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I got a wankel! (and why it won't work) by kwagner
Started on: 05-01-2008 10:04 PM
Replies: 26
Last post by: Isolde on 07-03-2008 12:46 PM
kwagner
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Report this Post05-01-2008 10:04 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
Well, I happened upon a 12a rotary with 5spd transmission from an 83 rx7 on craigslist for $100 (including engine stand), how could I refuse?

I know the topic of a rotary in a fiero comes up time to time (I've considered it myself), and the reason it won't work (without quite a bit of engineering) is the location of the exhaust manifold. These pictures should show why.


Note how wide near the bottom the engine is compared to ordinary inline 4's and v6/8's. Here's two pics of the 2.8 from sardonyx247's build thread to illustrate:



If that isn't enough, there's now the exhaust manifold in the way as well:


And another image straight on with the flywheel:


Even if you turn the manifold around, it's still virtually right in line with the flywheel, where the shafts come out of the transmission:
(another pic from sardonyx247's build thread):

So that's the problem in a nutshell. Hope this helps someone
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merlot566jka
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Report this Post05-01-2008 11:00 PM Click Here to See the Profile for merlot566jkaSend a Private Message to merlot566jkaDirect Link to This Post
make a header?

there is a wankel to gm trans adaptor out there somewhere. maybe it has the solution
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Report this Post05-01-2008 11:07 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeDirect Link to This Post
On the Renesis engine (Mazda RX-8), they moved the exhaust ports. Unfortunately, I haven't seen the exhaust setup up close. So I'm not sure if it has the same issues. But it's worth looking into.

BTW, do the words "twin turbo longitudinal" get your creative juices flowing?
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kwagner
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Report this Post05-01-2008 11:55 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
 
quote
Originally posted by merlot566jka:

make a header?


Here's a reference picture for how far the stock exhaust sticks out:


this is a typical header on a rotary (made by Racing Beat). I'm not sure you could get bends any smaller really without affecting performance. And these look like they will still interfere.

 
quote
Originally posted by merlot566jka:there is a wankel to gm trans adaptor out there somewhere. maybe it has the solution


Here's one I found for a powerglide tranny: http://www.eastcoastparts.c...assis_componets.html Haven't seen anything yet that would work with a transverse setup, but there's plenty out there I don't know about.


 
quote
Originally posted by Blacktree:

On the Renesis engine (Mazda RX-8), they moved the exhaust ports. Unfortunately, I haven't seen the exhaust setup up close. So I'm not sure if it has the same issues. But it's worth looking into.


I wasn't aware of that. I knew they modified the intake ports. A quick google found:
http://www.rotaryengineillu...enesis-engine-2.html
and
http://www.rotaryengineillu...enesis-pictures.html

and this picture in particular looks like the exhaust (bottom) ports are even closer to the flywheel than they are in the rx7 (where they are located where the indented circles are in the pic).

 
quote
Originally posted by Blacktree:
BTW, do the words "twin turbo longitudinal" get your creative juices flowing?


You bet

The closest thing I have seen to a workable solution would be the "plugs up" method used in some aircraft conversions:
http://www.flyrotary.com/whypu.htm
there's some additional considerations you don't have to worry about with a plane, though, like ground clearance and making sure the intake doesn't interfere with the output shaft from the transmission.
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Report this Post05-02-2008 12:52 AM Click Here to See the Profile for TKSend a Private Message to TKDirect Link to This Post
I got that Big-O feeling.
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kwagner
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Report this Post05-02-2008 06:40 AM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
Just had another thought, the th325/425 transmission that is sometimes used for longitudinal v8's:
http://www.fieroaddiction.com/SBCLa.html
https://www.fiero.nl/forum/Forum2/HTML/088579.html
https://www.fiero.nl/forum/A...041015-1-030268.html

The location of the differential is on the opposite side of the engine:

which might clear the plugs. There's another problem, though. Here's the hole that needs made for the shaft to fit under the engine (for a sbc):

which looks like it might be too high and not clear the bottom of the rotary.
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Report this Post05-02-2008 06:55 AM Click Here to See the Profile for tesmith66Send a Private Message to tesmith66Direct Link to This Post
Can it be rotated? Rotate the engine up, and the transaxle down and make a header that the axle fits through?

------------------
1986 SE 350 V8

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Report this Post05-02-2008 09:16 AM Click Here to See the Profile for DracorSend a Private Message to DracorDirect Link to This Post
 
quote
Originally posted by tesmith66:

Can it be rotated? Rotate the engine up, and the transaxle down and make a header that the axle fits through?



x2 Since you will probably have a custom adapter anyway why not make it to rotate the engine relative to the tranny. Get a dry sump oil system and your good, as long as there arn't any gravity designed engine internals. I would love to see this in a Fiero (turbo'ed)
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kwagner
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Report this Post05-02-2008 10:33 AM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
 
quote
Originally posted by tesmith66:

Can it be rotated? Rotate the engine up, and the transaxle down and make a header that the axle fits through?



I'm not quite sure what you mean by rotating up and down, but the bottom of my second post is a link to rotating the engine 90 degrees which looks like it might work. I don't right now have the fab skills to test it out, but I will be stripping down the engine sometime soon and trying a few things with it.

[This message has been edited by kwagner (edited 05-02-2008).]

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Report this Post05-02-2008 02:09 PM Click Here to See the Profile for FIEROPHREKSend a Private Message to FIEROPHREKDirect Link to This Post
G50 trans . No need to thank me

------------------

ARCHIES JUNK IS FASTER THAN SHAUNNA'S JUNK

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Report this Post05-02-2008 02:51 PM Click Here to See the Profile for americasfuture2kSend a Private Message to americasfuture2kDirect Link to This Post
wow, this looks like you have gotten farther than me on this subject. you have a rotary in hand to play with. will that powerglide adapt plate fit the getrag? i can get a rotary to play with, but its a street port or some kind of port (its heavily modded). it was rated at the wheels around 450hp. the person who owns it is getting a 20b built. i would love to buy his 13b to make this happen. hes asking $6k for the motor. i wouldnt wanna pay that price just to fck something up and ruin a perfectly good $6k motor in just some test fitting.

sorry if this sounds a bit rushed and all that, im at work with fckers coming in left n right asking for things. lol you can tell i like to be left alone at work.
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kwagner
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Report this Post05-02-2008 05:44 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
 
quote
Originally posted by FIEROPHREK:

G50 trans . No need to thank me



And they're so affordable, too!

Actually, I just got back from a salvage yard and while I was there was perusing the transmissions they had, and came across one from an 89 eagle summit that had the output shafts on the opposite side. I did some looking online and it seems that at the very least all the DSM (laser, talon, eclipse) FWD cars were set up this same way:
here and here and here for examples. I'm not sure if the engine would be spinning the correct way, though.

 
quote
Originally posted by americasfuture2k:

wow, this looks like you have gotten farther than me on this subject. you have a rotary in hand to play with. will that powerglide adapt plate fit the getrag? i can get a rotary to play with, but its a street port or some kind of port (its heavily modded). it was rated at the wheels around 450hp. the person who owns it is getting a 20b built. i would love to buy his 13b to make this happen. hes asking $6k for the motor. i wouldnt wanna pay that price just to fck something up and ruin a perfectly good $6k motor in just some test fitting.

sorry if this sounds a bit rushed and all that, im at work with fckers coming in left n right asking for things. lol you can tell i like to be left alone at work.


Yeah I figured for $100, it'll be well worth it to do a few experiments and satisfy my curiousity I'm not sure if that adapter plate would fit the getrag. At the very least it looks too wide and would have to be trimmed down. There's lots of nice rotaries out there, and a number of porting options for more power. here's a list of them with pro's and con's. 20b's =
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Report this Post05-02-2008 07:00 PM Click Here to See the Profile for americasfuture2kSend a Private Message to americasfuture2kDirect Link to This Post
oh i cant wait to hear that 20b startup. i think having a rotary in a fiero kitted out as a ferrari would be a good mix n match. to some people, they might beable to tell its a kit car. but with the sound of a rotary, it wont sound like any usual kit car. fc355 kit...come to me!.....
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Report this Post05-02-2008 10:57 PM Click Here to See the Profile for cardealerSend a Private Message to cardealerDirect Link to This Post
Ive seen those pics somewhere before..........
 
quote
Originally posted by kwagner:

Just had another thought, the th325/425 transmission that is sometimes used for longitudinal v8's:
http://www.fieroaddiction.com/SBCLa.html
https://www.fiero.nl/forum/Forum2/HTML/088579.html
https://www.fiero.nl/forum/A...041015-1-030268.html

The location of the differential is on the opposite side of the engine:

which might clear the plugs. There's another problem, though. Here's the hole that needs made for the shaft to fit under the engine (for a sbc):

which looks like it might be too high and not clear the bottom of the rotary.


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kwagner
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Report this Post05-03-2008 03:54 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
 
quote
Originally posted by cardealer:

Ive seen those pics somewhere before..........


Nice car you got there, cardealer. Thanks for documenting the process

There's currently a thread about extending the differential past where it normally connects to avoid cutting the oil pan, which could make the th325/425 viable for use in a rotary swap.
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kwagner
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Report this Post06-06-2008 12:00 AM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
Came across this today, a possible (cheaper?) alternative to the G50, converting a subaru awd transmission to fwd:
this company supplies a kit, although a bit pricey for what's provided in my opinion. I do know people have made their own. Found this on a dune buggy forum, thread here. A couple posts down the thread is a link to the pdf of the instructions to do the conversion.

Edit to add:
The other bit of research I've been doing lately is on mitsubishi eclipse and 3000gt transmissions, which appear to have the transmission on the opposite side of the engine. I'm not sure yet if the engine rotates in the opposite direction, or if it's "normal" and the gearing of the transmission makes the switch. Having a hard time finding good pics/info, anyone have either vehicle and could check for me (or any other vehicle with a transmission on the opposite side)?

[This message has been edited by kwagner (edited 06-06-2008).]

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Report this Post06-06-2008 07:09 AM Click Here to See the Profile for tesmith66Send a Private Message to tesmith66Direct Link to This Post
Are you gonna change your username to Kwankel?

Sorry, I'm in a goofy mood.

------------------
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kwagner
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Report this Post06-06-2008 08:24 AM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post


I also was planning out how to do engine management. The 1983 12a was originally carbed. Would the TBI system from a 2.5 duke work? Since the 1.2L wankel is "basically" equivalent to a 2.4L piston engine, the fuel requirements I would think would be similar to a duke. Fab up a small upper intake manifold to bolt up to the existing one on the engine, and add appropriate ports for map, temp, etc. It would keep the existing distributor for proper firing order, so it would have to be an earlier duke setup. I'm not sure though if the spark will happen every time the distributor says to, or when the ECM decides to (ie changing the timing). I know some rotaries have been converted to EFI using megasquirt, I was wondering if there was a simpler way for a fiero. Any thoughts?
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Report this Post07-01-2008 10:27 AM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
Well had a few PMs back and forth about various reasons why the TBI on a 2.5 probably wouldn't be a good idea. Anyway, on to more important news:
Came across this while browsing some on rx7club, a rotary converted fwd civic (via hondatech). Although I doubt the 800hp claims, it's interesting for keeping the honda transmission, and I believe a stock turbo exhaust manifold (after that point is custom fab, of course). I can't tell from the pics if it's just luck that the transmission has its output shaft higher, or they rotated one or the other slightly to accomodate.

Also check out halfway down this page to see a rotary mini. A little more info here.

And also this fwd conversion. Check out that exhaust clearance
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82-T/A [At Work]
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Report this Post07-01-2008 10:57 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Direct Link to This Post
 
quote
Originally posted by kwagner:

Well, I happened upon a 12a rotary with 5spd transmission from an 83 rx7 on craigslist for $100 (including engine stand), how could I refuse?

I know the topic of a rotary in a fiero comes up time to time (I've considered it myself), and the reason it won't work (without quite a bit of engineering) is the location of the exhaust manifold. These pictures should show why.


I've got to ask, why would you consider a 1st generation RX-7 rotary motor? I've seen them hopped up, and with plenty of boost, but... with all of that work, people typically only get mid 14s from a 1st gen RX-7... and that's with a LOT of work. The 1st gen RX-7 is a very light weight vehicle... it weighs a good 175-200 pounds less than the lightest Fiero out there. If you were going to do an engine swap, you'd really need to go with at least a 13b motor.

I had an 88 Turbo-II back in the day, and honestly... in totally stock form, my 88 Turbo-II 5-Speed wasn't that much faster than a totally stock V6 Fiero with a 5-Speed. I really did like the car (black inside and out, with a CD player, sunroof, and a leaf catcher in the front). But despite all the fake times flying around... you usually got a mid 15 second quarter mile on a good day (as apposed to a high 15 second from a 5-speed V6 Fiero, or God forbid, a low / mid 16 second from an automatic Fiero... heh).

I'm not trying to discourage, I'm simply stating that if you're going to do it, you should really consider starting with better components. Consider this. If you pulled EVERYTHING from a totally STOCK 1987-1990 Turbo-II, you would basically be running the exact same times. The 2nd gen RX-7 weighs nearly the same as a Fiero does.

if it were me, I'd look for a wrecked 3rd gen to make it worth your while.

You don't want to have to spend tons of money to hop up a motor only to have it basically run mid 14s and be fairly unreliable. Just my opinion.

Otherwise, I think if you had a "cleaned up" 3rd gen rotory in something like an 88 Fiero Formula, it would totally scream and would be awesome.

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1981 EZ-GO Xi875-A "Miami Dolphins" Medical Cart
1973 Volkswagen Type-2 Transporter

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Isolde
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Report this Post07-01-2008 12:54 PM Click Here to See the Profile for IsoldeSend a Private Message to IsoldeDirect Link to This Post
I have a possible solution. If you look under the hood of an '89-'95 Eclipse, you'll note the Transaxle is configured opposite of the Fiero setup. The catch is that you would need a custom adapter plate made.
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Report this Post07-01-2008 01:15 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
 
quote
Originally posted by 82-T/A [At Work]:


I've got to ask, why would you consider a 1st generation RX-7 rotary motor?


I'm just using the 12a for testing stuff. It was cheap ($100), came with tranny and engine stand, and I wanted to try some experiments on it. Buying a wrecked 3rd gen is a bit more expensive, especially for something you don't even know whether it would work or not. If I had unlimited funds, and figured out how to get the wankel in there, I'd end up doing a 20b

 
quote
Originally posted by Isolde:

I have a possible solution. If you look under the hood of an '89-'95 Eclipse, you'll note the Transaxle is configured opposite of the Fiero setup. The catch is that you would need a custom adapter plate made.


A custom adapter plate is already necessary, so that's not too big a deal. I did do some research earlier and found the reversed position of the eclipse tranny, but I am unsure on whether the engine rotates normal or in the opposite direction relative to the 'normal' (in our case GM) engine. I know looking from the front (pulley) side, the wankel rotates clockwise, with the intake and exhaust on the left, and spark plugs on the right. Searching the net for info that vague didn't result in much. Do you know?
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Report this Post07-01-2008 02:05 PM Click Here to See the Profile for IsoldeSend a Private Message to IsoldeDirect Link to This Post
wow, do I feel dumb. I never stopped to consider if the Eclipse runs what us GM guys consider standard rotation or reverse, and this seems critical. I guess someone needs to watch a driveable Eclipse crank over and see. Maybe if anyone knows of an Eclipse forum, or has a girlfriend who drives one? An alternate is if you find an Eclipse at a salvage yard, with it's engine out, put Vise-Grips in the input shaft, put the 5-speed in gear, and try it. Less easy, but more likely, is if the thing has wheels, put it in First, have one friend on each wheel, while you watch the crank pulley. Sorry I can't offer anything better.
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Report this Post07-01-2008 04:03 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
Hey, no prob. We're all learning here I wouldn't have thought of it except I read about earlier hondas having reverse-rotation engines.
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Report this Post07-02-2008 01:51 PM Click Here to See the Profile for IsoldeSend a Private Message to IsoldeDirect Link to This Post
Yesterday I posted on 2 Mistubishi forus, and they say their rotation is clockwise, so you're good there. Maybe you can tell I'm intrigued.
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kwagner
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Report this Post07-02-2008 03:37 PM Click Here to See the Profile for kwagnerClick Here to visit kwagner's HomePageSend a Private Message to kwagnerDirect Link to This Post
Thanks for the info, that's farther than I've gotten
My next paycheck I may take a jaunt down to the yards and see what I can come up with.
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Report this Post07-03-2008 12:46 PM Click Here to See the Profile for IsoldeSend a Private Message to IsoldeDirect Link to This Post
My local yard sells those transaxles for around $110, and there's usually more than one. I know because I'm always looking for the turbo from an Eclipse. Actually, I need two, but that's off topic.
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