auxilary Posted November 23, 2003 Share Posted November 23, 2003 Today my friend Rob and I decided to attempt a trial fit and see about making mock mounts for the rotary in my Z. He's the guy hiding behind the motor. We bolted up an rx7 tranny to the motor, and figured we'd give it a go. the beast. twin turbo 2 rotor cosmo engine. Mistake #1: turns out it would've been better if we disconnected the transmission and jacked it up from underneath. But this worked ok in our favor, tranny went in more or less, and we got a good estimate where the motor would sit. This tranny is 3 feet long, and weighs about 100lbs. You can see the oddball mounts on the bottom of the block. It's very wide with all of the crap attached. This is where problems start. As you can see, it's about to clip the hood latch, and that's where the throttle cable goes. So, hood latch is going to be deleted. This is almost hte final position of hte motor, except it will be about 8" lower than current position Shifter hole and tranny lined up Oil filters on rotaries are in the rear, and if you can see the 2 little bolt holes, that's where the clutch slave mounts, and the clutch fork is on the top Close to final positioning, the motor needs to come down a bit to clear the hood and etc. Problem #2: the waste gate for one of the turbos hits the stock motor mount, the other reason we couldn't lower it. Tranny about 3" lower than where it should be, we lifted it up a bit to be in place, it fit, but I forgot to take a better picture. Comparison of front crossmember and the stock placement of rotary mount. I was brilliant enough to slip and twist my ankle, which is killing me at the moment, so we cut short, plus it was getting late. We will be doing another trial fit, this time with motor's intake manifolds and turbos removed, and making mock mounts to achieve reality. The motor sits more forward than I anticipated, and I may even be able to use the stock crossmember to run mounts off of, something like Alsil's ford setup with custom mounts to the rotary (in different place, middle of the block. Downside is sacrificing AC ) Full size pictures can be found HERE Quote Link to comment Share on other sites More sharing options...
Sparky Posted November 23, 2003 Share Posted November 23, 2003 Awesome! it really doesnt look to be all that painful of a swap, looks alot easier than i thought it would be...but what do I know, I'm not the one doing to work! Thats going to be so nice when you get it going. are you going to do any detail work to the engine compartment? make it as shiny and nice as the outside? -S Quote Link to comment Share on other sites More sharing options...
auxilary Posted November 23, 2003 Author Share Posted November 23, 2003 yup. I'll clean and paint it, but this was just done to do a test fit, so if i scraped some paint, no biggie. Quote Link to comment Share on other sites More sharing options...
Tim240z Posted November 23, 2003 Share Posted November 23, 2003 Great Alex!!! Keep the updates coming. I'm following this one with great interest! Tim Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted November 23, 2003 Share Posted November 23, 2003 I'll be watching this one with much interest... but I wince a little too. Rotaries have just always seemed like more trouble than their worth to me, with all the dozens and dozens of vacuum hoses, etc... complicated stuff, and I always hear how they are 100% intollerant of ANY detonation... which really seems like it would be a HUGE concern if you're trying to get big hp numbers out of a twin turboed motor... I mean wont you need to be SUPER careful? Also... around here at least, parts for them are scarce, and if you needed to have one rebuilt... forget it. Even though have like all of two moving parts (heheh I'm exaggerating but you get my drift) they actually run two to three times MORE to have rebuilt than a Z engine does! It all comes down to reliability... another example would be the twin turbo rotary last gen RX-7's... it's a pretty well known fact that these cars are notorious for being problematic, and warranty claims KILLED Mazda on that car... And in general people I"ve known who owned RX-7's turbo or not always give the impression that they are very unreliable cars, and that 100k miles is the most they go w/o serious engine issues (serious oil leaks being the most common related to me). I'm not trying to be a downer here... really I'm not!! I think this is one of the coolest ideas I've seen for a swap in a long time, but I AM curious, why are you going with this particular choice? For all (admittedly percieved, not necessarily factual) disadvantages, the only advantage I would think there could be would be weight savings, which would probably be minimal at best. So... why go this route? Quote Link to comment Share on other sites More sharing options...
auxilary Posted November 23, 2003 Author Share Posted November 23, 2003 simple: no one has one Quote Link to comment Share on other sites More sharing options...
Dan Juday Posted November 23, 2003 Share Posted November 23, 2003 Nice to see some PROGRESS Alex. But what does this have to do with CONGRESS? Quote Link to comment Share on other sites More sharing options...
Guest Rotary Racer Posted November 23, 2003 Share Posted November 23, 2003 I'll be watching this one with much interest... but I wince a little too. Rotaries have just always seemed like more trouble than their worth to me' date=' with all the dozens and dozens of vacuum hoses, etc... complicated stuff, and I always hear how they are 100% intollerant of ANY detonation... which really seems like it would be a HUGE concern if you're trying to get big hp numbers out of a twin turboed motor... I mean wont you need to be SUPER careful? Also... around here at least, parts for them are scarce, and if you needed to have one rebuilt... forget it. Even though have like all of two moving parts (heheh I'm exaggerating but you get my drift) they actually run two to three times MORE to have rebuilt than a Z engine does! It all comes down to reliability... another example would be the twin turbo rotary last gen RX-7's... it's a pretty well known fact that these cars are notorious for being problematic, and warranty claims KILLED Mazda on that car... And in general people I"ve known who owned RX-7's turbo or not always give the impression that they are very unreliable cars, and that 100k miles is the most they go w/o serious engine issues (serious oil leaks being the most common related to me). I'm not trying to be a downer here... really I'm not!! I think this is one of the coolest ideas I've seen for a swap in a long time, but I AM curious, why are you going with this particular choice? For all (admittedly percieved, not necessarily factual) disadvantages, the only advantage I would think there could be would be weight savings, which would probably be minimal at best. So... why go this route?[/quote'] Hello I am the one behind the motor. I understand your hesitation about the rotary. But let me see it I can shed some light on any problems and or questions that you may have (and you can ask more if you have any). We are going to be using an after market engine management system and removing the smog equipment off the motor. This will lead to a very few amount of vacuum lines on the motor. Also we will be using silicone hose that can withstand greater heat than your standard rubber can. One reason that led to the break down of the rubber vacuum lines on the 3rd generation RX-7 was two fold (some say more but these are the basic ones). One was the 13B-REW that was put into the 3rd generation was crammed into much smaller of a space and heat exchange and engine bay temps became a problem and the rubber hose broke down. Mazda fixed this in the 1996 FD (by chaning the vacumm lines) but by this time It was not sold here in the states any more. Another problem was the pre cat on the exhaust also contributed to the extra heat in the engine bay. Due to the increased HP on the REW the extra fuel that was added caused this pre-cat to clog early leading to higher engine bay temps and also to much back pressure casing the turbos to go and engines as well. Mazda also fixed this problem in 96’by using a down pipe. For our case like I said before all emission equipment will be removed. You are right when you say they do not fair well to detonation. There is a small about they can take but mot much. When tuning these motors a deferent attention to detail is taken. I have always said that the true rotary enthusiast is slightly more anal about tuning and car care then your standard gear head, it just comes with the territory. Big HP #’s are achievable but in this situation we are not looking to be a “Supra dyno queen†With the stock motor and even stock turbos the HP #’s Alex is looking for are very attainable and safe with the aid of an after market engine management system. As to regards to it being expensive, parts being scarse, and finding people to work on it this situation is slightly different. I will re-build the motor if the time ever comes to it and I have just a light hook up on parts so no worries there. Come look at my garage and you will see . I think I have rambled on for enough. Any more question fire away. - Dana Robert Osborn Jr. Quote Link to comment Share on other sites More sharing options...
blueovalz Posted November 23, 2003 Share Posted November 23, 2003 Keep the pictures coming as I like any documentation on swaps as unique as this one. I am surprised in the length of this motor and always assumed them to be very short. To see the what appears to be a complete use of space between the crossmember and the fireway surprised me. Quote Link to comment Share on other sites More sharing options...
Jumbo240ez Posted November 24, 2003 Share Posted November 24, 2003 Looks fantastic Aux! Also looks like you're making great progress and it'll be done in no time. Jon Quote Link to comment Share on other sites More sharing options...
PETEW Posted November 24, 2003 Share Posted November 24, 2003 I've always been an RX-7 fan. I would love to own a Roatary turbo car one day. Too bad most of them are beat to hell. Good luck on the swap, I can't wait to see it run. Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted November 26, 2003 Share Posted November 26, 2003 when i win the lottery i want a 20b turbo in my zthink i am going to have to settle for a ford 5.0 instead. Quote Link to comment Share on other sites More sharing options...
auxilary Posted November 26, 2003 Author Share Posted November 26, 2003 see the forsale forum, i have a link there just for you, randy Quote Link to comment Share on other sites More sharing options...
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