SR20 TUNING

Arghhh! What a day. I diagnosed the problem very early on as a ruptured turbo coolant hose. It had become pinned between the compressor housing and the engine mount and had slowly wore away. It turned out to be insulated rubber hose instead of stainless steel braided hose. I had spare braided water lines that came with the turbo so the job should have been straight forward to replace the hose.

For most of the day it really was. I had the turbo off in a couple of hours. The removable external wastegate pipe was fantastic in the way it cleared up space. I removed the turbo with the manifold and dump pipe still attached which is my favourite method. Another half an hour and I had the new coolant line plumbed and routed.

In only one hour I had everything back on and started up the engine. Oil started squiring out everywhere…

When previously attaching the turbo oil feed to the block, I dropped one of the copper washers from the banjo bolt. I had a container of new spares so used one of those, but for some reason it wouldn’t seal. I pulled off the banjo, swapped the washers around and now the leak moved to the outside of the banjo, following the replacement washer. Again I pulled it off, found the original washer resting on the engine cross member and started to reassemble. I had a lot of trouble getting the thread to start. A few more attempts and the bore in the block was officially threaded.

By now it was 6 pm and I was over it. A $250 trip to Bunnings later, I had a new 90 degree drill, a 31/64″ (12.3 mm) drill bit and a M12x1.25 mm thread repair kit. The danger was of course getting aluminium debris in the oil gallery.

I cut a small square of cloth and used tweezers to jam it in the bore. After this I carefully drilled and tapped the thread, using cotton buds and rags to clean debris regularly. There was a lot of stuffing around trying to get the tools to fit in the available space. The heli-coil looked too long so I used side cutters to trim off a few rings. It went in very easily and smoothly with the supplied tool. Snapping off the tang was difficult because the protective cloth was still at the back of the bore and stopped it from moving. I removed the cloth with tweezers and then wiggled the tang until it snapped.

Next up I started the engine with the oil hose disconnected to blast out any possible remaining debris. A bit messy but worthwhile. With a pounding heart, I reinserted the banjo bolt and it screwed in smoothly, tensioning at the end without the dreaded feel of a damaged thread. The engine started: no leak! Even better, it was still good after a test drive. Crisis averted and the new thread should be stronger than ever in theory.

The product I used from Bunnings is depicted below. It would be as easy as they illustrate if it weren’t for a cramped engine bay and the kit going into an oil gallery that absolutely had to stay clean.

Tomorrow afternoon the plan is to get the half cage bolted in. I’m planning on drag racing this Wednesday night.

Long time between posts! My work has the ability to take over my life, which it has done for the last couple of months.

I still drive the Sileighty once a week or fortnight to work, the last time being three weeks ago. On this drive I noticed a burning smell and some steam upon arrival. Pretty sure the coolant line for the turbo is leaking onto the turbo. The car got a bit hot on the drive home but seems ok and has been still since.

Last night I picked up a nice bolt in half roll cage and sold my old S15 seats. In the next few days I’ll be aiming to to pull off the turbo to fix the leak as well as installing the roll cage.

After that I’m keen to take the car drag racing to improve on the previous time now that the misfire is fixed. Updates to come.

I’m very impatient when I’ve decided to purchase something. With that in mind, it won’t be a surprise to read that I have already bought and installed some new seats.

I found some Bride Gias replicas on genuine Bride s-chassis rails for $800. The condition is pretty good, a bit grubby here and there but no rips. The red colour really stands out against the black and white theme.

The only tricky part was transferring the seat belt clips to the seat frame, which requires the lower seat cushion to be removed. If anything, the seats are a bit tight around my back but overall I feel very snug in the seat. I can always add a bit of padding underneath the velcro section of the backrest to help the situation.

Overall I’m just really excited to have the new seats and can’t wait to track test.

I have just finished another drift day today with Driving Sports. I was free and they were advertising places available so why not? This is exactly what the car is for. The car was faultless. I’m not sure if the new ignition system or tyre wear was to blame but the car seemed quite overpowered. At the start of the day I was spinning frequently and only corrected this once applying very little throttle. I would say that most of the time the engine is off boost.

I’ve started searching for the next mod, most likely some Bride replicas. This was already on the cards but after today my sides are killing again. The S15 seats grip but all the pressure is in one spot. I asked some fellow participants if I could sit in their seats and try them out. After doing this I think I’m going to get fixed back seats this time around. They are lighter and with a decent rail, can be mounted at various angles and heights.

Rails are easy to find for recliners, but the actual seat is more expensive. Rails are harder to find for fixed back, but the chairs are light and cheap. I’ll post up how I go.

Work is back and busy so I haven’t really played with the car until this weekend. I managed to install Yaris 1NZ coil packs and write up a very detailed page on how to do so. I spent many hours reading up on coil pack workings and upgrades before doing this mod. I consider my page to be much more comprehensive than anything else I have come across, so check it out: Ignition Upgrade.

I am really excited by the improvement in performance. The car still doesn’t boost as hard as my old HKS 2510 equipped 180SX, but once the VTC is reinstalled the mid range improvement should be prolific. The current high RPM pulling power is at least as good. I think at least a few tenths will come off at the drag strip, which means the old system was really struggling.

Back to work which means car time will become limited. I’ve had an amazing run so can’t really complain. My wife has strangely told me she would like me to finish off the performance mods on the car so we can then concentrate on saving for renovations. Seems like a trap but I’ll go with it.

She said to make a list so here goes:

New coil packs – The car is steadily developing a misfire. Initially on high boost but now on low. I first wrote about a miss a few months ago, I guess a coilpack is on the way out. The plan is to use something stronger than stock like LS or Yaris. Some wiring will be needed to circumvent the ignitor chip.

VTC gear – I still miss the midrange punch my grey 180 used to have. I know the VTC gear is physically missing. Hopefully it is straightforward to refit and the lag is defeated.

Adjustable suspension arms – This will allow a complete wheel alignment. More grip for drag, etc.

Half cage – Safety first.

Better seats – I’ve never been comfortable in the S15 seats. My back was sore after the drift day. Bride would be my first choice.

I would consider these essentials. Nothing there in terms of more power, which is sensible. The car is fast enough for what I want, which is a capable all rounder. Ignition system first, stay tuned.

As promised, some media from the Driving Sports drift day on Saturday.

A long drift at the near end:

Linking  half the course:

A full lap of the course linked:

A GIF of a nice slide:

Yesterday was a huge amount of fun! The day ran smoothly and the car was faultless. It has been over a decade since I had done any type of drifting, so I was pretty rusty at the beginning. A few runs in and I was linking turns and growing in confidence. As the day went on, however, my skill deteriorated in the face of mental and physical fatigue. I started spinning from stupid little mistakes that I wouldn’t have made when I was more switched on. Regardless, it was still enjoyable.

The participants were divided into groups of four to six to run on the wet skid pan for about 5 minutes at a time. It doesn’t sound like much but you can have a pretty good go in that time. We had about two runs an hour, with at least sixteen by the end of the day. Dodging other cars as they spun was one of the most challenging parts, but even with six on track it wasn’t hard to find some space.

Early in the day, a fellow participant experienced a small fire when his power steering reservoir spilled onto the exhaust headers. He ended up rejoining later without a power steering belt to avoid a repeat but I’m sure it was a horrible, anxious time as he watched the organisers swiftly descend on his car with fire extinguishers. The lesson for me was to check and wipe small my own power steering reservoir after each run. The day ended up pretty hot but my coolant and oil temperatures were generally in the low 80s as I exited the track. The car was really faultless.

It was also very easy to drive. There were many low powered cars present, especially compared to a drag racing meet. The wet track means very little power is required to drift. My car has plenty of power, so generally only light throttle was required to maintain a slide. I’m very confident that it could handle the skidpan dry without any issues. I ran the car on low boost all day which still provided plenty of grunt.

One thing I struggled with was initiating the drift. The KAAZ 1.5 way diff was very predictable, wit the rear snapping out with any decent application of throttle. With light throttle the car would understeer and plough forward. I was actually surprised by how much rear grip I had in these conditions. I tried to use the hand brake but it needs some tensioning. Yesterday it was far too loose to be reliable and predictable. My favoured method ended up being a ‘clutch kick’. I can see why a 2 way diff would be preferable in initiating the drift with its increased aggression in locking up on deceleration.

In summary, I would highly recommend such a day to anyone with a rear wheel drive car. Over the next bit I will edit and upload some of the footage I took on my VR camera and phone.

 

The car is prepped and packed for tomorrow’s drift event. This mainly concerned loading up rear tyres and tools in the car, but as a bonus, I managed to finally fit the front strut brace.

This originally fouled the rocker cover of the higher S14 motor. I loosened the bolts that hold the centre bar to the mounting plates and tried to exaggerate the slight original kinks by applying pressure to the piece in a vise. Reinstalling with everything as high as possible before tightening gave a good 5-10 mm of clearance. It comfortably clears the revving engine movement and underside of the bonnet. Big success.

Can’t wait for tomorrow, even if scutineering is an hour away and starting at 7:30 am.

I finally finished getting the gunk off the side of the car after removing the side skirts. It’s not a hard job, but does take some time. After the skirts come off, there is a band of rubbery glue on the quarter panels. At first, a chisel is used to pry off the largest chunks, taking care not to gouge the paint. The eraser wheel is then applied on a drill. It gradually rubs the gunk away. I slowly got the hang of it, finding that a slow speed was better. I damaged the paint at one stage from letting too much heat build up (yellow discolouration). The finished result is not perfect but neither is the paint overall, so it will do.

I am booked in on Saturday for my first drift meet with this car. I was gong to do a night event with the Australian Drift Club, but then discovered Driving Sports were holding an all day event for the same price. An easy choice. I’ve paid a deposit and will pay the balance on Saturday morning for a CAMS Level 2 Speed license, club membership and fees for the day. I can’t wait to spend a whole day with this car sideways.

All that was missing was some tyres to burn on the day. I’ve spent the last week scouring forums, Facebook marketplace and Gumtree for some second hand wheels and tyres. Today I picked up what I consider to be a bargain. For $350 I purchased a set of four Rota Grid Rs in 17×9 inches. This is the exact same size and offset (+12) as the wheels that came on the car. Two have decent tyres and two have some inner camber wear. An ideal purchase in my opinion.