[trackday_prep] 405 Mi16 Track Car

[JeffR 51]

Took the Mi16 out to Sandown yesterday for its first run this year & first time against the stopwatch.
Sandown is in suburban Melbourne and has a 75db noise limit for all events other than the V8 SuperTaxis.
Once the track dried out from an overcast & drizzling morning I managed to get black flagged for excessive noise registering 78db as measured on the main straight. Strange as I've been running the same induction & exhaust for 10 years without incident, but arguing that point with the Clerk of Course was one I was never going to win!
It was agreed that if I ran the main straight on part throttle, like a granny, I could continue for the day. A bit frustrating but better than going home blowing my $220 entry fee.
I noticed later in the day the noise tester had left, so gave it everything for my final run & set my best ever lap & 8th fastest (of a small field) on the day-

http://racing.natsoft.com.au/results/#2

The car ran flawlessly throughout & other than oil temp being too high I was pleased with its performance. I'll pick up a 19 row oil cooler which being 50% larger than currently fitted, should aid bring the temps down.

 

 

 

 

 

Edited February 17, 2014 by JeffR

[JeffR 51]

 

[JeffR 51]

With another sprint day coming up soon (April 5) at Phillip Island, it's been a good opportunity to deal with a few issues that cropped up from Sandown.

I replaced the 13 row oil cooler with an approx 50% larger Serck one. Had to enlarge the opening in the front bar, so fingers crossed this brings the temps down from 120˚ C by around 10-15 degrees.





Also found the existing shift light which comprised of one LED wasn't prominent enough to catch my peripheral vision especially when sunny. Swapped it over for a nice lightweight Motec 12 LED type.





I dropped the rear ride height another 10mm to get a difference of 12-13mm between front & rear.

My starting point with the Gaz shocks was full soft all around. The rear appeared to be quite bouncy as seen from the external video (see previous post) so this time I'll go 1/2 way between soft & hard (18 clicks). Turn in seems good with 1.3˚ neg camber & max caster, so unsure whether to stiffen up the front as well.

[JeffR 51]

Update-

 

I've decided that rather than having the threat of getting black flagged again, I should reduce the induction noise & keep the noise police happy.

The open fronted arrangement I had with holes cut into the slam panel to allow the bodies to breathe was why it was above the 75db limit which is in force at all the tracks down here. It was always a bit of an agricultural effort so was a good excuse to bling it up!



I picked up a fibreglass airbox & went about rearranging the engine bay to make it fit. Moved the oil filler to a new point further back, had a new coolant fill pipe made with a longer neck also repositioning it further back, made a bracket & mounted the map sensor on the accumulator and moved the coolant overflow bottle onto the bulkhead. Made a plate between the radiator, airbox & filter which also blanked off the holes in the slam panel from the previous air intake.

The airbox had a crappy method of attaching the two halves, so I picked up some over centre toggles which have provision for a tie wire or similar to prevent them from accidentally coming apart. I had a box of assorted split pins, so used them instead.

Fitted a K&N pod filter enclosed in a box & enlarged the original intake through the grille to a surface area to match the 4" filter & airbox intake & joined the two with some 4" scatt hose.



I spoke to my engine tuner regarding the new induction set up with the current mapping & he reckons the map sensor will compensate air/fuel ratio to a degree, and if anything, likely to run richer. I might even pick up some midrange torque.

So should be OK until I get it back on the dyno sometime after Phillip Island.

[JeffR 51]

Phillip Island is a brilliant track and I finally cracked a sub 2 minute lap (1:59.3) on the 4.445km circuit. Oil temps came down to about 110° with the bigger 19 row recently fitted.

There was a slight high speed misfire which probably is a result of changing the airbox/induction system so hopefully we'll get sorted when it goes back on the dyno on the 28th.

 

 

 

Next month (4th May) is the Rob Roy hillclimb event & Sandown again on the 10th. Rob Roy is the second oldest hillclimb in the world behind Prescott in the UK being the oldest.

[calvinhorse 870]

Great video

 

Keep the updates coming, any more plans for the car?

[JeffR 51]

Got to sort out my gearbox ratios. I set out to use the Mi's 1st & 2nd and the early 205's 3rd, 4th & 5th but something went wrong along the way with the clusters & main shafts I had at hand. I've finished up with a really short 1st gear which will hurt at the hillclimb next month.

Longer term will be a stroker bottom end using an iron block, 88mm diesel crank with anything between 86 & 88mm bore & forged pistons.

And my neighbour's daughter is calling into Peugeot Sport in Velizy in a few weeks to get me some decent clothing!

[calvinhorse 870]

Yeah I was gonna comment on your awesome race shirt

[JeffR 51]

Dyno day was cancelled due to the tow car playing up-bugger. Will have to be rescheduled for another day.

 

My day was brightened up though by what the Easter bunny delivered! A 13/68 final drive from Bacci Romano. I knew if I went easy on the Easter eggs, something good would come of it!

 

 

At least it's given me the opportunity to collect what I need to make a better gearbox for the car. I had a 'mystery' box with unknown ratios, but upon opening it up I found it has exactly the ones I want to go with the new final drive. I've also decided to jettison the Quaife atb for a proper plate diff now that the car is no longer road going. It'll be a 3J Driveline NXG.

 

It'll be touch & go that the Ford can be fixed in time for this weekend's hillclimb at Rob Roy.

[JeffR 51]

Wasn't able to make it to the hillclimb recently due to the tow car playing up as mentioned. Not necessarily a bad thing as the weather was wicked anyway.

 

The high speed misfire I had at Phillip Island was confirmed as a result of changing the airbox over to an enclosed type. We got it back on the dyno last Wednesday where a resonance in the new airbox was discovered. The map sensor couldn't fully compensate for it, so a restrictor was fitted into the line to dampen the pulses and the remaining variations were tuned out (a layman's explanation).

 

We also raised the rev limit to 8000rpm to suit the new gearbox/final drive soon to be installed.

 

All done in time for me to run again at Sandown last Saturday. Unfortunately, the weather was crap-rained all day but at least the car ran like clockwork.

 

 

 

 

...and my debut in Peugeot Sport livery!!!

 

[JeffR 51]

Update time....

My new gearbox is built and re-installed with a shorter 3rd, 4th & 5th ratios along with a 5.23:1 final drive. While the box was out it was also the obvious time to fit the 3J plate diff.
On advice from Dan Jones at 3J Driveline we have gone for 60-65lbs/ft preload & a 40/90 ramp angle. For the run in phase, I'll use standard 75W/80 Peugeot oil with a bottle of Penrite LimSlip friction modifier on hand if I get any chatter.

In removing the box I decided to take it out with the engine attached & check the rod bearings since I'd noticed the oil pressure drop to 20 psi on the double left hander onto the straight at Phillip Island earlier this year on one of the in-car videos.
All good but I reckon I owe it to the accumulator for saving it as that pair of corners is a known engine breaker (don't ask how I know)!

In a conversation with PeterT about the oil pressure, he found the time the accumulator takes to empty its contents into the engine was a lot longer with the solenoid operated valve that the manual tap the unit came with. I had previously timed the solenoid version at around 25 seconds.

Armed with that info, I retro fitted the manual tap & timed how long it took to discharge-only 10 seconds!

 

 

Air filter v 3.0.

Having found the short piece of scat hose between the airbox & filter was torn due to engine torquing even with Baker mounts, I decided rather than persisting with bringing air through the slam panel I'd use the passenger headlight instead. I had a spare unit which I removed the glass from & cut out the rear leaving just enough of the plastic for the spring which holds the indicator in place. I shaped a 2mm piece of alloy and shaped a bell mouth into it to aid flow.

Since the filter is right behind it, I shaped a deflector so any rainwater is directed above & below the filter to prevent ingress into the engine and can drain out due to the angle of the box.

 

 

I should find out how successful it is this Saturday back at Phillip Island with rain & 12° predicted. I also took the opportunity to blank off 1/2 the oil cooler & apply Rain-X to all the inner glass!

Edited July 10, 2014 by JeffR

[JeffR 51]

The day at Phillip Island was a disaster. I was running about 30 mins late and everything from the time I arrived was rushed.

Rain & hail while I got the car off the trailer. Last car to scrutineering, just made the drivers briefing and a scramble getting on to the grid for the first practice session & soaked to the bone as well.

Within 3 laps got black flagged for an unsecured bonnet and on returning to the pits also found the engine had emptied about 5 litres of oil out through the catch tank breather all over the engine bay, wheels, brakes & onto the track. I'd popped the bonnet to open the accumulator tap but with the rush of trying to get onto the grid completely forgot about it. That brought everyone's day to a halt while the track was cleaned up. There was no sense continuing so put the car back on the trailer & was back home by midday.

I need to investigate what caused the spill, suspecting the closed accumulator played a role in it. I may move it into the cabin within easy reach when strapped in.

The only positive was the performance of the gearbox & plate diff.

[petert 550]

Say to hear all that Jeff. I always shut off the accumulator while the engine is running, before checking the oil level. Once you've got the correct level in the sump and the accumulator full, you shouldn't need to touch the valve again. It doesn't matter that you might start the engine with 7L in the sump. It will soon push the extra oil up to the accumulator until it's needed.

 

If you want to take it one step further, you can put an extra mark on the dip stick, which is the addition of sump + accumulator.

[JeffR 51]

I was puzzled at the time I filled the engine with oil. 7.5 litres seemed too much, but thinking of the extended sump, oil filter, 19 row oil cooler & accumulator after starting the oil level was OK. I did mark the dipstick with a level for when the accumulator tap is open.

 

What I don't understand is if it was overfull why didn't it pump out say, 1-2 litres through the breather then stabilise rather than almost all of the oil leaving only 3mm showing on the dipstick?

 

Maybe I should seriously consider a Pace dry sump system. No venting to atmosphere, so no concerns of external spills.

[JeffR 51]

Update-

I found my oil leak was due to the feed hose from the accumulator into the engine was loose and not from an over flowing catch tank as I first thought. No-one to blame, just an oversight.
It necessitated fitting new front pads since the old ones were saturated in oil so I went for a set of DS3000's. The previous unidentified pads were chamfered on the front & rear edges whereas the 3000's fully cover the entire backing plate, so it effectively gives me a bigger pad.

Also found the front 400lb springs had gone coil bound, so it's now fitted with 550lb spec.

By upping the front spring rate I'll probably need to further stiffen the rear beyond the 23mm t/bars currently fitted at some stage.

I'm entered at Sandown on the 21st and should be able to evaluate the brakes, suspension, plate diff & 5.23 final drive.

I'll post some footage in the week after.

[camgti 56]

Nice work jeff,

 

Great to see you persisting and getting on with it!

 

Cam

[petert 550]

Good luck for the 21st. I'm keen to hear how it all goes. Lot's of significant changes!

[JeffR 51]

Hoping for some dry weather in the week leading up to it as the V8 Supercars are running the first of their endurance rounds this weekend with the Sandown 500 and will have laid down plenty rubber for me to take advantage of!

[petert 550]

If all goes well, maybe you'd like to enter Wakefield on the 26th October? We're going to stay Saturday night at Wakefield Park. Apparently it's only $60 per person.

[JeffR 51]

I'm keen to give it a run at Wakefield. Unfortunately it clashes with the French Car Festival in Melbourne that weekend. I haven't got much value from my CLA membership for this year!

[JeffR 51]

Really pleased with how the car performed on Sunday aided by good weather & no wind.

The stiffer 550lb front springs, DS3000 pads, 5.23:1 final drive & plate diff. I found no need to use fancy gearbox oil or friction additives as there's no chatter from the 3J lsd.

 

Everything worked together and I improved my previous best time by over 5 seconds.

Car was much easier to drive on the limit and I finished 4th fastest under 2 litre & 14th fastest overall from a field of 86.

Only issue was reaching the rev limit well before the end of the straight. I'll change for a longer 5th gear for the next meeting.

[petert 550]

Excellent work. What rev limit were you using?

[JeffR 51]

8000rpm. I was thinking of getting it mapped to 8250 for a bit more headroom.

[petert 550]

I definitely would, before changing 5th. I use 8200 regularly.

[JeffR 51]

I was on the rev limit for about 200m that's why I thought a 5th gear ratio change would help as well.