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65pb736
10-21-2011, 11:12 PM
Well here we go! The start of a new project. Where to start? Very simply I'm going to put a 20B in a AC Cobra replica. :sifone: i know, it sounds weird, but it really makes sense. My last project was a Lotus 7 with a 13B, and after autoxing it for two years I started to think about doing the same thing with the newly acquired Cobra with a bb Ford sitting under the hood. The 7 has almost 50/50 balance and weighs in at 1300 lbs, The Cobra with a 460 that I already had, would be very heavy in the front and be around 2300lbs. By using the 20b I estimated that the car would be about 1600 lbs with close to 50/50 balance. The 460 was to be around 450 hp, 20B n/a I'll be happy with anything over 300hp. Anyway here are a few pics of the car as it is right now, and the 20B as it is:

speedjunkie
10-22-2011, 07:18 AM
Mmmm, this is going to be a nice project lol. Can't wait to see it finished...I like progress pics too though haha.

RotorDad
10-22-2011, 01:27 PM
Well you have an interesting project ahead of you, good luck man.

Trout2
10-22-2011, 01:34 PM
Love it, I've wanted to do this for years. Especially to dig at the piston lovers who tell us how closed minded we are to their molestations of Rx-7's with V8 conversions.

Jack

65pb736
10-22-2011, 08:38 PM
Touche'!!!!

speedjunkie
10-22-2011, 08:58 PM
That's another reason I love this project. If I had the money, I'd also do an S2000/13B-REW, and a Datsun 240Z/20B.

N.RotaryTech
10-23-2011, 06:09 AM
That 2c0Bra is gonna be sweet. lol
^That would make a cool license plate.

Anyway GL on the build.
Looking forward to the fished product.

Ian
10-23-2011, 04:04 PM
Sweet. Subscribed. Interesting build..

65pb736
10-23-2011, 04:38 PM
Here is what I kinda invision the end result looking like. With the exception of the paint scheme.

Tuck

diabolical1
10-24-2011, 01:08 PM
i can't say this is something i've ever thought of, but it does sounds QUITE interesting. also, you're right when you say it makes sense. as a fan of the Cobra, i would go with the archaic 429 Ford, but i probably could be coaxed into something more modern. either way, you have a great project on your hands and i'm excited.

Force13b
10-24-2011, 01:12 PM
Very cool and unique. I'm sure you'll get a lot of hate from the muscle heads but your car not theirs. Love it.

65pb736
10-24-2011, 09:05 PM
Hey thanks for all the positive response everyone. Its kinda 50/50 amongst my freinds on the rotary vs bb Ford on this one. On that note I haven't started a build log on the Cobra forum yet, I may have to chose my words carefully and try to exercise some restraint on my preference for the rotary engine for this project. Of course the success of the 20b powered RX8's limited to 8500 rpm for the Rolex Series and Continetal Tire Series kinda speaks for itself.

RX-Heven
11-07-2011, 05:15 PM
Awesome project. I too almost went this route but decided on the SL-C instead.

speedjunkie
11-08-2011, 05:25 AM
Just don't tell the Cobra forum what you're putting in there until the project is complete...all you'll hear if you do is complaining or trying to find reasons why it won't work, etc. "Surprise!" lol

65pb736
11-17-2011, 09:55 PM
Well a little update, got the high compression rotors on the way. It also looks like I am finally going to have time to finish the garage this weekend. That means that I can bring the rest of the car over and get started on it. The engine is at RX7 World in Rock Hill, SC, Ernst did a great job on the 13b in the Lotus 7 and I don't expect anything less from him on the 20B. Logan at Defined Autoworks is doing the intake manifold for the triple Webers, ignition right now is going to be Electromotive XDI2. After seeing the 20B and then looking in the engine bay of the Cobra the 20B is going to look tiny in there versus shoe horning a big block ford into it, That will be a big diffrence from doing the Lotus 7 with the 13B, which fit very well but was still a little tight. Hopefully all the engine rebuilding and intake will be ready by the first of the year, sooo here we go!

silverfdturbo6port
11-20-2011, 11:34 PM
i always thought this would be cool as well as a bugeye sprite.
http://www.youtube.com/watch?v=jtOLwF2J9b8&feature=fvsr

speedjunkie
11-21-2011, 02:14 AM
Holy crap that thing is loud LOL. It looks like it's smiling too lol, I bet it would be fun. That's awesome.

65pb736
11-21-2011, 10:22 PM
Thats pretty cool!!! I have a freind in Charleston, SC that has a Triumph Spitfire with a 13b in it, its known locally as the Trazda Abomination. Even though its not a 20b its still pretty cool. That gives me an idea, how about a 4 rotor in a Lotus 7?:smilielol5:

vincentrx7
12-10-2011, 01:59 PM
What would be awesome is to have the 20b N/A sound like Logan's (Defined Autoworks)car. The Cobra alone turns heads but with the sound of Logan's 20b, people would be wetting their pants.

65pb736
12-11-2011, 08:00 PM
Hey Vince! Yeah! That would be cool alright. I would love for it to sound like Logans, but I think that engine is a PP. I did'nt have the budget to do PP. I will have to find out from Logan what he is using for exhaust components. On that subject, if anyone has any suggestions on mufflers ect, please chime in. I used racing beats presilencer and muffler on my Lotus 7 and I have been pleased with the way it sounds. I would also be intrested in what anybody has used for a radiator and oil coolers. I have a set of original 20b oil coolers and was thinking about using them with maybe the addition of electric fans. One thing that I do have the luxury of, is a huge engine bay that was designed for a BB V8. I think that the 20b is going to look tiny in the engine bay. Anyway let the pant wetting begin!

65pb736
03-07-2012, 11:38 PM
Well its been awhile. But the Cobra is finally in the garage. I heard from Ernst at Rx-7 World today and he almost has the engine finished. I need to touch base with Logan to see where they are with the intake manifold. I have a fair amount of grunt work to do as the chassis has some surface rust from sitting since 1992. LOL So if anyone knows of a good product to coat the chassis with let me know.

Tuck

djmtsu
03-08-2012, 07:59 AM
POR-15 for the chassis.

Also, get this thing running by April 19th and bring it to Deals Gap Rotary Rally.

DO IT!!!

just startn
03-08-2012, 11:11 AM
Well its been awhile. But the Cobra is finally in the garage. I heard from Ernst at Rx-7 World today and he almost has the engine finished. I need to touch base with Logan to see where they are with the intake manifold. I have a fair amount of grunt work to do as the chassis has some surface rust from sitting since 1992. LOL So if anyone knows of a good product to coat the chassis with let me know.

Tuck

You looking for a "quicky" coat or are you taking your time and want something thats going to last for a long time?

65pb736
03-08-2012, 09:44 PM
There is no way that the Cobra would be ready by April, I do however have a 13b powered Lotus Seven that would be a blast on the Dragon. As far as the chassis coating is concerned I would like to have to do this only once and I am not in any hurry.

djmtsu
03-09-2012, 07:53 AM
Either one, really!

Either way, I am interested in this project.

lilring
03-09-2012, 07:21 PM
I have always wanted to do this!

65pb736
03-12-2012, 11:43 PM
Here's a few pics of the chassis and body in the new garage.

RX-7FD3S
04-12-2012, 07:52 AM
this is going to be sweeeeet :D what kind of porting are you going to do to the 20b?
considered PP ?

Oyvindjs
04-12-2012, 10:43 AM
looks like an awesome project! Keep up the good work :D

Mr N4SA
04-24-2012, 08:23 AM
this is very interesting.

the other day, I search youtube for a conversion like this, but I wasn't successful in my search.........my thought was: a conversion like this would really urinate off a V8 guy.......I got my eyes peeled on this.

The way the lotus looks, I am sure this will be a awesome piece of artwork.

All the best, and may you be successful in your quest

GySgtFrank
04-27-2012, 04:48 PM
Ohhh to see the faces of those holier than thou concours guys!

65pb736
07-11-2012, 11:09 PM
I just got a picture of my 20b from Ernst at RX-7 World. It is now bridgeported and painted. He says that the final assembly should be next week.:patriot:

Mr N4SA
01-25-2013, 08:04 AM
any progress on this project?

RX200013B
01-28-2013, 03:37 PM
I just got a picture of my 20b from Ernst at RX-7 World. It is now bridgeported and painted. He says that the final assembly should be next week.:patriot:


Someone put yer engine together wrong! :)

mattallac
01-28-2013, 10:49 PM
ya , the blue center plates need to be swapped around

GtoRx7
02-02-2013, 12:47 AM
Hey, we have the manifold completed finally! I have the build pics on facebook, have a few more to upload of it fully welded together. Sorry for the long wait Tuck!

Look up Defined Autoworks on facebook, pics are on our main wall.

65pb736
02-19-2013, 09:13 PM
Here are some of the pics!

Tuck

65pb736
02-26-2013, 09:04 AM
And Then There's this.:coolgleamA:

speedjunkie
03-01-2013, 02:16 AM
^Congrats!

65pb736
05-29-2013, 08:47 PM
A little update: The new intake manifold has finally arrived along with the electromotive ignition system. Thanks to Logan at Defined Autoworks for the new intake and ignition system. Ernst at Rx-7 World has the engine finished and is also supplying a fresh rebuild on a turbo II tranny. As soon as Ernst is finished I will go pick up the engine, tranny and ignition bring it all home and really get rolling on this project. So stay tuned. :coolgleamA:

65pb736
08-06-2013, 08:41 PM
Here are a few new pics:

65pb736
08-19-2013, 02:48 PM
Ok, The chassis is now painted. It had a little surface rust from sitting for 21 years. Cleaned it all up and put on a coat of POR-15 and then a coat of black Rustoleum. Here's a few pic's:

jensenator
06-19-2014, 08:54 AM
Thats pretty cool!!! I have a freind in Charleston, SC that has a Triumph Spitfire with a 13b in it, its known locally as the Trazda Abomination. Even though its not a 20b its still pretty cool. That gives me an idea, how about a 4 rotor in a Lotus 7?:smilielol5:

That would be me. The Trazda was sold to a good friend, it's still in Chucktown. It's a 12A motor BTW. I wound up stuffing a 13BT in a Jensen Healey and am currently doing another 13BT in a Triumph GT6 for a good friend of mine. I can't wait to see your 20Bra run!