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Nice work man! Ya I'd bet a solidly mounted tranny and diff has to feel pretty good as the drivetrain simply can't move around as much. Be curious to hear your thoughts on NVH and if it increased noticeably after you get some more time to drive the car. I'd guess it will increase a bit but probably a good tradeoff for a track car.
Holy crap dude. Your ability and capacity to get stuff done in record time is outstanding and motivating. Great job! Give us a video of the exhaust note when it’s all said and done
Nice work man! Ya I'd bet a solidly mounted tranny and diff has to feel pretty good as the drivetrain simply can't move around as much. Be curious to hear your thoughts on NVH and if it increased noticeably after you get some more time to drive the car. I'd guess it will increase a bit but probably a good tradeoff for a track car.
Thanks to both of you guys! I’ve been motivated to get the car running at full boost again. Won’t be making it to the track Friday (getting the exhaust rerouted), but she’ll be back on track soon!
I’ll have to give some feedback on the NVH once the exhaust is back on the car. Any increase is currently being overshadowed by the open downpipe dumping directly under the driver’s seat lol.
Originally Posted by redursidae
Holy crap dude. Your ability and capacity to get stuff done in record time is outstanding and motivating. Great job! Give us a video of the exhaust note when it’s all said and done
Appreciate it, Ricardo! I’ll post an exhaust vid this weekend. Been meaning to since I got the resonator removed last weekend.
I’ll have to give some feedback on the NVH once the exhaust is back on the car. Any increase is currently being overshadowed by the open downpipe dumping directly under the driver’s seat lol.
Cool ya I figured with the open downpipe right below you it probably overpowers everything. Question for you how much did the tranny swap cost? Just curious as I haven't given it a thought. 4-5k?
Once it’s all said and done, I think it’s gonna total out somewhere in the mid-6k range. Swap kit, clutch, and PPF delete were $4,500 shipped. I got my trans for $1,350 shipped, NB axles cost me $150, then I still need to get the exhaust modified before I can call it done. Then I’ll probably spend a couple/few hundred bucks on whatever speedometer fix I decide on. Could’ve saved a few hundred bucks by going with an OEM clutch but figured I’d go overkill with the ACT since I plan for more power in the future.
It was a lot of scratch but I figure I’m going to have this car for a LONG time and was going to have to bulletproof the drivetrain for future plans at some point. I’ve done three transmission pulls now in the last two months and would like to be done with that for the year
I'm also very impressed, good work! I'm also interested to hear how nvh is, and if there's any driveline vibrations. I've seen others fight issues with that doing this swap so I hope yours is smooth as butter!
Looking good! 100 LB stranded picture frame hanging works pretty well to hold exhausts together if your current setup fails. Ask me how I know...
Yeah, that's a lot for the swap, but if it saves you the cost of a couple 6 speeds and the time/effort of swapping those in then I suppose it's worth it. Buy once, cry once (I say as I plan to go to a 6 speed in the future).
Damn so ~6k minimum. I will be running off wastegate pressure forever! Definitely not cheap but what is these days. Ultimately if it means you'll have a reliable/bulletproof drivetrain it's worth it (busting 6 spds regularly isnt cheap either). These build threads are good inspiration to get off my **** and put in some work on the car.
I'm also very impressed, good work! I'm also interested to hear how nvh is, and if there's any driveline vibrations. I've seen others fight issues with that doing this swap so I hope yours is smooth as butter!
Thanks man! And absolutely, I'll report back after this weekend. My work and home are both right next to the toll road so I jumped straight on there when I picked the car up to avoid any drama on the surface streets with cops because of the loud exhaust. I basically spent 90% of the drive cruising at 70mph where it felt pretty smooth. Noticed a potential bit of driveline vibration on decel in 4th gear when I got close to home but it felt about the same as my stock drivetrain. More details to come...
Originally Posted by SimBa
Looking good! 100 LB stranded picture frame hanging works pretty well to hold exhausts together if your current setup fails. Ask me how I know...
Oooh, that's much better than the safety wire I'm using to hold up the downpipe right now haha. I've only gotta drive a few miles to the exhaust shop on Friday otherwise I'd hit up Amazon and buy a roll. Hell, maybe I should have a roll of that laying around just in case. I figured I would use some leftover pipe strap to hold the downpipe up before I remembered I had safety wire lol.
Yeah, that's a lot for the swap, but if it saves you the cost of a couple 6 speeds and the time/effort of swapping those in then I suppose it's worth it. Buy once, cry once (I say as I plan to go to a 6 speed in the future).
Originally Posted by SlowTeg
Damn so ~6k minimum. I will be running off wastegate pressure forever! Definitely not cheap but what is these days. Ultimately if it means you'll have a reliable/bulletproof drivetrain it's worth it (busting 6 spds regularly isnt cheap either). These build threads are good inspiration to get off my **** and put in some work on the car.
Haha I keep telling myself I'd have stayed at 210whp if I was smart. In fact, that's what I tell all my friends to do when they inquire about turbo-ing their Miatas! Glad I could provide a bit of inspo. I'd be lying if I said watching all your guys' build threads wasn't keeping me motivated as well.
I never did anything about the speedometer. K-Miata has a solution and other solutions exist but I never pursued it because it is mostly a track car and speedos don't matter there.
I probably should've done something because I have awesome revlimiter guages.
Copy that. Yeah, it’s for sure not necessary on a mostly-track car. I’m probably still going to pursue a solution because I drive this thing on the street a decent bit and would still like the odometer/tripodometer to work. It’s not urgent though, will probably wait a couple weeks before I start on anything.
Car’s back from the exhaust shop! Downpipe and muffler inlet pipe both modified to fit the new trans and diff braces. They pulled it off the lift before I got there unfortunately but I’ll post pics of the exhaust next week.
The exhaust note definitely changed, and the whole chassis feels stiffer than it did even with the original V8R frame rail braces. There’s definitely additional driveline vibration compared to before but it’s not make or break for me. The shifter doesn’t move around anymore and that alone makes me super happy.
The car looks great man, cleaner than usual! It looks proud. We gotta see some pics of that exhaust ASAP! Glad to hear about the vibrations, at least they aren't a dealbreaker. I know ole greg peters had a hell of a time getting his to not want to shake itself apart on the highway. I'd bet you can fix that with a lighter/more precise driveshaft down the line. You might also measure your trans ouput angle, and the diff input angle, and make sure those match. I bet there's adjustment in your kit if you haven't checked that yet, and it definitely makes things smoother when those are exactly the same angle.
I'm all about a more permanent speedo fix, but a cheap/easy fix is a spare android phone (no cell service), some kind of 3d printed mount, and an offline speedometer app (like this). Just thinkin cheap/dirty, since you are all-in with that trans swap.
Thanks man! It was the lighting for sure, although I’m sure she’s proud of her new driveline! I still gotta wash that degreaser residue off her haha.
Well, dammit, you just HAD to say it! I took the car out on the freeway just now and it has a GNARLY driveline vibration starting at 70mph. It’s to the point that the tach will start vibrating violently once you get to 3,500 rpm in 6th gear. Luckily, this didn’t occur when I drove the car home on the freeway last week (I even checked over a couple videos I took that day), so I think it probably has to do with the exhaust shop removing the diff brace today.
It’s raining tomorrow (only on the weekend, again) so I’m gonna take the car to the shop and check the driveline angles like you said. Still gotta swap in the right hand non-stub axle as well, swap in the Redline fluid(s) that DV recommended, and do a couple other things on the car. The fun continues
Yes, pinion angle was important for mine as well. When right it's smooth but things still hum a little, which is to be expected with such firm mounting. I also have no sound deadening padding beneath the carpet anymore. I did put some peel and stick on the package shelf and that helped.
Six, thanks. I was going to hit you up next and see if you had the issue. My trans angle started at 2.4 and my diff was at 2.8. I have now spaced the trans down to 2.1 and diff to 2.3. Also found that my transmission crossmember to bushing holes were drilled too far to the left, pulling the transmission to the left and messing up the driveline angle when everything was cinched down. I fixed that but the vibration hasn't changed at all. You don't happen to remember the pinion angle you settled on, do you?
Six, thanks. I was going to hit you up next and see if you had the issue. My trans angle started at 2.4 and my diff was at 2.8. I have now spaced the trans down to 2.1 and diff to 2.3. Also found that my transmission crossmember to bushing holes were drilled too far to the left, pulling the transmission to the left and messing up the driveline angle when everything was cinched down. I fixed that but the vibration hasn't changed at all. You don't happen to remember the pinion angle you settled on, do you?
I'm too lazy to re-watch his videos, but Greg Peters had this issue and eventually got it resolved. Sorry I brought it up, but this is one of the things that always scared me away from drivetrain swaps. Interested to see what you find!
Thanks man, I remember he had a similar issue and think he solved it by going to a Getrag diff (great). I'll re-watch later to try and gain some insight.
So far I've tried a slew of driveline angles all the way from 1.5* to 2.5* on both the trans and diff and nothing has made a difference. Some angles produced a slightly worse vibration. I'm at a loss right now.
Tried everything as far as pinion and trans angles go. Currently have the Diff at 2* and trans at 2.1* no change. Bolt checked the whole driveline, eyeballed everything for out of spec runout, swapped in the NB axle on the right side, checked to make sure same size bolts/nuts/washers were used on both ends of the driveshaft. No change.
I emailed KPower outlining my situation and may take the driveshaft to a local shop Monday or Tuesday to make sure it’s balanced properly. If it’s the culprit, maybe I’ll have a lighter driveshaft made.
Original driveline angles. Thought fixing those was gonna solve it for sure.
04-08-2024, 09:46 PM
Definitely not cheap but what is these days. Ultimately if it means you'll have a reliable/bulletproof drivetrain it's worth it (busting 6 spds regularly isnt cheap either). These build threads are good inspiration to get off my **** and put in some work on the car.
