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Discussion Starter #1 (Edited)
Because stupid cannot be overdone and I'm a glutton for punishment - Welcome to the marriage of Toyota and Honda.

At speed during a Road Atlanta race.



After 4 years and 14,000 race miles it's time for an upgrade. Out goes the inline 6 cylinder iron block with antique fuel injection. In goes a K24A2.



Disadvantages:
It doesn't just bolt in... WTF. Some fabrication necessary.

Advantages:
20 years newer technology
Lighter
More powerful
Great aftermarket support
Bolts directly to the Toyota drivetrain in OE position with custom McGregor bell housing.
Uses OE Honda clutch and flywheel. Toyota disc, shift fork, bearings.



Lighter? OMG - Aluminum vs iron block. I wish that I had scale.




Plenty of room in the engine bay. The oil pan is sitting on the engine crossmember/steering rack in this photo.




The bell housing is tight to the firewall but not able to sit any lower yet. 2-3 inches lower and it should give me the room to push back and align the shifter.






Pardon the crappy cell phone pic. This is the front of the oil pan. I believe that a front sump pan will work fine. I'll do a bit of surgery on the front crossmember and oil pan.




Rear of oil pan. I should be able to take 2-3" off this to clear the steering rack and drain toward a front sump.




I'll be fabricating some motor mounts that should mate nicely with the OE platforms.

 

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Bolts directly to the Toyota drivetrain in OE position with custom McGregor bell housing.
This made me LOL --- I would hope a custom bellhousing for this application would allow the engine to bolt to the toyota gearbox, haha


Interesting project, I haven't heard of any kswapped Supra -- only 3sgte swapped Supras. Should bring it out to Supras Invade Las Vegas this year.


You guys wouldn't happen to be the same group that build a MX3 for Chump/Lemons, would you?
 

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Discussion Starter #6
You guys wouldn't happen to be the same group that build a MX3 for Chump/Lemons, would you?
Same team. We still have the (2) MX3s but I wanted to build a RWD car.

I've contacted Dave at K Miata and the pan won't work with the position of my crossmember. They are working on a BMW pan that will be front-sump and might serve me well. For now I'll be modifying an OE steel pan to fit.
 

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Same team. We still have the (2) MX3s but I wanted to build a RWD car.
awesome! We built a MX3 for Chump as well, thinking we were the only lunatics, then found your team had done quite well with it... I've heard the most winning Enduro team?

Looking forward to this Supra build
 

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This is awesome, I wouldn't be surprised if the old engine alone was as heavy as the k24 and trans together
 

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Discussion Starter #9
awesome! We built a MX3 for Chump as well, thinking we were the only lunatics, then found your team had done quite well with it... I've heard the most winning Enduro team?

Looking forward to this Supra build
I'm sure that we're not the most successful endurance team, but we have our share of wins in all three cars in Lemons, Chump, WRL, and SCCA bracket enduro. The MX3 turned out to be a great FWD platform for endurance racing, and the 1.8 BP swap was fast enough to compete 3 years ago. Another team dropped a 2.5 v6 KL into one and it became a rocket.

I hope to do some surgery on the engine crossmember today to give me some oil pan clearance.
 

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In for updates although it's been 2 months. I'm starting a similar project after finding out about this bellhousing. I have a K24Z1 I'll be putting in my MGB that already had a W55 put into it so the car has half of the drivetrain already. Onto the hard bits. I'm interested in what parts you used for the clutch, wiring/pcm, and how you did the fuel?
 

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Discussion Starter #11
In for updates although it's been 2 months. I'm starting a similar project after finding out about this bellhousing.
After some medical issues and a book deadline to meet in September, I'm back at the K24 swap. Lots of posts to follow.

Test fit #2 - oil pan and oil pump removed. I would have removed the front timing cover also except the damn pulley bolt is quite "snug". Ordering the pulley tool later.

There will be no clearance issues with the hood or firewall with the engine lowered into a reasonable position. I placed an inclinometer on the valve cover and it's less than 1* from horizontal with the car on 4 wheels.





The transmission mount is slightly offset rearward, so I turned it around and pushed everything slightly forward to bolt it up. I can live with the small change in position and the driveshaft splines that mate with the output shaft are plenty long to account for the difference.





With the trans bolted snug and engine level I have 6" of clearance between the oil pan mating surface and as low as I'll care to cut and weld the crossmember. I need 6.5" to clear the pan so I'll be spacing the crossmember down 1". Tell me that 1/2" of clearance is enough...





The rear of the pan will clear the windage tray of of a K20 oil pump set-up.



So the silhouette of the pan will look something like the red line. I will have to push out the front and front sides to gain back the volume. I'll have to relocate the drain plug also.

 

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Discussion Starter #12
Crossmember surgery

I removed enough material to leave 11" width after adding new metal. The pan is 10" wide. I made 1" thick aluminum spacers to lower the crossmember for more clearance.




My welding is getting better. I used 1/8" steel to box in the cut, it's thicker than the original metal. The net result is a lot more oil volume in it's original position.






Spacers in place.




Painted and in place. The next test fit will let me know the oil pump situation. I hope that I can leave an OE pump in place now and only modify the pan.

 

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Discussion Starter #13
Updates and questions:

I popped the engine back in today to see what the oil pickup situation looked like... not good. The pickup would be right where the steering rack is currently occupying space. The good news is that I was able to leave more of the oil pan in place, but I will definitely have to add a bulge to the front of the pan to gain back some lost volume. This is the portion of the pan I cut out.



I believe that I left enough space for the engine to move a bit, which leads to my most pressing question. OE engine mounts use three 12mm threaded bosses on each side of the block. These bosses are at least 6" behind the OE Toyota engine mounting plates. Almost directly in line with the OE mount plates are 10mm threaded bosses that may serve as engine mount points, so the question is will three 10mm threaded bolts on each side be enough to use as engine mounting points (See photos with three bolts on each side)? The other option is to fabricate and weld new mounts to the frame rails and use the Honda mount points.








The shallow end of the oil pan will be just about level with the "low oil" mark on the dipstick.

 

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Discussion Starter #14
My best oil pan option is a rear sump similar to the Kmiata oil pan. The rear sump will be baffled and I hope to get 4.5-5qt of capacity in that space, along with another 1.5-2 qts in the front sump.

I set the engine back into the car and bolted up the transmission mount. Then I took some time to make sure the engine was in line with the chassis and the oil pan was sitting flat. The K24 is tilted about 15 degrees backward in the TSX and the oil pan is shaped like a wedge. I have about 12 degrees of engine tilt toward the passenger side with the oil pan sitting level.

I spent yesterday cutting, drilling and welding 1/4" steel to make a motor mount for the passenger side. I'll continue to use the GM transmission mounts in pace of OE Supra engine mounts. The driver side will be a bit more complicated due to the water pump housing being in the way. The plate on the engine mounts with 4 bolts.




Even without the left engine mount I can now cut some cardboard to make a template for the oil pan. I'm hoping for 4.5-5 qts of capacity in the rear sump, and another 1.5 qts in the front sump where the oil pump resides.
 

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Discussion Starter #15
Driver side motor mount. I'll be the guineau pig to find out if two 10mm bolts into the block is enough to support long-term abuse.




I wish that I could get a better photo, but no lift in my garage. This is a pic looking up from the floor to the oil pan. I'll have space to fabricate a modified "T" oil pan. The two threaded bosses on the left side of the photo are for steering rack lines that no longer exist. They will be trimmed and plugged flush.



Last week I started mocking up a rear sump oil pan design. My first attempt with cardboard was a total failure...




So I bought a sheet of foam house insulation and set about cutting and gluing parts together to create a 3D version. The insulation is easy to cut and shape, and remains exactly where it is supposed to while moving the engine. Basically it will be a "T" shape pan with kick-outs left and right. If my calculations are correct it should net me 5 qts of capacity in that section (probably close to 7 qts overall). A new pan should arrive tomorrow as a "clean sheet" to make the new pan.

My welder (this needs to be TIG welded) won't have time until January so I left the engine in the car to work out some more fabrication problems. One compromise to stay within the budget was always going to be a "space issue" with the intake plumbing. In a TSX the intake is on the front of the engine, but turn it 90 degrees counterclockwise and the throttle body is in the firewall of the Supra. The only option was to cut a hole in the firewall that will allow enough space for the throttle body and a curved intake tube. I will have to build a "box" and weld it to the inside of the firewall to cover the hardware. The good news is that the OE throttle cable reaches and will easily operate the Accord throttle body (cable vs drive by wire).

 

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Discussion Starter #16
Intake one night, exhaust the next :)

Header mounted to engine, with a 3" to 2.5" adapter (the actual header outlet is only 2.5"). About 6" below the outlet is the boot for the tie rod - it shouldn't be a problem with the bend radius I'm using (see third photo). If you look closely you can see the pink foam that I used to mock up the oil pan. The exhaust will clear it by a couple of inches, and it runs almost perfectly in line with the current exhaust muffler.




Although it may not look like it, there is plenty of room between the frame rail and the header.




The basics. The flex joint will be welded in and I'll install a v-band at the header and where it meets the original exhaust.



Exhaust work is complete except for final adjustments of hangars. Flex joint is welded in on both sides, and there are v-bands at the muffler (you can see it on the left), and the header. O2 bung was welded in an easily accessible spot.






A 135 degree silicone elbow arrived today - this will get the intake back into the engine bay from the throttle body. It's 5mm thick but seems a bit flimsy and might not stay round under vacuum. The angle will be perfect to get a DIY CAI to the front left corner of the car, and the throttle cable clears it perfectly. The brake line meandering through the area will be re-bent.

 

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Discussion Starter #17 (Edited)
I cobbled together a CAI from old parts. I'll build a box around the filter and route cold air in from behind the air dam.



Now the real fun begins.

Yes, there are great Honda engine management solutions for K24 swaps (Hondata, KPRO), but I already have a Megasquirt in the car so why not do it the hard way? :p
This OE harness (and a few other sensors) will terminate at a 32-pin plug on the firewall. The backside of the plug will have a short run to the MS3 in the passenger footwell.



Electrical work takes forever, but at least it's moving forward.

Reduced alternator and starter harness, running through a new grommet.




New lower electrical panel in the passenger footwell. The driver switch panel is also undergoing some serious rewiring. The rats nest is going away.




One addition to the fuel system was a Corvette fuel filter/regulator (canister on the right). K24 needs 50psi rail pressure, and this component provides 58 and will be available at any parts store. The return from the internal regulator exits the back of the unit (black hose) to sump. In case you're wondering: The frame you see is the support for a sheetmetal bulkhead that keeps this area separated from the cabin in case of fire. At the top of the photo (toward the front of the car) is a 1/2 gallon fuel sump. Fuel is pumped into the sump from a low pressure fuel pump in the tank. Fuel then exits the bottom of the sump into a filter then a high pressure pump. The original system is a return-type with a regulator near the rail and a return line back to the fuel tank.

 

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Discussion Starter #18 (Edited)
Electricity is hard! 2 weeks and 40 hours in the garage herding electrons, but there is finally light at the end of the tunnel.

This is the 32-pin plug on the engine side. Other than the alternator and starter, every engine wire runs through this.




Almost every MS3 wire is now connected to its proper place. I've spent a lot of time lengthening/adjusting wires in preparation for tidying everything up with wire sheath. At the top right you can see the cabin side of the 32-pin plug - the plate it's mounted on closes the hole where the OE harness came through the firewall.



Designing and building your own electrical system from scratch is time consuming, but when you throw the main switch and see all of the non-engine things working (and not letting any smoke out) it's very satisfying. Headlights (apex and spots on separate fuses), tailights and brake lights (each on their own circuit in case an accident takes one out), dash, transponder, and switch panel components seem good.




While I'm waiting for an oil pan I replaced the timing chain tensioner and started a few other projects.


The cooling system was the next project. I bought a hose with multiple bends as a starting point, and a few couplers. The hose will run under the intake and exit above the alternator. A large chunk of aluminum was removed from the water pump housing that used to hold the OE belt tensioner. This opened space for the hose to exit, and it's almost a direct shot to the Toyota radiator inlet.






The thermostat housing originally had the inlet facing backwards toward the firewall, but after a bit of modification I turned the inlet 180 degrees to face mostly forward. I'll be able to use hose bends to easily get to the lower radiator outlet.

 

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Discussion Starter #20
Even before I built the driver side motor mount it was bothering me that it was only held in place with 2 bolts. A friend visited and suggested that it might be good to spread the load along more than one plane, so I cut and welded an extension that reaches the water pump housing. They're only M8 bolts but I feel better about that mount now.

 
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