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Newbies: Pistons engine in FC

06-17-2007, 10:26 PM
Hi all,

I'm kind of new into Rx7 and I'm about to start a projet and the FC has come in my mind. The only prob is that Rotary engine are rare and not a lot of mechanician (sp?) know about thoses. So I would like to know what kind of piston engine would be nice to swap into a FC while keeping a good weight distribution (maybe not 50/50, but the closer, the better)

I have the CA18DET and the SR20DET in mind... opinions and suggestions are welcome.

(Sorry for my english)

06-18-2007, 12:49 PM
Where are you located? Honestly the only swap that is cheap bu will knock the weight distribution is the Ls1 aka 350. It really isn't that much difference in weight shift though. There are tons of rotary guys out there and trust me the rotary is way more fun and easier to work on then you might think. A TII engine is not hard to get or an N/a 13B either.

06-18-2007, 05:32 PM
I live in Quebec, Canada

My dream car is a FD but I know I will not have the buget to have one soon. However, the FC is nice and can make a nice sleeper and they're kind of rare.

I'm not the best in rotary through and I've heard a lot of prob about them...So I'm kinda scared (maybe because I've never own one) That's why I would thinks of the swap.

But, if you tell me that rotary are not that bad...and are easy to work (even for a newb in mechanic) I may keep the 13b.

Thanks again!

06-19-2007, 09:32 AM
First things first you NEED to join Rx7club. It helps ALOT they can almost always walk you through any problem and if it's bad enough usually someone local can stop by and help you out. There are a lot of people in Quebec from what I've seen on the boards so you definetly have help close.

Btw ~ Project FD's aren't that expensive for a roller is like 4k-6k for a decent one. However those are rolling chassis a 13B-rew can run a good 3k for everything harness and all.

The best part is the redline 9K all day and once you go turbo you can push boost numbers that most pistons can only dream of. My new single I'll be running 20 - 25 psi conservatley tuned probably 35-40 on race gas at the circut.

06-19-2007, 10:20 AM
Thanks a lot!

If people give help like you did on Rx7forum, I want one just to be helped!

I'm going on Rx7club!

Thanks again! And BTW, nice FD:grinyes:

06-19-2007, 12:52 PM
350 Chevy in an FC is the only way to go, you can make gobs of power and a 350 is cheaper than a rotary motor by a long shot, even an iron 350 isn't that heavy if you have an alumminum intake, headers, and maybe alumminum heads. Rotaries are fun and sound cool but they are expensive when you get into the high HP numbers. Check out and Grannys Speed shop for some info on RX-7 V8 swaps. Either way good luck on whatever you decide to do.

06-19-2007, 01:41 PM
My name on the seven forums is FD3S4E ~

The 350 is cheaper to an extent but the overall conversion is costly when it comes to engine mounts + Tranny + Ecu + guages is a pain imo. Other then that you have a very reliable fast car. Depends on ho0w many miles are on the 13B. N/A rotaries are very reliable when done right.

And Thanks she is going to look alot different soon :D

06-19-2007, 06:52 PM
n/a's are cheap as fuck. and easy as hell to work on. oil changes take less time than on a Honda.

Honestly though, swapping to another motor just because you heard some old wives tales about the rotary isn't really a good reason to swap, especially since you've had no experience with the car at all.

Though swapping to a 350 is the way to go if you do go that route, to reiterate what was said earlier, for emphasis.

10-04-2007, 12:34 AM
Don't do the swap, rotary will be much better to you and they are pretty simple machines to learn.

10-04-2007, 01:45 PM
There's a site on the web that has a full walk through of a kid that converted an '86 and then one other RX7 over to V8. I tried to google it for you, but I couldn't find it. Sorry dude...
But yeah, Rotary engines aren't that scary. Sure, they need the rebuilds, but I did the math and (atleast for me) I only need to sock away about $100/month MAX to rebuild a modded rotary every 5 years.
As for working on one, they have like what- 2 moving parts:iceslolan ? I worked on one in my uncle's shop and fell in love with it. Cylinders confuse me... i'm a simple man.

If you want to do the conversion- it's a cheap way to save money on repairs and gain HP. But us rotary guys win out in the end, because we keep the true nature of the car.

10-04-2007, 10:36 PM
No piston engine can redline (PINNED) at 9+K for 10.01 minutes and not even half. Google or youtube it, it's amazing to see how much abuse it can take.

Btw ~ It's 3 moving parts :grinno: An inline 4 has 41 moving also just for reference...

10-11-2007, 05:09 AM
No, there are piston engines that can take that kind of abuse and guess what they are called a Small Block Chevy. But honestly why would you want to turn that much RPM if you don't have too? The beauty of a Chevy is that you have the cubic inch to make power at low RPM. Go with the Chevy, easier to work on more parts available, and overall just a better motor.

10-11-2007, 06:18 AM
They make more low end power yes but they are a bit heavier and your still fighting the most basic principal of mechanics. The more moving parts you have the more that can go wrong thats why I stick with rotaries.

Imo ~ I don't think a small could EVER handle 9k for 10 minutes without bending a valve or frying a lifter. I'm talking about 9k NON stop no throttle retention :wink:

10-12-2007, 01:28 AM
N-A-S-C-A-R, ther do it every day on 390cfm four barrels. The rotary is a simpler beast but the damn thing still breaks all the time so simple isn't always the solution. And again why turn 9k when 5.5k makes you the same power in a different mill.

10-12-2007, 10:50 PM
Redlined saved my ass when I was in a close battle with an E46 M3. I won simply because I had less shifts really...

Not for anything but it costs WAYYY more money to make a small block capable of reving out and taking a beating the same as a rotary. You'll be out $ before you know it. My friend told me a nascar block for his car from mopar is 10K alone.

10-13-2007, 07:01 PM
Which is why you don't use the an aftermarket block anyway. And again why turn 9.5k when you don't have to? An LS out of pickup makes more power stock than even a twin turbo 13B and more importantly it has loads more torque. I've a solution to the shifting problem as well, an automatic transmission.

10-15-2007, 11:14 AM
Which is why you don't use the an aftermarket block anyway. And again why turn 9.5k when you don't have to? An LS out of pickup makes more power stock than even a twin turbo 13B and more importantly it has loads more torque. I've a solution to the shifting problem as well, an automatic transmission.
Thats great but aren't you FF? :lol:

10-15-2007, 03:56 PM
No, everything I own is RWD.

10-20-2007, 03:27 PM
wow e-cock swinging going on in here.

anyway, my take on it is, why swap to a different engine, you can make power with a 13b (plus personally I'm too lazy for that shit), but if you feel like it go right on ahead.

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