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Rebuilding a Rotary

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Is there anyone out there who has actually rebuilt thier own rotary engine? If so, was it difficult and has anyone seen the rebuild video put out by Bruce Turrentine?? I'm looking at a twin turbo 1993 "Cosmo" engine which is a third generation engine. Are all 1993 and above engines Cosmo engines??:feedback:

Dave Clifford

"The Metal Man" Musketeer

Vise grip hands and Micrometer eyes!!


Cozy MKIV Plans #656

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I have the video by BT. It is, IMO, a great video and makes the process look really easy....of course Tiger Woods makes golf look easy (well, when he dosn't make his ball go swimming).


I strongley suggest you get and view the video. It is a good use of your time.


All the best,



Christopher Barber

Velocity SE/FG w/yoke. Zoom, zoom, zoom.



Live with Passion...

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Im rebuilding a 13B

The Cosmo engine could be a 13B or a 20B,

They are the same design with the 20B (2000cc instead of 1300cc) having 3 rotors instead of 2. The only problem is weight and balance and different mounting strategy. As you probably know, the Cosmo is a model of car that came with several engines. I don't think it was sold in the US in 1993.

Rebuilding is EZ but be careful of out of tolerance rotors and cases. There are several sites and reputable rebuilders and parts suppliers on the web, most of them build for racing. Street porting is good, strip (race) porting will work at high RPM but has trouble at idle (taxi problems)

The rebuilding kits are easy, but be careful of do-it-yourself porting. If you have done port polishing and other intake mods on other engines, it wont be a problem though. Rotor bearings and apex seals cannot be "slopped" and there are several little tips and tricks for keeping case bolts in one piece and optimizing cooling passages.

All in all, if you have a good amount of experience in rebuilding engines (successfully) IMHO I say go fo it. If not, call Bruce. Also, I was warned about the time factor being added to the total build time. It counts as build time, and the more goodies you add (turbo etc) the more it adds to the build. Non-turbos need mufflers, turbos need intercoolers....yadda yadda yadda..blah blah blah.

I have yet to crack the case I mine but I have already done a couple of them so I didn't hesitate. I will try to add some info on my Maddy site when I get to it.

Back to building... #618 Cozy MK IV


My Cozy web pages, courtesy: Rick Maddy... :cool: WN9G :rolleyes:

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