Moving the motor back...

[Irace86.2.0]

I’m asking this here because I feel the topic applies to swaps more than just engine mods...

My long term goals are unclear. I like the flat fa20 engine for handling and for keeping the car road legal and low profile, but I am also interested in a swap like a 2jz, k20 or 3sge beams too. I don’t know if I’ll replace this car as my daily with a Cayman, BMW 2series or something and turn the BRZ into a trailored track car, or if I’ll do a 2jz swap and keep it as a baby Supra like a true GT car. I owned two MKIVs so the 2jz is appealing, but a beams swap feels more true to the platform, yet I’d boost it and that isn’t true to the platform, so ehhh, it is an ongoing conundrum that is compounded by the fact that smog is in the future.

At this point my Harrop kit isn’t CARB legal, and at this point, I doubt it ever will be legal. I’m boost at 13 psi on E85. I’m also about to lose my access to E85 this summer. I’ll need to do my first smog at the 8 year timeline so 2021, so I have time. My choices are to go stock then reinstall, change to a different kit like JRSC, change my address to my parent’s address (they live in a CARB exempt area), buy a newer 86 or turn the car into a track car.

One consideration has been to move the engine back, whether that is for a built FA20 or for a swap like a 2jz. If I did a tranny swap this might be ideal to align the shifter to the hole. If I swapped to an engine like the 2jz then it might be better for handling moving it back. If the car is a track car anyways then cutting into the fire wall won’t be a problem because I would do an AC and HVAC delete. The problem with moving the FA20 back is the steering rack is in the way and oil pan considerations. I don’t know if other motors would have problems getting moved back besides oil pan considerations. If someone wanted to be legal then is there anything in DOT or something that is problematic for moving a FA20 back further? I’m assuming no, but I wanted to ask.

What are your opinions? Would moving the FA20 back be reasonably possible? Would it be worth it, even for a DIYer? What considerations need to be taken for any swap that requires cutting into the firewall?

CLIFF NOTES

I’m considering a swap or engine relocation in the future.

What is your thoughts or experience with cutting into the firewall to position a motor further back?

Is moving the FA20 motor back possible, beneficial, etc in conjunction with a tranny swap?

[Zer0]

I like the idea of moving the engine back further but it is wide. You would need to do a lot of careful measuring, and planning. It's been done before. You may be able to get information on how they accomplished it. Swapping the engine out is going to be a little more work. I went with a swap because I don't trust the Subaru motors ability to be reliable while pushing high HP. Otherwise I would have got the Full Race turbo kit, and pushed the engine back. If I did keep the FA20 I would have gone with a Daily Engineering dry sump system to eliminate oiling issues.

[86MLR]

For the cash and time involed I would just buy another car.

After all of your money and time the car will be worth the some of the parts, minus 50%.

[EAGLE5]

The only reason I can imagine for moving the engine back is if it fits within race regulations while improving balance. Otherwise why go through the bother? An LS or JZ swap would have so much more potential.

[86MLR]

Originally Posted by jsimon7777

The only reason I can imagine for moving the engine back is if it fits within race regulations while improving balance. Otherwise why go through the bother? An LS or JZ swap would have so much more potential.

Yeap, and out of those 2 the LS would be my vote IRT weight and balance, gearboxes for the LS are easy and relatively cheap.

[Irace86.2.0]

Originally Posted by jsimon7777

The only reason I can imagine for moving the engine back is if it fits within race regulations while improving balance. Otherwise why go through the bother? An LS or JZ swap would have so much more potential.

Please expand. What is this race regulation? I’m not familiar.

Potential, yes; actually getting to that potential, maybe; usability on a track, maybe. Seems like there is only so much power that can be reasonably put to the ground without big aero and track tires. Then again, a lot of track people eventually hang in their hat with this motor, even when built.

I’d consider another car, but getting a nice, new daily and having a cheap track car is more readonable than trying to track a Cayman, Supra or M2. I like this platform for size and looks too. An LS or 2JZ swap would be cool. I’m biased to the 2jz, yet regardless, the weight and potential change to handling concerns me. Hence the idea of recessing the engine into the firewall.

[computeruser]

What sort of racing are you going to do? Have you looked at whether class rules will allow what you are thinking of doing?

[EAGLE5]

Originally Posted by Irace86.2.0

Please expand. What is this race regulation? I’m not familiar.

Each race organization and class has its own regulations. I thought you had some class in mind where you had to keep the FA20 but could move the motor around. Otherwise it's a total waste of effort.

[Irace86.2.0]

Originally Posted by computeruser

What sort of racing are you going to do? Have you looked at whether class rules will allow what you are thinking of doing?

Originally Posted by jsimon7777

Each race organization and class has its own regulations. I thought you had some class in mind where you had to keep the FA20 but could move the motor around. Otherwise it's a total waste of effort.

I was hoping to race myself. Racing others is cool too, but I just want to drive fast at the track. I don’t care if I win.

[86MLR]

Originally Posted by Irace86.2.0

I was hoping to race myself. Racing others is cool too, but I just want to drive fast at the track. I don’t care if I win.

Spend your money on seat time then

[Irace86.2.0]

Originally Posted by 86MLR

Spend your money on seat time then

Stating the obvious?

[86MLR]

Originally Posted by Irace86.2.0

Stating the obvious?

Apparently, my mistake if I assumed were new to track days.

I see alot of people with lots of money and no skill.

Not saying this is you, but, you don't seem to know alot about the track or the different disiplines.

[DIY]

I was planning to use a EJ207 in mine which I believe is a similar size to the FA20. You could certainly move the motor a lot further back than the OEM position as I have done the measurements but then ended up going with a K24 instead.

You would be looking at a custom fabricated front cross-member at a minimum, actually there would be a substantial amount of fabrication involved and unless you are capable of doing it yourself then the costs to pay someone would be ridiculous! we are talking about a lot of hours work here by the time you build a crossmember, engine mounts, trans mounts, relocate the steering rack, possibly custom sump and all the sheet metal work around the firewall. I wouldn't even consider it for a street car.

[Irace86.2.0]

Originally Posted by 86MLR

Apparently, my mistake if I assumed were new to track days.

I see alot of people with lots of money and no skill.

Not saying this is you, but, you don't seem to know alot about the track or the different disiplines.

I get that. I just mean the plan is to go to the track all along. The point of the mods isn’t to best anyone else. The point of the mods is because they are kinda necessary.

The transmission on my boosted car is already getting to the end of its life. I bought the car used, and fifth gear already had poor engagement. Now it has grinding engagement in all situations except when I take like five slow seconds to shift and even then it can happen. Fourth is happening too but only on downshifting. The syncros may be all that needs replacing or perhaps just a few gears, but I’d rather do a transmission swap. If I wasn’t planning on going to the track or increasing the torque then I’d just swap in a new transmission, but it seems silly to be burning through crap transmissions like I know people do, and from what I’ve tead over the years, building the transmission is a waste of money to such an extent that the aftermarket support and sucess for it is almost nonexistent.

For track longevity, I’m kinda in the same boat for the motor. I’m conservatively tuned with e85 at 13 psi on a Delicious Tune with a Harrop supercharger, so I’m probably above 300whp or close to it. This is fine for the street, but I wouldn’t expect the motor to last long on the track. Maybe I’m wrong.

My choices are to build the motor and replace the Aisin transmission, or build the motor and swap in a different transmission, or to do a full swap with a new motor and tranny. I could wait until I blow the motor (hopefully not sending metal through my supercharger), but this doesn’t seem like a good idea compared to building the motor or selling it used in good condition; I’d rather be proactive.

Regardless of which option I take, if I’m switching up the parts, moving the motor back could help in a number of ways. One could be better weight balance. This could be to improve the balance over stock or not destroy the balance like with a 2jz swap. Another could be shifter alignment. While my personal labor would compound, there might be reduced complexity and cost in buying or fabricating shifter relocators or transmission adapters. Again, to use the 2jz example, a R154 would bolt up without an adapter and have more than enough power overhead for my needs, but would probably align with a recessed motor.

I like to research a lot and plan a lot, sometimes years in advance, so I’m looking for feedback on the logistics of cutting into the firewall, moving the motor back, mounting an engine back further, etc. Opinions on cost or viability is fine, but not if it isn’t constructive and becomes demeaning to a person’s abilities. Just keep it on topic please.