i love your work man and iam happy i found this thread ill def be keeping my eye on this, you mind me sending you some pm's asking some questions ect.

 

Good point... I was wondering what I should do about that fork... I've been trying to decide which way to take my eventual build... NA is muh more satisfying but expensive... and the FI is gona give a better power/weight retio. Oh well, what ever... GREAT build Jeff!

 

It will be street driven. That's the nice thing about a 20B - its torque makes it very streetable. I suppose if I want to do autocross or gymkhana, I could if they allow such a beast.

Since I'm already doing a 20B you might as well do a Renesis and figure out a way to simplify it like I did with the 20B (reduce the spaghetti and extra sensors). Both engines are far too complicated stock, especially the Renesis. As j9fd3s said, the stock RX-8 ECU is fast and programmable, but only the factory can program it. If someone doesn't figure out a way to crack it, just do a standalone and prevent the headaches - especially if you're installing in a 1st gen - keep it simple! Redo the fuel rails for a return style fuel system too!

I'll answer the next three posts together. It'll be NA for now since it is an early engine. When I said #756, I meant #756. There is no A or any other letter. That means weak shaft and castings. That means NA for now. I may go turbo at some point but I need to tear it down to freshen the seals, at which time I'll get to see which shaft I've got. Chances are if it was a factory rebuild it got the better shaft. If so, I could go turbo if I kept the boost low. Of course a low boost 20B can outdo a high boost 13B, and be more streetable and reliable. You gotta like a double whammy. At that time I'll upgrade the tranny, driveshaft, rear end, brakes blah blah blah. For now I'm keeping the tranny and everything after it stock. I know stock stuff works for a while at high power levels if you're not a total retard. And since I'm a total rotard...

I'll just update this thread when I've made progress.

warwickben, as long as you don't flood my inbox with noob questions it shouldn't be a problem.

I don't throw money at a project. Instead I think things through and proceed. It works for me and doesn't cost very much.

And now here's an update. I got the crossmember trimmed and welded back together. It turns out the cuts were a degree or two off. One side had a gap at the top and other had a gap at the bottom. I followed the tabs but maybe they were just a hair off? Oh well. The gap took up the material removed while cutting. The blade was about 1.5mm thick and the gap worked out to around 3mm or so.

 

^Wow, that is one of the originals. If it were a Mazda rebuild, it would have black housings and the number would be ground off. Keep it NA for now and enjoy!

 

Man that thing is looking awesome Jeff!

 

David, all my research into Mazda rebuilds suggests that they only had the numbers ground off, but rarely if never were black. There are a few pictures of black rotor housings and a black manifold floating around, but all the confirmed Mazda rebuilds have been unpainted. Infact the UIM and LIM I picked up a few years ago came off a B series engine that was definitely a Mazda rebuild. It was B410 stamped on side plates only while the rotor housings were ground off.

Latin, you should see the crossmember now. I got it in but ran out of time to hook up the A arms. I'll get 'em hooked up today and take a picture. Then I've gotta work on an '81 S model project for that 12A I pulled. Once the 12A is in the other car I can measure all the angles so the 20B will sit right.

 

wow, definitely makes it interesting. I've just swapped to a 13b egi and would hopefully eventually swap to a 20b or short block tripple NA. But It won't be on petrol, the 13b is on a only propane setup

Will it be an injected setup or carbed ??

Shaun

 

You'll see.

 

I hate suspense...

 

The anticipation...........

Shaun

 

[QUOTE=Jeff20B;7356509]David, all my research into Mazda rebuilds suggests that they only had the numbers ground off, but rarely if never were black. There are a few pictures of black rotor housings and a black manifold floating around, but all the confirmed Mazda rebuilds have been unpainted. Infact the UIM and LIM I picked up a few years ago came off a B series engine that was definitely a Mazda rebuild. It was B410 stamped on side plates only while the rotor housings were ground off.

Interesting. This isn't what I found here or on the Aussie forum. I had a need to learn more about the numbering system a few weeks ago. My research turned up the black rotor housing theory. A few on the Aussie forum (or maybe ot was here) posted pics.

 

I've only seen one set of black rotor housings and they may have been painted by the owner. It was in the white B series Post Falls Mazda truck. It also had a supecharger. All the other 20Bs in pictures or real life have not been painted, and I've been on the look out for 10 years now.

 

This is awfully close to the centerlink isn't it.

Think I'll run into problems?

 

Here ya go, from DMRH and Australia. This is where I got the info on the black rotor housings. These are the warranty work Mazda rebuilt ones:

 

Thanks for that.

I got the 12A in the S model so now I have a guide for tranny tilt and position when I go to install the 20B. Just need to pick up some steel and wait for nice weather.

 

I've been thinking about steel lately. I wonder what would be the best to get? Angle iron? Square tube? Round tube? Please advise.

 

square tube will be heavier, and just as strong as round tube - but much easier to work (weld) with.

 

I have some round tube. It's for natural gas and really thick (1/8" wall) if I remember right. Hmm.

 

no? the center link moves on an arc, and with the wheel straight its as close as it will get to the subframe, when you turn the wheels it will move away....

 

Thankyah Mike!

On to the front motor mount crossmember. Here is a list of parts I think I'll use:

3' natural gas pipe 1" diameter 1/8" wall
two angle irons, 1.5" x 1.5" x about 6" long
reuse the original motor mount pedestals, cut and shaped to fit the pipe
Four long bolts to mount to the frame rails
Four small diameter tubular sleeves welded to the frame rails to add strength and to house the four long bolts (like the stock main crossmember)

First drop 20B onto tranny and check tilt/alignment/tranny tunnel clearance. Check critical clearance between pan and reversed crossmember. Install front mount plate to front cover, rubber motor mounts (I'll get competitions later) and original motor mount pedestals. Test fit angle irons to frame rails and pipe to motor mount pedestals. If it all looks good, lift the engine a little to account for the sag in the motor mounts, and tack/drill everything. Finish welding and throw it back in. Sounds simple enough. I've never done any of this before.