1989 GTUs 20B N/A Build Thread
Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
I can't wait to see Logan and Peter's work. Those two have some real talent...
Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
I did hear on here somewhere an orange 2nd gen 20B N/A PP on a race track. OMG...I get dizzy thinking that in about 4 months I am going to have something like that here at home.

As far as specs, I guess you mean in general....Also I may be off on some of this stuff. Logan can correct me.
Exhaust:
Custom header, 3.5" coming off of the header, going to a Borla XR-1 mid-resonator. Then there will be a valve that gets a signal from the computer. It will open and close depending on throttle or rpm(not sure). That valve will direct exhaust to one or both mufflers in back. One side of the Y-pipe will be a 2.5" pipe while the other will be a 3.5" pipe. Both XR-1's in back will have a 3.5 or 4" exit. There will be a manual override so that I can have both open when I want. This is mainly for keeping it quiet around town.
ECU: TEC3R
Radiator and Oil Cooler:
Logan has sourced one of each from a NASCAR team. The oil cooler looks like a thin radiator. I don't see any cooling issues here. There will be duct work directing air flow.
Engine:
S5 N/A rotors balanced. I think we are using stock 2mm apex seals. Then there is going to be the semi-pport. So that means six ITBs. Logan has something special up his sleeve on the air intake going to the ITBs. I think I will keep that under wraps until that gets further down the road.
You probably want more particulars that I just don't have right now. I think I have already mention just about everything already at some point. I really have been pretty hands off about the whole engine build. Logan gives me a general idea what he wants to do and basically I just say go for it.
It is funny...I have been so **** about everything on this car so far. I mean really insisting everything be done a certain way. Or doing the work myself a certain way.. But with Logan, I have just basically given some parameters and said go for it.
Update with pics :)
Finally getting a chance to post up some progress pics. Keep in mind that this is a dummy engine. Still waiting for some parts before assembly. We finished up the custom ignition mounts, and built the ignition wires (color coded for leading and trailing).



Also finalized the 20b conversion mounts for FC's. This set for Chris were the prototypes. All TIG welded and basically indestructible. I always disliked the mounts offered by other companies, and the lack of triangulation. So this solved those issues.




And the of course the 20b header! So many hours went into this design. I will post all the details of it in our vendor section. The first two pics is sitting next to its twin, which is going to singapore for a n/a 3 rotor FD.







Also finalized the 20b conversion mounts for FC's. This set for Chris were the prototypes. All TIG welded and basically indestructible. I always disliked the mounts offered by other companies, and the lack of triangulation. So this solved those issues.




And the of course the 20b header! So many hours went into this design. I will post all the details of it in our vendor section. The first two pics is sitting next to its twin, which is going to singapore for a n/a 3 rotor FD.




Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
Wow, that header is almost trippy. Awesome work Logan. 
Hey Gordon, did you notice how much room is between the header and the frame rail? You were wondering earlier about the width of the engine bay...
Is it very much wider than the FD? I can't really tell in your pictures.

Hey Gordon, did you notice how much room is between the header and the frame rail? You were wondering earlier about the width of the engine bay...
Is it very much wider than the FD? I can't really tell in your pictures.
Looking great! I got the chance to see the car in person and I must say it is SUPER clean. You guys have quite a few hours of welding ahead of you on those headers though; that new welder will definitely be broken in after those.
what's the math behind the length? Is there a Burns collector there?
Gordon
Gordon
And thanks! The math involved is tricky, and RotaryGod spent a great deal of time trying to get a formula posted of how to figure it out. He still has not perfected it, with some holes present, but its still one of the closest you will find. I found the length that worked best simply with countless hours of dyno testing on the test mule (aka my daily driver). You can see some details in the n/a performance section under "make that 230rwhp streetport 13bre". I tried almost all header lengths, convergence angles, and collector sizes. These headers are biased off my old design on my personal 3 rotor, but with MANY improvement made, and previous errors corrected. I am excited to see the gains on Christopher's car. After using a SPD collector on my old FD, we were impressed with them and continue using them. They are the same as Burns, just a tad less pricey. Wow, that header is almost trippy. Awesome work Logan. 
Hey Gordon, did you notice how much room is between the header and the frame rail? You were wondering earlier about the width of the engine bay...
Is it very much wider than the FD? I can't really tell in your pictures.

Hey Gordon, did you notice how much room is between the header and the frame rail? You were wondering earlier about the width of the engine bay...
Is it very much wider than the FD? I can't really tell in your pictures.
Thanks!
The R+D is finished on the header, and that is what the production version looks like. It works on FD and FC, Right/ Left hand drive. We can build one or more at any time somebody wants it. A group buy would be interesting. If we could get a list of 4 + people I would consider doing a GB.
The R+D is finished on the header, and that is what the production version looks like. It works on FD and FC, Right/ Left hand drive. We can build one or more at any time somebody wants it. A group buy would be interesting. If we could get a list of 4 + people I would consider doing a GB.
Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
Logan just got my rotors back from CLR. Ha, it only took over a year. Still waiting on the housing to be returned to Defined.
We hope to have the engine together this next month. It will go together first with the stock intake and closed PPs. At that point I will make the 12 hour trip to Ohio. I will get the car and drive for three days to rack up around 1000 miles. Then leave it at Defined until they get the new intake and ITBs happening.
When I pick it up this fall I want the tune to be glitch free and ready to roll.
So, more waiting but that is ok....It gives me more time to pay for it.
I did get a new Nardi Deep Corn 350mm steering wheel with Snap Off (Teqnik) quick release. I also just bought new Defi control box and 60mm, imperial water temp and oil temp gauges.
Next big purchase will be Alcon front and rear brakes...
We hope to have the engine together this next month. It will go together first with the stock intake and closed PPs. At that point I will make the 12 hour trip to Ohio. I will get the car and drive for three days to rack up around 1000 miles. Then leave it at Defined until they get the new intake and ITBs happening.
When I pick it up this fall I want the tune to be glitch free and ready to roll.
So, more waiting but that is ok....It gives me more time to pay for it.

I did get a new Nardi Deep Corn 350mm steering wheel with Snap Off (Teqnik) quick release. I also just bought new Defi control box and 60mm, imperial water temp and oil temp gauges.
Next big purchase will be Alcon front and rear brakes...
Logan just got my rotors back from CLR. Ha, it only took over a year. Still waiting on the housing to be returned to Defined.
We hope to have the engine together this next month. It will go together first with the stock intake and closed PPs. At that point I will make the 12 hour trip to Ohio. I will get the car and drive for three days to rack up around 1000 miles. Then leave it at Defined until they get the new intake and ITBs happening.
When I pick it up this fall I want the tune to be glitch free and ready to roll.
So, more waiting but that is ok....It gives me more time to pay for it.
I did get a new Nardi Deep Corn 350mm steering wheel with Snap Off (Teqnik) quick release. I also just bought new Defi control box and 60mm, imperial water temp and oil temp gauges.
Next big purchase will be Alcon front and rear brakes...
We hope to have the engine together this next month. It will go together first with the stock intake and closed PPs. At that point I will make the 12 hour trip to Ohio. I will get the car and drive for three days to rack up around 1000 miles. Then leave it at Defined until they get the new intake and ITBs happening.
When I pick it up this fall I want the tune to be glitch free and ready to roll.
So, more waiting but that is ok....It gives me more time to pay for it.

I did get a new Nardi Deep Corn 350mm steering wheel with Snap Off (Teqnik) quick release. I also just bought new Defi control box and 60mm, imperial water temp and oil temp gauges.
Next big purchase will be Alcon front and rear brakes...
Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
https://www.rx7club.com/20b-forum-95/defined-auto-646rwhp-20b-video-861448/
I still think about turbos but I am good with what we are doing.
I think some progress will be getting going soon. We have some cool ideas for a custom f/r big brake kit. I will wait and unveil that when we are done. New wheels and tires are just weeks away I think. But I think the finish date is moving into next year. All good with me.. I know it is going to be worth the wait.
Thanks again, C.
Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
No, no....not going to change anything. I just get a little thoughtful about the idea of 500 to 600 hp. I think my car will be a much more balanced platform for fun with the current setup.
Car should be amazing.. cant wait to see the finished setup. All these N/A 20Bs are making me anxious to get mine rolling a little faster. For some reason, I have no interest in a turbo 20B.
Thread Starter
Joined: Jun 2006
Posts: 505
Likes: 8
From: Fayetteville Arkansas
There isn't going to be a hood clearance issue.
Everything is still moving...slowly but still moving. I think Logan will have it running in the next couple of months. Basically the winter has been the issue I think more than anything.
This thing is about 90% paid for.
Don't think that this is another project that ran out of money.
I will update when there is something to update.
Everything is still moving...slowly but still moving. I think Logan will have it running in the next couple of months. Basically the winter has been the issue I think more than anything.
This thing is about 90% paid for.
Don't think that this is another project that ran out of money. I will update when there is something to update.







