Miata LFX Swap (Singular Motorsports & Good-Win Racing)
12-15-2017, 01:15 AM
#761
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Always so focused on moving forward; next race, next improvement, next season, next steps. Every once in a while though it's good to glance back to appreciate how far we've come, and when I have pages of to-do lists for the next season, it helps to remind myself it doesn't happen over-night.
2011 Buttonwillow 13CW (my first track day) - 2:13.9
2017 Buttonwillow 13CW (Superlap Battle) - 1:48.4
2011 Buttonwillow 13CW (my first track day) - 2:13.9
2017 Buttonwillow 13CW (Superlap Battle) - 1:48.4
Last edited by ThePass; 12-15-2017 at 01:30 AM.
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12-18-2017, 01:19 PM
#762
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A post about goals.
Those who have been following along with me for a while will recall I’ve posted about goals a couple times over the years. It started small, but years went by with goals achieved, each more ambitious than the last, and both the car and driver kept improving. Then I attended my first Superlap Battle. I realized I had built a quick Miata, but I wanted to make this little Miata something that is fast no matter what you stack it up against. I set my sights on breaking the 1:50 barrier at Buttonwillow (something a Miata had never done before) and taking a podium in Limited RWD at Superlap Battle. This year, I won the class and went 1:48.
Along the way I’ve had some amazing businesses and friends believing in these goals and helping along. Goodwin Racing has put its faith in this program and supported it in countless ways. Blackbird Fabworx made sure I was racing in a safe chassis and have been instrumental from concept to creation in many of the crazy ideas we’ve come up with. V8Roadsters made it possible for the car to have the powertrain it needs to compete on this level. Singular (specifically Sean) has shared in this adventure through thick and thin. Rocky's Miatomotive has lent a hand more times than I can count. Feal Suspension put together a coilover that I could drive fast and confidently on. There was a time I was just racing for me, but these days the HyperMiata is about a lot more than that. There are a lot of businesses and people that I look up to behind this effort, and there are so many of you who have followed along over the years, contributing and cheering us on, these days we're racing for all of you as well.
So, what’s next?
Re-building the car over the last two years, especially in the last few months, it was all push push push to get to SLB 2017. In the midst of that craziness, I had this funny kind of daydream idea that some day when I won at SLB I would sit back and relax. I didn’t expect to win LRWD the first year I returned, but the irony is that doing so has made me more hungry than ever to make the car faster. I can’t wait to get this next season started, to get out to the garage and start refining and improving things, to get back on the race track turning more laps and tuning.
In 2018 we return to SLB with a target on us. There’s no way to know what’s in the works in shops across the US that may be ready by next year, 1:48 was enough for the win this year but next year it probably won’t be. If you aren't moving forward, you're falling behind so we need to set a new goal to push towards. The track record for Limited RWD is 1:44.602, set by Cody Kishel in the seriously prepped Excelsior Motorsports C6 Corvette in 2014. That was the last year the class allowed flat bottom floors and 80tw tires, and nobody has run anywhere close to that before or since. That’s the aim. If someone else is going to take the win in 2018, they’ll need to be on pace for a new record because I intend to be.
3.881 seconds to find from this year’s time. Time to get to work.
Respecting our elders even as we strive to surpass them:
Those who have been following along with me for a while will recall I’ve posted about goals a couple times over the years. It started small, but years went by with goals achieved, each more ambitious than the last, and both the car and driver kept improving. Then I attended my first Superlap Battle. I realized I had built a quick Miata, but I wanted to make this little Miata something that is fast no matter what you stack it up against. I set my sights on breaking the 1:50 barrier at Buttonwillow (something a Miata had never done before) and taking a podium in Limited RWD at Superlap Battle. This year, I won the class and went 1:48.
Along the way I’ve had some amazing businesses and friends believing in these goals and helping along. Goodwin Racing has put its faith in this program and supported it in countless ways. Blackbird Fabworx made sure I was racing in a safe chassis and have been instrumental from concept to creation in many of the crazy ideas we’ve come up with. V8Roadsters made it possible for the car to have the powertrain it needs to compete on this level. Singular (specifically Sean) has shared in this adventure through thick and thin. Rocky's Miatomotive has lent a hand more times than I can count. Feal Suspension put together a coilover that I could drive fast and confidently on. There was a time I was just racing for me, but these days the HyperMiata is about a lot more than that. There are a lot of businesses and people that I look up to behind this effort, and there are so many of you who have followed along over the years, contributing and cheering us on, these days we're racing for all of you as well.
So, what’s next?
Re-building the car over the last two years, especially in the last few months, it was all push push push to get to SLB 2017. In the midst of that craziness, I had this funny kind of daydream idea that some day when I won at SLB I would sit back and relax. I didn’t expect to win LRWD the first year I returned, but the irony is that doing so has made me more hungry than ever to make the car faster. I can’t wait to get this next season started, to get out to the garage and start refining and improving things, to get back on the race track turning more laps and tuning.
In 2018 we return to SLB with a target on us. There’s no way to know what’s in the works in shops across the US that may be ready by next year, 1:48 was enough for the win this year but next year it probably won’t be. If you aren't moving forward, you're falling behind so we need to set a new goal to push towards. The track record for Limited RWD is 1:44.602, set by Cody Kishel in the seriously prepped Excelsior Motorsports C6 Corvette in 2014. That was the last year the class allowed flat bottom floors and 80tw tires, and nobody has run anywhere close to that before or since. That’s the aim. If someone else is going to take the win in 2018, they’ll need to be on pace for a new record because I intend to be.
3.881 seconds to find from this year’s time. Time to get to work.
Respecting our elders even as we strive to surpass them:
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12-21-2017, 01:33 AM
#764
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LFX Price List
One of the big questions everyone has had since the new drivetrain plans were announced was "what does it cost to do this swap?" I couldn't accurately answer that until the swap was done. When we're 'keyboard racing' and comparing swap options it's all too easy to add up the big ticket items and figure that gets it in the ballpark, but anyone who has done a swap knows that there are dozens of items you don't think of and they all add up. Therefore, just about every swap out there costs more to really do than people guess. To help demystify this subject for the LFX, I promised I'd post the real costs of the swap when done.
That time has come! However, a lot of details on the HyperMiata are irrelevant for the next guy doing a fun street/track build. So, to give a good representation of an "average" swap I've put together the cost list below:
LFX Swap Items/Costs
I trimmed out the pure race car stuff and subbed in options that I'd be choosing for a good average build. The list assumes minimum fabrication ability and includes any off-the-shelf options that make the swap easier, such as V8R's plug and play radiator and ECU with tune. Yes, you could definitely do an LFX swap for less than this list shows if you trimmed it down to the necessities and did a budget version of some items. Costs for fabricated items like the coolant hard lines and the exhaust are estimates that assume having the work done at a shop.
The only fabrication item not listed is the cutting of the rear corners of the engine bay and then welding in the frame rail corner caps - but the cost of those caps from V8R are listed. I think most DIY guys would tackle this bit in their garage.
Not listed here is a solution for gauges. The race car got a digital dash, a custom wiring harness and an array of extra sensors - not stuff you need for a street car, but in a way it made the job a little easier rather than trying to get the stock gauges to play nice with the new electronics. V8R lists a set of gauges in the works on their site, so there may be an easy solution for this in the future.
Finally, I've included all of the random incidentals that I came across - stuff like the new GM speed sensor, clutch slave, front differential bushing etc. etc. (all things that turned out to need replacing in the parts I got from the junkyard). These unplanned items will be different for each person, but I'm including all of mine to serve as a realistic and comprehensive example for the swap.
One of the big questions everyone has had since the new drivetrain plans were announced was "what does it cost to do this swap?" I couldn't accurately answer that until the swap was done. When we're 'keyboard racing' and comparing swap options it's all too easy to add up the big ticket items and figure that gets it in the ballpark, but anyone who has done a swap knows that there are dozens of items you don't think of and they all add up. Therefore, just about every swap out there costs more to really do than people guess. To help demystify this subject for the LFX, I promised I'd post the real costs of the swap when done.
That time has come! However, a lot of details on the HyperMiata are irrelevant for the next guy doing a fun street/track build. So, to give a good representation of an "average" swap I've put together the cost list below:
LFX Swap Items/Costs
I trimmed out the pure race car stuff and subbed in options that I'd be choosing for a good average build. The list assumes minimum fabrication ability and includes any off-the-shelf options that make the swap easier, such as V8R's plug and play radiator and ECU with tune. Yes, you could definitely do an LFX swap for less than this list shows if you trimmed it down to the necessities and did a budget version of some items. Costs for fabricated items like the coolant hard lines and the exhaust are estimates that assume having the work done at a shop.
The only fabrication item not listed is the cutting of the rear corners of the engine bay and then welding in the frame rail corner caps - but the cost of those caps from V8R are listed. I think most DIY guys would tackle this bit in their garage.
Not listed here is a solution for gauges. The race car got a digital dash, a custom wiring harness and an array of extra sensors - not stuff you need for a street car, but in a way it made the job a little easier rather than trying to get the stock gauges to play nice with the new electronics. V8R lists a set of gauges in the works on their site, so there may be an easy solution for this in the future.
Finally, I've included all of the random incidentals that I came across - stuff like the new GM speed sensor, clutch slave, front differential bushing etc. etc. (all things that turned out to need replacing in the parts I got from the junkyard). These unplanned items will be different for each person, but I'm including all of mine to serve as a realistic and comprehensive example for the swap.
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12-22-2017, 12:50 PM
#766
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I do have an MV7. That isn't a list of how to replicate my car 
For an average build I'd do the MV5. Ratio differences are small, the MV5 is about $400 cheaper and you can even get it from the same donor Camaro you get the motor from if you look for a Manual car. And most important of all, I still don't have my MV7 shifting right, so until I can get it sorted out and working properly I'd recommend an MV5 to anyone else.
For an average build I'd do the MV5. Ratio differences are small, the MV5 is about $400 cheaper and you can even get it from the same donor Camaro you get the motor from if you look for a Manual car. And most important of all, I still don't have my MV7 shifting right, so until I can get it sorted out and working properly I'd recommend an MV5 to anyone else.
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12-22-2017, 03:20 PM
#767
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i hear you. we have the same shifting problem with the spec clutch. we had no problems shifting when we had the dual-mass flywheel. but then the flywheel became it's own problem and we decided enough of that and went with spec. hoping you can discover a solution and will share it with us.
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12-22-2017, 04:34 PM
#768
I've been thinking about this shifting issue everyone seems to be having. I noticed something similar when I drove the V8R demo car at MATG. Before committing to doing this swap I went and test drove a stock LFX Camaro to see how it shifted. I didn't have any shifting issues in any conditions encountered during about 30 minutes of testing. I notice that in the stock GM applications there are braces between the transmission and the shifter assembly/mount where it's attached to the cars body. The V8R modded shifter setup eliminates those braces and has the shift linkage itself as the sole connection. I'm wondering if there is enough movement there to cause a problem?
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12-23-2017, 01:28 PM
#769
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I'm not sure what you experienced when you drove their car at the GAP but I have a ton of seat time in their cars as well as my own, all using the same shifter and have never had a issue on the street or the track. If the shift plate was moving in relation to the transmission it would cause missed shifts and trouble finding gears in general.
I would venture to guess with Ryan's car to be an issue related to the clutch disengaging completely, whether it is related to the actual pressure plate, master cylinder, or even pilot bearing. Maybe a synchro issue but I doubt it. I'm pretty sure we are running the same set up (master, clutch, flywheel) and I've had no issues, but the pedal ratio could be different between the generations.
I would start with a borescope and a inspection hole to measure airgap and slave travel.
I would venture to guess with Ryan's car to be an issue related to the clutch disengaging completely, whether it is related to the actual pressure plate, master cylinder, or even pilot bearing. Maybe a synchro issue but I doubt it. I'm pretty sure we are running the same set up (master, clutch, flywheel) and I've had no issues, but the pedal ratio could be different between the generations.
I would start with a borescope and a inspection hole to measure airgap and slave travel.
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12-23-2017, 02:09 PM
#770
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i'm pretty sure it's the clutch. i had no problems when i was running the oem clutch/flywheel. but when the dual-mass flywheel crapped out we replaced it with the spec clutch/flywheel. that's when the problem reared its ugly head. i don't really want to go back to the oem setup. sometimes, even though you have the clutch pedal on the floor, it won't want to come out of gear when you're slowing for a traffic light in addition to the shifting problems. i'm convinced it doesn't have anything to do with the way v8 roadsters modified the shift linkage.
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12-24-2017, 12:47 AM
#771
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Yeah the primary issue is in clutch engagement/disengagement. I have two problems, which I am fairly certain are unrelated.
The first problem is definitely clutch engagement. Minimal when cold, worsens once you have some heat in the clutch. At a stop with pedal on the floor, you've got to really shove it into gear and the car will start to roll forward because the clutch isn't fully disengaged. Grinds on shifts unless you time it right and match revs to where the next gear wants to be. Hydraulics have all checked out, I've tried two MC piston sizes, and the full range of rod length adjustment at the pedal. SPEC designed the clutch/flywheel for the LFX/MV5 combo, so I'm aware of the fact that we are operating on an assumption that the MV7 doesn't have some small difference we don't realize - and that the factory clutch/fly can adjust for that while the SPEC unit can't. It would be great if we knew someone who had an MV5 and the SPEC clutch to confirm/deny whether that combo works as expected. To try to get to the bottom of that I ordered an MV5 a couple weeks ago, and took measurements of TOB position and range of motion to compare with the MV7. I don't want to be disassembling the car over and over to try to sort these things out so a couple days ago I ordered a second MV7, when that arrives I'm going to take the same measurements and compare to the MV5's. If those are different, we might have found something. If they are the same, we can cross "MV7 different than MV5?" off the list and next step would be to contact SPEC and ask them why their clutch doesn't work - or more politely, find out what they want to see for clutch finger preload and range of motion - and then see if we need to shim the TOB or similar to achieve that.
The second unrelated issue is a very stiff and sticky shifter feel, with no return to center in neutral. I *THINK* I have this one narrowed down to an issue in the linkage. The problem when you are dealing with a new drivetrain you have no experience with is you don't know what to expect, what is normal and what isn't. I didn't know what to expect with the first MV7 I got. But, when that MV5 arrived recently, I noticed the ball/socket pivot on the end of the shift rod that comes out of the trans had more range of motion and moved much more freely than I recall of the one on my MV7. This is going off memory so I could be wrong, and I can't use the MV5 anyways (different crossmember mount and driveshaft) but when the second MV7 arrives soon I am hoping that one also has a free-moving pivot. My car will be back on the lift in about a week and at that time I'll get under there and disconnect the shifter linkage to see if my memory is right on that one being much stiffer. If it is, and MV7 #2 is looser, that might be my shifter issue solved.
The first problem is definitely clutch engagement. Minimal when cold, worsens once you have some heat in the clutch. At a stop with pedal on the floor, you've got to really shove it into gear and the car will start to roll forward because the clutch isn't fully disengaged. Grinds on shifts unless you time it right and match revs to where the next gear wants to be. Hydraulics have all checked out, I've tried two MC piston sizes, and the full range of rod length adjustment at the pedal. SPEC designed the clutch/flywheel for the LFX/MV5 combo, so I'm aware of the fact that we are operating on an assumption that the MV7 doesn't have some small difference we don't realize - and that the factory clutch/fly can adjust for that while the SPEC unit can't. It would be great if we knew someone who had an MV5 and the SPEC clutch to confirm/deny whether that combo works as expected. To try to get to the bottom of that I ordered an MV5 a couple weeks ago, and took measurements of TOB position and range of motion to compare with the MV7. I don't want to be disassembling the car over and over to try to sort these things out so a couple days ago I ordered a second MV7, when that arrives I'm going to take the same measurements and compare to the MV5's. If those are different, we might have found something. If they are the same, we can cross "MV7 different than MV5?" off the list and next step would be to contact SPEC and ask them why their clutch doesn't work - or more politely, find out what they want to see for clutch finger preload and range of motion - and then see if we need to shim the TOB or similar to achieve that.
The second unrelated issue is a very stiff and sticky shifter feel, with no return to center in neutral. I *THINK* I have this one narrowed down to an issue in the linkage. The problem when you are dealing with a new drivetrain you have no experience with is you don't know what to expect, what is normal and what isn't. I didn't know what to expect with the first MV7 I got. But, when that MV5 arrived recently, I noticed the ball/socket pivot on the end of the shift rod that comes out of the trans had more range of motion and moved much more freely than I recall of the one on my MV7. This is going off memory so I could be wrong, and I can't use the MV5 anyways (different crossmember mount and driveshaft) but when the second MV7 arrives soon I am hoping that one also has a free-moving pivot. My car will be back on the lift in about a week and at that time I'll get under there and disconnect the shifter linkage to see if my memory is right on that one being much stiffer. If it is, and MV7 #2 is looser, that might be my shifter issue solved.
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12-24-2017, 07:58 AM
#772
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Cross reference the Camaro clutch/flywheel to the Cadillac and see if the part numbers are the same.
I'm running the MV5 with the same clutch and flywheel as you, while clutch release may be a little low everything functions as it's supposed to.
I'm running the MV5 with the same clutch and flywheel as you, while clutch release may be a little low everything functions as it's supposed to.
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12-24-2017, 10:13 AM
#774
Yeah the primary issue is in clutch engagement/disengagement. I have two problems, which I am fairly certain are unrelated.
The first problem is definitely clutch engagement. Minimal when cold, worsens once you have some heat in the clutch. At a stop with pedal on the floor, you've got to really shove it into gear and the car will start to roll forward because the clutch isn't fully disengaged. Grinds on shifts unless you time it right and match revs to where the next gear wants to be. Hydraulics have all checked out, I've tried two MC piston sizes, and the full range of rod length adjustment at the pedal. SPEC designed the clutch/flywheel for the LFX/MV5 combo, so I'm aware of the fact that we are operating on an assumption that the MV7 doesn't have some small difference we don't realize - and that the factory clutch/fly can adjust for that while the SPEC unit can't. It would be great if we knew someone who had an MV5 and the SPEC clutch to confirm/deny whether that combo works as expected. To try to get to the bottom of that I ordered an MV5 a couple weeks ago, and took measurements of TOB position and range of motion to compare with the MV7. I don't want to be disassembling the car over and over to try to sort these things out so a couple days ago I ordered a second MV7, when that arrives I'm going to take the same measurements and compare to the MV5's. If those are different, we might have found something. If they are the same, we can cross "MV7 different than MV5?" off the list and next step would be to contact SPEC and ask them why their clutch doesn't work - or more politely, find out what they want to see for clutch finger preload and range of motion - and then see if we need to shim the TOB or similar to achieve that.
The second unrelated issue is a very stiff and sticky shifter feel, with no return to center in neutral. I *THINK* I have this one narrowed down to an issue in the linkage. The problem when you are dealing with a new drivetrain you have no experience with is you don't know what to expect, what is normal and what isn't. I didn't know what to expect with the first MV7 I got. But, when that MV5 arrived recently, I noticed the ball/socket pivot on the end of the shift rod that comes out of the trans had more range of motion and moved much more freely than I recall of the one on my MV7. This is going off memory so I could be wrong, and I can't use the MV5 anyways (different crossmember mount and driveshaft) but when the second MV7 arrives soon I am hoping that one also has a free-moving pivot. My car will be back on the lift in about a week and at that time I'll get under there and disconnect the shifter linkage to see if my memory is right on that one being much stiffer. If it is, and MV7 #2 is looser, that might be my shifter issue solved.
The first problem is definitely clutch engagement. Minimal when cold, worsens once you have some heat in the clutch. At a stop with pedal on the floor, you've got to really shove it into gear and the car will start to roll forward because the clutch isn't fully disengaged. Grinds on shifts unless you time it right and match revs to where the next gear wants to be. Hydraulics have all checked out, I've tried two MC piston sizes, and the full range of rod length adjustment at the pedal. SPEC designed the clutch/flywheel for the LFX/MV5 combo, so I'm aware of the fact that we are operating on an assumption that the MV7 doesn't have some small difference we don't realize - and that the factory clutch/fly can adjust for that while the SPEC unit can't. It would be great if we knew someone who had an MV5 and the SPEC clutch to confirm/deny whether that combo works as expected. To try to get to the bottom of that I ordered an MV5 a couple weeks ago, and took measurements of TOB position and range of motion to compare with the MV7. I don't want to be disassembling the car over and over to try to sort these things out so a couple days ago I ordered a second MV7, when that arrives I'm going to take the same measurements and compare to the MV5's. If those are different, we might have found something. If they are the same, we can cross "MV7 different than MV5?" off the list and next step would be to contact SPEC and ask them why their clutch doesn't work - or more politely, find out what they want to see for clutch finger preload and range of motion - and then see if we need to shim the TOB or similar to achieve that.
The second unrelated issue is a very stiff and sticky shifter feel, with no return to center in neutral. I *THINK* I have this one narrowed down to an issue in the linkage. The problem when you are dealing with a new drivetrain you have no experience with is you don't know what to expect, what is normal and what isn't. I didn't know what to expect with the first MV7 I got. But, when that MV5 arrived recently, I noticed the ball/socket pivot on the end of the shift rod that comes out of the trans had more range of motion and moved much more freely than I recall of the one on my MV7. This is going off memory so I could be wrong, and I can't use the MV5 anyways (different crossmember mount and driveshaft) but when the second MV7 arrives soon I am hoping that one also has a free-moving pivot. My car will be back on the lift in about a week and at that time I'll get under there and disconnect the shifter linkage to see if my memory is right on that one being much stiffer. If it is, and MV7 #2 is looser, that might be my shifter issue solved.
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12-26-2017, 12:29 PM
#775
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Cross reference the Camaro clutch/flywheel to the Cadillac and see if the part numbers are the same.
I'm running the MV5 with the same clutch and flywheel as you, while clutch release may be a little low everything functions as it's supposed to.
GM parts direct list them as different part numbers so I'd check with GM to make sure they're not interchangeable
I'm running the MV5 with the same clutch and flywheel as you, while clutch release may be a little low everything functions as it's supposed to.
GM parts direct list them as different part numbers so I'd check with GM to make sure they're not interchangeable
Why not just setup your tob like you would for a performance one anyways? Measure all your **** and then shim the TOB so that its got like 50thou of clearance when all the way sucked in. Its what you'd have to do if you got a proper racing clutch anyways. We're too spoiled with our japanese drivetrains just working, all the american stuff I've at to work on if you use anything more than a stock replacement clutch you have to shim to tob.
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01-04-2018, 01:15 PM
#776
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Tons of things going on, a lot of it is little details. Need a small bracket here or a tweak of something there and before you know it many hours have disappeared.
Some of the big stuff...
The Getrag diff was not operating like an limited slip unit. At first we chalked it up to the fluid and additive still needing to get cycled around better since it hadn't driven around much, but after a lot of figure 8's in the parking lot and still no improvement I started digging. GM superseded part numbers so when you call your GM contact to find out if the PN on your diff is for an LSD, they might know that number was superseded by a different number or they miiiiight tell you that's not a number that comes up in their system and have no idea. Eventually we got it nailed down and it turns out the salvage yard that advertised this diff as an LSD unit got it wrong. That was over a year ago so nothing to do now but buy another one.
As for those part numbers...
3.42 NOT LSD:
15793753 - superseded now by 25873499
3.42 LSD:
15793754 - superseded now by 25873500
New diff arrived, correct original PN on it. That diff now lives in the car.
Some of the big stuff...
The Getrag diff was not operating like an limited slip unit. At first we chalked it up to the fluid and additive still needing to get cycled around better since it hadn't driven around much, but after a lot of figure 8's in the parking lot and still no improvement I started digging. GM superseded part numbers so when you call your GM contact to find out if the PN on your diff is for an LSD, they might know that number was superseded by a different number or they miiiiight tell you that's not a number that comes up in their system and have no idea. Eventually we got it nailed down and it turns out the salvage yard that advertised this diff as an LSD unit got it wrong. That was over a year ago so nothing to do now but buy another one.
As for those part numbers...
3.42 NOT LSD:
15793753 - superseded now by 25873499
3.42 LSD:
15793754 - superseded now by 25873500
New diff arrived, correct original PN on it. That diff now lives in the car.
Digging this post up from a while back.
Just received a Getrag 3.42 P/N 15793754. Did you go through and replace all the seals before installing it?
Thanks,
Ryan
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01-06-2018, 12:54 AM
#777
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We did not replace axle seals. I did purchase some and we intended to but the existing seals were rather stubborn and I decided no sense messing with something that was working so before damaging the ones in there I declared that we should leave them alone.
We DID however replace the front bushing (the existing one was shot in both units I've received so far, and I don't like how much negative space is in the OE bushing anyways) to a urethane version from Creative Steel, the "street" 75 durometer.
We DID however replace the front bushing (the existing one was shot in both units I've received so far, and I don't like how much negative space is in the OE bushing anyways) to a urethane version from Creative Steel, the "street" 75 durometer.
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01-06-2018, 11:54 PM
#778
Senior Member
Join Date: May 2007
Location: Atlanta
Posts: 997
Total Cats: 156
And I'll throw in .02 - Instead of the creative steel, we snagged Energy Suspension 3.2125 ($20 for 2 bushings), ran it through the bandsaw to shorten it, used the Harbor Freight ball joint press to push out the old rubber leaving the steel insert, cleaned the rubber remnants with a wire brush, popped the new one in. I highly suggest doing this before you weld in the front plates and set the driveshaft angle. The old one was completely shot and after installing the new one our pinion angle changed - we'll have to do some metalwork to fix it now (either cutting off the plates and rewelding them to the subframe, or grinding out the hole and filling up the excess, or really making the hole larger, then welding plates with bolt sized holes to fit over those... either way, a lot easier to do it right the first time).
Differential Bushing $16 DIY option
Differential Bushing $16 DIY option
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01-07-2018, 12:12 AM
#779
Junior Member
iTrader: (1)
Join Date: Sep 2017
Location: Huntington Beach, CA
Posts: 230
Total Cats: 22
Thanks for the info.
I ended up ordering a revshift 95 durometer replacement front bushing. Hopefully it will work well.
I'll definitely install it before welding the front diff mount.
I ended up ordering a revshift 95 durometer replacement front bushing. Hopefully it will work well.
I'll definitely install it before welding the front diff mount.
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01-10-2018, 02:16 PM
#780
Supporting Vendor
Thread Starter
iTrader: (3)
Join Date: Jul 2006
Location: San Diego
Posts: 3,303
Total Cats: 1,216
We have the shifter feel/return-to-center issue finally pinpointed!
Trans #1 had a seized pivot on the shift rod from the start. We just didn't know it because it was our first experience with a trans from this family. With trans #2 (an MV5 I bought to take comparison measurements from) and trans #3 (an MV7 to replace the one in this car) in our hands it became immediately clear that these pivoted differently than I recalled #1 doing. With the car back in the shop and on the rack I was able to disconnect the shift linkage last night and confirm the difference.
That pivot allows for the off-axis motion the shifter makes as it moves side-to-side. Without the pivot the shifter is binding with just about any motion.
Trans #1 had a seized pivot on the shift rod from the start. We just didn't know it because it was our first experience with a trans from this family. With trans #2 (an MV5 I bought to take comparison measurements from) and trans #3 (an MV7 to replace the one in this car) in our hands it became immediately clear that these pivoted differently than I recalled #1 doing. With the car back in the shop and on the rack I was able to disconnect the shift linkage last night and confirm the difference.
That pivot allows for the off-axis motion the shifter makes as it moves side-to-side. Without the pivot the shifter is binding with just about any motion.
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