Pat's Ebay Turbo Compound Boost Build
#1222
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Are you pre-loading the drivetrain so there is zero slack on launch? Axles can shear like that when you get a whiplash type effect through the drive train due to backlash in cvs and diff... and I'd imagine it would be 10 times worse with a trans brake and instant power.
That or it's just too much torque.
That or it's just too much torque.
#1223
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On their website they have axles for the regular miata diff, but not the MSM. I have a MSM diff. I could still call, maybe they have them or can make them.
I have poly bushings in the rear, with 250lb/inch springs on adjustable perches, on stock not-bilstein shocks, stock ride height. Shocks work, but they have stock damping which is almost no compression dampening, and not a lot of rebound damping.
Are you pre-loading the drivetrain so there is zero slack on launch? Axles can shear like that when you get a whiplash type effect through the drive train due to backlash in cvs and diff... and I'd imagine it would be 10 times worse with a trans brake and instant power.
That or it's just too much torque.
That or it's just too much torque.
Question- So if I can get axles for 800 from the drive shaft shop rated for "400hp", should I? I'm making at least 500 flywheel hp, and with drag radials/trans brake, that's the perfect combo for twisting axles in half. Seems like that could be a waste if they aren't much better than what I already break.
Basically, it's probably gonna be 3K to swap in a ford diff (2K for DSS axles, 1K for everything else with DIY mounts for the diff). Should I save up and do the ford setup, or spend 800-1000 on custom axles and find out how much a MSM diff can take or if the new axles are any stronger? Tempted to just save up and do a ford setup and never worry about it again, but that will be a down-the-road upgrade.
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Yeah there is, it started from the outer surface as expected, right where the radius begins on the axle near the outer CV. it's a lathed surface, and the crack started the the minor-diameter of the groove from the machine work. I think finishing a set of axles would definitely help. Maybe I should do that and save up incase that's not the fix.
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VIDEO VIDEO VIDEO VIDEO!!!!!!!!!! I FINALLY GOT A VIDEO FROM FRIDAY AT THE TRACK!!!!!
The turbos are so loud, it's sounds nuts outside the car. Sounds like a jet engine going down the track.
https://www.youtube.com/watch?v=sm11...ature=youtu.be
The turbos are so loud, it's sounds nuts outside the car. Sounds like a jet engine going down the track.
https://www.youtube.com/watch?v=sm11...ature=youtu.be
#1228
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https://v8roadsters.com/shop/uncateg...al-conversion/
$1500. Find a $300 getrag in the junkyard.
Good to go.
$1500. Find a $300 getrag in the junkyard.
Good to go.
#1229
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VIDEO VIDEO VIDEO VIDEO!!!!!!!!!! I FINALLY GOT A VIDEO FROM FRIDAY AT THE TRACK!!!!!
The turbos are so loud, it's sounds nuts outside the car. Sounds like a jet engine going down the track.
https://www.youtube.com/watch?v=sm11...ature=youtu.be
The turbos are so loud, it's sounds nuts outside the car. Sounds like a jet engine going down the track.
https://www.youtube.com/watch?v=sm11...ature=youtu.be
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Lovvvvvvvvvvveeeeeeeeee it
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Glad you guys like it! I watched the video, and I slammed my head into the seat on the launch... LOL I had my helmet on after that.
I emailed V8 Roadsters and Martin about 8.8 conversions, and sent an email to thedriveshaftshop and Raxle axles about axles options. See if I get any replies, or I'll just call tomorrow if I loose my patience.
I can probably buy axles and broached hubs and fab the rest, but wanna see what a kit cost since that's surely faster/easier.
I emailed V8 Roadsters and Martin about 8.8 conversions, and sent an email to thedriveshaftshop and Raxle axles about axles options. See if I get any replies, or I'll just call tomorrow if I loose my patience.
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#1233
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Pat
Congrats on setting your new personal bests. That is a seriously quick car!
Did you try putting in a lower value of MAP, say 60 kPa, and try blipping the throttle? This would make it easy to test anyway.
Also, I do know that for some of the programmable outputs, if you change the settings, you need to turn the MS off and then back on, for the changes to actually take effect.
Only other thing that comes to mind, is to confirm you have nothing else that could be also trying to use the injector out F pin as an output.
Would love to see an in car video, when you get the chance
Congrats on setting your new personal bests. That is a seriously quick car!
I'm having a problem with the MS. I setup an output to trigger an LED light when I hit 8 PSI, but it never turned the LED on. It's setup correctly in software, and if I put say, 20 as the trigger instead of 180, the LED lights since I idle at 38-40 kPa. Put a value above idle kPa and LED goes off. But when I do the launch, the LEDs never light. No idea why, but that is the reason I launched at 16 PSI on the last run because I could hear the thing was making a lot of boost but the LED never came on so I just launched. I gotta figure this out before going back.
Also, I do know that for some of the programmable outputs, if you change the settings, you need to turn the MS off and then back on, for the changes to actually take effect.
Only other thing that comes to mind, is to confirm you have nothing else that could be also trying to use the injector out F pin as an output.
Would love to see an in car video, when you get the chance
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#1235
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Originally Posted by patsmx5
VIDEO VIDEO VIDEO VIDEO!!!!!!!!!! I FINALLY GOT A VIDEO FROM FRIDAY AT THE TRACK!!!!!
The turbos are so loud, it's sounds nuts outside the car. Sounds like a jet engine going down the track.
https://www.youtube.com/watch?v=sm11...ature=youtu.be
The turbos are so loud, it's sounds nuts outside the car. Sounds like a jet engine going down the track.
https://www.youtube.com/watch?v=sm11...ature=youtu.be
#1237
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Pat
Congrats on setting your new personal bests. That is a seriously quick car!
Did you try putting in a lower value of MAP, say 60 kPa, and try blipping the throttle? This would make it easy to test anyway.
Also, I do know that for some of the programmable outputs, if you change the settings, you need to turn the MS off and then back on, for the changes to actually take effect.
Only other thing that comes to mind, is to confirm you have nothing else that could be also trying to use the injector out F pin as an output.
Would love to see an in car video, when you get the chance![](https://www.miataturbo.net/images/smilies/smile.gif)
Congrats on setting your new personal bests. That is a seriously quick car!
Did you try putting in a lower value of MAP, say 60 kPa, and try blipping the throttle? This would make it easy to test anyway.
Also, I do know that for some of the programmable outputs, if you change the settings, you need to turn the MS off and then back on, for the changes to actually take effect.
Only other thing that comes to mind, is to confirm you have nothing else that could be also trying to use the injector out F pin as an output.
Would love to see an in car video, when you get the chance
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Thanks!
It was close. The back of the car didn't squat as much as it used to, so I'm happy with that.
I did not. Just asked some questions about their 8.8 axles. Still undecided right now what I'm going to do. I have 4 or 5 spare MSM axles, a spare MSM diff, and the MSM diff and axles in the car now (of which one of the axles has like 10 miles on it with no hard driving at all, the other axle and diff have been abused but otherwise work great). So I can definitely sell all the MSM stuff and recoup some of my money on a ford swap. It's got me looking into the cost and work it would take to do the ford conversion.
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Yea, beach marks propagating from an initiation point that's at the root of a lathe cut. That was cyclical fatigue initiated cracks... although not that many cycles. Smooth that bitch out and polish it up real nice and see what breaks next.
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Going ford 8.8 aluminum Diff and DSS 900HP 31 spline axles. Probably run 3.55 gears, probably running TrueTrac LSD. Diff and axles already ordered, and diff has 3.55s in it already. Still reading up on various LSDs for this, but TrueTrac seem to be a good one and strong.
Going to put my spare MSM diff/axles up for sale soon! Will also sell the stuff in the car after the swap is done.
EDITED for more detail.
Going to put my spare MSM diff/axles up for sale soon! Will also sell the stuff in the car after the swap is done.
EDITED for more detail.
Last edited by patsmx5; 04-04-2017 at 07:29 PM.