Need a little help going 13B-REW rotary - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to   Members

DIY Turbo Discussion greddy on a 1.8? homebrew kit?

LinkBack Thread Tools
Old 02-21-2009, 10:07 PM   #1
Thread Starter
Join Date: Jun 2008
Location: CA
Posts: 9
Total Cats: 0
Default Need a little help going 13B-REW rotary

Well after blowing the head gasket on my 1.6l I have come to the decision to go to a rotary set up. I know I know lots of fab work but in the end it's going to be pretty sweet. It's a Gotham race ported 13B rotary. I bought the motor from a buddy that is putting a built LS3 plus a 400hp shot of spray in his 93 FD. The question is I don't know if the bolt on the crank is a left or right hand thread. It's on tight as hell and I don't want to hit it with an impact gun and break it. I will be posting lots of pictures! I'm really excited to get going on the project!

Any help would be great thanks hans
209miata is offline   Reply With Quote
Old 02-21-2009, 10:17 PM   #2
Junior Member
Join Date: May 2007
Location: San Diego
Posts: 383
Total Cats: 0

jobambo is offline   Reply With Quote
Old 02-21-2009, 10:20 PM   #3
Junior Member
Join Date: Aug 2008
Location: BC, Canada
Posts: 58
Total Cats: 0

Which bolt are you talking about? The one on the front pulley of the 13b?
boosted7 is offline   Reply With Quote
Old 02-21-2009, 11:05 PM   #4
Thread Starter
Join Date: Jun 2008
Location: CA
Posts: 9
Total Cats: 0

The one on the front. I just need to get the cover off one of the oil pan bolts broke and I need to re tap it
209miata is offline   Reply With Quote
Old 02-22-2009, 12:39 AM   #5
Cpt. Slow
iTrader: (25)
curly's Avatar
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 12,110
Total Cats: 518

wow you're stuck on the first bolt, off to a good start.

Do a search, we're not big on rotary swaps. Not that we don't like rotary engines, but no one's really done it here, so you're not going to get a lot of knowledge from us unless its for the miata chassis. I think has more rotary swaps than here. But sucks, so...yeah
curly is offline   Reply With Quote
Old 02-22-2009, 01:05 AM   #6
I'm Miserable!
iTrader: (16)
Join Date: Dec 2008
Location: where most people are Utarded
Posts: 1,323
Total Cats: 0

oh boy....
zoomin is offline   Reply With Quote
Old 02-22-2009, 03:58 PM   #7
Junior Member
Join Date: Aug 2008
Location: BC, Canada
Posts: 58
Total Cats: 0

Seriously dude, anything rotary specific you'll get a faster(and usually better) via
boosted7 is offline   Reply With Quote
Old 02-22-2009, 04:17 PM   #8
Elite Member
iTrader: (24)
kotomile's Avatar
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40

You're having reliability issues, so you want to swap in a rotary?

You won't find much useful info here (maybe a tiny bit, but not enough). I suggest you get on roadsterdrift forums or clubroadster for rotary-swap-into-Miata info and RX7 forums for anything rotary specific.
kotomile is offline   Reply With Quote
Old 02-23-2009, 03:53 PM   #9
iTrader: (2)
Join Date: Nov 2008
Location: Atlanta-ish
Posts: 32
Total Cats: 0

The crank bolt is a normal thread - that is it turns counter clockwise to loosen it.

Yes, it unbelievebly tight because, if installed correctly, it has loctite on its threads.

Standard procedure is to heat the head of the bolt for up to 2 minutes with a propane torch to get enough heat down to the threads to relese the loctite.

While respected rebuilders do this it scares me to heat engine parts. I lock the flywheel and use a torq bar with an extension pipe to loosen the bolt. It is so tight that you can jump on the bar with your full weight (230 lbs here) 18-24" off center to loosen the bolt. Once broken loose removal is easy.

BTW, having owned abpout 20 RX7s from 1978s to 1991s both na & turbo I believe that most 13bs now on the road are well worn and relatively poorly maintained - thus are high risk engines. Having done all kinds of piston swaps into rx7s I would not consider moving a 13b into a Miata due to the very high cost of refurbing a 13b to what I consider reliable condition.

Good luck either way - if adventure is your goal I am sure a rotary swap will be a blast. They do rev even higher than Miata motors and are smooth!
Floored is offline   Reply With Quote
Old 02-23-2009, 04:42 PM   #10
Join Date: Dec 2008
Posts: 17
Total Cats: 0

Ok I know all about this! First you have to decied cheap route with a carb or expensive route running a turbo!

You will need:

-Front casing from a 12A if you go carb'd route
-Entire front clip if you plan on running boosted
-Custom exhaust
-New Driveshaft (if you have an aftermarket diff)
-New Diff, if running weak stock on (maybe you can score a complete donor RX7?)
-Modified Subframe
-Modified Engine Mounts
-Modified Oil Pan
-Transmission subframe
-Diff Locater
-Modified Slave Cylinder
-Modified rear axles

Reccomended Upgrades for boosted apps:

-Modified fuel line
-Modified brake lines
-Modified coil mounts
-Modified Radiator Brackets

Power steering is NOT an option with this upgarde nor will it ever be, sorry!

The modified subframe and engine mounts can be custom fabbed but its not for a DIYer that doesnt have a little skill as the vehicle will have to pass a VI to be road legal, atleast its like that up here in Canada. used to sell a complete kit for a couple thousand that was a really nice piece dont know if its still available though.

We went carb'd just for the fact it was going to keep costs fairly low and the nightmare of hooking up a method of ignition on a EFI system is well long, complicated and were a bunch of lazy canucks!

Final out come was a 1992 NA with a balanced and blueprinted, bridgeported 13B with a 46IDA webber carb providing fuel control. The car has never been dyoned but its figured to be making ~200HP at the wheels with the capability of revving to 11,000RPMs
cost was about $6000CDN and took a little over a month to complete.

The rotary engine isnt more unreliable then any other engine it just requires more maitnence then a standard boinger engine because of the mechanics of the engine, also the rotary serves more of a purpose as a race engine it likes being abused within its limits. Also if you do this conversion be sure to remember the engine will always burn oil so keep up on that!
twistyz is offline   Reply With Quote
Old 02-23-2009, 09:35 PM   #11
Elite Member
iTrader: (4)
Join Date: Sep 2006
Location: Charlotte, NC
Posts: 3,054
Total Cats: 8

When I was taking apart my 13b engine I took it to a place that worked on heavy equipment and had them use one of there big 3/4" drive torque guns on it.

Made quick work of that puny nut...and they didn't charge many anything.

Well worth the trouble of throwing the shortblock in the back of the CRX and driving there. Saved me from a lot of swearing and possible injuries.
Efini~FC3S is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
EMB 1993 1.6L initial setup rotary switches positions E-Manage 6 09-13-2011 04:55 PM
Rotary Miatas list? mackmiata Engine Performance 7 01-23-2011 12:49 AM
ROTARY swap Steiny General Miata Chat 124 03-31-2010 01:11 PM
Mazda Rotary Watch on eBay mrtonyg Miata parts for sale/trade 0 11-11-2008 05:53 PM

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -4. The time now is 07:16 PM.