2ND generation rx-7 --- v-8 conversion kit.

[Chris V]

Originally posted by Kaneto


To some people, a car almost is a religious shrine.

People love different cars for different reason, and it's not always something that you can just boil down to numbers. Heritage and history have a lot to do with it.

If you make a mass produced compromise of a car a religious shrine, you have a problem. And if you start denigrating people who are building personalized versions of that car to better fit THEIR desires, then you have a SERIOUS problem, and need to step back.

Yes, you can put a V8 in a RX-7 and make more power than most rotaries out there. Sure, you can make it handle about the same. If that's the way you want to go, then by all means go for it.

You can make it handle better. My car, with no other suspension mods, handled better after the conversion than before. Do you understand that? That isn't "about the same." I've been autocrossing for a couple decades, and was an SCCA and BSCC driving instructor. I've driven everything from huge sedans to formula cars on the track, and built national championship winning autocross cars. I know what handling is about.

Understand, though, that to a rotary "purist", the rotary is part of the car. Taking the rotary out of the RX-7 is like taking someone's heart out. It can be replaced with something else... but to some people, it's just not the same.

No, to a rotary purist, the rotary is theonly part of the car that matters: without it, the car is crap. They completely ignore every other good quality of the car. It is not a complete package. It is a home for the rotary, and the rotary, to them, is what imbues the rest of the car with goodness, as though the ONLY reason it works the way it does in every other area is that engine. This is demonstrably untrue! The rotary is ONE internal combustion engine design. It's a fabulous design. But it's only one part of the whole car.

It's not ignorance, it's love. Love for the car as it was built, and the history that the line has. If you refuse to accept that some people can hold such reverance for a car's design, then it is you who is ignorant.

I don't refuse to accept it. I refuse to allow those narowminded fools to denigrate people who are NOT narrowminded, who are NOT mentally challenged by being religiously blinded by a goddamn bit of mass produced, manmade mechanical invention!

Telling people that they have irrational "love" for a mechanical device is not being ignorant. What is ignorant is the statements of "fact" they make about the cars in stock and modified form, most of which are demonstrably untrue. Spouting non-facts to a quasi-religious bent is ignorant.

(edit- dang tags...)

[Kaneto]

Originally posted by Chris V
If you make a mass produced compromise of a car a religious shrine, you have a problem. And if you start denigrating people who are building personalized versions of that car to better fit THEIR desires, then you have a SERIOUS problem, and need to step back.

It's called a figure of speech.

And in no way am I denigrating anyone else's decisions on what they do to their cars.

You can make it handle better. My car, with no other suspension mods, handled better after the conversion than before. Do you understand that? That isn't "about the same." I've been autocrossing for a couple decades, and was an SCCA and BSCC driving instructor. I've driven everything from huge sedans to formula cars on the track, and built national championship winning autocross cars. I know what handling is about.

You'll have to explain how a car with roughly the same weight distribution, as you've pointed out, and no changes to the suspension, handles better. Are you sure it isn't in your head?

No, to a rotary purist, the rotary is theonly part of the car that matters: without it, the car is crap. They completely ignore every other good quality of the car. It is not a complete package. It is a home for the rotary, and the rotary, to them, is what imbues the rest of the car with goodness, as though the ONLY reason it works the way it does in every other area is that engine. This is demonstrably untrue! The rotary is ONE internal combustion engine design. It's a fabulous design. But it's only one part of the whole car.

Then I don't know what rotary purist you've been talking to. For myself, and every other rotary fan I know, it's about the total car package. It's about the car as a whole, and the rotary is part of that car. I doubt your "rotary purists" would be so adamant about a rotary engine in a Mustang. Sure, it would be a neat conversion, but they would still recognize the fact that the Mustang wasn't built with a rotary in mind, just as an RX-7 wasn't built with a piston engine in mind.

I don't refuse to accept it. I refuse to allow those narowminded fools to denigrate people who are NOT narrowminded, who are NOT mentally challenged by being religiously blinded by a goddamn bit of mass produced, manmade mechanical invention!

Telling people that they have irrational "love" for a mechanical device is not being ignorant. What is ignorant is the statements of "fact" they make about the cars in stock and modified form, most of which are demonstrably untrue. Spouting non-facts to a quasi-religious bent is ignorant.

Well then good for you. Just understand that not all "rotary purists" are like the ones you've talked to. Just because I would never put anything but a rotary engine in a RX-7, doesn't mean I think a 7 with a piston engine will be any less of a car performance-wise.

[Steel]

Can't find the source, but Yamamoto himself said (paraphrasing) "Without the rotary, the RX-7 cannot exist..."

edit: here it is! "Almost immediately after taking over the RX-7 program, Kobayakawa began work on the next generation. And while there was total freedom over the powerplant choice for the new sports car, the rotary was selected, first for compactness and power potential, but also for heritage. Said Yamamoto: "To forsake the rotary would be losing our identity. The RX-7 could not and would not exist without the rotary"

-Very Good RX-7 page

[Chris V]

Originally posted by Kaneto


Well then good for you. Just understand that not all "rotary purists" are like the ones you've talked to. Just because I would never put anything but a rotary engine in a RX-7, doesn't mean I think a 7 with a piston engine will be any less of a car performance-wise.

I built the car in '93. Since then, teh vast majority of people who have seen it have ben understanding, including on RX7 mailing lists and message boards. But ALL of the rotary "purists" that have chimed in have said very nearly verbatim (including some of them right here in this thread) what I described. Trust me, after hearing the same thing from a small group of people (all of whom claimed to be rotary purists), for nearly a decade, you get the idea that they really are all the same. Everyone who liked the car made sure to state that they weren't rotary purists, and everyone who spouted the misinformation and the claims I stated made sure to announce it.

Originally posted by Kaneto
You'll have to explain how a car with roughly the same weight distribution, as you've pointed out, and no changes to the suspension, handles better. Are you sure it isn't in your head?

Did I not state that clearly enough? I autocrossed the car before the conversion for a year and after the conversion. I got to drive it extensively in both forms: as a rotary engine autocrosser and a V8 autocrosser. In V8 form it was more stable and turned in better. It was easier to balance on the throttle and wasn't as twitchy (which I really wan't expecting...). The weigh was approximately the same, but it went from 51/49 to 49/51. When going for that last few hundredths of a second, that's a noticeable difference. Especially to someone trained to notice such differences.

[Kaneto]

Originally posted by Chris V


Did I not state that clearly enough? I autocrossed the car before the conversion for a year and after the conversion. I got to drive it extensively in both forms: as a rotary engine autocrosser and a V8 autocrosser. In V8 form it was more stable and turned in better. It was easier to balance on the throttle and wasn't as twitchy (which I really wan't expecting...). The weigh was approximately the same, but it went from 51/49 to 49/51. When going for that last few hundredths of a second, that's a noticeable difference. Especially to someone trained to notice such differences.

No, you didn't. But thank you for clarifying. Moving 2% of the wieght from front to back really isn't that difficult, regardless of what engine you have in there.

Basically it tells me than a V8 conversion can be made to handle better than a stock RX-7 similar to how a few simple mods in a rotary-powered RX-7 can be made to handle better than stock. All that seperates then is personal preference in the power delivery.

[Big Guy]

what about that new renesis motor? if there is going to be a 3 rotor version () to compete with the v8 sb im pretty sure it would beat the crap out it.

my $.02

[Chris V]

I really hope for good things from the Renesis. But, like the 20BTT, it isn't a cost effective swap compared to the V8 in a car like the 2nd gen RX7 (though it would be a much better choice than the 20B for handling). All I really hope is that the Renesis engine will start a resurgance of rotary engine interest in new cars and race cars.

.................................................. .........

Basically it tells me than a V8 conversion can be made to handle better than a stock RX-7 similar to how a few simple mods in a rotary-powered RX-7 can be made to handle better than stock. All that seperates then is personal preference in the power delivery.

Which is what I try to impart to people that say the car has had it's balance ruined. The car is balanced better than a stock RX7, and weighs less than a stock RX7 turbo. Even though you can improve both the stocker and the turbo, no one calls them poorly balanced or overweight, so any version that is improved over the stockers cant be called bad, regardless of how the power is delivered.

And yes, personal preference is the key. I love rotaries, but my wallet wouldn't let me have a 300+ hp one. Heck, at the time, it didn't want me to spend more on a stock rebuild.

[Steel]

well, IMO, V8 7's don't bug me. Not my cup of tea, but i think it's cool if people want to do it. The guys at rx7club are are anal-retentive. Uh that's about it.

*edit* actually, i think it'd be really cool if someone put a FERRARI V8 in their 7. Somehow. That would just kick major ass.

[Chris V]

So true, Steel.

BTW, looking at your sig for coming mods:

"Remanufactured street ported TII S5 engine, TII Tranny and drivetrain, GReddy T04E Turbocharger, GReddy 24v FMIC, Haltech E6K EMS, 760cc/1600cc injectors, Corksport single/dual (still deciding)catback, Electric fan"

What's the cost, and what's the power output (both hp AND torque)? How about daily driver reliability and docil street manners when off the throttle? These are the reasons that I couldn't budget to build a turbo rotary for my car when it died. As I recall, just the Haltech E6k is around $1200, and that doesn't include the specialized MAP sensor, O2 sensor, connectors, or terminated wiring harness. I did my conversion to 390 hp and 400 lb ft of torque for under $2000 total (not including purchase price of the car itself, which was a trade for a car I got for free...).

A lot of people say they can get 400 hp from a rotary. But the cost is enormous in comparison. If they wanted me to go that way, THEY should have had to come up with the difference in cost. I have nothing against building a fast rotary. I just want to stress this isn't a bad way to go, either.

[Cbass]

400hp with a ported TII engine isn't hard at all... then again, there's no need to buy outlandishly expensive GReddy stuff. A rebuilt T04 will provide all the air you need, and with stand alone engine management, you don't need an extra fuel, ignition or boost controller.

Rotaries aren't all that expensive, as was shown earlier in the thread in a link that I think Kaneto gave me... $2400 for a professionally ported and rebuilt TII, which is quite reasonable if you look into buying a crate engine. That's comparable with a 330hp Vortec 350 for $2500, and the RE has more potential on it's stock internals.

Still, $2500 is completely out of my league right now, so I'm going to stick with the 400M/G31 concept.

[Steel]

eh, check the sig again. I'd rather waste the money on a FD now, because that 2nd gen wont be very streetable.

[Chris V]

Originally posted by Cbass
400hp with a ported TII engine isn't hard at all... then again, there's no need to buy outlandishly expensive GReddy stuff. A rebuilt T04 will provide all the air you need, and with stand alone engine management, you don't need an extra fuel, ignition or boost controller.

That stand alone engine management runs close to $2k all by itself.

Rotaries aren't all that expensive, as was shown earlier in the thread in a link that I think Kaneto gave me... $2400 for a professionally ported and rebuilt TII, which is quite reasonable if you look into buying a crate engine. That's comparable with a 330hp Vortec 350 for $2500, and the RE has more potential on it's stock internals.

Add to that $2400 of the rebuilt TII (which did not exist back in '93, sorry.) the cost of the previously mentioned engine management, and the rebuilt larger turbo, and you can see the costs spike pretty quick, and teh end result is a ported rotary with a turbo, which makes great uppper rpm power numbers, but becomes not very driveable in daily use and has a vastly reduced lifespan.

I've seen these rotary cars and how long they last between rebuilds at these relatively low hp numbers. To me, they are very simple to rebuild, but the benefits don't outweigh the drawbacks.

The Vortec SBC can withstand greater amounts of detonation if it happens (read it can withstand any detonation, which the rotary can't), and overal potential is greater from the smallblock. The rotary is a turbo already at that power level, while the SBC can still be turbocharged or supercharged for serious power with similar reliability and driveability to the lower power turbo rotary. Most guys, however, are buying good used V8s from late model Camaros and Firebirds, and getting the engine management and 6 speed transmissions with them for that price, and not dealing with the lower potential of the Vortech engine.

Of course, in both cases, you've left budget way behind, so to me, it becomes immaterial what its ultimate potential is, as I'm never going to spend that much on an engine.

[SlipoftheCondom]

Anyone know of anyone running a LS6 in a 7? I have a Turbo II (no engine/transmission) and a machine shop next-door with a LS6 that may be for sale... I've found kits for the LS1, but not the LS6... Can anyone help me out in pointing me to the right direction?

Please, no need for "Don't do that to your RX7" comments.

[Steel]

Well now, im thinking of going piston power.

NO! not what you think! my 7 is keeping its spinners.

Nope, what i meant is that toyota supra's have caught my eye. Only problem is that mk4 supras are ridiculously overpriced. But i might get lucky.

[FunkLord]

theres some pretty pathetic and ignorant responses here.... a v8 has its advantages... so does a rotary... the worlds fastest rx-7's are all rotary powered. a 20B engine has the potential for 4-digit HP on the stock engine block. a v8 will have more low end torque, and in the 450-500hp range, will be more streetable. but when you get up to the higher hp ranges, both of them throw streetability out the window... probbably a supercharged v8 would have the best streetability with the highest HP... but superchargers arent cheap. even if you make a v8 rx-7 as light as a stock t2... you can still make the rotary rx-7 lighter. the block itself it lighter. any weight reduction can be done to both versions. even at the same weight, the rotary one will have a lower center of gravity because of how the engine sits... a n/a v8 wont be able to make as much power as a turbo 20b. but a turbo v8 would be able to... but again... turbocharging a v8 isnt cheap or easy. and in terms of gas mileage and reliability... i ask you this: would you swap a 1.6L honda engine into your car? probbably not.
theres plenty more to go into, but the fact remains that everything has its ups and downs. you have to evaluate your own goals and see what suits you best.

i drive a rotary powered rx-7. heres my reasons
-handling
-its different... most people dont even know what it is let alone how it works
-power:weight
-rotary's love turbos, and so do i.
-in my opinion, a rotary engine has a superior design, it just lacks the overwhelming R&D that piston engines have and that one day all cars will be rotary powered...it almost happened once already! as long as the internal combustion engine doesnt become obselete first...