Rathmysphs

Ok, i've been watching these forums for about two months now. I feel it's about time I start asking questions That weren't answered. (ALL of them were answered about the 13brew engine by searching and back-reading, a wonderful library here) What I havn't seen here, but I have seen in magazines and at a show once is the sr conversion. I race a G20 with an sr and drive another one daily. It's about time I grow up a little more and go RWD. Because I'm about to lose a car to full track time my next project is going to be a daily for 18 months or so before it also hits full track status. I am an NA racer. I don't go for any show, and I drive around on B+G race R2 coil-overs. I'm not here to look good, I'm here to hit that corner as fast as possible.

but to the point. I'm doing another SR build-up and It's going to be for a RWD car. I hate the 240sx because of the scene it's associated with. The rx7 doesnt have that same scene because, well, it's F*cking expensive. dumbass kids can't afford it. The engine in question to be dropped into a RWD (possibly rx7) is an SR16VE bored and stroked to a fat 2.2L with minor headwork, only springs. retainers, solid lifters, and a slight valve job. the stock sr16 cams will hold out in this engine til it his full-time track. If you don't know much about the SR or non-magical-triangle power engines this is going to be a HIGH revving NA engine. like my other one. but cooler. about 2k rpm cooler. Right now the block is being re-sleeved. the engine will be finished around december, so I have some more time to decide on what to drop this into.

I'm basically looking for someone I can talk to about doing the SR swap. I'm friendly, and I won't bite. Anyone want to be my friend? Figuring out how reasonable it is to put this into an rx7 is important to know before I buy a shell.

Thanks all, you have a good forum running.

danameisoj

iTrader: (6)

intresting idea but not many people like putting an ls1 in the fd let alone a 4banger.

if your thinking about the rx7 .. keep it in its true form and go from there .. the 7 is a remarkable car for its handling . pieced together with its original engine ...the possibilities are endless

Rathmysphs

One of my friends likes to bring his mostly stock 94 r2 to the track. it is amazing and wonderful, but I am about keeping the 50/50 weight and I'm a pure bread NA junkie. as amazing as the 13brew is I need something that can get beat up daily and not set me back on buying a house. I priced out the work I would have to do to the 13b to make it as reliable as I require and it was around 12k. I can build my sr engine for 4k. But, i need another 2k to build up a s15 tranny, and a saftey net of 3k just because shtuff happens. 9k with 3k of safety or 12k +/- who knows. I'm not about tradition. I'm about making something my own. a lot of people get angry with me about some of the things I've done. I'm sure if I do actually put a 4banger into a 7 I'll get a lot of negative comments. But I think the two will match up well on a tight technical infield. nothing wrong with revving to 11,2.

The handling of a 7 is what has kept me drawn to it. a simple tien SS EDFC, poly bushings, and the different linkages and stb's make the car AMAZING! It pisses me off when my race car gets over-taken in a turn. really pisses me off.

edit: spellcheck and forgot to mention suspension.

danameisoj

iTrader: (6)

i do see what your saying .... reliability and affordability would be nice..

good luck with what you do.. i also would suggest a look into other engine conversion section .. i believe i saw something on and sr swap.

KeloidJonesJr.

iTrader: (8)

G20s are FWD. I don't see how that would work. Why not just put a turbo kit on it?
*edit what the hell I didn't get your question.

apex_sideway

Ah, alot of us on this forum are rotary purists and finding anyone to help you with this swap will be difficult. Good luck! It should be a unique swap.

Rathmysphs

I tried really hard to stress that I am an N/A guy. yes, g20's are FWD, yes, the sr engine can go both ways. it's even used as an AWD platform in the hp10 primera. They're awesome engines. very tourque for N/A, not very expensive. the 7 can handle. really well. has a 50/50 weight distrabution. If i put in said engine, I can have the NA performance I want, with the handling I desire. if you rotate a FWD engine 90 degrees, it becomes a RWD engine. the SR block bolts up to the 240sx/silvia transmission which is a RWD tranny. a simple custom driveshaft connects it to the diff.

A lot of people don't get why some people want N/A so bad. I desire the response it has. I also like the power curves. also, do you know what it sounds like when I shift up at 10k RPM? Think F1. F1 and P1(except for the audi deisel) are all N/A. That's the preformance I want.

It has nothing to do with making numbers or big power. Straight lines are for suckers.

Rathmysphs

I'll have to try looking some more. I'm glad you get 'it'. So many people I know question everything I do, and why a FWD N/A car that makes half their power leaves them in it's mirrors on a track. When people understand I get a sigh of releif.

SiKoPaThX

iTrader: (2)

Search the Other Engine Conversions section of the forum:

https://www.rx7club.com/other-engine-conversions-non-v-8-118/

There has been at least 2 SR20DET conversions into RX-7s that I know of. There should be some info in there.

For the rest of you idiots, if you don't have anything helpful to post, don't post at all. You drive smart, educated enthusiasts like this guy away from our forum and spread a rumor that RX-7 owners are a bunch of wankel-sucking group of rotor-*****.

Hope I could help you buddy.

Edit: Here are 2 threads that hopefully help a little.

https://www.rx7club.com/showthread.p...highlight=SR20

https://www.rx7club.com/showthread.p...highlight=SR20

Rathmysphs

Thank you so much for your help Sikopath.

Tanjo

Im all for it. But. How much power is you SR going to put to the wheels? I cant see an NA 2.2L making more than 225-250, unless your running like 13:1 or more on alcohol or something. The power output, coupled with the peaky power band that I imagine your motor is gonna have, seems like its gonna have a tough time pushing the FDs 27 or 2800 pounds around. Dont get me wrong, I love my FD, and am not calling it fat by any means. Its lighter than all the cars in its class. But, its no featherweigt, compared to other cars that would be more apt for this kid of swap, IE FC, FB, AE86, 510 etc. I mean, its not gonna be super slow, and its still gonna handle like nuts, but Ill bet that its gonna be signifigantly slower than stock. I would suggest throwing the motor in an FC. Lighter than the FD, but wuite a bit, and can still handle beautifuly. Although I could see how you wouldnt want to do it, based on looks alone.

just my 2

antiSUV

iTrader: (10)

One lead you might try in researching this swap is the miata.net forum. The Miata uses a PPF that is similar to the FD one and I know there have been a few SR swaps into Miatas. You may be able to find some links to pictures or other hints on how people managed to mate the trans you are using to the stock PPF, fab a custom PPF, or eliminate it altogether.

BTW, I also support this venture. Good luck!

Rathmysphs

thanks for your help guys. I'm actually going to be using a 6 speed tranny from an S15, it's a great tranny, that happens to bolt to the SR block. Yes, it is high compression. 12.1:1 apprx. It moves my 2650lb car with lots of wheel spin(yeah, i know, FWD) the sr I have right now puts out about 255hp/262tq. I should find my dyno and scan it. My next engine will be stronger and rev higher. It's actually a very smoothe power band. and it's very wide. I'm looking at the miata swaps right now and I'm trying to figure out how I would mount it in an FD. My driving style is one based on momentum. I am looking at a few other cars that are lighter, but I've had an FD obsession since '01 and I can afford to make an FD race car this way that actually might fit me. It's about making something work with me rather than for me. I'm just weird or something I guess. who puts an N/A four-banger into an FD?

scotty305

iTrader: (2)

If you're a fan of high-revving N/A power, you'll need a lightweight chassis to compensate for the lack of torque compared to a forced-induction or big-displacement engine. The FD3S is a good chassis, but it's not quite light enough (2800lbs) for what you're doing. From what I saw, the G20/Primera weighs between 2500-2900 lbs, depending on the year. Assuming you're racing the lightest G20 available, the RX-7 chassis will be heavier than what you've already got.


I'd suggest that you look into the Miata. Unless you've got a ton of spare Nissan parts lying around, you're not going to find a better N/A bang for your buck than the Miata. The early models (1989-1997) weighed about 2100-2300 lbs, and you can cut plenty of weight if you're going to prep the car for roadracing. The aftermarket support is great, and Mazda's racer support program is great. You can get factory parts for cheap through Mazdaspeed NA: www.mazdamotorsports.com

There are spec Miata divisions, where you can build a competitive car for relatively cheap.


Unless you've got a ton of Nissan parts lying around that you're not able to sell, I think you'd be wasting your time building a non-turbo FD3S. There are a lot of people buying RX-7 chassis for V8 swaps, so it's not going to be easy to find one for cheap. There were less than 14,000 FD's brought to the U.S, and less than 10,000 are still registered for street use as of October 2005. Compare that with the 700,000 Miata's out there (not sure if that's worldwide or US only, but I can guarantee there are more Miata's out there than G20's and FD's combined).


Best of luck,
-s-

edit: I'd really like to see that dyno chart, and know the SR20's engine weight. The 13B-REW weighs between 300-400lbs including all the accessories (turbos, IC, P/S, etc...)

PhatManBUD

dont ruin another FD, buy another car

OneRotor

iTrader: (3)

9k with 3k of safety vs. 12k +/- who knows. You're right about this one, but have you thought about all of the custom fabrication that you're going to have to do, let alone adapt the FD harness to the SR sensors, and then figure out a way to let the computer make sense of them. The swap will run you between 15 and 20k after all is said and done. Your 9k estimate for the motor, is that just motor, or is that with computer and tuning and everything?

I'm not trying to **** on your cornflakes, but there is more to the swap than just building a monster of a N/A 4 banger. Good luck. Keep us updated.

JustinStrife

iTrader: (2)

If you don't have anything constructive to say, don't say anything at all.

To the thread maker: Just go with an LS1. A stock LS1 will give u 300rwhp give or take, and not affect the handling at all, if you do the conversion right. Plus you'll get great realiability, 30+ mpg on the freeway, and a very smooth powerband.

F0RSAKEN

While Im not a huge fan of small displacement N/A engines, it sounds like an interesting idea.

To all the people saying the FD chassis weighs too much...look at LUPE's car. Id think if you made it a race car, you could knock the weight down to ~2300-2400lbs, and 250hp would move it quite nicely.

PhatManBUD

Its called constructive critizism buddy.

The car already comes with everything it needs to whoop ***. If reliabilities your problem, 1. dont go cheap on stuff, 2. dont half-*** stuff, 3. Get a reputable builder/tuner, and 4. Dont treat the car like ****.

Its nice knowing the cars known for being unreliable. Keeps retards from buying the car cause theyre scared of the problems. Once the idea of swapping pistons into the car gets out to everyone in the public, it gives those retards a green light to buy this "purdy car" and drop a piston engine in it to make it reliable.

All i know is that one day when the time comes, god forbid, if my FD gets really messed up, when i go to buy another one i dont want to look through one page on autotrader and have 3/4s of the FDs already have v8s in them.

If you really like the car, then like it for what it is, and deal with it. It makes me feel like a real billy badass driving it with the bad reputation is has, yet i must be one crazy mother ****** to do so.

Ya ls1 whatever whatever, but 4banger N/A gimme a ****** break. go get an s2000

JustinStrife

iTrader: (2)

It's his car to do with what he wants. And the Japanese have been doing crazy things to their cars since long before you and I heard about RX7s'. Go on cardomain.com sometime and see how many RX7s' with body kits, neon lights, huge wings out the back, and half the interior ripped out. I'd rather have a V8 or 4cyl powered FD with the rest of it intact, than a rotary powered FD, with half of the car's characteristics ripped out. Engines can be swapped back in. Bodies are hard to get back to original.

Also, what's wrong with wanting to take a great car, and make it better? Everyone has their own opinion of how to make the FD better. His is 4cyls, mine is lightweight V8's, and yours is keeping it rotary. We all have a different approach with how we look at our cars and want to improve them, but the end outcome is the same, is it not?

rynberg

Please start a fresh thread in the proper Other Engines sub-forum.

Healing

To the thread creator:

Why not look into an N/A 13B? They are crazy fast once you start dipping into the bridgeport/peripheral port ends, not to mention they've got the the unique smoothness and responsiveness that you can only get from a rotary. Hell, an N/A 13b buildup should even be cheaper than an all out SR20 buildup. While you're at it, why not look at the FC chassis as well?

My real question is why you're so adamant on the SR20 platform. I mean, sure, it's a good motor, but is it really so good that you have to swap it into every other car that you decide to buy?

GtoRx7

iTrader: (5)

I'm with this guy on the subject. I've built N/a 13b's with 190-200rwhp on shoe string budgets for ***** and giggles in daily drivers. I bet 2k would build the motor, and nearly have standalone too. But if your going to spend 12K, do what I did, build a n/a 3-rotor and have 350rwhp/ 2600lbs. Stock trans and all.

Rathmysphs

I have many of the parts already, and the expirience of working with them myself. It's an obsession I need to kill, but the 86 is going to be full track sometime mid summer probably. full guts and re-builds are a lot of work. sounds like most of you know where I'm coming from. I might buy a 95 r2 from a friend who's done a 99spec conversion. even the motor is a 99jdm with the twin high-outputs. Dunno what I'd do to the car other than some suspension mods. that's if I buy it.

edit:

I just realized this thread was re-opend or moved or whatever. I started a second one because this was closed. I ended up buying an AE86 with blown motor/tranny and I'm dropping the SR into that. Since I already have most of what I need for that swap it's pretty cheap, leaving me room to buy an RX7, like the one I talked about earlier in this post.

NOPR

you beat me to it!

3 rotors are very capable of revving to 12k if you really want to. Way more power than a 4 cylinder, way more torque, MUCH better sound, and its still a rotary!