Jess's 91 BRG LS6 Build Thread

nice update, diggin the guage panel, i think it looks pretty cool... maybe my memory is terrible but the finish on the purple wheels looks like you redid them... if you didnt redo them, they still look fantastic and i LOVE that color

the DD miata teeth cracks me up, haha
 
Boom! Big ass update WITH pics! Nice, Jess. Glad to hear it's coming along and hopefully you've got the fire in your pants to get it wrapped up and driving it.
 
The car was sitting on flat black 15x9s before, I had the 15x10s painted purple last year lol.

Little kids LOVE the teeth!

I know how ADD I am with other threads, if someone updates with a wall of text and no pics I won't get through the first paragraph!

For sure, Evan. Hopefully I can get it going by this weekend.
 
Small updates.

Got a new (used) multifunction switch after determining the stalk switch was bad on my old one (wtf).

Mounted a coolant overflow and bought some distilled water/water wetter which will be going in soon.

D282F5CA-8DD6-4661-9149-DF5D2B3982B0-4816-00000211B11CDD65.jpg


Wired up the water pump finally. Fans are also wired up. Wondering how to put a switch on at least one of the fans so I can turn it on whenever I want, but still retain the ECU kicking them on at the right temp.
 
Last edited:
Wire a switch in parallel to the fan control relay. Like the picture below. This could be done using the power lines to/from the fan, or the relay control wires. One switch will be your manual switch, and the other will be the relay or ECU.

circuit_2.gif


Make sense?
 
That gage panel IS neat. Can you program the four aux gages or are they stuck that way? I take it you've fabricated some kind of wheel speed sensor? I thought all Miatas were similar to RX7's in that they had mechanical speedometers. Somewhere down the road I'd like to do a custom gage panel myself.

Why do you think you need to have the fans on a switch as well as being connected to the ECU? Some kind of failsafe?
 
I really don't remember anything relating to wiring that I learned in high school. :/ and I suck at wiring to boot... So... It doesn't make sense lol. I drew a pic showing what I'm working with. I *think* I could somehow splice a switch in between the 87A terminal and the hot wire going to the fan but I'm not sure if that will even work. I don't know. I am wiring illiterate.

071E7C83-5542-434B-8823-6D6BE1E16AC8-2390-000000F8BB9A519F.jpg



Magnum, what you see is what you get. I've yet to figure out the fuel level, it still shows 00 with some gas in the tank. Usually on v8 builds you see the NA guys wire up a digital speedo. The only other option I know of is the little convert box from FM. On my spear tech harness there was a "speedo" cable coming from the ECU. I assume that's what I was supposed to hook up to the speed wire on the gauges. We will find out, lol. I used a mustang cobra speed sensor on the T56 due to its low profile.
 
Run a wire from 86, to a switch, and then to ground. This will only pass a small amount of current through the wire so you can use a smaller wire and a smaller switch.

If you go fan+ to 30 through a switch you'll need a switch and wiring rated for 30A or more. You will slightly decrease fan performance form the added wire and will have to deal with bigger wire, a bigger switch, etc.

Edit: I assume this won't do anything to screw up the ECU. It may be worth using a "single pole, double throw" switch to isloate the ECU when it's being overridden.

SPDT_sw.png


Where 86 is connected to "com"
L1 is connected to your ECU
L2 is connected to ground

This lets you switch between "always on" and "ecu controlled"
 
Last edited:
Well I've been working on:

-Fitting the projectors into the foglight holes
-Finally torqued all of the suspension/drivetrain bolts and marked them this time (I could never remember which I did before as I assembled the car)
-Put the rear sway bar and new steering rack boots on (Autozone universals work perfect)

But in addition to that I did this:



After figuring out something in the tune was off (DTC wasn't on), and that I had unplugged the fuel pump... it started up. Being the idiot I am I decided to let it warm up to operating temp... and wait for the fans to make sure they would kick on when they should. They did, but they didn't bring the temps down. They hovered around 203-205 (fan 1 kicks on at 195 and fan 2 at 197, both kick off at 190). I figured out why later......... I totally forgot to take the piece of cardboard out of the front of the radiator that I was using to shield it while I worked on the car. So really, no air was going through the radiator at all, the car wasn't moving, and the LS didn't over heat lol. Win! It still needs burped, also.



If anyone has any ideas on the digital tach... it shows only in increments of 100, and is approx 200 rpm off. It shows 700 and the laptop shows 962rpms at warm idle. The wire going to the tach input on the gauges comes directly off the wiring harness Speartech sent me (which I assume is coming from the ECU). Yes, the tach on the gauges come preset for a V8.

Any thoughts?

Excited the car started and nothing blew up, got crunched, or caught on fire.

great_success_brandlive.png
 
Last edited:
well these videos just made me smile haha, hearing that sound coming from a miata is funny and silly and badass all at the same time haha

im no wiz with the electrical stuff but you would think there has to be a way to tweak the electronic tach to match what you are seeing on the computer
 
I agree with Levi that sound from a Miata is crazy. Haha. I'm looking forward to seeing this thing in action.
 
Possible signal interference? Is the tach taking engine speed from the ECU or directly from the coils?
 
Tach is showing ~700... laptop reads 962....

962*6/8 = 721

I something may be setup for a v6, not a v8. I would check any spots were that setting could be made on the digital dash.
 
Possible signal interference? Is the tach taking engine speed from the ECU or directly from the coils?
From the ECU, I have no idea how to take it off the coil on plug setup.

Tach is showing ~700... laptop reads 962....

962*6/8 = 721

I something may be setup for a v6, not a v8. I would check any spots were that setting could be made on the digital dash.
Hmmmmmmmmmmmm. I'll double check. I know when I got the gauges they were set for a V8, unless something got bumped when I was putting it in the temporary gauge holder ma jigger...... Still would love to know why it's only showing 100 increments, though!

Thanks for the comments guys :) SOON!
 
There could also be a setting on the latop that's set wrong and the dash is wrong, but obviously I don't know your particular setup and am only speculating.

It's certainly an odd problem. If you rev more (can you?) that might be instructive.
 
I keep forgetting to check what the gauges are set on.

Oh well. I'll remember eventually lol

Still waiting on the exhaust to be coated.............. the shop said it's been so humid that the headers they've been coating have been blistering and they were going to wait for a drop in humidity to do my exhaust.

So while I wait I started working on my headlight solution: Morimoto Mini H1's in the foglight holes. Before anyone says it--YES I KNOW THEY ARE ILLEGAL DUE TO HEIGHT. I will have LED running lights up top, also.

I learned that the black PVC melts, so I substituted aluminum. Hopefully it will act as a heat sink somewhat.















Nothing is finished or painted yet. I know PVC is kind of janky but I can't think of anything else cheap that's doable and easy to work with.

It will all get sealed and I grabbed some 90* rubber angle vents off some old Miata front turn signals that will get fitted to the top. I'm still working on the adjustability. The two brass screws are attached to two angled pieces of PVC so I can slide them to adjust in all directions a bit.

Any comments/suggestions welcome.
 
If the black PVC melted (I assume where the aluminum is now) then the white PVC has a good chance of melting. I don't see a way that the aluminum is going to carry heat away from the plastic.

Maybe I am missing something?
 
Back