Tremec TKX Swap behind a BP/B6
#1
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
Tremec TKX Swap behind a BP/B6
Figured its worth documenting my swap to a Tremec tkx behind a b6 then soon into a more properly built 1.8L Since i dont really see any other in depth info on this swap anywhere.
My Initial plans were to use the quicktime bell housing but they are all on a several month back order which for all i know might keep getting pushed out and so i decided to attempt to make my own and 1600$ in the process.
The exact transmission i went with was the TCET17722 with the .81 5th and 2.87 1st, It seemed the closest match to the 5 speed gearing minus 1st gear being a little bit longer which im hoping to not be too much of an issue and I didnt want 5th to be too tall and wanted it still usable. Im still in the very early stages of the swap and don't really have too many parts other than the transmission in hand, currently waiting my clutch to arrive before i really get to working on this bell housing. My current plan was to use a Semi Custom billet single disk from Spec with a tilton adjustable hydraulic throwout bearing with a 13/16 wildwood master cylinder(hoping it gives me enough throw if not will have to go to a 7/8).
Current findings with the automatic bell housing is with it stuck onto the front of the tkx without any modification the very tip of the input shaft lands 0.37mm shorter than what the input shaft did on the 5 speed which is very close, but the splines do not go quite as far so will have to mill a bit off the automatic housing to get the distance correct depending on the flywheel used, this is assuming your using a stock miata sized/spec'ed flywheel also worth noting the TKX uses the same pilot bearing size as the miata. The TKX uses the center input shaft cover to center everything up vs using Dowels and bell housing runout seems to be very important here with these transmissions, so far the automatic housing was .005" out which is the max allowed by tremec. My plan was to turn down a disk with the bellhousing id and inputshaft cover OD on the lathe and tack it in to use to center the transmission in the bell housing(maybe offset it .005 if i can with the disk) and weld on blocks to use as mounts accordingly vs using an adapter plate. Just raising it up into the tunnel behind the bell housing it seems like its going to clear, if it doesnt its close enough that a hammer should fix it. The shifter is about 4-6 inches too short. Sikky just came out with a 6" shifter relocation that seems to be the only option out right now.
My Initial plans were to use the quicktime bell housing but they are all on a several month back order which for all i know might keep getting pushed out and so i decided to attempt to make my own and 1600$ in the process.
The exact transmission i went with was the TCET17722 with the .81 5th and 2.87 1st, It seemed the closest match to the 5 speed gearing minus 1st gear being a little bit longer which im hoping to not be too much of an issue and I didnt want 5th to be too tall and wanted it still usable. Im still in the very early stages of the swap and don't really have too many parts other than the transmission in hand, currently waiting my clutch to arrive before i really get to working on this bell housing. My current plan was to use a Semi Custom billet single disk from Spec with a tilton adjustable hydraulic throwout bearing with a 13/16 wildwood master cylinder(hoping it gives me enough throw if not will have to go to a 7/8).
Current findings with the automatic bell housing is with it stuck onto the front of the tkx without any modification the very tip of the input shaft lands 0.37mm shorter than what the input shaft did on the 5 speed which is very close, but the splines do not go quite as far so will have to mill a bit off the automatic housing to get the distance correct depending on the flywheel used, this is assuming your using a stock miata sized/spec'ed flywheel also worth noting the TKX uses the same pilot bearing size as the miata. The TKX uses the center input shaft cover to center everything up vs using Dowels and bell housing runout seems to be very important here with these transmissions, so far the automatic housing was .005" out which is the max allowed by tremec. My plan was to turn down a disk with the bellhousing id and inputshaft cover OD on the lathe and tack it in to use to center the transmission in the bell housing(maybe offset it .005 if i can with the disk) and weld on blocks to use as mounts accordingly vs using an adapter plate. Just raising it up into the tunnel behind the bell housing it seems like its going to clear, if it doesnt its close enough that a hammer should fix it. The shifter is about 4-6 inches too short. Sikky just came out with a 6" shifter relocation that seems to be the only option out right now.
Last edited by Kanaan; 11-11-2023 at 05:16 AM.
#2
Will definitely be following this as I just blew up my 3rd 6 speed this year and am considering all other options. I've got a bunch of questions:
Are these compatible with Miata flywheels?
What are your plans for driveshaft and rear diff?
Is there still space for a full 3" exhaust to fit next to it?
Are these compatible with Miata flywheels?
What are your plans for driveshaft and rear diff?
Is there still space for a full 3" exhaust to fit next to it?
#3
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
Will definitely be following this as I just blew up my 3rd 6 speed this year and am considering all other options. I've got a bunch of questions:
Are these compatible with Miata flywheels?
What are your plans for driveshaft and rear diff?
Is there still space for a full 3" exhaust to fit next to it?
Are these compatible with Miata flywheels?
What are your plans for driveshaft and rear diff?
Is there still space for a full 3" exhaust to fit next to it?
For the moment my plan was just to get a custom driveshaft for the torsen I have mainly for cost reasons just for the short term but plan on swapping it sometime in the future kinda depends when it breaks. I’d imagine you can still fit a 3” exhaust in there but no way to know till I get it all in the car and crossmember built, I’ll make sure to keep the thread up to date.
Last edited by Kanaan; 11-13-2023 at 04:47 PM.
#4
I spoke a bit with Holley on the Quick Time adapter and just general design and he was a huge help overall. It sounds like it may be more trouble than is worth to get the auto to work, but it does sound like it would be fun to make it work.
What are your plans for mounting it to the car? Just fab up a generic mount similar to what kmiata does for the ZF swap?
I just pulled the motor/trans today and am fairly confident that a TKX is the path I want to go down as well
What are your plans for mounting it to the car? Just fab up a generic mount similar to what kmiata does for the ZF swap?
I just pulled the motor/trans today and am fairly confident that a TKX is the path I want to go down as well
#5
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
I spoke a bit with Holley on the Quick Time adapter and just general design and he was a huge help overall. It sounds like it may be more trouble than is worth to get the auto to work, but it does sound like it would be fun to make it work.
What are your plans for mounting it to the car? Just fab up a generic mount similar to what kmiata does for the ZF swap?
I just pulled the motor/trans today and am fairly confident that a TKX is the path I want to go down as well
What are your plans for mounting it to the car? Just fab up a generic mount similar to what kmiata does for the ZF swap?
I just pulled the motor/trans today and am fairly confident that a TKX is the path I want to go down as well
#6
When I spoke to him, he said that date seemed accurate. Non-surprisingly, they only sell a few of them a year, so that probably plays into the date if they are taking a bunch of orders and making them all at once. I still need to put my order in for one, but I also don't need the car to be running until March 1st.
#7
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
When I spoke to him, he said that date seemed accurate. Non-surprisingly, they only sell a few of them a year, so that probably plays into the date if they are taking a bunch of orders and making them all at once. I still need to put my order in for one, but I also don't need the car to be running until March 1st.
I just put in my order for one last night, ran into a snag building this, part I needed to make doesn’t fit on my lathe, still might slowly work on it but and if it works out in time can always cancel but I don’t see that happening, with the right tools this auto housing could totally be done.
#9
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
no real date but as soon as I could, not for any real reason I just hate having it down for too long. Might chunk it back together with a 5 speed and be easier on it since it’ll be few months. Had the transmission out just measuring stuff.
#12
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
curious what ratio one you went with, I went with the 2.87 1st and .81 5th one and I’m still on the fence on the decision but it’s too late it’s already sitting in my floor lol mainly didn’t want my 5th to just be lugging st 65 down the highway and if I did ever need 5th in the 1/4 it wouldn’t be a huge drop
#13
curious what ratio one you went with, I went with the 2.87 1st and .81 5th one and I’m still on the fence on the decision but it’s too late it’s already sitting in my floor lol mainly didn’t want my 5th to just be lugging st 65 down the highway and if I did ever need 5th in the 1/4 it wouldn’t be a huge drop
ratios ... I have 2 rear end gear sets to try with it 4.1 and 3.63
I plan to start with the 3.63
#14
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
I was probably going to run a stock 4.10 for a bit but I believe I’m going to pick up a ford 8.8 later this evening but I doubt I’ll do that swap for a little while. Just about any ratio and diff type out there for them. Hopefully the more people that order the QuickTime housing the more likely they are to hit their time estimate but who knows.
#15
I also ordered mine from Holley and am hoping they stick to their 1/16/24 date. I've called so many shops and no one has it.
I'm still debating which ratios I'll go with for the TKX. The car is full track so I only care about how it feels out there.
I've got a Fuji 3.63 in now and am waiting for OSGiken to come in from supermiata. My plan was to stick with that and just weld the stock carrier
I'm still debating which ratios I'll go with for the TKX. The car is full track so I only care about how it feels out there.
I've got a Fuji 3.63 in now and am waiting for OSGiken to come in from supermiata. My plan was to stick with that and just weld the stock carrier
Last edited by ryansmig; 11-29-2023 at 02:43 PM.
#16
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
Also got this in the other day from Sikky, they just came out with their TKX relocation, so just in time. They only have a 6" one which i think is a little bit too long but got a 2" offset to maybe fine tune it a little more.
#18
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
I also ordered mine from Holley and am hoping they stick to their 1/16/24 date. I've called so many shops and no one has it.
I'm still debating which ratios I'll go with for the TKX. The car is full track so I only care about how it feels out there.
I've got a Fuji 3.63 in now and am waiting for OSGiken to come in from supermiata. My plan was to stick with that and just weld the stock carrier
I'm still debating which ratios I'll go with for the TKX. The car is full track so I only care about how it feels out there.
I've got a Fuji 3.63 in now and am waiting for OSGiken to come in from supermiata. My plan was to stick with that and just weld the stock carrier
did anyone else just get their order canceled and says its "Obsolete"??? ordered from holley and i no longer can find that item on the site either... hopefully some error
#19
Cpt. Slow
iTrader: (25)
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,197
Total Cats: 1,136
It's not, they did the same for the ecotec bell housing we wanted, but said they still have all the drawings, you'll just have to email them to get a "custom" one made. Supposedly won't be too expensive since they have all the drawings, but it won't be as cheap as what they listed.
Email them, mention you could maybe sell ~10-20 of them, and as long as they don't make you buy all of them, they might offer you a discount.
Email them, mention you could maybe sell ~10-20 of them, and as long as they don't make you buy all of them, they might offer you a discount.
#20
Junior Member
Thread Starter
Join Date: Nov 2019
Location: Vinita, Oklahoma
Posts: 65
Total Cats: 11
It's not, they did the same for the ecotec bell housing we wanted, but said they still have all the drawings, you'll just have to email them to get a "custom" one made. Supposedly won't be too expensive since they have all the drawings, but it won't be as cheap as what they listed.
Email them, mention you could maybe sell ~10-20 of them, and as long as they don't make you buy all of them, they might offer you a discount.
Email them, mention you could maybe sell ~10-20 of them, and as long as they don't make you buy all of them, they might offer you a discount.