EJ20 + 90 RX-7 + Ford 9" = ?

Tinywagon · 08-26-2008, 11:40 PM

Sooo, I know that this will strike a nasty chord with some folks so if the mood strikes you, then flame away.

It's just occured to me that I've got quite a few parts laying around that could meld together into something interesting.

I've just found an EJ20 from an 02 wrx in the scrap yard across the street from my house, I've got a 1971 ford F100 that was living in my yard when I moved into my house with a 9" rear can be trimmed down to fit under a 1990 Mazda Rx7 that is also sitting in my yard.

So i'm curious, I've looked around on all the conversion forums and I think that all of these incredients can be melded into one cohesive form.

I've done a good deal of research, but I think that there are a few questions that remain unanswered.

1. With a rebuilt 9" ford, will that rear end sap too much power from the EJ20 if attached via a mazda five speed trans that was originally from the mazda.

which leads me to the 2nd question

2. In order for the EJ20 and the mazda TII five speed to mate properly, would it be better to rework the bellhousing or machine an adapter plate?

I also really want to know what you guys think about this, pro or con.

thanks in advance

* Registered users of the site do not see these ads.

parkes · 08-27-2008, 01:53 AM

If you want to do it, anything can be done, Get the moter before its goneeee

Tinywagon · 08-27-2008, 01:39 PM

so with I called the scrap yard and they said that they had the EJ20 for about $1000 if I pulled it. I can do that. I think that it's a good price and i think i'm going to pick it up at the end of the week.

Jaxx · 08-27-2008, 03:12 PM

pull EVERY wire you can everything behind the dash ...

parkes · 08-27-2008, 04:43 PM

yaperoo

Patrick Olsen · 08-28-2008, 12:58 AM

I would think the 9" is heavy/overkill for this. Lightweight car and relatively non-torquey engine (compared to the sort of torque a 9" can handle). Maybe find a Mustang 8.8" rear? Those are certainly plentiful, and can handle plenty of power.

Pat Olsen

noisycricket · 09-01-2008, 03:32 PM

Expect to do a lot of work in the engine bay to get the flat four to fit. The RX-7 bay is shaped... weird. Or rather the Subaru bay is shaped weirder.

You'll probably have to move the trans forward or hack the firewall. Moving the trans is easier.

You will probably not break the Mazda rear so I'd leave it alone. People run them with GenIII Chevy engines... they do break when you launch wheels-up on drag radials on your way to 12 second passes

but for the most part they're pretty tough. It's essentially the same rear as used in the S2000 as well as pretty much every RWD Mazda except for V6 trucks, turbo cars, and the RX-8. If you need beef, the one from a turbo model is bigger, a bolt-in, and you will *not* break it until the 700hp and launching on slicks level. Plus you won't have to worry about all the floor hackery needed to convert the thing to solid axle. You'll have enough fun trying to get the Subaru engine down between the framerails.

PS - If you want to strike a nasty chord, go to one of the RX-7 forums and talk about your swap. Some people seem to love the engine and hate the car since they say an engine swap ruins it.

Tinywagon · 09-01-2008, 04:41 PM

Yeah i've been thinking about the rear end swap and It'll probably just be easier to put a turbo rear in from an FC TII. I think i know where to get one. But as far as moving the trans. I think that it'll be easier to do that. However , I'm not sure if you guys have seen an FC engine bay recently but that is a very large space compared to the bay on my wrx.

And I think i will start a thread on RX7club.com i've already got a profile there.

Ah, I can feel their hate washing over me already! I'll link to the thread after i've made it.

Tinywagon · 09-01-2008, 06:59 PM

They've been pretty supportive thusfar, but I have a feeling that the haters are on their way.
http://www.rx7club.com/showthread.php?t=783684

If you're interested.

noisycricket · 09-01-2008, 07:44 PM

The last time I dug into an FC it seemed like the entire crossmember was narrower than a Subaru engine. I know they have wide engine bays to clear the bottom-wide rotary, but the Subaru bay flares out quite a bit forward of the front wheels, where the engine actually sits.

I had been thinking about this very swap before, actually. Subaru engines weigh a LOT less than a rotary, and coincidentally enough the clutch is the same diameter as a N/A RX-7 so that situation would be squared away. (Push type Subaru pressure plate and RX-7 N/A disc) The clutch fork would be in the way of the Subaru starter. I have a collection of Mazda flywheels as well as a WRX flywheel, and I don't think they're the same size, BUT it looks like it'd be easy-peasy to whip up an adapter to mount a lightweight rotary flywheel to the Subaru engine, given that the inside diameter of one is larger than the OD of the mating flange on the back of a Subaru crank.

The steering shaft would be in the way in an FC. The steering box definitely in the way in an FB, unless you move the engine way forward into where the radiator goes, at which point you may as well notch the framerails and use the entire Subaru transmission complete with the front drive axles... and then use a modified Subaru crossmember, eliminating the reason why you had to move it so forward in the first place, but it'd sure be neat

Tinywagon · 09-01-2008, 08:22 PM

Hmmm. an AWD rx7...sounds cool. and i could get a six speed setup out of it if I decided to source an STi setup.

I hadn't thought about that, I figured it would be too much work. but hell in for a penny in for a pound.

eastcoastbumps · 09-01-2008, 10:11 PM

A 4g63 would be easier. It would bolt right up to your trans.

noisycricket · 09-03-2008, 08:40 PM

No it wouldn't. It might bolt up to a Turbo model's trans, if you can source a rare Mazda truck bellhousing from the couple years that they used a MitsuMill. ('87-88 2.6l, yeah just find a 20 year old Japanese truck anymore...) But then you'd have a Mitsubishi engine... eew. And you'd still have to source a Turbo transmission (getting harder to find 'cos all the drag guys keep blowing them up... and the N/A transmissions blow up over about 120ft-lb of torque and anyway they don't have a replacable bellhousing)

The main problem with the AWD thing would be the need to make new fenders after relocating the strut towers and front wheel centerline aft, and then all the holes in the body to put the radiator in the back... and then you need a place to put the fuel tank.

Ain't it a bitch?

Tinywagon · 09-04-2008, 06:38 PM

yeah,

the AWD thing was more of a pipe dream. I'm not so sure that it could fit without REDICULOUS modification. but I still think that the EJ would fit pretty well if it were an RWD kinda thing.

Wiring's gonna be a biatch though. I may just end up hotrod wiring the whole damn thing and using a stand alone.

08-26-2008, 11:40 PM	#1
Tinywagon Scooby Newbie Member#: 157566 Join Date: Aug 2007 Chapter/Region: SWIC Location: Santa Fe Vehicle: 2002 WRX wagon Aspen White	EJ20 + 90 RX-7 + Ford 9" = ? Sooo, I know that this will strike a nasty chord with some folks so if the mood strikes you, then flame away. It's just occured to me that I've got quite a few parts laying around that could meld together into something interesting. I've just found an EJ20 from an 02 wrx in the scrap yard across the street from my house, I've got a 1971 ford F100 that was living in my yard when I moved into my house with a 9" rear can be trimmed down to fit under a 1990 Mazda Rx7 that is also sitting in my yard. So i'm curious, I've looked around on all the conversion forums and I think that all of these incredients can be melded into one cohesive form. I've done a good deal of research, but I think that there are a few questions that remain unanswered. 1. With a rebuilt 9" ford, will that rear end sap too much power from the EJ20 if attached via a mazda five speed trans that was originally from the mazda. which leads me to the 2nd question 2. In order for the EJ20 and the mazda TII five speed to mate properly, would it be better to rework the bellhousing or machine an adapter plate? I also really want to know what you guys think about this, pro or con. thanks in advance * Registered users of the site do not see these ads.

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08-27-2008, 01:53 AM	#2
parkes Scooby Specialist Member#: 166898 Join Date: Dec 2007 Chapter/Region: W. Canada Location: Canada Vehicle: 1994 T leg SS ABM	If you want to do it, anything can be done, Get the moter before its goneeee

08-27-2008, 01:39 PM	#3
Tinywagon Scooby Newbie Member#: 157566 Join Date: Aug 2007 Chapter/Region: SWIC Location: Santa Fe Vehicle: 2002 WRX wagon Aspen White	so with I called the scrap yard and they said that they had the EJ20 for about $1000 if I pulled it. I can do that. I think that it's a good price and i think i'm going to pick it up at the end of the week.

08-27-2008, 03:12 PM	#4
Jaxx NASIOC Supporter Member#: 177 Join Date: Aug 1999 Chapter/Region: NWIC Location: Boise,Idaho,USA Vehicle: The 93 Imp W/EJ20K flat black	pull EVERY wire you can everything behind the dash ...

08-27-2008, 04:43 PM	#5
parkes Scooby Specialist Member#: 166898 Join Date: Dec 2007 Chapter/Region: W. Canada Location: Canada Vehicle: 1994 T leg SS ABM	yaperoo

08-28-2008, 12:58 AM	#6
Patrick Olsen NASIOC Supporter Member#: 120 Join Date: Jul 1999 Chapter/Region: AKIC Location: Where the Navy sends me... Vehicle: 1997 Legacy 2.5GT QuickSilver Metallic	I would think the 9" is heavy/overkill for this. Lightweight car and relatively non-torquey engine (compared to the sort of torque a 9" can handle). Maybe find a Mustang 8.8" rear? Those are certainly plentiful, and can handle plenty of power. Pat Olsen

09-01-2008, 03:32 PM	#7
noisycricket Scooby Newbie Member#: 148043 Join Date: May 2007	Expect to do a lot of work in the engine bay to get the flat four to fit. The RX-7 bay is shaped... weird. Or rather the Subaru bay is shaped weirder. You'll probably have to move the trans forward or hack the firewall. Moving the trans is easier. You will probably not break the Mazda rear so I'd leave it alone. People run them with GenIII Chevy engines... they do break when you launch wheels-up on drag radials on your way to 12 second passes but for the most part they're pretty tough. It's essentially the same rear as used in the S2000 as well as pretty much every RWD Mazda except for V6 trucks, turbo cars, and the RX-8. If you need beef, the one from a turbo model is bigger, a bolt-in, and you will not break it until the 700hp and launching on slicks level. Plus you won't have to worry about all the floor hackery needed to convert the thing to solid axle. You'll have enough fun trying to get the Subaru engine down between the framerails. PS - If you want to strike a nasty chord, go to one of the RX-7 forums and talk about your swap. Some people seem to love the engine and hate the car since they say an engine swap ruins it.

09-01-2008, 04:41 PM	#8
Tinywagon Scooby Newbie Member#: 157566 Join Date: Aug 2007 Chapter/Region: SWIC Location: Santa Fe Vehicle: 2002 WRX wagon Aspen White	Yeah i've been thinking about the rear end swap and It'll probably just be easier to put a turbo rear in from an FC TII. I think i know where to get one. But as far as moving the trans. I think that it'll be easier to do that. However , I'm not sure if you guys have seen an FC engine bay recently but that is a very large space compared to the bay on my wrx. And I think i will start a thread on RX7club.com i've already got a profile there. Ah, I can feel their hate washing over me already! I'll link to the thread after i've made it.

09-01-2008, 06:59 PM	#9
Tinywagon Scooby Newbie Member#: 157566 Join Date: Aug 2007 Chapter/Region: SWIC Location: Santa Fe Vehicle: 2002 WRX wagon Aspen White	They've been pretty supportive thusfar, but I have a feeling that the haters are on their way. http://www.rx7club.com/showthread.php?t=783684 If you're interested.

09-01-2008, 07:44 PM	#10
noisycricket Scooby Newbie Member#: 148043 Join Date: May 2007	The last time I dug into an FC it seemed like the entire crossmember was narrower than a Subaru engine. I know they have wide engine bays to clear the bottom-wide rotary, but the Subaru bay flares out quite a bit forward of the front wheels, where the engine actually sits. I had been thinking about this very swap before, actually. Subaru engines weigh a LOT less than a rotary, and coincidentally enough the clutch is the same diameter as a N/A RX-7 so that situation would be squared away. (Push type Subaru pressure plate and RX-7 N/A disc) The clutch fork would be in the way of the Subaru starter. I have a collection of Mazda flywheels as well as a WRX flywheel, and I don't think they're the same size, BUT it looks like it'd be easy-peasy to whip up an adapter to mount a lightweight rotary flywheel to the Subaru engine, given that the inside diameter of one is larger than the OD of the mating flange on the back of a Subaru crank. The steering shaft would be in the way in an FC. The steering box definitely in the way in an FB, unless you move the engine way forward into where the radiator goes, at which point you may as well notch the framerails and use the entire Subaru transmission complete with the front drive axles... and then use a modified Subaru crossmember, eliminating the reason why you had to move it so forward in the first place, but it'd sure be neat

09-01-2008, 08:22 PM	#11
Tinywagon Scooby Newbie Member#: 157566 Join Date: Aug 2007 Chapter/Region: SWIC Location: Santa Fe Vehicle: 2002 WRX wagon Aspen White	Hmmm. an AWD rx7...sounds cool. and i could get a six speed setup out of it if I decided to source an STi setup. I hadn't thought about that, I figured it would be too much work. but hell in for a penny in for a pound.

09-01-2008, 10:11 PM	#12
eastcoastbumps Scooby Guru Member#: 29201 Join Date: Nov 2002 Chapter/Region: NESIC Location: Shrewsbury, MA Vehicle: BMW M3 Honda S2000x2	A 4g63 would be easier. It would bolt right up to your trans.

09-03-2008, 08:40 PM	#13
noisycricket Scooby Newbie Member#: 148043 Join Date: May 2007	No it wouldn't. It might bolt up to a Turbo model's trans, if you can source a rare Mazda truck bellhousing from the couple years that they used a MitsuMill. ('87-88 2.6l, yeah just find a 20 year old Japanese truck anymore...) But then you'd have a Mitsubishi engine... eew. And you'd still have to source a Turbo transmission (getting harder to find 'cos all the drag guys keep blowing them up... and the N/A transmissions blow up over about 120ft-lb of torque and anyway they don't have a replacable bellhousing) The main problem with the AWD thing would be the need to make new fenders after relocating the strut towers and front wheel centerline aft, and then all the holes in the body to put the radiator in the back... and then you need a place to put the fuel tank. Ain't it a bitch?

09-04-2008, 06:38 PM	#14
Tinywagon Scooby Newbie Member#: 157566 Join Date: Aug 2007 Chapter/Region: SWIC Location: Santa Fe Vehicle: 2002 WRX wagon Aspen White	yeah, the AWD thing was more of a pipe dream. I'm not so sure that it could fit without REDICULOUS modification. but I still think that the EJ would fit pretty well if it were an RWD kinda thing. Wiring's gonna be a biatch though. I may just end up hotrod wiring the whole damn thing and using a stand alone.