RX-7 hybrid

Kenetix said:
There's no point in even owning an RX-7 if you're going to throw anything other than another wankel in it.


Indeed..
I love the rotary but also other engines... I just like the rotary more than piston engines, if only for it's concept and technology
Especially the ones with serious power..
An RX7 with a V8 or anyother piston-engine isn't a RX7 anymore.

The rotary-engine loves to rev.
I agree with the lack of torque at low rpm, but that is what the rotary makes the rotary...Once it's on it's way, hold on!! Love it or leave it...
Besides, if one does some tuning for low-rev torque on a rotary, and you'll match any piston engine..
But don't forget that it's not fair to compare the 1.3l 2rotor wankel (turbo or not) to a 350cui V-8...
It really easy for a big engine to produce loads of torque...
A stock RX7 FD is comparable to 3.0L engined cars, like the a stock Toyota Supra twinturbo...
My opinion is that no piston engine can match the smoothness of a rotary.. (at least, not with aid of elerctronics, balancing-shafts etc. etc.
And as for the reliablity of the rotary : it's fine...
At Le Mans, the Mazda rotary had 67% of their cars finishing, next to 55% (D.B. - France) of the piston-engined-cars...
Only Honda had more finishing cars, but they only raced Le mans one time, with 3 cars, and all 3 finished...

Besides : The rotary engine has a totally different approach then a piston-engine...
Build a 350cui rotary and it will out-perform a V-8 of the same size!!
It easier to make a big engine make more power/torque than a small one...

And indeed, rotary engine parts might be more expensive, but then again, you don't see millions of rotary engines around, like you see the millions of V-8's that were produced.
But still : Rebuilding a V-8 can be just as expensive or even more costly than rebuilding a rotary-engine... Let alone tuning..
 
All else aside, you have to really be sure the engines powerband will even match the gearing/weight of the car. I have seen too many hacked up RX7's with 305's/350's that are setup to run around 5500 rpms- put that in a 2600-2800 lb car with 4.10's and dinky little tires and tell me how well that matchup is :). Yeah, they will spin the tires with ease, but after that, they don't go anywhere. You need a small block that is good to 8000 rpms (full roller motor) to even be close to right. Either that or you need to drop the gearing to around a 3.27 or so or try to put taller tires under it. I opt for the gearing- now not only are you doing the motor, but you need to setup a live axle rear in the car- you just destroyed everything this car was about :). It would be a cool project if done right, but for the most part- it is a hell of a lot more than just an engine transplant.

Joe

RX7-79 said:
Indeed..
I love the rotary but also other engines... I just like the rotary more than piston engines, if only for it's concept and technology
Especially the ones with serious power..
An RX7 with a V8 or anyother piston-engine isn't a RX7 anymore.

The rotary-engine loves to rev.
I agree with the lack of torque at low rpm, but that is what the rotary makes the rotary...Once it's on it's way, hold on!! Love it or leave it...
Besides, if one does some tuning for low-rev torque on a rotary, and you'll match any piston engine..
But don't forget that it's not fair to compare the 1.3l 2rotor wankel (turbo or not) to a 350cui V-8...
It really easy for a big engine to produce loads of torque...
A stock RX7 FD is comparable to 3.0L engined cars, like the a stock Toyota Supra twinturbo...
My opinion is that no piston engine can match the smoothness of a rotary.. (at least, not with aid of elerctronics, balancing-shafts etc. etc.
And as for the reliablity of the rotary : it's fine...
At Le Mans, the Mazda rotary had 67% of their cars finishing, next to 55% (D.B. - France) of the piston-engined-cars...
Only Honda had more finishing cars, but they only raced Le mans one time, with 3 cars, and all 3 finished...

Besides : The rotary engine has a totally different approach then a piston-engine...
Build a 350cui rotary and it will out-perform a V-8 of the same size!!
It easier to make a big engine make more power/torque than a small one...

And indeed, rotary engine parts might be more expensive, but then again, you don't see millions of rotary engines around, like you see the millions of V-8's that were produced.
But still : Rebuilding a V-8 can be just as expensive or even more costly than rebuilding a rotary-engine... Let alone tuning..
 
I am in the process of doing a 350 camaro swap into my '86 GXL right now and have done a lot of research and found that even with the steel block 350's you will be lighter than a Turbo II by about 150 lbs. But it has been said in here before that the torque gains are incredible and it is a cheap option to getting the 13B rebuilt. I have had my 13B rebuilt twice and I can't bring myself to do it again. But that is just me.
 
I've Done the swap. They actually sell kits now that does pretty much all the fabricating for you. It makes things VERY cut and dry.
 

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try a grand national engine

My brother has a second gen. with a stock gn motor doing low 11's , all we need to do is to change the rear end to get in to th low 10's , this is becuase of the gears are to high .
as soon we get the corvette rear end in their we have lots of gears to play with.
theirs not much you can do with a stock turbo two rear end..
ill have pic's soon .. check me out later

p.s. lots of fun , this is a every day diver and by the way this car is in the chicago area . watch out....
 
stop ruining these RX7s ..... thats great that you make nice quarter mile times, but do it in a car that was meant to have a piston engine... (notcool)
 
try gmhightechperformance.com

Familia323 said:
stop ruining these RX7s ..... thats great that you make nice quarter mile times, but do it in a car that was meant to have a piston engine... (notcool)




look for the seach engine and type cadilac , look at my freind new toy a new cts with a gn motor over 400 horse power
 
(scratch)... uhhh....

ok went there, and saw what you were saying. Thats cool...A CTS B as opposed to the CTS V.... allright... but umm.. I was saying that people should stop ruining RX7s by taking out the rotary and putting in piston engines.
 
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Dont get me wrong i still love my rotary

I still love to (drive) my 79 with a 13B , down drafft dollorto's , and mild street port .
i used to hate guy's that did engine swaps , but as we all know it happen's all the time , so i got over it .. any thing goes on the street.


check out my 82 corolla convrtable at showusyourcorolla.com
 
I am not saying that I am against engine swaps. I think you are looking at this too vaguely. I am saying that you are taking an ultimately limited car and diminishing it even further by taking out its Rotary engine and replacing it with a piston engine. Again let me reiterate that I am not against swapping engines. But on this particular car I am. The R in RX7 is in part because of the fact that it has a Rotary engine. The reason why this car is famous is because of its Rotary engine. When you swap it out for a piston engine, it is what some feel a type of sacrilegous act. My point is that if you want great performance from a piston engine buy a car meant to have a piston engine. Thats all I'm trying to say. but nevermind.........................
 
As a rotary owner, I'll tell you this. If I blow another motor, I'm swapping in a V8. Plain and simple. More torque, more horsepower, and if it's packaged correctly, less weight...

To all of the people arguing that it's "blasphemy"..... A car is a tool. I use mine to compete against other people, and if I can have the upper hand by throwing a V8 in my 85 RX-7, I'm going to.

Did you know that some people argue that a V8 RX-7 may actually handle BETTER than a rotary car? The theory is that the center of gravity is lower....

Dan
 
Lt. Dan said:
Did you know that some people argue that a V8 RX-7 may actually handle BETTER than a rotary car? The theory is that the center of gravity is lower....

Dan
and to answer your question yes. But just like you have a choice so do I, and I would refuse to put that "blasphemy" of an engine in any RX7 that I own.


(nana)
 
Im a fiebrudo for rotary

Thats right about having our own opinions of rotary vs piston , but ill never give up on my first gen or put a piston motor, but as for the second gen everything goes (dark) .

Ive also seen rotary's doing 6's in 1/4 mile , but their all way's a cheaper war to gt them in to the 12's or 11's thats why you see some boriquas putting them on starlets with ar pistons .


well my point is that you ever made it to the 10's in a rotary chances are that you spend a hole lot of money to get their ..
prop's goes to thouse guy's ..
 
To each his own I personally belive to stay true to the soul of the car stick with a rotary. I have nothing against piston swapped RX's just figured if you wanted a LS1 or Small block Chevy buy a Camaro, 302/347 or 351 buy a Mustang, 3.8 turbo buy a GNX, a 4G63 buy an Eclispe and even a 2.3 turbo buy an EXP as for the 2JzGTE's buy the Supra. Now I will give credit where credit is do and i have seen some very nice piston sawpped RX's. So thumbs up on the build to those guys, but it's not for me
 
To each his own I personally belive to stay true to the soul of the car stick with a rotary. I have nothing against piston swapped RX's just figured if you wanted a LS1 or Small block Chevy buy a Camaro, 302/347 or 351 buy a Mustang, 3.8 turbo buy a GNX, a 4G63 buy an Eclispe and even a 2.3 turbo buy an EXP as for the 2JzGTE's buy the Supra. Now I will give credit where credit is do and i have seen some very nice piston sawpped RX's. So thumbs up on the build to those guys, but it's not for me
not trying to continue a never ending war, but the RX7 is lighter than all of those cars, hence why putting these engines in the RX7 is desirable to some people.

BTW bump from the DEAD!
 
cool thread I have a relatable experience,

at my old job my 2 bosses were 240sx junkies. they are both good at modding cars and have a full shop in their barn with lifts, welders everything.

1 has a 240 hatch and put sr20det with every bolt on you can think of. He made over 350@the wheels but keeps the boost down for everyday driving as its stupid fast even at 300whp

the other guy removed the k24, cut the transmission tunnel and attempted the ls1 swap. it took ALOT more effort than was planned. as far as I know his car is still sitting in the drivewat waiting for the finishing touches.

I was making fun of him one day and he called over his friend that had completed the swap.

the 2 240s (1 all external mods you can think of, $1500 EMS hours of dyno tuning etc. the other, stock ls1) ran against each other all day long on the backroads by our house.

neither car was better by any means, both took off amazing and were side by side every run. Handling was basically the same (the ls1 is actually lighter than the stock k24).

both cars ran great.

both cars spent about the same amount of money.

both owners are happy as **** with their cars.

the point of all the yammering is that there is more than one way to have your cake and eat it too. the ls1 is one of the nicest engines you can buy for its price. I wouldnt say its blasphemy at all to put one in a rx7, especially if you want to race your car all day long and have stock reliability. The rx7 is a very light car and even at WOT the engine is not even working. Say hello to 250,000KMs of worry free 11 second daily driving. :) Just put in the chevy and she will run (and beat) ferraris and 911s all day with turn key reliability.
 
you dont even have to check the oil level every 1000kms lol

love wankels too im just saying there is more than 1 way to skin a cat.
 
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