How is it you have a copy of the Renesis crate-engine warranty? It's not been completely set in stone yet.

 

look at any of the current parts warranties, if you can get something else thats cool, but unless you get a different warranty than everyone else you wont get one

mike

 

A crated engine is understood to be put into a variety of cars, whereas other parts are usually warrantied to be car-specific.

 

ive worked for mazda for a long time, you need to make sure they understand that. btw it would be really cool if they would do that

mike

 

--matt

 

Not accusing your comments were originally directed at someone else so I was asking if you'd read my post.

'Far as I know the ECUs are stock RX-8 ones.

We need to understand something about the automotive industry: (caution: lecture mode. Those already in the know, please skip ahead)

Like the aircraft industry, the automotive world designs a range of vehicles with similar basic stampings and parts (known as 'platforms', the interchangeable K-cars of 80's Chryslers being the most notorious example, though the rebadged 'brand engineered' GM cars of the same period were a far greater insult to consumer intelligence - but I digress).

They mate these platforms with a variety of separately engineered power packs (engine/tranny combos) which is why you often read things in Car and Driver like 'Ford is offering this SUV iwith V6 or V8, both mated to the crappy DB1423 automatic transmission used in the Ford POS for the past 10 years'. (remember, I said 'like' - bolt counters will be quick to point out there is no DB1423 tranny - or maybe there is and I just popped my secret-agent memory cap)

In other words, you've the platforms (think Chassis), then the power packs (engine/tranny) and they plug what is the best/most cost effective/most marketable (one of the three) power packs into a platform.

What Mazda has done is engineer an all-new engine (yes I know it's sort of, kind of like the 13B, but the latest 4 boinger from Honda is sort of, kind of like the old CVCC engines while being all new).

New engines are such a huge undertaking that GM and Ford are actually collaborating on a new engine product, rather than independantly duplicating each other's efforts. Sort of like throwing a party where the English provide catering and the Italians provide security, but again I digress.

So Mazda has an all-new engine going into an all-new platform. For such a cash poor company this is a collosal undertaking, and the fact that they've been delaying things to get 'em right is okay in my books. This does, however, mean that there is a bit of disorganization. Unassigned part numbers, deal-by-deal 'programs' for volume order buyers like myself, etc.

I'm aware that Mazda is leaving themselves wiggle room on both pricing and fulfillment, which is why for the past half year I've more or less kept my mouth shut about these negotiations. Until the engines are in my warehouse with a bill of sale, I don't have any to offer buyers so discussing it would be like a person with no racing or tuning experience discussing their plans to build a custom engine for record-setting performance. Nice info, but even I don't know where it well lead - yet.

 

My point, well put... Mazda will try to make as much as possible transfer from current cars (the RX-7 still in production), so my guess is they wont want to deal with certain changes (ie. tranny-to-engine bolt locations) I'm guessing if we could compare the current RX-7's powertrain equipment with the RX-8's we'd see some similarities....

And something that I'd like to discuss is the actual dimension changes .... Some have been quite adament that the new renesis is quite different from the previous 13B, and in many ways they are probably correct. For one, it is easy to notice that both new rotor housings and side-housings will be on the new engine. Still I doubt the size of the rotors and housings major dimensions will have changed. Some possible rebuttles for this is that the rennesis is claimed to have a higher compression. As the same time, people think it looks smaller. This doesn't jive with me, because the main thing that controls the compression ratio, is the ratio of eccentricy to the housings major axis. I recently read a history of the development of the rotary. Wankel noticed that the less eccentric the shaft was, and subsequently the tighter fit of the rotor in the housing (by this I mean the smaller the overall chambers), the higher compression. So to keep an equal displacement, the entire housing and rotors have to become larger, the overall shape of the housings less oval and more round, and the rotors the same. (He showed some extremes, one one hand with nearly triangle rotors -CR like 5:1- and rotors that nearly were round - CR like 30:1- that was about 3x the area (and therefore mass) of the triangle rotor type. Just looking at the pictures of the renesis, I don't see any of the major changes necessary to dramatically change the compression ratio. Small ones could take place, but the fact that the displacement is 1.3L and that the rotors are lighter (doubtfully larger and lighter), I consider it highly likely that the overall shape of the engine is unaltered. The dishes in the rotors on the other hand can control minor changes in CR, so I expect these to be further decreased in size/depth, so increasing CR.

From this conclusion, its easy to speculate that there will be swappable parts.... ie renesis with lower compression 3rd gen rotors, swapable front-covers, oil pump, etc. That would/could make this engine quickly accepted by the aftermarket, and that would make this swap not only possible, but very feasible and likely.

Of course the ability to swap may easily be thwarted by minor changes... so we will just have to wait and see

 

I'd just like to add this: If no one buys the RX-8 and just swaps crate engines into the RX-7, the RX-8 will have a hard time surviving. Its the rotary enthusiasts, that ultimatly have to promote the car by purchasing them to keep the rotary alive. Their becoming popular will require a good number of them driving around to advertise.... so if at all possible consider buying one.... I know I want to, when I finally get out of school

 

The RX-7 is no longer in production for any market, Japanese or otherwise. The last one rolled off the assembly lines in mid 2002.

probably looks smaller because, with side exhaust ports and no turbo, you don't have the huge cluster of vacuum hoses.


Not neccessarily. You can have two different piston engines with the same bore and stroke, yet zero part compatability. The Renesis uses different seals, different rotors, different housings, different intake, different exhaust - that doesn't leave much.

True, but the market for new and used cars are different (Chevy sells a ton of V8s without cannibalising the market for Corvettes). Some are content to go through the time and expense of buying an engine and instanlling it in an older vehicle, whereas others want the latest piece of machinery out of the box parked in their driveway.

Just because enthusiasts such as we are willing to work on our cars, we should not forget that the majority of people prefer to buy a vehicle they just drive, take to the dealer for regular servicing, then dispose of for the Next New Thing every few years.

 

ehhh 6 on one hand 1/2 a dozen on the other

 

Speculation is speculation, true, but It stands to reason that if its the same size, It could fit. Remember the new(86+) and old (85-) 13Bs pretty much fit the same discription: different seals, different rotors, different housins, different intake.... ok the exhaust was pretty much the same. See my point. Some changes are inevitable... will they make reversablity impossible, no one knows.

 

Rotaries, and V8s both exist on earth, but thats about where similarities end. The V8 never has, and probably never will (as far as internal combustion engines are conscerned) be in jeapordy of being forced out of the auto market. Lets face it, the rotary is faced with extiction. If Mazda flops yet another rotary model, how many more times do you think they will try? How long after they give up, will OEM parts manufacturers also throw in the towel? Mazda is sticking their butts out on the line on this one.... we don't want them to run off sheepishly.

 

You missed my point (or maybe I was fuzzy about what my point was ). The number of RX-7 owners who have the time/money/patience to put a Renesis engine into their existing chassis aren't likely to be of significant quantity to greatly and measurably diminish the number of RX-8s sold.

Your point about the demise of the rotary should the RX-8 fail is well taken; indeed Mazda has hinted at the same thing themselves. However you seemed to be saying that buying just the engines would vastly shrink the RX-8 market, to which I countered crated angines and new cars arer two separate markets with little, if any, overlap.

 

Um, I hate to be a bear, but you guys who keep saying the Renesis should fit and that its the same cross section are way out of line. First off, you need to go to Mazda's site and READ about it.

They claim to have reduced the engine block size by 20%.

They also state that the engine is now smaller than the cross section of the tranny.

A major difference is that you no longer have ports on the trochiodial chambers.

Therefore, no hole, no stress amplifier to deal with through extra material compensation. The housings will now distribute the load much more evenly and thus, a thinner amount of material is needed. This is the first thing I notices, looking at the cross section.

There are also pics on Mazdas site of the engine bay. No offense, but it as dis-similar from the 3rd gen as it is from mine. Maybe alts, smog pumps and what not the same, but that's it.

And once again, making a front brace will be considerably cheaper and will not void your warranty like removing the front of the engine will.

 

So, it'll be the size of a 12A again!!

 

uh... not likely. They didn't decrease displacement, but total engine block volume

 

20% smaller..... Ok, when I'm wrong, I'm wrong.... that thing is going to be much harder to in swap then. $5 to the first to do it (OK, so I'm poor.... back off!!)

When it comes to engine bays, I expect alot of changes... IMO, that was the leading cause of reliablity problems, because it doesn't breath very well. But first gens are much better endowed in this catagory, and they have alot more room to play with. This won't be the issue, it'll be mounting, wiring and tuning.

 

I'll hold you to that.

 

Man I have read all the post that when up since my last on this thread and allot of people keep on thinking that there going to be able to buy these motors for peanuts from the junk yards... I got a idea go out and see how much it is for a motor out of a new car which is COMPLEATLY REDESINED for this year... complete with wiring harness ECU throttle body fuel rail etc… THEY ARE WORTH THERE WIEGHT IN GOLD... there going to want ONE HELL OF ALOT MORE THEN 3-4k for them... it IS cheaper to go out and build a turbo motor... mantis made me aware of something I wasn't aware of in this thread about the rotors being hollow... this means that the motor isn’t going to have the ability to make the power the 13b's make now for SOME TIME TO COME... new cars are expensive to mod and that goes the same for the motors... even if a new motor design shows much potential they are STILL going to be extremely expensive to build for some time to come and wont come to its full build potential for WELL OVER 5 years after it starts being produced... as far as the warranty on crate motors go I don’t know why they would warranty a Renisses motor right away because the vast majority of these motors they will sell are going to people with the express purpose of beating the **** out of them... if they DO offer a warranty it would prolly be voided by stupid little stuff such as after market fuel and ignition controllers, headers etc...or at least it would probably be in there best interest to...

 

Make sure its a nicely built 400hp turbo 2.3 or youll be fucked!!!!

 

You can make ONE HELL of alot more power out of a 13b then you can out of a 2.3

 

I read in car and driver that Mazda Doesn't ever plan to have a turbo option. WTF? If it has 250 HP N/A, I wonder what 20-30 pounds of boost would do for it. I think it's stupid that Mazda isn't really pursuing the Rx-8 has a high performance model. But that's my 2 cent.

 

Turbo does NOT automatically equal high performance. There were turbo 3 cylinder Geo Metros, remember? Turbo is a way of increasing engine output until the manufacturer can come out with a redesigned engine. The Renesis puts out as muck stock horsepower as the FD's 13B which neede TWO turbos to do so, and some of oyu are coming across like Mazda is making detuned, wheezy engine.

250 HP right out of the box without all the plumbing or extra parts of a turbo system - how is that a bad thing?

 

Detonate and blow it up?

 

I just meant, that it better be built right, rather than some ******** just turning up boost so they have 300hp when the turbo kicks in. If its built right it could be reliable...but yeah, ROTARY POWA!!!

Swapping a 2.3 in a RX is the worse thing you can ever do. Yes, including murder.