Pat's Ebay Turbo Compound Boost Build
#1181
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I tried it in my car, and I learned it's a great way to end up wadded up in the wall. I am never making another pass in a Miata without the front sway. Other cars I have driven that are straight axle are perfectly safe without a front sway.
It maybe another matter if you had much stiffer suspension in all four corners.
It maybe another matter if you had much stiffer suspension in all four corners.
#1182
If you keep the car straight, you are ok. If you get out of the groove and the car starts to sway, game over. Not really likely to happen in my N/A car, but it was still very unnerving. Your car is much more likely to get out of line because of the power. Consequences are pretty steep.
Besides, I did not see any better gains in 60' by removing it. The only gain you have is weight reduction. The trend is to keep the car from leaning to one side during a hard launch, which the anti roll bars help reduce.
Besides, I did not see any better gains in 60' by removing it. The only gain you have is weight reduction. The trend is to keep the car from leaning to one side during a hard launch, which the anti roll bars help reduce.
#1183
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I will leave the front bar hooked up for now, but will probably try a launch-only (to check 60' time) with the bar unhooked just to see what difference it makes. If no diff, won't try a full pass with it unhooked.
So, an update. I'm going through the rear suspension right now.
I got the rear suspension apart, and removed all the old bushings. They didn't look that bad to be honest. Hopefully the poly are stiffer.
Also removed the hubs and knocked out the wheel bearings from the uprights. Those suckers were IN THERE, what a big pain. I got new hubs/bearings today so installed those. Old hubs looked fine but I've seen the pics/vids of hubs failing so those got replaced. I tired heating the uprights and freezing the bearings to see if that would help installing them. They were a 6 thousandth interference fit when at the same temp! First upright I heated to 250, that one was a big pain to install. Had to hammer it in using an old bearing as a drift to tap the outer race. It was easier than removing the old ones but it didn't just fall in. Second upright I heated to 300, it was about the same, still a pain to install but better than removal went. New seals as well, and c-clips.
Got the A-arms cleaned up, inspected, and installed with all the new parts. I didn't install the springs/dampers yet. Once the control arms and uprights were installed, I put the eccentrics to the middle position, leveled the chassis, and then used a jack to pickup the suspension to ride height, and to 1" compression and checked the camber. At ride height, both rear wheels showed 1* of negative camber. With 1" of compression, both showed about 2* of negative camber. I was able to max the ecentric bolts to get it to 0* camber at ride height, and it goes to about .7-.8 with 1" of compression. I plan to have it sit at ride height, and hopefully only compress an inch or so on launch with stiffer springs.
Now waiting on springs, then it's all back together.
This is prob a dumb question, but on the rear wheel bearings, I torqued the big 32mm nut to 170 ft*lbs. After doing this, both rear wheel hubs are really hard to turn. Is this normal?
So, an update. I'm going through the rear suspension right now.
I got the rear suspension apart, and removed all the old bushings. They didn't look that bad to be honest. Hopefully the poly are stiffer.
Also removed the hubs and knocked out the wheel bearings from the uprights. Those suckers were IN THERE, what a big pain. I got new hubs/bearings today so installed those. Old hubs looked fine but I've seen the pics/vids of hubs failing so those got replaced. I tired heating the uprights and freezing the bearings to see if that would help installing them. They were a 6 thousandth interference fit when at the same temp! First upright I heated to 250, that one was a big pain to install. Had to hammer it in using an old bearing as a drift to tap the outer race. It was easier than removing the old ones but it didn't just fall in. Second upright I heated to 300, it was about the same, still a pain to install but better than removal went. New seals as well, and c-clips.
Got the A-arms cleaned up, inspected, and installed with all the new parts. I didn't install the springs/dampers yet. Once the control arms and uprights were installed, I put the eccentrics to the middle position, leveled the chassis, and then used a jack to pickup the suspension to ride height, and to 1" compression and checked the camber. At ride height, both rear wheels showed 1* of negative camber. With 1" of compression, both showed about 2* of negative camber. I was able to max the ecentric bolts to get it to 0* camber at ride height, and it goes to about .7-.8 with 1" of compression. I plan to have it sit at ride height, and hopefully only compress an inch or so on launch with stiffer springs.
Now waiting on springs, then it's all back together.
This is prob a dumb question, but on the rear wheel bearings, I torqued the big 32mm nut to 170 ft*lbs. After doing this, both rear wheel hubs are really hard to turn. Is this normal?
#1184
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Really hard sounds not right, they turned freely/smoothly before installing the upright in the car right? When you pressed the hub in you supported the back of the inner bearing race or forgot then pushed it back the other way (has happened before..)?
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Yeah they were free as could be before torquing the nuts. I did backup the inner race before pressing the hubs into the bearings. I'm probably gonna just drive it and hope it loosens up after a few miles. I think this could be normal, but my internet searching didn't show me a conclusive yes or no on this.
#1187
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What would I check? If I remove the bearings I might as well replace them, but I'd have to order new ones again. I used new hubs as well, anything I need to check on those? I dunno what to look for. Everything was clean on assembly.
#1188
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FWIW the drivers side, when I install a wheel I can spin it. There is resistance but I could see that being a normal amount of resistance. The passenger side is like 3x stiffer, very hard to turn.
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Only thing I would do for a quick check is loosen then retorque in a couple steps to see how tightens up. If it still feels bad/way worse than the opposite side; it's only a few bucks to replace a bearing/hub vs a failure which is not a ton of fun.
#1192
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I untorqued the nut, that didn't change the tightness at all. So pulled the upright and inspected. Actually found 2 issues. I greased the seal that touches the axle, but only the inside, not the outer part that also touches the axle. That spot was dry and obviously rubbing. I also made sure that seal was bottomed out in the upright to be absolutely certain. But the "big" problem was with the axle. The part that the axle hits the inner race, there was some light rust that was poking up a tiny bit. So probably making the inner race crooked on a tiny scale. I removed the little rust spot, and cleaned/greased it and reassembled and now it feels fine torqued to 170 I can rotate the hub by hand like the drivers side. Actually it now rotates a bit better than the other side.
Thank you folks for confirming there was a problem.
Curly, I have not adjusted the toe yet. You're right about it having a big affect, I gotta try to adjust it still. I was thinking once the car is back on the ground, use the string method and a caliper and try to measure toe that way. I did this on my Outback a couple years ago and it worked ok.
If anyone has a good or easy idea of how to DIY check the rear toe, I'm all ears!
Thank you folks for confirming there was a problem.
Curly, I have not adjusted the toe yet. You're right about it having a big affect, I gotta try to adjust it still. I was thinking once the car is back on the ground, use the string method and a caliper and try to measure toe that way. I did this on my Outback a couple years ago and it worked ok.
If anyone has a good or easy idea of how to DIY check the rear toe, I'm all ears!
#1193
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I put about 50 miles on it. Seems fine. Stiffer ride, no surprise, also a lot more agile. Gotta do the front next, will hopefully get that done in the next couple weeks. Haven't launched it hard or anything but on the road and doing a 3rd gear roll on, it feels better. Pretty sure this made an improvement. Also this last part is probably all in my head, but I swear it feels like the rolling resistance went down. I kind of doubt that, but it sure feels like it.
Going to go order new front hubs/bearings as well in a week or so and then do the front. Then all 4 corners will be new. Plan to wire up the trans brake (gotta research best practices wiring for that) and try it out on friday. It's rained 2 out of the last 3 fridays but hopefully it's dry and I can run.
Going to go order new front hubs/bearings as well in a week or so and then do the front. Then all 4 corners will be new. Plan to wire up the trans brake (gotta research best practices wiring for that) and try it out on friday. It's rained 2 out of the last 3 fridays but hopefully it's dry and I can run.
#1194
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Been driving it. Made a couple pulls and it does seem a lot more stable now on a 1-2 shift. I think that problem is fixed. I did find the new turbo setup is heating the coils up and melted some split loom I had on some nearby wires. Plan to build a heat shield to keep the turbo heat off the coils/wires near the valve cover. Otherwise it seems to be doing well. If it runs well at this power level I'll turn it up and see what happens. Hope to get a 6 second 1/8th mile pass out of it soon!
#1195
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Heat shield built and installed, should work fine. Made form polished stainless like my other heat shields for the SC setup I made.
Trans brake is installed and tested, it works. There's an arming switching in the cup holder, and the button is just to the right of the shifter.
Trans brake is installed and tested, it works. There's an arming switching in the cup holder, and the button is just to the right of the shifter.
#1200
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Do you have a camera I could clamp to the roll bar? Or one I could put on a fender? Or somehow attach to the steering wheel to show the gauge cluster?