Circuit Race Car Setup
Last week began by taking the car down to Beaurepaires in Wodonga. The guys there do a great job with track specific wheel alignments which the 180SX desperately needed.
Once on the hoist they set to work and tweaked each adjustable arm that I put on there (without any careful measuring) and made sure the wheels were pointing straight again.
Unfortunately, I didn’t get a chance to test the way the car drove afterwards as the ECU is still on just a base map. But the difference in the settings from the alignment print outs are quite apparent.
There is still a healthy amount of camber dialed in which should help it grip well in the corners as well as some extra front caster to ensure responsive steering.
A few days later we then pulled up at Websters Dyno & Performance in Wodonga to begin tuning the Vi-PEC V44 ECU that came installed in the car.
Prior to this I completed a full service on the engine including fitting a new water pump, thermostat and an aluminum radiator. I upgraded the clutch fan to a GK Tech unit and retained the factory shroud as this set up seems to provide the best cooling on track.
It received new spark plugs with a colder heat range as well as fresh oil and coolant. The stage was set to hopefully make some decent power!
Once it was strapped on the dyno Matt began working his magic behind the laptop (which took the rest of the day).
Taking it from the crude base map that barely allowed it to start and run to performing like a healthy SR20DET should.
Take a look at the video below to see how it performed:
I was over the moon with that amount of power from an unopened engine!
It is also running a fairly conservative amount of boost that should ensure a good amount of reliability from the motor.
So with the car back home, now running as good as it looks and tracking straight too — It was time to make some final checks before loading it up for its first outing at Winton!
But of course it was never going to be that simple…
Just as the light started to disappear I fired it up ready to load it on to the trailer. But for some reason it was idling erratically and backfiring as I applied light amounts of throttle.
This was weird, I hadn’t really touched anything in the engine bay since it came back from the tuners.
Still, I checked for vacuum leaks and made sure the earths were good to rule out the basics that might be causing the misfire.
No luck, it still had a constant misfire that seemed to go away once more throttle was applied but it was still running very rough and not filling me with much confidence for the next days racing.
I managed to get in touch with Matt from Websters Dyno & Performance on a Saturday at 6pm and explained what was happening. He was straight over with his laptop and spent the best part of two hours diagnosing the issue.
It was now dark and the car was half on and off the trailer so there wasn’t a whole lot we could do beyond playing with the ECU and checking the spark plugs and injectors (which were fine).
The misfire seemed to get better when he added 20% extra fuel to the entire map, but we decided this was just masking an underlying problem and the safer option would be to remedy the fuel flow issue rather than change the map to fix it for race day.
The last thing I wanted to do was damage an otherwise healthy motor by pushing my luck and having it run lean at high rpm — So I decided to give Winton a miss and debut the car another day.
A very disappointing end to an otherwise eventful week, but the upside is I have a new fuel pump sitting on the shelf that I have been meaning to put in it anyway and once each cylinder is getting the correct amount of fuel again it should be back to running spot on.
A big thank you to Matt & the team at Websters Dyno & Performance, their service really has been outstanding.
That’s all for now, hopefully the next update will be some action shots from the track!
Status update:
So after missing out on the track day due to a last minute fueling issue, I decided to grab some new materials and have a go at fixing it.
I thought I’d begin with the easy stuff. I bought 4 new spark plugs just in case the old ones may have had a contributing factor and installed them.
Now even though the fuel filter was replaced with a brand new unit the day before the car hit the dyno – I thought it would be wise to replace it yet again just in case.
I then started the car up so that I could pull the fuel pump fuse to relieve the fuel pressure from the system before I began replacing the pump.
But to my surprise it started beautifully! No stuttering, no misfiring, it revved and ran perfectly.
It makes sense really. The car has been sitting for a few years now and although I filled the tank with fresh 98 there would still be enough dirt and grime at the bottom of the tank to clog up a brand new fuel filter.
I wish I had thought of it Saturday night, but I guess it’s easy to overlook the simplest of things sometimes.
The good news is it’s fixed. Bring on the next event!
Interested in following the build?
