My Project Impreza AWD Rotary
 

I like to compete in the SCCA rallycross events here in Michigan because it is something to do during the cold icy winter when autocross doesn't exist. My winter/rallycross car is an '82 Rx-7 and while this is good when there is traction it is terrible slow in the snow and ice.
Attachment 711083
Being a devote rotorhead I hated seeing how slow the Rx-7 was and so after a year of thinking what to do, considering whether to convert the Rx7 like the Rod Millen cars or swap rotaries into an Audi Quattro, Geo Tracker, or Impreza. The Impreza looked to have the most potential and after taking many measurements at junk yards I bought a high mileage 1998 Impreza L AWD at an auction. The best thing about it is the body is in very good condition meaning very little corrosion.
So this is where I'm at with it at this time:
Attachment 711084
This shows S4 13B housings bolted to the oil pan with a turbo on for good measure! The more I get into this the better this installation looks. There is room in front of the standard radiator for the oil cooler, exhaust routing looks easy, no clearance issues if I run a turbo, and the standard S4 oil pan fits perfectly. I will need to modify the Subaru cross member so the rear edge of the sump can sit about half an inch lower. In addition engine mounts will need to be fabbed up to this cross member.
Attachment 711085
There will be issues with the S4 waterpump nose fouling the radiator but I wonder whether an FD pump would help because it is shorter. Also not sure if the alternator would clear the hood. Fabbing the trans/engine adapter plate and mounting the starter motor are going to be challenging.
Attachment 711086
This shows a 12A on the left and the 2,2L Impreza boxer engine side by side. Interestingly these engines are exactly the same length from transmission face to front pulley! Initially I thought only the 12A would fit but now with the 13B mocked up in position it also fits. Rather have the 13B for extra torque, parts availability, and ease of turbo installation.

so your gonna make a adapter plater for the subie tranny and hook it to a 13b?
this looks like a awsome idea..
all the best with the project

it seems like a cool project...
Ill like to see how this ends up..

good luck ;)

Yes 13B with Subaru AWD trans.

GL with this project...cant wait to see it on dirt road

Good to see someone putting two great ideas together. Subaru AWD and a boosted rotary should make one hell of a weapon.

Great project. What is your timeline for getting it one the road?

At the latest it has got to be on the road for next winter. So Nov. 2010.

Anyone know the height of a TII intake above the rotor housings? Need to know whether this it would clear the underside of the hood.

i messured off the top of the square on my rotor housing to the top of the manifold and got
7"1/4 camera angle makes it look like 1/2" but its not..

heres how i messured
https://www.rx7club.com/attachment.p...1&d=1263006499

heres the square was talking about
https://www.rx7club.com/attachment.p...1&d=1263006411

if the water pump is a real issue for clearence u can always to a electric one.

i really like your project i started to look for subies on craigslist lol..:icon_tup:

cheers
chris

Awesome project.


Turbo AWD+Rotary=Win

Very original

This looks awesome I can't wait to see how it all works

Well this thread has my attention. I was expecting all talk no car, but your already working on it, sweet deal!

haha awesome. I posted up about this years ago and everyone flamed the hell out of me. Nobody like the idea.

Keep up the good work! I'd love to see this happen.

Thanks for all the encouraging responses and thanks BLWFLY for the intake height measurements.
I need to place the hood back on today and check the clearance to see if a standard TII intake fits. Will also start mocking up the trans adapter plate.
If someone has an FD waterpump could they measure the distance from the face where it bolts up to the housing and the hub face where the pulley bolts on? This I will compare to an S4/S5 waterpump length and determine whether it will interfere with the radiator fans.

Been done...Tokyo Auto Salon...circa 2003ish...

that is a friggin awsome car..

Thought you all would like that..***NOTE OIL COOLER PLACEMENT****

There was one getting around New Zealand a few years back as well. Not sure what happened to it - someone might know?

After mocking up an adapter plate out of wood and installing 13B dummy engine found there is about 7 inchs clearance under the hood for intake manifold. Elimination of one of the hood strengthening braces will give another 1/2" clearance.
Standard NA intake definately won't fit due to lack of hood clearance.
Attachment 711097
Took a look at how the engine mounting might look for the 13B
Attachment 711098

Next I'm going to install the adapter onto a half BP 12A and see how it looks in the engine bay. I think this engine would work well with a turbo and fuel injection. I like the idea of a top mount intercooler positioned in the std Subaru location with a WRX hood scoop.

i would think at least a 13b turbo engine for this car how much dose the car weigh?

whats the power out put of the subie engine?

12abp turbo should do tho.

1998 Impreza with 2.2L had 137hp and weighed 2700 lbs. To be competitive in M4 rallycross I'll need at least 200 - 250hp.

That's just an awesome project, I'm putting a 13B N/A in a 1300lbs 1959 Bugeye. If a 13B fits in here it will fit in anything! Good luck and Keep us posted. Dave

awesome project. cant wait to see the final product.

any more info on your 13b bug?^^

any more info on your 13b bug?^^[/QUOTE]

Bugeye is in hibernation till March 1st. But I have been busy polishing.

Has anyone even seen a AWD Rotary, just sounds cool! Can't wait to see a vid of this one!

I have an extra FD water pump laying around so I measured from the mounting surface on the back side to the surface on the front side which the pulley mounts to. I got 2-9/16"

Thanks for measuring that. A 1st/2nd gen pump is 3- 3/4". This means the FD is 1-3/16" shorter which makes a 13B do-able. Assuming FD pulleys could be installed on the e-shaft and alternator. Just need to run the belt so it turns the pump backwards like an FD. I think an FD pump can run on a 2nd gen 13B waterpump housing from what I've read. May need to install the FD w/pump housing though.
The 2nd gen pump interferes with the electric fan mounts on the standard Subaru radiator and I don't know if this radiator will cool well enough for rallycross.

Any more progress? I'm looking forward to watching the rest of this!

I have the 12A attached to the trans with the mocked up adapter. With the 12A "properly" located the nose of the waterpump just interferes with the radiator fan shroud. With this shroud removed there is about 21/4" clearance to the radiator. Also it is likely the alternator will need to be mounted off to the side because it interferes with the hood. I'm going to stay with the 12A at this point mainly because I don't have a 13B together and ready to install. A 13B will fit lengthwise but a different radiator fan would be needed. I suspect a thicker radiator will be required sometime down the road to help with cooling.
Currently working on fabricating the front engine mounts.

this thread has my full attention,
cant wait to see how it turns out
I saw a AUDI Quatro with a s4 13b Turbo
he did it cause he wanted AWD with rotary power
hauled ass
keep up the work it looks awesome

That would have been a cool car. My buddy has a '86 5000 quattro turbo. It's a damn heavy car but at 15PSI of boost it goes pretty good. I keep bugging him to get rid of the 5 cylinder and the CIS injection and put a rotary in there.

I would use the 13b but that is me.
and like you said you dont have a put together 13b.
Also are you are still going to turbo the 12A, or are you going to keep it N/A?
But the 12A is BP I have no clue if that would be enough gumption to pull a subbie as a N/A alone
but combined with turbo it will be a force to be reckoned with:nod:
keep posting this is so awesome

http://www.prorallypix.com/RX-7/rx11.html
Rod Millen rx7 rally car i believe was 4wd.

Alucard454: yes definately going to do a turbo fuel injected 12A because I need a drivable 200-250hp.

diedxjustxyesterday: I seriously considered making my 1st and 2nd gen into AWD but the amount of engineering required was somewhat daunting to say the least. Even then not sure it would be very competitive.

The Impreza I bought was a 1998 with an automatic trans. This week I picked up a manual trans for it from a 2001 Subaru Forester. This has the 4.111 front differential that matches the rear diff ratio on the auto Impreza. 5 speed Imprezas normaly have 3.9:1 rear end while the autos have 4.111:1.
Things I have learnt since purchasing manual trans:
1) the subaru clutch disc is 8 7/8" diameter with a 24 spline hub. 13B uses same diameter (but 22 spline) so just need to run a subaru clutch disc with a 12A flywheel. Have a light aftermarket flywheel counterweight setup that should do the trick!
2) the trans input shaft extends about 1 1/8" out past the trans bell housing face. About an inch longer than the Mazda. This means when the eng/trans are put together the input shaft splines contact the end of the eccentric shaft when there is still 1 inch gap between the trans and the back of the 12A.
3) the Subaru trans input shaft pilot bearing ID is about 1/2" which is smaller than the Mazda
4) the Subaru "bell housing" is very shallow compared to the mazda. This means the bell housing will not accomodate the Mazda flywheel/clutch assembly if the engine is pushed all the way up to the trans. Fortunately an adapter plate of the appropriate thickness takes care of this.

So right now I need to decide how best to deal with the long input shaft and smaller pilot bearing. Having a 1 inch thick adapter plate would work but that is heavy and pushes the engine further forward and closer to the radiator. Material could be ground out of the inside of the eccentric shaft and off the input shaft splines to get more clearance. Also the input shaft could easily be shortened and at the same time made to accomodate the larger mazda input shaft pilot bearing, this could be the best option.

But first I need to ensure where the entire clutch release mechanism will work best in relation to the thickness of the engine to trans adapter plate. And ensure the shallow Subaru bell housing will accomodate the Mazda flywheel clutch assembly.

But otherwise it is going very well

I hope this helps you with your build :)
http://cp_www.tripod.com/rotary/pg04.htm

Holy E=MC2 man, this is a cool science project. A pleasure to follow!

I got my hands on a very used subaru pressure plate and clutch plate. Interestingly the pressure plate hole pattern matches the mazda flywheel only difference is the dowel holes are smaller. I don't think the Subaru pp will work without modifications to the flywheel as the distance between the clutch face on the pp and pp bolt face is different to the mazda pp so clamping force may be too weak.
The pilot bearing needs to have an OD of 20mm and an ID of 12mm. There are needle rollers available that are 12mm x 19mm so maybe using .5mm shim stock could locate the bearing in the e-shaft.

"I hope this helps you with your build
http://cp_www.tripod.com/rotary/pg04.htm"
Thank you that LongsturboFB is interesting

When using needle bearings on non-hardened shafts it is required to use a "liner". Liners are normally thin wall and press fit onto the shaft with a ground OD.

Not saying the input shaft in not hardened but it shows engineering precedent to shim the ID rather than the OD. So you may want to look into going up to the 20MM OD x 14MM ID needle bearings and find or manufacture a 14MM OD x 12MM ID liner to press onto the input shaft.

Kick ass project by the way.

-billy

All the best with your project. Looking forward to seeing the finished product...

Great stuff, cant wait to see this progress

Impreza
 

Finally an Imprezza gets a real Motor, Good work, I love it!

Nice
 

I thought about this Mod myself , Very good, I may look for a Subie Aswell.

is that a 2.5 rs impreza?? man thats sick rotarys can drop in an impreza awd thats sick

im excited for you dude....and jealous lol.

what tranny you are planning to use? if you going turbo you should consider a STI one it have a 3.90 final gear but the MY04-06 have short gears, wrx and n/a some have weak gears and some have weak input shaft. i see ppl blowing them left and right. other than that is a cool project. i would like to see it when finished

Awesome project Bruce! Can't wait to see this baby in person.

If you are short on clearance between the fan shroud and the nose of the water pump, maybe you could consider using 1st gen MR2 efans. This is a twin fan setup, and you can position it so that the nose of the water pump sits between the two fans.

Best of luck. I will be watching your progress. :)




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wow
 

I thought it was imposible , Good luck withy the build :nod::icon_tup:

I have gotten the clutch pilot bearing sorted out. Used a 19mm OD needle roller bearing inside a sleeve with the correct ID for the subie trans. The input shaft which runs inside the needle roller, best I can tell is hardened. If I could have found a needle roller with the right size inner liner I would have used it over the shaft.
I'm doing a lot of measuring right now of the positions of the dowel pins on both the engine and transmission. Want to have the adapter plate done by the end of the month.

I have one of the original Kennedy engineering adapter plate/flywheel setups to mate a rotary to a scoob transaxle. I picked it up planning a very similar project. I can take a few pics if you want to get an idea of how they engineered the mount plate and flywheel issues.


Isaac

Yes please post pictures and if you wanted to sell it I'd be interested. What year subie trans was it made for? I have not seen such a thing on Kennedy's website