Stock Car Mafia's '78 280z LS2 Build

[MRGierut]

If you re-cut your rear flares, put jackstands under the front to level the car.  I had mine jacked up just in back like your photo, and my flares are rotated toward the rear a little and it looks "off" now that it is on level ground.  All because the car was sitting at a nose-down attitude when I drilled for the mounting bolts.  Longer coilover springs are available on Speedway.com for $55 each.  Just figure out how much you need to raise the car and order longer springs.

What's the best way to check if the car is level, putting a level on the door sill or frame rail?

[Stock Car Mafia]

When my car was on the ground I would measure the frame rails underneath at 4 locations.  If on jack stands, I would say use a level on the frame underneath.  

[Stock Car Mafia]

I'll have a hard time containing myself over the next few weeks but I will have a big update coming in roughly 4 weeks!  I am in the midst of preparing for it but will post up when I have more to speak of   

 

During the Phoenix race today I would sneak out in the garage periodically.  I had a little 3 yr. old helper assisting me in replacing my blinker bulbs.  I was looking to chase down an issue with my blinkers.  Last year I had a small poof of smoke from under the steering column that gave me QUITE a scare.  It turns out the blinker switch shorted out and slightly melted the plastic piece and the power wire.

 

My hazards work but my blinkers don't.  I cleaned up the switch and wire contacts and am able to get right blinkers when you hold it in just the right spot.  I am able to jump the wires and the blinkers work fine, so I know it is due to the blinker mechanism.  I guess I'll leave my under dash and center console tore out until I get it fixed.  Let's hope it doesn't stay that way all year lol

 

I am looking for some guidance on a rear sway bar and rear mount setup like the AZC dog legs.  I didn't find what sway bar fits and where to get it from.  Any advice you guys have would be great!

[BLOZ UP]

I highly recommend a relay kit for the parking/signal lights and the headlights. You can also get LED bulbs that significantly reduce the load through the stock switch--negating the need for a relay for the parking lights.

[Stock Car Mafia]

Right now it has LED bulbs all the way around.  I think that cuts down on the load, however I think the harness and stock switches are just getting to the end of their life.  When I strip the car down next, I will rewire the whole thing and only have the necessities and definitely invest more time in organizing and routing of all circuits.  I want a CLEAN install, not added stuff just piggy backed on the stock harness.    

 

I highly recommend a relay kit for the parking/signal lights and the headlights. You can also get LED bulbs that significantly reduce the load through the stock switch--negating the need for a relay for the parking lights.

 

Right now I have been spending as much time as I can reading on HPTuners and trying to digest that software.  It is definitely a process and takes a focus to comprehend it.  I am confident I will get there instead of depending on tuners.  No fault to those guys, I just feel I could educate myself a little deeper in to this passion!

 

I got the car out this weekend for the first cars and coffee of the year.  My god, this event keeps getting bigger in regards to people and cars.  It was packed this year.  I was fortunate enough this weekend to have a photographer catch the car in action!

 

 

[73z85.0]

It's been a while since I read the whole thread.. Can you re share what hood you are running?

[bramagedained]

Someone caught video as you were leaving that was posted in the C&C facebook group, too.

[MRGierut]

That thing looks pretty damn good rolling down the street. Great pictures!

[Stock Car Mafia]

I will have to look this up.  As I recall, I could never find the manufacturer of this hood, only pictures of it.  I knew it is the one I wanted but they quit making them a long time ago, so I had to buy a used one that I found out of California.  

It's been a while since I read the whole thread.. Can you re share what hood you are running?

 

If you can find that video, send me a PM on here or on Facebook so I can check it out!

Someone caught video as you were leaving that was posted in the C&C facebook group, too.

 

Thanks!  It's been a lot of work to get to this point, but my imagination prevents me from being satisfied  

That thing looks pretty damn good rolling down the street. Great pictures!

[Stock Car Mafia]

So I've been debating for months and keeping my eyes open for used engines and superchargers.  I took the plunge and got a fully forged LS3 416 stroker off of LS1tech.

 

 

It has:  

ARP main studs, head studs, and rod bolts

Callies Compstar crank

Callies Compstar H beam rods

Wiseco -3cc pistons gapped for nitrous/blower

Trickflow 235cc cathedral port heads milled 0.045"

11.98:1 compression ratio

10296 Melling ported high pressure oil pump

BTR 247/255 .624/.624 113+3 cam

Katech timing chain

10% underdrive ATI damper 

 

The motor has the Corvette pulley so I am going to be cutting it close for steering rack clearance.  If it is close, I have a few ideas of eliminating it.  

 

I have had next to no time to even dig in to this project yet but I do have my old LS2 tune file and the tune file from this motor.  I have been trying to read up on HPTuners and trying to get a grasp on it for my own pleasure.  Since I have both tune files, I do believe I can get the car running.  Granted his tune was done in EFI Live, where most refrence tables have inverted axes in comparison to HPT.

[Stock Car Mafia]

I ended up getting a electric water pump off the forums as well.  For some reason the damn motor gets to about 220-230 while sitting in stop and go traffic and I am not ok with that.  

 

 

I think this should do the trick and I don't believe I will have problems at the higher rpm either.  Time will tell.  

[BLOZ UP]

LS motors run hot, IIRC. 220 is not uncommon. Meanwhile my VG33ET struggles to get to 190, even when sitting.

 

So you still want more power? I am tempted to get an LSx (or LQ4) and turbo/twinturbo it. I am trying to find out at what point the aluminum blocks don't like boost, but am finding lots of various opinions.

[Stock Car Mafia]

Mine runs hot but it gets to a point where it will go above 230 if I don't get air moving through the front.  It just makes me feel uncomfortable.  

 

I was looking for more power but room to grow if I go boosted without the fear of bending rods or popping a ringland on a piston.  I'm thinking as long as a motor is forged you are safe up to 900 hp before you'd need 6 bolt style heads.  But I've seen aluminum blocks run to 1000+ so I wouldn't worry.  That power is only needed for AWD cars or strict drag racers.  I would prefer to race a car other than going straight.  

 

At this point it might be a little too much power but it will be fun.  Now just thinking about different tire compounds for traction and possibly changing gearing or tranny ratios.  

 

LS motors run hot, IIRC. 220 is not uncommon. Meanwhile my VG33ET struggles to get to 190, even when sitting.

 

So you still want more power? I am tempted to get an LSx (or LQ4) and turbo/twinturbo it. I am trying to find out at what point the aluminum blocks don't like boost, but am finding lots of various opinions.

[Stock Car Mafia]

In preparation for getting HPTuners today, I spent some time over the weekend installing a bung for the WEGO III wideband AFR sensor I picked up.  It uses a Bosch LSU 4.2 oxygen sensor.    

 

 

The sensor seems pretty nice after reading about it.  The device has the capability if connecting a tach signal and TPS or MAP sensor to datalog.  It has it's own software to run independently which supplies data with USB.  The greatest thing that made this a good option for me is it was cheap and came with a 0-5V output to connect to tuning software.  

 

 

The brown wire (to tach signal) and the green wire (for MAP sensor) are not needed to connect to HPTuners.  The ground wire for the sensor and device are both grounded to HPTuners.  I just need to find a good spot to tap the red power wire to a switched power source.  I am thinking the easiest spot is the pink wire that powers the ECU but I will need to add an inline fuse....

 

I finally stopped being lazy and dropped the exhaust to add the flex pipes.  I found the sweet spot that allowed me to add the O2 bung about 10" downstream from the header collector.  This gave the most room for the sensor to be added.  

 

 

Once I made the cuts, I bolted the mid pipe and mufflers back in to the car with the flex pipes roughly added in.  

 

 

This allowed me to get the exhaust tips EXACTLY in the same spot they were before.  I had Katie look from the back as I got the mid pipe centered to tack it in.  

 

 

Everything went fairly smooth except for running out of welding gas!  I was able to pick that up Monday and finish the job last night.  Before throwing the sensor in the car, I had to do a free air calibration on the sensor to dial it in.  

 

 

 

As you can see, this left a good amount of room for the sensor.

 

 

This worked out perfect and allowed me to zip tie it to the transmission harness up and out of the way.  I fed the wire through the driver side firewall and over the pedals through the center dash.  Sine my radio was removed and sold, I will be making a mounting plate probably there for the device.

 

I wasn't able to finish up the wiring yesterday, as I want to find the best routing for the output signal, usb, and the ground.  If used independently, the ground needs to be mounted to the chassis.  If used with HPTuners, it needs to be connected to the handheld.  So I need to find a good spot i can quickly remove.  Still looking for ideas.  

[Stock Car Mafia]

I am working with a guy to sell all of my stock A/C components from under the hood but also the evaporator under the dash.  Since I still need to figure out, what in the hell is wrong with my oil pressure gauge, I figure this is a good opportunity to remove the remainder of the stuff.  Weight reduction bro!  

[Stock Car Mafia]

Over the last few weeks I was able to sell off my stock tires, all A/C stuff, gas tank, stock hood, mirrors, and some miscellaneous CBR bike parts I had laying around.  It is nice to soften the blow of the new motor.  

 

I still have had little time to spend any time on the car except for driving it to and from work.  We did find a free power wheels jeep for the 4 year old and I ended up buying 2 decent batteries so we could get her juiced up to 24 volts.  She loves having something to drive

 

One concept I've had a tough time wrapping my head around is making sure my wideband O2 sensor is not only calibrated but dialed in to read accurately in HPTuners.  From just the gauge reading alone, I could tell the AFR reads a little high but there was a difference between the gauge and the output signal for the AFR...I read up on a plan to videotape both the gauge, HP Tuners reading and graph them to derive a new slope for the AFR range, and then a voltage offset.  

 

 

The equation that is built in for the WEGO III in HPT is:

 

AFR = (Volts/0.543478261) + 10.3  

 

Based upon my data below I am probably going to use the equation:

 

AFR = (Volts/0.5004) + 9.94

 

I eliminated some data that fell out of speck to come up with this.  I have yet to test it using a user defined math parameter in HPT but I am feeling more confident with this calculation.  I hopped the power wire to input #2 as well so I could see just straight voltage.  

 

I think the next steps I will take to practice more with the HPT scanning software is to swap on the motor the new 102 FAST intake, 102 mm Throttle body, and possibly the new ID850 injectors I got.  I think this would be a good experience before I dive in full scale with the new motor.  

 

After I get the new motor tuned in on 93 octane, I ended up buying a flex fuel sensor that I plan on installing.  I found out the E40 red headed step child computer I have does have functionality for flex fuel and ethanol fueling.  I am excited to learn this aspect as well but also protect the motor from detonation and burn a cleaner fuel.  

 

Other than that, I am taking it one day at a time.  I really hope to accomplish all of this by the middle of July.  

 

[Stock Car Mafia]

I forgot to mention, I had to build a custom tune to get the AFR to scale while I changed the RPM from 1,000 to 4,000.  I had to disable the MAF and a few other things to allow the system to stay in open loop.  From there I set the PE enrichment to range from 1.420 (AFR of 10.35) at 1,000 rpm to 0.918 (AFR of 16.01) at 4,000 rpm.  This allowed me to get the AFR to change from an otherwise static 14.7 in closed loop.