works !
Now start by making 2 shallow cuts on the sleeve about 1/4" inwards of the welds. Bring down the blade and then simply rotate the tube on the rollers to cut all the way around. Then adjust the screw to make the cut deeper. Use the main part of the tube as a reference and adjust so that the blade is just touching the tube. Make your final pass on the 2 cuts and the sleeve should then be able to be pried open and removed fron the tube.
Now go back and in a series of cuts, rotations, and sliding back and forth, remove the remnants of welds until the tube is smooth and clean. But for now, do NOT touch the remnants of the spring perch.
Pretty cool, eh !
If you make any boo-boos and cut into the tube in error, just fill in with weld and re-grind.
Now you can trial fit the Fiat bracket/sleeve onto the now clean VW housing. Unfortunately the Fiat strut tube is about 45mm O.D., while the VW strut tube is about 48mm O.D. at that point. This is why we slit the back of the Fiat sleeve. Pry open the Fiat sleeve (make sure those bolts are still there - they prevent that part of the bracket from bending while you are prying) until it slides over the the VW tube. This is just a trial fit for fun, remove the sleeve for now.
Next we will work on fitting the coilover sleeeve. Unfortunately the VW sleeve is expanded at the top couple of inches to 50mm (the rest of the tube is 48mm). Thus we have to use a coilover sleeve with an I.D. of at least 50mm. The closest one I could find was 50.5mm I.D.. But in fact the inside of the sleeve was not constantly 50.5mm throughout its length. This is because of its intended use on a shock that requires circlips to hold it on.
Put the VW tube back in the " X lathe" and "turn down" the remnants of the spring perch so that the sleeve (use the 5" sleeve in front 7" sleeve in rear) is a snug fit over it. This will locate the sleeve and keep it from rattling around. Now I know the sleeve just locates the spring and not the suspension and it really doesn't matter if the sleeve is loose. Just a matter of pride mostly. Yes, duct tape would serve the same purpose, but really...
Then lay down 4 lengthwise beads of weld near the top of the tube. To support and locate the top of the sleeve. "Turn down" the welds so that the sleeve is again a snug fit. This will keep the top of the sleeve from rattling about.
Now slide the Fiat bracket/sleeve back onto the tube and weld into place. A couple of notes here:
The sleeve will be a little distorted from all the prying so clamp it down in a vise to get full contact before welding.
Now in what position you weld the bracket back on is a big decision. I think you want to weld it on HIGHER UP than original. Two reasons here. First, the VW tube is about 1/2" longer than than the Fiat tube, so welding the bracket higher up will correct this. Secondly, and this is hard to explain, if you wish to lower the car, welding the bracket higher still will lower the car without eating into suspension travel. So all things considered, you are probably best to RAISE the bracket as much as possible. Luckily, you can raise the bracket about 1" before the bottom of the strut housing interferes with the lower ball joint. Now I hesitate to give you an exact measurement (I'm sure there is some variation between years of X1/9s and various VW and Fiat struts) here, BUT in my case I found a distance of 6 & 7/8" from the bottom of the VW tube to the top of the ring of the Fiat sleeve to be perfect. Maybe tack it on at this distance and trial fit it on your car to be sure.
Now this weld is fairly critical to the structural integrity of the unit, so - unless you are are a skilled welder - please take it to someone who is !! I must admit this is the only part of the project I had someone else do. Thanks to Rick for the ace welding. If you blow through when welding or cause big bumps on the inside of the tube, you will be fairly screwed. Most 42mm inserts are a tight fit and if you cause protusions on the inside of the tube the insert will no longer slide in !! You would then have to get inside there with a grinding stone to correct.
Weld the sleeve everywhere - top, bottom, and up both sides of the back slit.
Luckily for us the Fiat sleeve has a large lip on the top. More than enough to support the coilover sleeve. You may want to lay down a little blob of weld at the top of the Fiat sleeve somewhere and file a corresponding notch in the coilover sleeve. This will prevent the coilover sleeve from rotating when you later go to adjust the bottom perch to change the ride height. Look carefully at some of the later pictures and you can see it.
So after welding the bracket, clean it up and apply your favourite primer and paint.
When dry, slide the coilover sleeve on - there is no need to secure it, spring tension will keep it in place. Spin on the jamb nut and the lower spring perch/nut. Run a neat bead of silicone seal around the top of the coilover sleeve to prevent water from entering though the small gap there. Slide the shock insert with its spacers and secure with the top nut.
Congratulations, you are now done for now. Grab a beer and stand back and admire your handiwork !!!
Up to now, of course, we have been talking about the front struts. The rears are pretty much the same, with a couple of differences. We will be using VW front strut housings again, but will be using Fiat REAR sleeve/brackets. And, very important, after removing the centre portion of the VW sleeve, DO NOT remove the upper portion of the remaining weld. We will just be "turning it down" a bit to the I.D. of the coilover sleeve. Luckily the VW sleeve is longer than the Fiat sleeve and thus the remaining weld is in the perfect location to locate the lower portion of the coilover sleeve. We will again be "turning down" the remnants of the spring perch to locate the upper end of the coilover sleeve.
I think in the rear we can raise the bracket/sleeve about 1/4" before the shock interferes with the driveshaft. My X currently has no driveshafts in it so I am not sure. Please check for yourself before welding.
So I guess we are done for now. I am still working on the upper spring perches and mounts. I have some nifty ideas for there too. But that is for another day. Stay tuned !!
My next post will be a list of parts and supplies needed to do today's thread.
If you have any comments or questions, please post. If you find a better way, please let us know.
Please note I have nothing to sell here. In my next post I will tell you where to get all needed parts and supplies. Where I live, all purchases or imports are subject to a 13 % tax, so I'm sure most of you can buy everything cheaper than I could.
If you need any advise, just ask. If anyone local wants to borrow my " X lathe" , no problem.
Good luck, work safely, and have fun.
Cheers, Doug
For more background info, please read all the threads in my post titled "strut info needed", but in essence I will be using any VW Rabbit strut insert in a modified VW strut housing and your choice of any 2 1/2" racing spring.
I have done this without a lathe or milling machine. A bit of welding is required, but nothing too difficult.
If you wish to perform this yourself, please be careful. If you are uncomfortable with any of the steps or consider anything unsafe, then please do not attempt.
Sparks will be be flying and it will be a bit noisy so PLEASE:
1) For sure wear safety goggles and hearing protection. Wear long
sleeves, long pants, decent footwear, and thick leather gloves.
Things will be getting hot.
2) Clear the area of all flammables. Yes, move that container of
lawnmower gas !
3) Do not (like I did) dump most of the contents of an old strut
all over your pants. Old Fiat shock oil really stinks !
I actually found the whole exersize rather enjoyable and challenging. I did it because none of the other available options out there met my abilities, needs, and budget. It is very satisfying to create something with your own hands. I'm sure that most of you out there with limited skills - like myself - can do this.
So let's get started....
First of all, you will need some type of power mitre saw - you know the type for cutting wood 2 x 4s. Like the one pictured below. I'm sure most of you have one. If not, buy one (they are cheap - less than $100), borrow one, or rent one. Mine is an old Delta 10". Buy a 10" (or whatever size you saw is) metal cut-off disc. Like $5 at Home Depot. Remember when changing blades the centre bolt is usually left-hand thread. I know, you have probably never changed the blade in it !
Start by hacking off the protuding bits on the VW strut housing. The brake line holders can be removed first by knocking back and forth with a hammer. Then with a series of cuts on the saw cut off as much of the spring perch as possible as shown:
Then slice off one side of the mounting bracket with a lengthwise cut as shown:
Then cut off the other side of the bracket. From the inside as shown. Cut as close to the strut tube as possible:
An action shot:
Now set the VW strut housing aside and grab the old Fiat housing or strut. If using a sealed strut, first drill a hole in it and drain the fluid. Extend the shock fully so you won't be cutting through the main shaft.
First put some bolts, nuts, and washers into the mounting holes as shown and tighten till you just start to spread it. This will stabilize that part of the bracket during the whole proccess. I initially didn't do this and the bracket spacing changed during later prying. Don't make my mistake.
Now slice through the whole tube about 1/8" above the weld as shown at the bottom part of the sleeve as shown:
Then make a slice lengthwise through the back of the sleeve as shown:
With a bit of tapping and prying the sleeve will now come off:
Now for the really clever bit. We now have to remove the sleeve from the VW strut housing without damaging the housing. Hmmm...
Take a scrap of plywood or MDF and position the wheels as shown. Make sure the one edge is straight and screw on 2 of the wheels up to the edge. Draw 2 lines as shown. The 1 line should be exactly parallel to the edge 2 3/8" from the edge. The other 2 lines should be about 4 1/4" apart. Screw all the wheels on.
Now look at your mitre saw. Somewhere near the pivot point you should find a bolt that adjusts and limits the downwards travel of the blade. Screw it all the way in and see how far your blade now comes down. Now you will probably need to install a smaller blade. In my case I had to use a 4" blade for this to work. Blades are available in lots of sizes. Hint: buy the thickest blade you can find. In fact, installing 2 blades together will form a thick blade and make the next part go faster.
Now place the board with wheels up under the saw with the VW tube on the rollers. Play with the adjustment screw and blade sizes until you reach a combination where the blade CANNOT touch the main part of the tube. You should be starting to get the idea by now.
Adjust the screw so that the blade will just start to touch the sleeve.
Now you will see that you have just turned your mitre saw into a backwards lathe. Well sort-of. Okay not really. But hey, it works !
Now start by making 2 shallow cuts on the sleeve about 1/4" inwards of the welds. Bring down the blade and then simply rotate the tube on the rollers to cut all the way around. Then adjust the screw to make the cut deeper. Use the main part of the tube as a reference and adjust so that the blade is just touching the tube. Make your final pass on the 2 cuts and the sleeve should then be able to be pried open and removed fron the tube.
Now go back and in a series of cuts, rotations, and sliding back and forth, remove the remnants of welds until the tube is smooth and clean. But for now, do NOT touch the remnants of the spring perch.
Pretty cool, eh !
If you make any boo-boos and cut into the tube in error, just fill in with weld and re-grind.
Now you can trial fit the Fiat bracket/sleeve onto the now clean VW housing. Unfortunately the Fiat strut tube is about 45mm O.D., while the VW strut tube is about 48mm O.D. at that point. This is why we slit the back of the Fiat sleeve. Pry open the Fiat sleeve (make sure those bolts are still there - they prevent that part of the bracket from bending while you are prying) until it slides over the the VW tube. This is just a trial fit for fun, remove the sleeve for now.
Next we will work on fitting the coilover sleeeve. Unfortunately the VW sleeve is expanded at the top couple of inches to 50mm (the rest of the tube is 48mm). Thus we have to use a coilover sleeve with an I.D. of at least 50mm. The closest one I could find was 50.5mm I.D.. But in fact the inside of the sleeve was not constantly 50.5mm throughout its length. This is because of its intended use on a shock that requires circlips to hold it on.
Put the VW tube back in the " X lathe" and "turn down" the remnants of the spring perch so that the sleeve (use the 5" sleeve in front 7" sleeve in rear) is a snug fit over it. This will locate the sleeve and keep it from rattling around. Now I know the sleeve just locates the spring and not the suspension and it really doesn't matter if the sleeve is loose. Just a matter of pride mostly. Yes, duct tape would serve the same purpose, but really...
Then lay down 4 lengthwise beads of weld near the top of the tube. To support and locate the top of the sleeve. "Turn down" the welds so that the sleeve is again a snug fit. This will keep the top of the sleeve from rattling about.
Now slide the Fiat bracket/sleeve back onto the tube and weld into place. A couple of notes here:
The sleeve will be a little distorted from all the prying so clamp it down in a vise to get full contact before welding.
Now in what position you weld the bracket back on is a big decision. I think you want to weld it on HIGHER UP than original. Two reasons here. First, the VW tube is about 1/2" longer than than the Fiat tube, so welding the bracket higher up will correct this. Secondly, and this is hard to explain, if you wish to lower the car, welding the bracket higher still will lower the car without eating into suspension travel. So all things considered, you are probably best to RAISE the bracket as much as possible. Luckily, you can raise the bracket about 1" before the bottom of the strut housing interferes with the lower ball joint. Now I hesitate to give you an exact measurement (I'm sure there is some variation between years of X1/9s and various VW and Fiat struts) here, BUT in my case I found a distance of 6 & 7/8" from the bottom of the VW tube to the top of the ring of the Fiat sleeve to be perfect. Maybe tack it on at this distance and trial fit it on your car to be sure.
Now this weld is fairly critical to the structural integrity of the unit, so - unless you are are a skilled welder - please take it to someone who is !! I must admit this is the only part of the project I had someone else do. Thanks to Rick for the ace welding. If you blow through when welding or cause big bumps on the inside of the tube, you will be fairly screwed. Most 42mm inserts are a tight fit and if you cause protusions on the inside of the tube the insert will no longer slide in !! You would then have to get inside there with a grinding stone to correct.
Weld the sleeve everywhere - top, bottom, and up both sides of the back slit.
Luckily for us the Fiat sleeve has a large lip on the top. More than enough to support the coilover sleeve. You may want to lay down a little blob of weld at the top of the Fiat sleeve somewhere and file a corresponding notch in the coilover sleeve. This will prevent the coilover sleeve from rotating when you later go to adjust the bottom perch to change the ride height. Look carefully at some of the later pictures and you can see it.
So after welding the bracket, clean it up and apply your favourite primer and paint.
When dry, slide the coilover sleeve on - there is no need to secure it, spring tension will keep it in place. Spin on the jamb nut and the lower spring perch/nut. Run a neat bead of silicone seal around the top of the coilover sleeve to prevent water from entering though the small gap there. Slide the shock insert with its spacers and secure with the top nut.
Congratulations, you are now done for now. Grab a beer and stand back and admire your handiwork !!!
Up to now, of course, we have been talking about the front struts. The rears are pretty much the same, with a couple of differences. We will be using VW front strut housings again, but will be using Fiat REAR sleeve/brackets. And, very important, after removing the centre portion of the VW sleeve, DO NOT remove the upper portion of the remaining weld. We will just be "turning it down" a bit to the I.D. of the coilover sleeve. Luckily the VW sleeve is longer than the Fiat sleeve and thus the remaining weld is in the perfect location to locate the lower portion of the coilover sleeve. We will again be "turning down" the remnants of the spring perch to locate the upper end of the coilover sleeve.
I think in the rear we can raise the bracket/sleeve about 1/4" before the shock interferes with the driveshaft. My X currently has no driveshafts in it so I am not sure. Please check for yourself before welding.
So I guess we are done for now. I am still working on the upper spring perches and mounts. I have some nifty ideas for there too. But that is for another day. Stay tuned !!
My next post will be a list of parts and supplies needed to do today's thread.
If you have any comments or questions, please post. If you find a better way, please let us know.
Please note I have nothing to sell here. In my next post I will tell you where to get all needed parts and supplies. Where I live, all purchases or imports are subject to a 13 % tax, so I'm sure most of you can buy everything cheaper than I could.
If you need any advise, just ask. If anyone local wants to borrow my " X lathe" , no problem.
Good luck, work safely, and have fun.
Cheers, Doug
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