No Offense

[rotary911porsche]

But can anybody tell me the Best engine there would be to drop in to a RX-7 that would fit into the bay, and what transmission would go with the engine as well as fit into the body of the RX-7, and what would i have to install as far as axles, driveshafts, etc. what kind of axle and driveshaft would i have to install ( i mean a specific kind)


First you need to define "best". Cheapest, easiest install, most torque, most horsepower etc.
The Buick Grand National V6 engine already mentioned makes serious power with a Turbo upgrade. Your car will be in the tens in the quarter. These engines and tranny's are harder to find and more expensive than a V8 but may be worth the time and cost.
Just about any small block domestic V8 will fit. Use the transmission that came with the V8 (make cetain it has overdrive). Use the front half of the V8 drive shaft and the back half of the Mazda shaft. It will need to welded and balanced by a competent shop. Granny's has ready made drive shafts if you would prefer. If your Mazda already has the limited slip, five lug rear end, it will handle almost anything you can throw at it. There are a few people at Torque Central who are needing to upgrade their rear ends and axles. Most of these cars are not daily drivers and are making serious power. They are also using drag slicks. A rear end upgrade is very doable.
Some people are even running the stock four lug rear ends and are not having any problems.
5.0 fords are cheap and easy but need a hole in the hood (cover with a scoop). Chevy 350's usually fit with no hole in the hood. They are more expensive than the Ford. Both of these swaps are easy and you will find lots of help. A Mopar swap is very rare and you will probably be on your own.
If you need to pass smog you will need an engine from the same year or newer. A good wiring diagram will help sort out the connections. the Mazda fuel pump will handle all but the most outrageous setups.
A highly tuned 13B with a big turbo and nitrous may still beat a V8. I have a friend with a daily driver (full interior, radio, A/C) '88 that runs low tens in the quarter. If you check the times most V8 powered cars are running you will find that few V8's can beat him. But, his engine is a little less reliable than the same power V8.
The Toyota engine would be very unique. It would probably be much more expensive than a domestic V8.
It's your car, you can do whatever you want.

[ldstang50]

i know a j motor will fit, with some twisting, the morons in super street did it. but ca18 will fit too.

[banditkiller]

ANY motor will fit with the right amount of money and time...its as simple as that

[Entreri33]

Here is a question you need to ask yourself. Why put a piston engine in a rotory car? the spirit of the car would be lost with a heavy a$$ed piston engine. The 20b is a 300hp (mildly tweaked) non turbo engine and 600hp turbo with some serious mods and still retain the reliability. even a light wieght LS1 V8 it woudl throw off the balance of the car. And if nothing else the 20b has "kits" of sorts that are already in production and the "bugs of the swap have been worked out.

Any Unique engine swap will require the mechaninc (probably you in this case) to be creative and most likely fabricat unique pieces to make it work. If you are not capible of doing this then this project you are dreaming is not going to happen.

[rotary911porsche]

Why put a piston engine in? It's your car. Do whatever you want.
The V8 does change the weight balance a little but it is very easy to get back to 50/50. The 20B would probably throw the weight off just as much. Have you priced a 20B? I did for my conversion and the total with wiring and engine management etc. was going to be over $8,000. A strong V8 is much cheaper.
There are several places to purchase a kit to adapt a Chevy or Ford small block. It really is a bolt in installation. If you choose to retain the fuel injection of the V8, the wiring will be the hardest part. But there are companies (Painless for one) that will mod your harness and label everything. It's not cheap ($300 to $400) but it is easy.
Changing to an automatic tranny makes the job even easier. Adapting the Mazda clutch master cylinder to work requires some creativity. But many conversions are stick.
Again, it's your car. You have to ask yourself; "Do I really care if someone else thinks I violated the soul of MY car?" If you do care, keep it rotary. If you don't than make the swap.
One note of caution. If you plan on racing SCCA an engine swap will change your category. It is a major mod and you will be racing against serious track only cars. But if the car is for fun it is not a problem.

[GlassPack]

Hell, I hate to violate the soul of my car by this I mean doing a swap, but it is the extremely rare parts. They have to be ordered from a far enough away location, and again i dont even know for sure what im buying.

Anyway, I have another question. I did some talking around and different mechanics told me that the first problem is the oil pan. what can a person do with the oil pan on a piston engine.
and my second question is this, would a four cylinder Toyota 3SGTE engine be asking for trouble, and if this was a decent engine, what about a transmission for the engine, and what would a person need to find as far as a wiring harness goes and stuff like the Turbo sensor pack (If it didn't come with the motor). Turbo Pressure sensor, AFM, fuel pump resistor packs, ick. etc etc what all would a guy need.

[rotary911porsche]

TheV8 swap has been done hundreds of times. Go to Torque Central and use the search button.
The easiest way to make certain you have everything you need for the swap is to purchase a complete running donor car. Strip the parts you need then part our the carcass. If you choose a Mustang or Camaro donor with a straight body you will certainly be able to sell it. Parting it out instead of selling it in one piece will most likely get you a profit. The sum of the parts is worth more than the whole. Your neighbors may not like a dead car sitting in your front yard. So selling it in one piece may be the best option.
If you do not have to pass smog the swap is much easier. A long block, a carb and a tranny and you are almost home. Be aware that the little things like brackets can add up.
There are several discussions on Torque Central over the oil pan issue. Search the V8 RX7 forum. It really is not a big deal.

[GlassPack]

yeah i did check out torque central a couple of times, but i cant really find the answers to the questions i have, they tell me the same things people here do.

[GlassPack]

Know what
I have decided that doing an engine swap would ruin the whole idea of my car and plus an engine swap is just more money for nothing really . If I decided to keep my rotary engine where can I learn enough about rotary engines to do all the work that has to be done to it when she decides to break down. Is there a place on the net that would give a guy an idea of a rotary engine teardown.

[DensoSupra]

Originally Posted by banditkiller

ford 302 v-8's drop in with an engine cradle made by grannys...they do alot of v6 and v-8 swaps for rx-7's

A waste and a disgrace of a good rx7...

[GlassPack]

I was wondering as far as a good piston engine goes, would a four cylinder with the right bolt ons make any power. I was wondering about a Toyota 3S-GTE four-cylinder engine. Would they make a decent engine. Would they make any power whats so ever or just speed. Also can anybody tell me what the dimensions of an RX-7 engine bay are. What are the depth, width and length of the bay.

[ldstang50]

3sgte!? thats a great motor. there are some bolt ons available, like headers cat back and intake manifolds. trd would have most of the parts
i don't know the exact specifications on the rotary motor but i have one in my room and will measure it out this weekend. email me back at [email protected]

[Steel]

Originally Posted by Entreri33

The 20b is a 300hp (mildly tweaked) non turbo engine and 600hp turbo with some serious mods .

WTF? dude, stock its a 280hp 280torque twin turbo. after you put some serious money into it (i.e. single turbo, fuel management, ect) will it be 600hp. Sure there are like, 2 20b's out there N/A, but they dont make 300 hp unless they have a p port or something ridiculous like that.

[RX_speed]

WTF?? did any body notice he said "to get a HEAD GASKET replaced"

last time i checked my rotary didnt have a head gasket

[Kaneto]

Originally Posted by GlassPack

Know what
I have decided that doing an engine swap would ruin the whole idea of my car and plus an engine swap is just more money for nothing really . If I decided to keep my rotary engine where can I learn enough about rotary engines to do all the work that has to be done to it when she decides to break down. Is there a place on the net that would give a guy an idea of a rotary engine teardown.

There aren't really any websites that show a complete teardown of a rotary, but there are a number of resources out there.

Contact Atkins Rotary. www.atkinsrotary.com. They sell videos showing the completely teardown and rebuild of the rotary. These guys are also extremely helpful and can answer just about any question you can think of.

www.rx7club.com is pretty much the largest rotary web board on the new. There's also other sites that focus on more specific models and issues, but this is a great place to start.