Hello Internet! So its been a long time coming but Big Country Labs have decided to build a Demo car!
We thought long and hard about what Chassis to build as we wanted something modern with plenty of aftermarket support and of course it had to be able to house a 1JZ or 2JZ engine swap. After trawling craigslist we found a Scion FRS rolling shell for sale (complete car, minus the engine and gearbox). So after talking with the seller and working out a price we snapped it up!
Now that we had acquired a chassis we needed to find the power plant. Being huge fans of the Toyota JZ engines and running them for years in drift and street cars we had to get another one! We turned to the internet again and found a complete running and driving Lexus SC300 with a 1JZGTE swap and R154 transmission. After talking with the selling we brought it and drove it away.
The SC300 had a ton of aftermarket parts including an aftermarket clutch kit, Single turbo kit, Stand Alone ECU, upgraded fuel system, front mount intercooler kit etc.
Being that the car was purchased for the purpose of ripping apart we got straight into it and removed the running gear. Before we did this we gave the Toyota 1JZGTE engine a quick compression check to confirm it was a winner.
As soon as we got the engine and transmission out of the SC300 we cracked the box off to check out the clutch and check its condition.
We were very happy to see a Exedy hyper single in brand new condition!
Now with the engine and transmission removed it was time to start stripping the chassis down. First the front end was stripped down so we could check clearance and see what will need cutting and what we can leave. As we plan to street drive this car we want to keep the cutting to a minimum and retain as many creature comforts as possible.
We also put the 1JZ engine on a stand so we can strip it down and swap the sump over to a Front sump so it will clear the front cross member.
On a recent trip to Portland we stopped by Xcessive Manufacturing and picked up a set of FRS / GT86 to 1JZGTE / 2JZGTE Motor mounts and brackets to suit our 1JZ non vvti engine. Having this off the shelf mounts will make mounting the engine nice and easy!
On inspection of the transmission tunnel and measuring the size of the R154 gearbox we are going to have to modify the stock tunnel mounts to fit the R154 in as the factory gear box is super small compared to the big Toyota R box.
Next we removed the seats and dash (still need to do the carpet) so we can access the tunnel and wiring to make it easy for modification. Since we are welding on the transmissions tunnel we don't want anything to catch fire!
TIP: Make sure you use the correct E10 Torx Socket to undo the front seat bolts or you will more than likely strip them!
So with the 1JZ on a stand we removed the rear sump setup to make way for the front sump setup so it will clear the crossmember. While the engine is out and pulled down we decided to tape it up and paint the block in Black.
We ordered some new parts from Toyota so the JZ engine can be reliable when installed. We purchased a new water pump, oil pump, front and rear mail seals, O rings etc...
After fitting all the new parts to the engine it was time to look at the Transmission tunnel to see how the R154 gearbox will fit and what needed to be modified. The Scion FRS / Toyota GT86 / Subaru BRZ transmission tunnel has a brace for the factory gearbox crossmember which restricts the size of transmission that will bolt in without modification.
As you can see the factory gearbox mounting points on the FRS / GT86 / BRZ really take up a lot of room in the tunnel. So after doing a few measurements we confirmed it needed to be removed.
Instead of getting an angle grinder and cutting into the tunnel we went and purchased a Spot Weld Cutter and drilled out each of the spot welds holding that brace in place. The spot weld cutter essentially cuts around the spot weld making it easy to separate each panel with out making a mess.
TIP: Drill a small pilot hole so your spot weld cutting drill bit wont slip while starting the cut.
The OEM transmission tunnel cage brace is actually 3 pieces. We first drilled out the 2 actual mounting points to see if the gearbox would fit?
After removing these mounts we test fitted the gearbox in the tunnel, but it was still fouling on the transmission brace that was left. So once again we jumped under the car and started drilling out the remaining brace with the handy spot weld cutter. Here is what the brace looks like when removed. All up there was about 52 spot welds that needed to be drilled to remove the mounts and the cage brace.
With the factory gearbox mounts and bracing out of the way, we bolted the transmission to the engine to trial fit in the bay to check if everything clears and fits.
After the modification the R154 gearbox fits in the FRS / GT86 / BRZ tunnel, Its still a tight fit but its in there. The factory FA20 engine and transmission setup in the Scion FRS / Toyota GT86 / Subaru BRZ is a very different shape to the 1JZGTE / 2JZGTE engine and the R154 gearbox as you can see from all the space above the gearbox.
1JZ just chillin the the engine bay. We trial fitted the turbo kit up and found out that everything will bolt on with no modification.
On the inside of the car we noticed that the transmission shifter didn't quite sit in the factory location. The shifter housing will need to be extended by about 2.5 inches in order to sit in the factory position.
Instead is extending the factory R154 shifter housing we used a JZX110 Chaser factory extended shifter which sits the gear knob in a close to factory position. The "110" shifter is known to be the smoothest shifter the Toyota R box was released with.
*The "110" extension does require a little modification if you have the old style R154 transmission like us. Only 2 of the 6 bolts line up so a couple bolt holes needed to be re tapped and also some tabs welded on and tapped so it all worked like factory.
As you can see its sitting pretty good in the OEM GT86 shifter hole now.
Now that we know the shifter and transmission fit we took the car down to Trophy Designs to help fabricate the gearbox cross member mounts. Since we wanted to keep this a street car we wanted them to look as factory as possible, so we decided to simply TIG weld the factory mounts back on in a new location.
So we Sanded the paint down to give it a good clean up, Positioned the mounts where we wanted them and got to welding
Being that the transmissions tunnel is thin sheet metal, an experienced TIG welder is essential to creating a neat finish and more importantly not blow any holes in the metal. Now its all looking nice and Factory, Next we made a crossmember to bolt the gearbox to our new mounts
We actually used a crossmember that was already lazer cut to suit a R154 into JZX chassis. We did this as the holes for the gearbox mount and mounts were already Lazer cut and it was easy to cut up and weld the pieces to fit out setup.
With the engine and gearbox now mounted it was time to start looking at how we could get the cooling system to fit and what parts were needed to keep this big motor cooling efficiently in a small engine bay. After measuring the space up front and comparing sizes of the factory radiator, it was pretty clear that the OEM unit was not going to cut the mustard.