Have we been doing our 20B swaps the wrong way
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Joined: Oct 2008
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From: Charleston
Have we been doing our 20B swaps the wrong way
Here are some pics I found through another thread that had a link to an RE-Amemiya 20B build. I noticed the engine mounts and sub frame are drastically different from what we use here in the states. But from the look of it this way corrects all the issues we have been dealing with. Ex. Intake too tall, transmission tunnel in my way, Engine doesn't sit in a factory location ect ect. What do you guys think. Personally I like this way better. But I'm probably biased since I tend to think the Japanese know their cars better than we do.
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From: San Francisco, CA
Not sure exactly what you are referencing but judging by those pics, being RHD in Japan, I doubt many of them care about drastically increasing the size of the trans tunnel on what would be our drivers side.
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Joined: Oct 2008
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From: Charleston
http://rextreme.blogspot.com/2011/02...uricane-7.html
The way it seems from the pictures is that they are using some sort of billet engine mount that offsets everything to an almost "factory location" No beating the firewall or need for bump steer from what I can tell.
The way it seems from the pictures is that they are using some sort of billet engine mount that offsets everything to an almost "factory location" No beating the firewall or need for bump steer from what I can tell.
1. There not running a stock tranny. That's why there's no messaging of the fire wall.
2. They are running a custom oil pan or dry sump. My guess is the oil pick-up from the front plate is just behind the rack. This engine still sits nicely over the rack (but still low enough).
3. This engine still doesn't sit back as far as mine because I know for a fact the UIM will never clear the top portion of the firewall with the LIM at it's stock height. This engine DOES'NT sit behind the rack like stock. Another way I can tell is where the alternator is located. I just recently fabbed a 4 point strut tower brace and my front bar actually crosses over top the alternator (just like stock). This engine still sits a little bit forward.

Take a look at the R1 strut tower brace to compare yourself. As you can see, the above 20b strut tower brace is about an 1 1/2" further forward of the tower mounting studs and the alternator is still in front of the brace. Not so with the stock fd engine placement. The R1 brace goes directly across the strut tower studs evenly and the brace crosses over top the alternator.
http://cgi.ebay.com/ebaymotors/RX-7-...b5662c36#v4-39
2. They are running a custom oil pan or dry sump. My guess is the oil pick-up from the front plate is just behind the rack. This engine still sits nicely over the rack (but still low enough).
3. This engine still doesn't sit back as far as mine because I know for a fact the UIM will never clear the top portion of the firewall with the LIM at it's stock height. This engine DOES'NT sit behind the rack like stock. Another way I can tell is where the alternator is located. I just recently fabbed a 4 point strut tower brace and my front bar actually crosses over top the alternator (just like stock). This engine still sits a little bit forward.

Take a look at the R1 strut tower brace to compare yourself. As you can see, the above 20b strut tower brace is about an 1 1/2" further forward of the tower mounting studs and the alternator is still in front of the brace. Not so with the stock fd engine placement. The R1 brace goes directly across the strut tower studs evenly and the brace crosses over top the alternator.
http://cgi.ebay.com/ebaymotors/RX-7-...b5662c36#v4-39
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Joined: Oct 2008
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From: Charleston
Well, I'm not a master fabricator, so I figured I'd ask and eventually I'd get one og you guys to weigh in. Thanks T-Von. So, do you think that concept has any worth?? And does anyone have pics or links to the Greddy Super 7 build????
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
i think its dry sumped. the pump on the side of the motor looks more like a dry sump pump than the PS pump
Of course it does! What these guys are mainly trying to do is push the engine as far back as possible while retaining an unmodified factory intake and NOT moving the rack. If they re-engineeer the LIM like what Autotech did, then they would be able to move it behind the rack and even lower than stock (like where my engine is). The stock LIM is what's limiting everything. The custom LIM is the key if your not trying to hack the firewall. In terms of weight distribution, lower Cg, and polar moment, this is better than your typical 20b swap. Remember 50/50 isn't everything.
There's more to it. What I don't understand is since they basically gutted the entire vehicle and welded all the frame supports, why couldn't they just go ahead an hack the fire wall and duplicate what Cmoniker did since they were dead set on retaining the full factory intake?
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Joined: Oct 2008
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From: Charleston
SO modifying the factory lower intake or making your own manifold would let you get away with the factory subframe and those little puck mounts??? Basically?? And I'm sure you could modify those to pull the engine further back like you have yours right T-Von.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
Of course it does! What these guys are mainly trying to do is push the engine as far back as possible while retaining an unmodified factory intake and NOT moving the rack. If they re-engineeer the LIM like what Autotech did, then they would be able to move it behind the rack and even lower than stock (like where my engine is). The stock LIM is what's limiting everything. The custom LIM is the key if your not trying to hack the firewall. In terms of weight distribution, lower Cg, and polar moment, this is better than your typical 20b swap. Remember 50/50 isn't everything.
There's more to it. What I don't understand is since they basically gutted the entire vehicle and welded all the frame supports, why couldn't they just go ahead an hack the fire wall and duplicate what Cmoniker did since they were dead set on retaining the full factory intake?
There's more to it. What I don't understand is since they basically gutted the entire vehicle and welded all the frame supports, why couldn't they just go ahead an hack the fire wall and duplicate what Cmoniker did since they were dead set on retaining the full factory intake?
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Joined: Oct 2008
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From: Charleston
This RE Amemiya Super Greddy 7 RE20B was built for the annual Tokyo Auto Salon. This exquisite machine is packed with RE Amemiya's tuning knowledge and is setup for the street. The weight distribution of the well balanced FD becomes thrown off. The 20B had to be offset 10cm to the rear and 6cm to the front in reference to the 13B. Also, the body, subframe, and the propeller shaft all need fabrication.
I"m looking at the measurements, and I'm thinking if that's good enough for RE-A ;why not us ?? I'm still looking for pictures of the build to see if they used the same technique.
I"m looking at the measurements, and I'm thinking if that's good enough for RE-A ;why not us ?? I'm still looking for pictures of the build to see if they used the same technique.
you know that's very similar to the way I did mine.


I put the aluminum pucks on the lathe and turned them down so I have less than a .100" clearance between the subframe and the bottom of the motor. I'm running a drysump setup so my pan is perfectly flat. and as you can see the engine sits behind the rack. obviously the firewall has to be hacked up to go this far back but at this point massaging the firewall is the least of my worries.
More pics and full buildup can be found here https://www.rx7club.com/race-car-tech-103/bigals-fd-20b-racecar-project-747809/
BigAl...


I put the aluminum pucks on the lathe and turned them down so I have less than a .100" clearance between the subframe and the bottom of the motor. I'm running a drysump setup so my pan is perfectly flat. and as you can see the engine sits behind the rack. obviously the firewall has to be hacked up to go this far back but at this point massaging the firewall is the least of my worries.
More pics and full buildup can be found here https://www.rx7club.com/race-car-tech-103/bigals-fd-20b-racecar-project-747809/
BigAl...
If you use whatever transmission they are using then yes you can just have the LIM remade so you can re-use the stock subframe. The Fd tranny won't fit with the stock subframe because the bell housing will hit the firewall. The rear portion of the factory subframe wont let the engine sit low enough and has to be modified and droped like mine. Then you can message the firewall and the engine will fit with the stock tranny. I don't know if you saw my thread or not?
https://www.rx7club.com/20b-forum-95/20b-moved-back-pics-info-937928/
And for the ones who want to bolt in a 20b without cutting the ppf, relocating the shifter, and keeping the full factory subframe (which means the steering is stock location too) can purchase our kit. Many ways to skin a cat. Bascially comes down to a lot of custom fab work (slightly better mass location) or buy a kit like ours to avoid bump steer correction.
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Joined: Oct 2008
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From: Charleston
And for the ones who want to bolt in a 20b without cutting the ppf, relocating the shifter, and keeping the full factory subframe (which means the steering is stock location too) can purchase our kit. Many ways to skin a cat. Bascially comes down to a lot of custom fab work (slightly better mass location) or buy a kit like ours to avoid bump steer correction.
^Be prepared to either shorten or remake the oil pan. My factory one has already scraped the ground and has a dent (and my car is at stock ride height. I'm currently fabing a new oil pan out of a nice 1/2" piece of aluminum as we speak. It will be internally baffled. The thick base will act like an engine brace.
^Be prepared to either shorten or remake the oil pan. My factory one has already scraped the ground and has a dent (and my car is at stock ride height. I'm currently fabing a new oil pan out of a nice 1/2" piece of aluminum as we speak. It will be internally baffled. The thick base will act like an engine brace. 

Thread Starter
Joined: Oct 2008
Posts: 1,168
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From: Charleston
^Be prepared to either shorten or remake the oil pan. My factory one has already scraped the ground and has a dent (and my car is at stock ride height. I'm currently fabing a new oil pan out of a nice 1/2" piece of aluminum as we speak. It will be internally baffled. The thick base will act like an engine brace. 







