ShowHBK Posted January 21, 2015 Report Share Posted January 21, 2015 (edited) The dream is simple enough. I want to put a 26B inside an Rx-8 (made from the Renesis housing and not Rx-7 13b housing) that can be used in both the streets and the track (Possible Turbo?). Before we begin, I am well aware of the challenges of this project (insane cost, tuning, parts, etc.). I have a deep passion and a drive for completing this project and I would like to turn to everyone here for project advice, ideas, and any help with getting my project going. This will not be anything that will be completed anytime soon, but I felt like posting this here to get ideas for the project. My goal is to leave the car in the end looking as stock as possible and still retain the back seats (if possible). If at all I would like to leave this as an open discussion about what aspects of the car would need to be changed given the new engine. How would the frame of the car hold up? what type of transmission would have to go in place of the stock one? tires? engine mounts? tuning the engine? oh the list goes on. I have never done a rebuild on a Rotary in my life or done much engine work, but I have been reading plenty of books and have done a great deal of research on this topic and all roads point to the Renesis being a more capable four rotor then the 13b in an RX-7. I would like to hear other opinions though. Where the crap does someone get the parts needed to begin this project? what would step one be in everyone's opinion? I am very interested to hear what people have to say. TL;DR I am going to put a 4 rotor engine in an RX-8 and no one is going to stop me. Edited January 22, 2015 by ShowHBK Quote Link to comment Share on other sites More sharing options...
Green Bastard Posted January 21, 2015 Report Share Posted January 21, 2015 It seems to me the easy part would be getting the housings and irons, the hard part would be getting the manifolds and eccentric shaft, it almost seems to me that those would need to be custom made. Quote Link to comment Share on other sites More sharing options...
Smokey Posted January 21, 2015 Report Share Posted January 21, 2015 http://www.rx7club.com/group-buy-product-development-interest-3rdgen-rx-7-269/defined-autoworks-4-rotor-kit-group-buy-1075028/ Good news: Your solution is local and already has a running example. They've also figured out mounting, ECU, and oiling options. Bad news: it's expensive as shit, and you'll never do it better than them on your own and likely never be cheaper either. I'd be interested to know why you think the renesis parts would be better than 13b stuff for a 4 rotor? Are you not thinking you'd want PP housings? Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 21, 2015 Author Report Share Posted January 21, 2015 (edited) http://www.rx7club.com/group-buy-product-development-interest-3rdgen-rx-7-269/defined-autoworks-4-rotor-kit-group-buy-1075028/ Good news: Your solution is local and already has a running example. They've also figured out mounting, ECU, and oiling options. Bad news: it's expensive as shit, and you'll never do it better than them on your own and likely never be cheaper either. I'd be interested to know why you think the renesis parts would be better than 13b stuff for a 4 rotor? Are you not thinking you'd want PP housings? Oh, I know about these guys. They are a bit down south from where I live but they jammed that thing into an RX-7 in the Video and to my knowledge they have never done an RX-8 before. The hardest part that I know of in terms of engine parts is the center block for a 23b which some people use the center housing from a Cosmo 20b but I do know if you contact Mazda directly they will make and sell a 23b center block that is special made. Also the E-Shaft is VERY expensive from what I understand. My idea behind using the Renesis housing as opposed to the regular 13b is that from my research and understanding the 13b found in most RX-7 is difficult to tune with modern equipment, needs the turbo to get high BHP, weaker housing then the Renesis, and a few other things. My thought process is that the Renesis is in every way an improvement over the old 13b in just about every way and is the logical step in terms of creating the best 23b out there. I know this math is flawed, but the old 13b with a turbo or turbocharger had just as much BHP as the Renesis does without one, so in "theory" (and I use that lightly) the Renesis should develop more BHP then the 13b REW in a 23b engine. (not that BHP is everything) Edited January 22, 2015 by ShowHBK Typo Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 21, 2015 Author Report Share Posted January 21, 2015 It seems to me the easy part would be getting the housings and irons, the hard part would be getting the manifolds and eccentric shaft, it almost seems to me that those would need to be custom made. As for the E-shaft I know of a guy who has worked in the fabrication / metalworking industry for over 30 years and has told me he can make it for me so long as I supply the blueprints and tell him what its made out of. Says he will do it REAL cheap. This could cut down on my cost by a lot imo Quote Link to comment Share on other sites More sharing options...
Smokey Posted January 21, 2015 Report Share Posted January 21, 2015 I'd be really surprised if you could buy ANY parts from the 26b from Mazda let alone an eccentric shaft (it's not a crank shaft). If you find proof of that though please share. The 4 rotors I've seen pics and vids of didn't use any thick irons but instead adapted standard irons to take bearings and support the longer eccentric shaft. The renesis was a step forward and a step back in rotary development. The use of side ports for the exhaust was a compromise to try to keep emissions within specs and is a design compromise. The 26b was definitely peripheral port for both intake and exhaust as that's always how you'll make the most absolute power in a rotary (with the trade off of low end, drivability, and idle). If you're concerned about making the most hp out of your 4 rotor then you'll want to be PP too which will mean drilling any housings you have so starting with renesis parts will just mean you have to do more work for no additional benefit. Quote Link to comment Share on other sites More sharing options...
SHIEF Posted January 21, 2015 Report Share Posted January 21, 2015 Went to HS with Logan, dude knows his rotaries. Think that car has been done for years, irrc. Quote Link to comment Share on other sites More sharing options...
Green Bastard Posted January 21, 2015 Report Share Posted January 21, 2015 As for the E-shaft I know of a guy who has worked in the fabrication / metalworking industry for over 30 years and has told me he can make it for me so long as I supply the blueprints and tell him what its made out of. Says he will do it REAL cheap. This could cut down on my cost by a lot imo There is a guy on rx7club that built his own 4 rotor motor out of parts he had lying around and machining the rest. I believe he used 13b parts (and I agree with Smokey, there is no real reason you shouldn't use them also) but if you can find the thread you may be able to pm him and possibly get the specs he used. Quote Link to comment Share on other sites More sharing options...
carl1647545492 Posted January 21, 2015 Report Share Posted January 21, 2015 There is a guy on rx7club that built his own 4 rotor motor out of parts he had lying around and machining the rest. I believe he used 13b parts (and I agree with Smokey, there is no real reason you shouldn't use them also) but if you can find the thread you may be able to pm him and possibly get the specs he used. This guy has the right idea. Rx7 store did a 3 rotor conversion/install for 20K back in the day and they lost money on it. I say go for it (and let me know when you wanna sell it ) Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 22, 2015 Author Report Share Posted January 22, 2015 (edited) I like the idea of toying with the Renesis some more. In a book I have detailing the old 13b REW it talks about modifying the side housing which I guess if you know what you're doing should be no problem. However... I have no machining background and would love the opportunity to learn how to do this myself or practice on a few housings. I understand what you mean by moving a step forward and backward with the Renesis because Mazda had to meet emissions and other things so they had to tweak the engine before production. It is honestly hard to get information on the Renesis because no documents or books can be found detailing its specs and limitations, but if you know of any I would love to read and learn. I know for a fact that if you contact Mazda and ask them they have the capability to manufacture a 26b center plate (HYPER EXPENSIVE!). They have done it for several racing teams in the past and I believe with the right line of contact they would make one for anyone for a price. I am not ignorant to the idea of using the 13b housing from an RX-7, I understand the amount of work that goes into modifying the Renesis (which is a good point Smoky). I think I need to get some test housings and play around with them. Only so much I can learn from books unfortunately. @beatercamaro I would be very grateful if you could get that information for me. Maybe I could get in contact with him and see what he knows? Edited January 22, 2015 by ShowHBK Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 22, 2015 Author Report Share Posted January 22, 2015 (edited) @Carl... Where do you work at Polaris? I am at the McGraw Hill Building for a few more weeks. I understand that this is a crazy expensive project that is going to take a normal guy like me a long time to complete. Believe me though, I am VERY committed to doing this and seeing it through. Should I start with a 20b first before jumping to a 26b? know of any place that is local that I can practice or get some work shop experience? I wanna learn more about the more "hands on" side of this project. Hell, I would be fine with tearing the Renesis out of my own RX-8 if it got me the opportunity to learn. Edited January 22, 2015 by ShowHBK Quote Link to comment Share on other sites More sharing options...
B3NN3TT Posted January 22, 2015 Report Share Posted January 22, 2015 "Renesis" Not to be pedantic. Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 22, 2015 Author Report Share Posted January 22, 2015 "Renesis" Not to be pedantic. well...not my proudest moment =/ Corrected on all posts. Quote Link to comment Share on other sites More sharing options...
Green Bastard Posted January 22, 2015 Report Share Posted January 22, 2015 I cannot find the exact thread I was looking at a couple years ago about the 4 rotor build, but this thread may be of some help. http://www.rx7club.com/old-school-other-rotary-63/tegheim-home-made-4-rotor-wolvo-project-892879/ Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 22, 2015 Author Report Share Posted January 22, 2015 TYSM Ryan... Very interesting thread. For those out there with more machining and manufacturing experience and skills I have two main questions. 1. When looking for parts to get this thing off the ground, can I just buy used housings off Ebay or RX8 club? what are things I should look for in images before buying? Risks from buying used housings or rotors? should I just buy brand new direct from Mazda? 2. is there a place out there that I could disassemble or work on a 13b to get some experience? if not... is there a shop out there that would let me learn a little bit by getting some hands on experience? Videos and Books only get me so far =( I also found this thread...which has proved useful. http://www.rx7club.com/build-threads-294/4-rotor-fc-build-974831/page2/ I had a very deep CAD background, but I have no idea how or where these guys are getting their measurements to create the E-shaft. I would love to know where so I could take a crack at it. Quote Link to comment Share on other sites More sharing options...
Green Bastard Posted January 22, 2015 Report Share Posted January 22, 2015 I see no issue with used parts that you can get cheap for practice, or used parts that are in decent shape for a "first version" build (just to get one running then buy new quality parts to do the same thing so you know it lasts). Anything you buy online I would look for good prices on because it is easier for things to be misrepresented. Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 22, 2015 Author Report Share Posted January 22, 2015 I see no issue with used parts that you can get cheap for practice, or used parts that are in decent shape for a "first version" build (just to get one running then buy new quality parts to do the same thing so you know it lasts). Anything you buy online I would look for good prices on because it is easier for things to be misrepresented. Ya, It looks like I can get some 13b housing off eBay for about $200 and a few rotors seem to be around $50 a pop... I wonder i can just find someone with a surplus of parts... I would pay $200 all day for a non working engine if I could just play around with it... any ideas on where I could pick up one of those? Craigs list and Ebay are empty from what see. Quote Link to comment Share on other sites More sharing options...
Green Bastard Posted January 22, 2015 Report Share Posted January 22, 2015 Your best bet is to find someone who wants to swap their 7 and have no idea what they have. You should be able to pick up the keg pretty cheap. If I still had my old rotor housings lying around I would have given them to you, but they are gone. The other option is to buy an entire car (think fc) that does not run on the cheap and part out what you don't need (essentially getting the motor for free if you do it right). Quote Link to comment Share on other sites More sharing options...
Second Gen Posted January 23, 2015 Report Share Posted January 23, 2015 (edited) Mike, I would serioulsy reach out to one of the local RX7 shops. The "E" shaft and the cooling are critical in a three and even more so in a quad rotor configuration. Plus that monster would be loooooong. Make sure you don't have to extend the front of the car to get it to fit (Or sit in the back seat). The RX8 has a shorter snout than the RX7. Local shops Defined Auto works (Logan Carswell) Zavier (Was RX7 Store now.......) Carswell Rotary (Logan's dad) Others?? Not saying it isn't possible, but it will be stinking expensive.. 30 K for a three rotor sounded more of the norm and using a Cosmo 3 rotor. Plus the decision about turbo / not has to be made before you build the motor (High compression or lower compression dorito's / Rotors). Edited January 23, 2015 by Second Gen Spelling Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 23, 2015 Author Report Share Posted January 23, 2015 Mike, I would seriously reach out to one of the local RX7 shops. The "E" shaft and the cooling are critical in a three and even more so in a quad rotor configuration. Plus that monster would be loooooong. Make sure you don't have to extend the front of the car to get it to fit (Or sit in the back seat). The RX8 has a shorter snout than the RX7. It is a very good point. I know the E-Shaft is going to be a very important part to consider. Any idea on what material would be the strongest/best? Metal? Aluminum? steel? I know the front nose of the RX-8 is able to accommodate a 26b because I do know of someone on the RX7 forums that was able to do it. This image is more or less what I am going for. http://www.rx7club.com/attachments/rotary-car-performance-77/287656d1206003977-one-method-improving-rx-8-power-dsc06654-medium-.jpg Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 26, 2015 Author Report Share Posted January 26, 2015 Just got a book in today and I will be posting any interesting findings I find within it. Should be a good read. For anyone out there interested in this sort of thing I would 100% recommend buying or taking a look http://www.amazon.com/Street-Rotary-HP1549-Horsepower-Reliability/dp/1557885494/ref=sr_1_3?ie=UTF8&qid=1422254692&sr=8-3&keywords=rotary+engine Quote Link to comment Share on other sites More sharing options...
Yasser-Hanbali Posted January 26, 2015 Report Share Posted January 26, 2015 when it comes to 3-4 rotors, you would want to run the non rx8 housings and irons, also the E-shaft is not something you want to go "cheap" on as suggested i think you should highly consider visiting defined and talking to Logan as he has actually built a 4 rotor. he knows the right steps and the cost estimate that it will run to make one. for example a proper 20B build and install with all the supporting mods is anywhere from 15-25K Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 28, 2015 Author Report Share Posted January 28, 2015 Something that I came across in my research and planning it that I have decided to switch away from Renesis housing because of one BIG problem with P-porting them. The problem is that the exhaust ports on the side of a Renesis are already maxed out and can barely be opening up anymore without breaking through to the cooling area around the housing. I believe it could be done with some tweaking, but not worth it in the long run because according to some numbers that I ran last night it would weaken the housing WAY to much to run it hard or for a long period of time. Would anyone happen to have a way for me to get in direct contact with Logan? I keep hearing his name over and over and would be very interested to learn from him and his team. I really want to have an opportunity to work on an engine or play with some of the bits before doing anything and he sounds like the guy to talk to. Could I get his contact info? or is it worth calling Defined directly? It really does make me sad though, because I believe the Renesis could produce some crazy performance if made into a 26b. But so many things would have to be changed from a 13b REW housing 26b to make it work. I am not even to the part where tuning and timing come into play. Blah... I will update as soon as I find out more. Quote Link to comment Share on other sites More sharing options...
ShowHBK Posted January 28, 2015 Author Report Share Posted January 28, 2015 for example a proper 20B build and install with all the supporting mods is anywhere from 15-25K This is by no means something that will happen overnight for me. I am well aware that this is going to take me a few years or so to complete at the rate I am going, But it is going to be so satisfying to complete. I am 110% committed to doing this and seeing it through to the end. Quote Link to comment Share on other sites More sharing options...
carl1647545492 Posted January 28, 2015 Report Share Posted January 28, 2015 @Carl... Where do you work at Polaris? I am at the McGraw Hill Building for a few more weeks. I understand that this is a crazy expensive project that is going to take a normal guy like me a long time to complete. Believe me though, I am VERY committed to doing this and seeing it through. Should I start with a 20b first before jumping to a 26b? know of any place that is local that I can practice or get some work shop experience? I wanna learn more about the more "hands on" side of this project. Hell, I would be fine with tearing the Renesis out of my own RX-8 if it got me the opportunity to learn. I freelance for a magazine that's based out of state. I think your best bet is with Logan...this is what he does...dibs on ride when you finish. Quote Link to comment Share on other sites More sharing options...
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