13B-REW (mazda rx-7 engine), in a 1st gen. 240sx

[sacrifise8]

well, this is a swap I've been pondering on in my mind for a bit now, and I wanted to know how difficult it would be. I know I would have to get custom engine mounts, and things of that nature. I'd just like to know, how hard would it be? The reason I'm asking, is because I've found a place that sells the 13B's for only $100 more than an SR20, which has 50hp less than the 13B.If anyone can help, please do so. -Julian.

[BigJuiceSr20]

There was a guy down here in Miami that had a built 13B in his S13 and that car was wicked! He blew the motor and installed an RB. He blew that as well.

For what you're gonna pay to fabricate the mounts for the 13B to fit and make custom drive shaft, etc, etc you're better off getting the SR or better yet just turbo the KA which will be much more economical.
Modified by BigJuiceSr20 at 2:30 PM 2/21/2008

[90_rb20]

^ Agreed with most of what he said.

Seeing that Ive onwed 2 FD's and a FC I have a bit of rotary knowledge.

Things to think about:

If you can weld, you can make your own homemade mounts cheap. If you cant, youre looking at about 1500 for a quality job.

Drive shaft will run you about 3-400 depending on your local shops pricing. You can call Clutch Products in Mobile, AL spend a tad over 300 for a GREAT piece.

Factory Rotary seals are not horribly strong. Usually swapped out with APEX. If you cant build a rotary you're going to spend about 2K for that. Usually while you're in the motor you port it (IE: Street, Race, Bridge)

Non sequential set up can be done with garage tools and a 6 pack. Parts are not terribly cheap, but there are alot of used parts floating around, like the SR20 parts market.

Have to run an aftermarket ECU to make respectable power. I personally used a Power FC w/ commander for all of my tuning.

Using high cc injectors for the ammount of power. I made 396 rwhp on 15lbs on pump gas and was using 1200cc and 800cc injectors.

Rotaries arent great for daily drivers, but make hell of a sound and great throttle response.

Seeing that I love rotaries I say go for it, SR's and Arbys are only "awesome" for so long.

Good luck mang

[apollas]

Mmmm 15mpg 13b - no boost, no mods

[IanS]

Slap some webber carbs on it, so you dont have to deal with wiring, and go have buckets of fun.

[Ls1pwr]

rotary's are garbage and very unreliable, a 1.3 liter rotary weights about the same as an 5.7 liter Ls1 but the Ls1 is reliable makes about 350rwhp and matching torque. if your going to do an engine swap at least do something thats reliable and wont be breaking down every 10-20,000 miles, build something that u can beat on day after day (ala Ls1)

[IanS]

rotary's are garbage and very unreliable, a 1.3 liter rotary weights about the same as an 5.7 liter Ls1 but the Ls1 is reliable makes about 350rwhp and matching torque. if your going to do an engine swap at least do something thats reliable and wont be breaking down every 10-20,000 miles, build something that u can beat on day after day (ala Ls1)

A well maintained rotory is actually very reliable, and they are very cheap and easy to maintain, an LS1 on the other hand, is going to cost you an arm and a leg just to get a hold of, and I for one have never been wowed by GMs reliability. Just because you cant wrap your mind around how a Wankel works, doesn't mean you should call it garbage.

[90_rb20]

A well maintained rotory is actually very reliable, and they are very cheap and easy to maintain, an LS1 on the other hand, is going to cost you an arm and a leg just to get a hold of, and I for one have never been wowed by GMs reliability. Just because you cant wrap your mind around how a Wankel works, doesn't mean you should call it garbage.

Outstanding

[grmreapr]

I would say go for it I love rotaries the only thing I would fear would be doing the wiring and you can make an insane amount of power with a 13b leave it to mazda do come up with something insane and actually make it work.

[My RB25]

Hey Sideways...get outta my head lol. Well said bout GM's (or any other American manufacturer for that matter) and rotaries

[Vegascorbin]

Sideways: Amen

Also just because a particular swap dosen't sound right to you is no reasion to bad mouth it. Now if someone has done a swap and found problems that need to be avoided or worked out that is what this forum is all about.

I am sure that the regulars here read something every day and go: ????Why did they do that?????

I would love to see a rotery engine come in a low price car again like it did in the 70's. Yes I was around then you young wippersanpers:)

[My RB25]

One day I'd like to tackle a rotary, I just heard you really gotta know what your doing with them. I can't remember what mag I saw it in, but they had a article about the rotary, gave a brief history on it and a tear down of the renesis motor (sorry don't know the engine code). As I said...one day, first I'd like to get a few regular motor builds under my belt

[IanS]

One day I'd like to tackle a rotary, I just heard you really gotta know what your doing with them.

This is true of any engine, you wouldnt dive into a total rebuild on a piston engine without any knowledge pertaining to them, the same is true for rotories, they are no better or worse, just different.

I would say go for it I love rotaries the only thing I would fear would be doing the wiring and you can make an insane amount of power with a 13b

Thats why I say go with carburetters, you avoid doing almost all the wiring, and you can make crazy power on the cheap, Ive seen 13bs with only a bridge port, a dual webber carb setup, and an upgraded ignition system make as much as 200 RWHP at 10,000 rpms. I personally hope to pick up a clean FC this year or next, I miss the sound of a pissed off chainsaw tearing down a freeway entrance ramp

[godzilla34]

i dono bout rotry in a 240.... but i am helping a friend swap his into a miata =) small car + wicked motor = ????? ooodles of fun!!!! id say go for it man, time is money tho, so take your time and do it right the first time and you wont have to waste any cash.