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cdmcse
Is anyone familiar with the RX-8 Motor? I was considering it for a swap.

Anyone know if the bolt pattern is the same as older rotary motors?

It seems like it would be fun engine in the 914.
Rand
Hmmm... .Looking forward to some replies.

Rotary swaps have been done. Although it's tough to find much in the way of documented progress. Here is one resource.

I almost went that route because my buddies have made crazy power cheaply with them. They ruled the Corvallis OR AX scene for a couple years in a "beater" RX3.

I love the rotaries. But I want more torque. I am thinking about building a super-light "Locost" (Lotus 7) project with a tear ported 13b. I think that fits well. Say 200ish HP in a super-light car with a super-short motor that can be positioned well for weight distribution.

As far as the RX8 itself... I was personally disappointed... Mazda drops the RX7, and finally comes out with the RX8, all the expected hype... all the hopes of crazy new rotary power... and it turned out to be a bit of a let down. While it has potential, I think it should have had more power out of the box.

Every time this comes up, I like to ping the rotary guys. There is rotary 914 talk here and there, but I wish there were more results. Soloracer is working on a killer tri-rotor project... It has sick potential, but the progress pings aren't returning. Hopefully we'll hear about the progress someday.

After all my thoughts on this, I have temporarily concluded that there are only three logical choices for big power in a 914 with a reasonable swap project.

1. RAT big four
2. Subaru
3. V8

Your driving style and budget determine your choice pretty easily.
Crazyhippy
hijacked.gif

There is a Red Rotary powered 7 (superformance) just across the bay from you (Port Townsend). Massive ports, sticky tires, it was a BLAST to drive.

If you happen to run accross it, tell the owner that BJ (from Renegade) says HI.

BJH driving.gif

QUOTE(Rand @ Aug 23 2006, 03:33 PM) *

Hmmm... .Looking forward to some replies.

Rotary swaps have been done. Although it's tough to find much in the way of documented progress. Here is one resource.

I almost went that route because my buddies have made crazy power cheaply with them. They ruled the Corvallis OR AX scene for a couple years in a "beater" RX3.

I love the rotaries. But I want more torque. I am thinking about building a super-light "Locost" (Lotus 7) project with a tear ported 13b. I think that fits well. Say 200ish HP in a super-light car with a super-short motor that can be positioned well for weight distribution.

As far as the RX8 itself... I was personally disappointed... Mazda drops the RX7, and finally comes out with the RX8, all the expected hype... all the hopes of crazy new rotary power... and it turned out to be a bit of a let down. While it has potential, I think it should have had more power out of the box.

Every time this comes up, I like to ping the rotary guys. There is rotary 914 talk here and there, but I wish there were more results. Soloracer is working on a killer tri-rotor project... It has sick potential, but the progress pings aren't returning. Hopefully we'll hear about the progress someday.

After all my thoughts on this, I have temporarily concluded that there are only three logical choices for big power.

1. RAT big four
2. Subaru
3. V8

Your driving style and budget determine your choice pretty easily.

Rotary'14
I do believe the transmission bolt pattern is the same for all the rotary engines. 12A or 13B. So a Kennedy kit should work with the newer renesis 13B. A renesis engine swap would be really fun car, but it would lose in some HP shoot outs against the V8 or turbo Subie, but you can rev to 8500+ and that's ALOT of fun. The renesis engine is mazda's attempt at making a "fuel efficient" clean burning rotary. I've heard that the older 13Bs when modified are capable of higher HP numbers than the renesis, but that was early on, I'm not sure about now.

Exhaust for a non renesis 13B will need to be heavy duty,, but can be much lighter for a renesis due to exhaust port design. Not much if any power can be had by adding a header to the renesis, so the stock exhaust manifold will simplify the exhaust plumbing.


For the easiest swap with a rotary, you will need a GSL-SE front cover (because the engine mounts bolt to this) and any early 13B oil pan. You can then use some angle iron and make a very simple engine mount with the stock bar. It's WAY EASIER than many subie mounts I've seen.

Try to use the whole renesis intake and ignition if you can get it,, it's very efficient.

I love my rotary engine, but in light of all power a Subie makes,,,, I want a ride in a turbo subie so I can get a feel. My 13B streetport makes 220+ HP

Ask me any questions you want about rotary stuff. drunk.gif

-Rob
bd1308
So how fuel efficient are we talking?

My buddy had a turbo II and it got great mileage--13 mpg.

I though I was going to throw up.

Great performance, but I was looking for the gas pouring through his engine, and that wallet that was always empty

LOL

Then he blew his apex seal and lost $1000 in the car, selling it as-is.

Whatever
cdmcse
I thought the renisis rotary would be a good fit to use with a stock 901 tranny. Decent stock HP (240), but not a lot of tranny breaking torque. I think it would be a fun combo.

I would plan on using stock intake and exhaust, providing it fits. I've looked at the engine bay in the RX-8 and it looks like it would fit pretty good.

Do you think It is possible to put the radiator in the engine bay like the subie guys are doing?

Anyone have a pic of a rotary install from the bottom on a lift or something?
cdmcse
QUOTE(bd1308 @ Aug 23 2006, 10:58 PM) *

So how fuel efficient are we talking?

My buddy had a turbo II and it got great mileage--13 mpg.

I though I was going to throw up.

Great performance, but I was looking for the gas pouring through his engine, and that wallet that was always empty

LOL

Then he blew his apex seal and lost $1000 in the car, selling it as-is.

Whatever


The EPA rating is 18 city 22 highway, but fuel economy isn't my primary goal here.
Rotary'14
QUOTE(bd1308 @ Aug 23 2006, 07:58 PM) *

So how fuel efficient are we talking?

My buddy had a turbo II and it got great mileage--13 mpg.

I though I was going to throw up.

Great performance, but I was looking for the gas pouring through his engine, and that wallet that was always empty

LOL

Then he blew his apex seal and lost $1000 in the car, selling it as-is.

Whatever



I got about 25mpg in my 914 when my car was running,,,,, but I was trying to keep be gentle with the go pedal. I'd imagine the renesis should do better under similiar driving conditions. As for the renesis making 240 HP,,,,, didn't mazda get into trouble over their inflated HP figures for that engine?
Rotaries really shine when you turbo them,, but they generate soooo much heat! I'm sure it will take some serious cooling to keep a turbo motor happy,, but I think somebody on the board DID have a street driven turbo rotary 914.

When I get the chance,, I'll slide under my jack stand queen and snap a pic of the engine mounted in my car from below,, you might shoe horn a radiator in there,, good luck with that.

-Rob
Brett W
Might want to make sure you don't get one of these engines.



Mazda expects to recall RX-8s

Source: Automotive News
Automaker: Engines failing vacuum test must be replaced


MONTEREY, Calif. -- After suffering a black eye from disclosing that it won't count RX-8 owners' opinions in its internal customer-satisfaction scores, Mazda says it may have to replace the engines in many of its flagship sports cars.


The voluntary recall of all 2004 and 2005 vehicles, and some 2006s, is expected to be announced this week or next. It involves damage to the catalyst resulting from oil leaks in the RX-8's rotary engine.


Any engine that does not pass a vacuum test must be replaced, said Robert Davis, head of product development and quality at Mazda North American Operations.


Engines prone to failing the test are mostly in hot climates and use synthetic oils.


Mazda also will check each RX-8's battery and starter, which tend to fail in cold climates.


"We're going to give these cars the white-glove treatment," Davis said. "We would rather replace the engine than have the dealer crack them open."


Davis would not disclose the projected failure rate of the engines or the cost to replace them.


Mazda has a remanufacturing center in North Carolina that will rebuild faulty engines and return them to service.


The recall comes after a video Webcast by two dealers who attended the July 11-13 National Dealer Advisory Council meetings in Newport Beach, Calif., was leaked on the Internet.


In the video, dealers said problems with the RX-8 were unfairly lowering Mazda customer-satisfaction scores.


Mazda informed the dealers that RX-8 owners would continue to be surveyed, but that the responses would not factor into dealer
customer-satisfaction scores. See story here


Mazda has issued service bulletins on such trouble spots as squeaky
brakes and engine flooding.

cdmcse
QUOTE(Brett W @ Aug 24 2006, 12:02 AM) *

Might want to make sure you don't get one of these engines.



Mazda expects to recall RX-8s

Source: Automotive News
Automaker: Engines failing vacuum test must be replaced

SNIP


Well, I must admit that is troubling. Anyone own an RX-8? Have you seen issues with your car?
drive-ability
I had a 93 Rx7, Twin turbo, did make a lot of power. Its a beautiful body but I didn't like the power curve. If one put that engine in a 914 it would fly. My V8 is much faster than my 7 and gets better gas mileage. Rotary engines need a lot of fuel to run. I got maybe 12 mpg, now I get 20 in my V8 car.
The rotary engine is much less forgiving run it lean and its time for a rebuild. I had two engines and sold the spare rotors for 600 dollars. Parts are pricey...
Having said that it was the best handling car I have ever driven.
Now install a 20B, 3 rotor and you would have a monster. The Rx8 motor only puts out around 220 hp along with getting poor fuel mileage, a stock twin turbo about 260, change a few things and your a 300 quick. It would be a nice match to the 901 trans because it really has no torque and loves to rev-up to 8K in a second.
I at first didn't really like my V8 but since its been tweaked (lots of trial and error) I wouldn't have it any other way, this car is soft riding handles great and flies. If you do a V8 sorting it is the key, get it to run correctly. Once thats achieved you'll never regret it.
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