Shifti's 20b turbo Fd project.
 

Hello fellow rotor heads,

I have had my 92mod fd since 2003, it started out fairly stock but after the first summer i started building the car with a t78 single turbo big street port, 3mm apex seals, 12,7mm studs and every mod in the book for what was the norm back then.
I started way to hard on absolutely everything so the build took forever.
but in the summer of 2013 the car as finally done.
started to break tho motor in and found out quikly something was wrong, the rear rotor was running over 200 degrees celsius hotter then the other one.
tried to check everything i could think of, compression, ignition, injectors, wiring and so on. got sick and tiered of the car and have just lett it sitt in the garage for two years while my trackday NA Miata got all the love,
but this summer 2015 i finally started to work on the fd again and found out that the engine builder had not done a god job, one of the 3mm apex seals got blowbye when the engine was under load.
It had perfect compression when we tested it, and at idle there was no problem,
But under load the combustion blew over to the next chamber and the exhaust temperature dropped.
so i started to check what parts i could use again in a new engine and the verdict was not good.
so after a good friend of mine came up with a 20b d block i realy could not say no. i have always wanted a 20b and since e85 was pulled from the marked in Norway the decision was not a hard one.

So here are the plans for the swap.

I want to use the stock subframe and not move the steering rack, so i will move the engine back about 13cm (5,11 inches)
the oil pickup will be modified and i will make and custom oil pan.

d-block 20b number:525,
3 new 20b housings with 13b exhaust sleeves, maybe i will swap them for the ones in titanium. (easier to weld on and reshape)
studs.
13b front cover.
Full Function Engineering fd trigger wheel.
triple plate exedy cluch and fly wheel.
custom engine mounts,
oil mod.
water mod.
oil filter relocation.
ceramic apex seals
custom 2 piece billet oil pan.
custom aluminium or chromoly propshaft.
custom hollow (failure steel) drive shafts. (not sure what they are called in english)
1,5 way OS-giken diff.
shorten ppf.
Fd gear box,
exessive short 20b lim.
Remachined 20b uim.
custom remachined 13b-rew throtlebody 50mm primary and 54mm secondaru butterflyes.
custom 3,5 inch elbow.
motec m600 or m800 ecu.
aem coils.
electric water pump.
electric servo pump.
custom billet Alternator bracket.
custom v-mount settup.
Greddy 3 Row Intercooler
3 inch ic tubing from turbo to ic.
3,5 inch ic tubing from ic to elbow.
wiggins clamps,
custom bov.
gt42 or a simular size turbo.
60mm wastegate.
custom header.
4 inch custom exhaust.
custom fuel tank.
Aeromotive Pro Series Fuel Pump.
Aeromotive Pro Series Fuel regulator.

this build will take a while since i'm not filthy rich, and i have customer cars that needs my time while i do this build.
But the plan is to be done in 2017.
Will post pictures of the car and the parts i make as the project is coming along.
I'know there are many here that have done this before, so i would like to hear your thoughts as this build comes along.
And i want to excuse the English, i'm Norwegian so i hope you understand what i'm trying to write. hehe.

here are some pics of the car and the new rotor housings.

the 20b uim in the mill for adapting it for the ported 13b-rew throttle body

Drew up the new flange for 3.5 inch elbow today, then i will water cut it in 15mm aluminum so I have enough material so i can mill the surface after welding.

So i got the flange water cut to day, first I cut it in 2mm to check the fitment, then i was suppose to cut it in 15mm, but i was out of 15mm, so i cut it in 20mm instead.
there will be more milling to get it to the thickness i want it to be in the end, but that's not a problem, at least it vill be stiffer and warp less when i weld it.
Here are some pictures of the fitment with the 2mm test on the throttlebody and the final flange on the Greddy elbow for comparison.
The throttlebody is milled out, and i have made bigger butterflyes. this was done some years ago and i used it on the 13b.

The old dimensions are: Primary 45mm Secondary 2x 50mm the surface area of the 3 old holes with out the butterfly and axle is: 5514,625mm
The new dimensions are: Primary 50mm Secondary 2x 54mm the surface area of the 3 new holes with out the butterfly and axle is: 6540,62mm

In comparison a 90mm throttlebody without the butterfly and axle has a surface are of 6358,5mm

Here are some pictures of the 20b UIM after milling. I welded on more material on the upper and lower side of the intake between the flange and the plenum so i had enough material when the milling of the bigger ports was done.
I also welded up the the channel in the flange because i don't use it when i use the 13b throttlebody.
I also welded up the vacuum ports on the rear end of the plenum, because it will be to close to the firewall.
I think i will make a vacuum box under the intake and run a AN-16 from the plenum to the box and use it for all the vacuum hoses i need.
And for good looks the flange was milled down a bit at the top end so it mated perfectly with the 13b throttlebody.

A Question to you guys running 20b's, are you seeing higher exhaust temps in the center rotor?
Looking at the intake i would believe the center rotor gets more air than the front and rear rotor, since you can look straight in to the runners for the center rotor.

Looking great. I don't think you need AN-16 for the line. I have 1/2" (AN-8) and it seems to have no problems with tune. AN-16 is also pretty darn bulky to plumb around the bay.

As for individual rotor temp, I don't think anyone here has separate exhaust temp sensor dedicated to each runner. I asked about it a few months ago because I had similar concerns. It's definitely something I would be interested in knowing as well

thanks, I have just started to make the parts i know i want to change before have time and space to start getting the 20b in the car.

Good to hear. was just afraid that a small dia hose would cause delays in vacuum and pressure.
I have a lot of extra AN-12, maybe i will use that instead. AN-16 is like you say, very bulky.

Really strange that the high power 20b guys don't have one in each runner, it's a good way to make sure the engine don't have some rotors going leaner than the others.
I am going to use 3 exhaust temp sensors, one on each exhaust runner 5cm from the block, so i can fine tune the fuel delivery for each rotor.

And what will you be using to read these 3 exhaust temp sensors?

You can use a multi-channel pyrometer like this:
Thermocouples Electronics

If your ecu can't logg 3 exhaust temps you can hook up 3 multimeters to 3 exhaust probes when dynoing the car.

I'am going to use the motec ecu for logging all 3 exhaust temps.

Another option:

TC-4: 4 Channel Thermocouple Interface

So i got time to do some more work on my custom elbow. I ordered i short radius 90 degree 3,5 inch bend an started to cut it in both length and width.
And welded it together with some parts i had made to fit the flange.
The reason i do this is to get a true 3,5 inch ic tubing from the ic to the throttle body.
i also wanted a sleeker curve before the throttle body and more length from the curve to the throttle body.
Have some pictures of the parts and the soon to be finished elbow.
I'm not sure yet if i will keep it at 90 degrees or if i will cut it down to 60 or 45 degrees.
I will see how it fits when the engine is in the car, it was allot of welding and making small parts to fit the shape i wanted.
So when i'm finished with grinding down all the welds inside and outside the elbow, i will warm it up in the curing oven at work to stress relief (annealing) out all the tension in the metal after welding, before i mill down the flange to the thiknes i want.

All welds grinded down inside and outside. and ready for milling the flange.

So i finally had time to dismantle the 20b with some help from phillip gardner,
everything looked very god with almost no wear on the side plates. and the rotor housings looked good as well.
So now i will start to clean them, and i have to buy some sodium bicarbonate, so i can soda blast all the parts.

It's finaly time to take out the engine, so i took some pictures of the engine bay with the old 13b setup.
I am going to use the front cover from the 13b on the 20b and the custom Alternator bracket.

Would you consider making one of these to sell? I would be very interested.



Im glad you appreciate good fittings. Most people take them for granted.

thank you, i like to make things as durable as possible, and good fittings is a part of that.
The car will see a lot of track days so i need everything to be as reliability as possible.

"I could, but i don't think you would like the price. hehe.
It's a lot of work, so it would be a lot more expensive then to just buy a casted one from greddy."

I believe that if someone wants truly good parts, then the cost should be an afterthought. I have one already and was planning to cut it up to make it suite my needs.

That's true, i can check out how much it would cost to make one more. Will let you know.