I am considering putting a 20B in a Cobra. I have some concerns about where to source some parts to accomplish my goals. It would be much appreciated if some of you could lead me in the right direction. Has anyone set up a 20B with webbers and a distributer? I think that I have the intake part worked out. I read on this forum that there used to be a modified distributer with a special cap from Racing Beat. I have searched their website and not had any luck yet. Any help would be much appreciated.



Tuck

Well, I guess no one has done this before, so I guess that I will do this the old fashioned way and answer my own questions. I JUST Purchased a 20b today and it is supposed to be delivered by the end of the week. Sooo I guess we will see what happens. The fun begins!



Tuck

yes, RB (at least, at one point) did produce the distributor cap. you said you didn't find it on their site, but did you try calling them directly? even if it's no longer available, you might be able to get some technical assistance. they're usually pretty good about things like that.

Hey Diiabolical! Thanks for the response. I will call RB at my first oppurtunity. I think that I saw that maybe Rotary Shack my have them as well. My 20b has arrived and has good compression and appears in great shape. So now the fun begins.



Thanks,



Tuck

As far as the intake manifold you should be able to make your own if you can't find one. I'd use 1" steel plates plasma cut to shap to match the block and the bottom of the carbs and use mandrell bent exhaust tubing to join them. As long as you aren't putting boost on the tubing I'd think it will hold. For the tubing diameter I'd get as close as I could to the same square area of the ports. If not exact then go to the larger size closest.

With a little heat and hammer you could probably make the tubing match the shape of the ports, or at least fairly closely lol

Ok, I have the intake and carbs worked out. Does anyone have any recomendations on what would be a good standalone ignition system for a carb setup utilizing the stock CAS. I have the stock coils but probally need to look at something else that will be readily available. I am in the process of rebuilding the engine and using high compression rotors. Carbs will be triple weber dcoe 40 or 45's, and a custom exhaust header. I am not looking for huge horsepower, but good power, reliability and longeivity.



Tuck

Do you have a specific system in mind? I may be able to help you but, as yours is very custom, It will be more based on what you're wanting to go with.



Most 20b will do the Motec or Haltech route. I will likely be using Haltech.

Hey Leetfade! No I really don't have any system in mind yet. My other car has a 13b with webbers and a distributer. Keeping it simple has worked for me so far with it, however for the 20b project I thought that I would explore a little modern tech at least for the ignition. I have looked through most of the 20b threads and most of them are so old that the pics are no longer available, the links don't work and the systems have all changed. I would like to use the stock cas, but I am open to anything.



Tuck

Defined Autoworks is a good company to touch base with. They are who I'm starting to bounce ideas off of as their 435 whp N/A 20b is something else.... Thing shook me when he revved it.. LoL. I believe they are using a MOTEC (think that's what I saw).

Wow!! 435 HP na!! that would be great, I was only looking for anything over about 300 HP. Luckily I am only going to be trying to push about 1600LB car so I don't need big HP. I went to the motec website and looked around, I think that their new entry level M84 would do a fine job but does alot more than what I am looking for.

I wonder if it is possible to run a 20b with some MSD boxes? I was thinking of calling them to see what they have to say, if for no other reason than to see if they even have a clue what a 20b is. I have run into this with all but one intake manifold maker, the rest of them had never even heard of a 20b, but they all made intakes for 13b's.



Tuck

Yep, called MSD today and just as I thought, they have never even heard of a Mazda 20b or a Cosmo. Maybe I just need to stick to my original plan using a distributer and just figure out how to do a direct fire ignition like I have on my 13b. Nothing is echted in stone as of yet, so I will keep looking.



Tuck

Well, just let me know. If you don't already have a connection, I can probably help you out on some of the parts and prices.



After seeing / hearing the NA 20b from DA, I'm heavily leaning towards that direction. I don't plan on doing the full 435 either but somewhere around his first take at 350ish. I think he said he got up to 365 w/o the peripheral porting... Nasty, nasty car...

Hey Justin! Yessir I need all the help that I can get. Now, what are your plans? Are you putting a 20b in that 93 Rx-7? I know that there are some guys that think that I am nuts for not putting on a Big Turbo and Full blown EMS on a 20b. Well, I am skeptical of my own ability to tune a ems from scratch. Besides that I think that when you raise the hood and there are three sidedraft webbers on what I consider a fairly exotic powerplant has certain amount of just plain "cool". Of course three big ole itb's would be pretty cool too. The only 20b other than mine, that I have seen was set up with three itb's. That was GreyGT-C's car this past summer. He also has a Big Ole Turbo under the hood too!



Tuck

I will go back and forth quite a bit, I'm sure. I'm torn between the wow factor of a 7-800 HP dyno queen (keep in mind this is an advertisement car for my business) and a 3-400 hp N/A road monster.



The current plan is an N/A 20b with an ITB box, street port, doing in the mid 300s. I think that will be plenty rowdy for what I'm trying to do and should keep it manageable enough to still AutoX it! We will see though.. The money won't be in until around March.. All my money is tied up into going to SEMA next month right now! Ha!



I don't think I could do the carb route.. It would be interesting to say the least!

Well it looks like you must be in some kind of car business? If so I can understand your delima, showpeice or driver. There should be a happy median in there somewhere that won't break the bank. Like most people I have to stick to some kind of budget as I have two kids still in college, but I am moving along at a comfortable pace. My engine builder has the engine and is working the rebuild with high compression rotors. I am working on the car itself and thats moving along. The last thing to nail down is the ignition. Worst case is distributer, best case ??? Intake and carbs, the company that is making the intake just needs the go ahead to get started, the carbs can be here in a few days. So if things go well I should have a street legal car by next spring. LOL



Tuck

Nice! Slow and steady is the way to do it. Spring is not far away at all!!



Yeah I am the co-owner of Endurance Motorsports. We're just really getting into the rotary world (specialization is Nissan but we have close to 30k parts) so I'm absorbing all I can!! Ha!



After talking with Defined Autoworks and hearing their 20b N/A monster I am heavily leaning towards the N/A build with the older (88-93 I think) rotors for higher compression, upgraded apex seals, street port and the ITB box. I think I'd be quite happy with a 350hp N/A show car that I can take to Auto X and the occasional road course! I'll likely run a Haltech ECU to run it all or a custom PC Win 7 set-up like our 350z part sponsor car.. Thing is nuts!



My business partner is building a full race S13 that is going to be pretty ridiculous and we have some very nice show cars that we partial sponsor so I want the hybrid!! HA! I want a full-race car but I also want something I can drive to shows.. I'll build a trailer queen later down the road. ;-)

Well Justin it looks like we are both on about the page as far as the way we are looking at our builds, with mine just being a little more ole school than yours. I talked with Logan at Defined Autoworks today, he was very helpful. Looks like they are going to make a intake manifold for my project, so it looks like I need to get busy and find 3 webbers to go on it. You know it might be intresting to compare notes along the way and see how the final outcome shakes out in the end.



Tuck

You are definitely going to be a little ahead of schedule on me! I am going to be responsible this bonus season and pay off another large chunk of debt..Ha. I do plan to pick up a motor before too awful long and start wrenching on it but I need to do a few aesthetics to be ready for the show circuit next year as we plan to try and actually have booths / tents at some shows for advertising.



I will likely start a build thread before too long but the 20b is probably still another year out, unfortunately... :-/ I'll keep an eye one what you have going on, though! Always interested to see how it pans out.



If I had Weber I'd be happy to hook you up on a discount but I only have Edelbrock for something like that. I don't have many carb manufacturers...

y not run EFI?

Simplification. I prefer EFI but some still love the carbs!

Y not carbs?



Tuck

You can't answer a question with a question.. Even if it does make sense!! :-)

LOL https://www.nopistons.com/forums/pub...1047683785.gif

Okay! Now back to the important kind of stuff. Does anybody know if there are gauges that are compatible with the original Mazda sending units, or is it a matter of adapting aftermarket sending units to fit the engine, or do you use all mechanical guages with adapters to fit the engine? I did the latter on the 13b in my Lotus 7. Just wondering what everyone else is using.

Well, I bought Elite 10 Series GlowShift gauges and they, mostly, go off the factory sending units. I had to buy a sandwich plate for oil temp / pressure (obviously) but everything else either has inline units or just uses factory.



I am debating on sticking with them or going with something a little less flashy. I like these because they have adjustable threshold warning levels and adjustable colors to fit your interior / scheme, but I do like a really nice and clean look with just enough light for visibility so I'm torn... That, and they were pretty inexpensive since I have a direct account! ;-)



We have a TON of options and it's all about your budget, really.

Yeah I know what you mean, this having to budget really sucks. Its just to bad that we can't do like the Feds and just print some more money as we need it. I was looking at some Auto Meter Cobra gauges but they are right pricey. I have a little time before I have to make a decision on this anyway.

I sell them so I can try to work you a deal when you're ready.

Hey Justin, Thanks , that would be really cool!

No problem. Just let me know which ones you need when you're ready to buy and I will do what I can.



I may be moving up my 20b plans.. But I think I'll do a as-is drop in to drive for a year or two and then start the build.. I'm really considering single turbo again, though. Just to say I had a 700+hp car! Ha.

Yeah Justin I am with you on that. Do you already have the 20b? And If so is everything there to make it run? From what I have been researching there is only one or two people that have gotten them to run with all of the oem stuff mostly due to lack of of technical info because all of the manuals are in japanese. If I had thought that I could get mne to run out of the crate I would have probally just gone with it the way it came. Or maybe I just missed the boat on this one.



Tuck



PS The Auto Meter gauges I was considering are the ones they call the Cobra Collection I think. They are supposed to be somewhat correct to original gauges that came with the cars.

I would try to work with Defined Autoworks since they seem to be the rotary gurus in my area. They definitely know their crap and I already got a quote of them supplying the engine, refreshing and installing it but I want to try to do a lot of it myself.



We do have the cobra gauges (Cobra Series) so that's no problem, we can just work on price whenever you're ready. I hate to quote before because you never know when they're going to change prices on me (I get an email at least once a month with manufacturers changing prices). So just let me know!

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!

NIIICCEE!! Can't wait to see some pics / hear some vids!



Are you going to do shaved bay, wire tuck, etc? If you have that much room you might as well make it super clean! Ha!

Okay I'm not sure what shaved engine bay means but I did shave this morning and I have been called alot of names before but wired Tuck, maybe, maybe not! LOL I'm looking forward to making alot of videos when this thing is together and running, but to get started here are some pics of the car as it is now and my 20b as it was when it arrived:

Are you sticking with red for the outcome color? The rear end looks like a TVR!

Nope, I like the color scheme on my Lotus, navy blue and screaming yellow. I always thought the TVR looked like a cross between a Datsan 240z and a Lotus Elan. I have not ever seen one in person but remember reading about the in the seventies.

We actually had one at a local show called Cars and Coffee. There are some very nice and very rare cars there.. Hell a full restored Packard parked behind my S14 when I had it... I wanted to hide my head in shame!! HA!

Packards! Coool!