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JeffR

[trackday_prep] 405 Mi16 Track Car

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JeffR

Unfortunately the first event after the dyno session for the new hybrid 2.2 litre didn’t go according to plan.

The first run was only to bed in the new brakes (DS3000 pads & std 406 rotors) and was a success after being dogged by major vibrations in the past.

In the second session I was getting low oil pressure dash warnings. Not to be ignored being a new (2.2 litre) engine, it needed investigating.
We spent the next break between runs trying to work if the low pressure was significant or a false signal. We determined, based on the temperature of the line to the remote sensor, much cooler than all the other oil lines that it was an airlock between the oil gallery and the sensor. This will be rectified in future.

Unfortunately our concerns meant we failed to set the tyre temps to the optimised 29psi and were way too high (+5psi).

So run 3 and I only managed one lap before all hell broke loose and needed a tow back to the pits. Turning the engine over on the starter seemed like no compression.

Back home in the garage with the head removed at least 12 valves bent, possibly all need replacement and cambelt snapped. I’ve asked to check for valve guide and seat damage and to set the spring seat pressures as well.

Further investigation has shown a 13mm bolt from the front tensioner had loosened and flung around the cam belt until it jammed the water pump.
 
Still to determine if any damage to the pistons, rods or bearings.

IMG_1090.JPG

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Edited by JeffR
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Anthony

Oh s**t, bad times :(   All that hard work undone by a bolt worth a few pennies - hopefully it's "just" some bent valves.

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michael_ozzie

What rotten luck Jeff, hopefully the damage is limited to a few easy components, after all that hard work.

 

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JeffR

I got some good news back from the company tasked with repairing the cylinder head today.

With the inlets, we’ve decided to get John White at Competition Valves to make me a new set with a single groove, supply the collets as well as lengthening the stems. This’ll allow the lash cap shims to sit on the valve stems in the conventional way.
John had done quite a bit of development work for PeterT and the late Owen Wuillemin in the past and will make a set which will flow better that what was installed.

The exhaust valves are std so a new set will be fitted and there is no damage to the seats or guides either-phew!

Seat pressures and valve clearances will be set as well. There’s possibility the clearances might change one the head is refitted. A small inconvenience in the scheme of things.

The only good thing to come out of the Sandown debacle was a good action pic!

Sandown 23.6.19.jpg

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JeffR

A further update today after removing the pistons this afternoon. Other than some bruising on the piston crowns they appear to have survived the encounter with the valves as have the skirts and cylinder bores.
Big end bearings will need replacing as I expected.
The company handling the rebuild told me today that when they were removing the inlet valves, the head dropped off one as soon as they compressed the valve spring to remove the collets.
So a disaster as things went for a 6 hour old engine could have been a lot worse with just a few more piston to valve collisions before further damage.

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JeffR

I finally have the car back together in readiness for a track test. Hopefully one of the organising clubs will have a sprint session down the road at Sandown early in the new year.

With the cost of repair, I’m considering not having it dyno’d again so I have to decide how much extra fueling to add with the new inlet valve profile. Compared to the old ones they’ll have better flow both by the back shape and 6mm wasted stem.

 

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Tom Fenton

I hear the pain to your wallet, but I would not advise running it hard without at least a quick dyno session to prove fuelling is sufficient.

Lean equals heat can equal further problems!

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JeffR

Thanks Tom, I'm aware of the pitfalls of running it lean and with it coming up for sale don't want to hand over a grenade to the new owner. I thought 10% might be a safe figure at least to begin with.

Not only the wallet having been severely lightened but my regular tuner is usually booked out a couple of months in advance.

I 've since thought of another tuner not close but he's a regular for an Improved Production 306 and a 309 Gti16. I'll make enquiries.

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JeffR
Posted (edited)

Time for an update.
As per my previous post I was reluctant to spend more $$$ on the car. I umm’d and ahh’d about (the spend) for a few months but in the end I convinced myself that a), the upgrade to 2.2 litres didn’t achieve the hp I expected -the black line and b) I still wanted to sell a car in top mechanical condition.
Paul, my tuner had previously identified the shortcomings of the exhaust system. It has one of Miles 4-2-1 manifolds thermally heat treated inside and out, a mish mash of hotdog and pipework to a rear Devil rear muffler probably only designed for a standard engine to give a nice note.The pipe diameter might also not suit the high horsepower intention.
So, cheque book out and the cam specs, inlet valve stem diameter and cam timing were provided for a new extractors back system to be made.
The combination of the new exhaust, the better profile of the inlet valves as well as a wasted stem in the port area (7mm - 6mm) gained a significant power increase. The only disappointment I couldn’t find a road tyre/rim offset combination to clear the Brembos and coil over spring platforms for the power runs and cost myself around 5-6Kw by using the AO 50 Yoko race tyres.
Now the result will probably be underwhelming to those in the Northern Hemisphere because you calculate you’re power in a different way. Likely flywheel power is around 180 - 190 Kw.
But here’s the result the way we measure things in Oz.

IMG_1259.JPG

Edited by JeffR

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Tom Fenton
1 hour ago, JeffR said:

Likely flywheel power is around 180 - 190 Kw.

I've done a quick rough conversion, because kW mean nothing to me, and likely most of us in the UK

 

240-255bhp approximately, which is very strong power!

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JeffR

Yep the spend was probably worth it.

 Disappointing is that the new regs for 2020 Super Sprint now require a Hans device and since I'm selling the car  and don't want to invest in a new helmet as well means I won't get to drive it. Ouch!

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Andy

I think that is an excellent result. 191hp at the wheels is pretty impressive.

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speaksgeek
Posted (edited)
On 3/27/2020 at 10:23 PM, JeffR said:

Yep the spend was probably worth it.

  Disappointing is that the new regs for 2020 Super Sprint now require a Hans device and since I'm selling the car  and don't want to invest in a new helmet as well means I won't get to drive it. Ouch!

I could take it for a run for you if you like, for science :D

Edited by speaksgeek

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JeffR

Thanks. I’ve had a few ‘R & D’ offers too!
Maybe when things are less bleak I can get it up to Winton for a test & tune day. No scrutineering so no HANS device req’d.

 

BTW-I've advertised it on Aussiefrogs here-

http://www.aussiefrogs.com/forum/cars-sale-wanted/138755-405-race-car-sale.html

 

and nationally here-

https://www.my105.com/ListingDetails/p/4/cid/518/id/22164

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JeffR

While I had the car on jacks to refit the under tray today, I took a few pics of the new exhaust.
First up was to replace the 2-1 merge collector which came with the extractors. Not a good flow for a performance engine. I kept the spring joiners from the extractors. IMG_1338.thumb.JPG.d2389b2179c23f6cdcfbd86fe42c984e.JPG

A centre resonator (hotdog) and pipe work much tidier under the fuel tank and rear beam. I also had a heat shield applied to the bottom of the tank and the pipework wrapped.IMG_1341.thumb.JPG.a40a918eea4058fd3f972e89735782a8.JPG

 Finally a large better flowing rear muffler to hopefully keep the noise levels to around 85Db.IMG_1340.thumb.JPG.942000900cd4ab72e994a422826af52e.JPG
Really pleased with the workmanship.

 

On another note I’ve been asked why I quoted a different power figure (195hp) in the links where it’s advertised for sale when the dyno sheet showed a lower figure (191hp).
In my March 27 update I mentioned I used my race tyres on the dyno combined with 3° neg camber (which I failed to mention) and my tuner said it cost about 5-6Kw that the engine produced but couldn’t be measured because of wheel slip. The camber made the contact patch on the rollers about half the tyre width which added to the problem.
Taking his remarks on board the likely figure is around 148-149 wheel Kw’s (198-199hp) so I split the difference at 195 for the advert.

I should have been clearer when I wrote up the report but there was no attempt to deceive or misrepresent the result.

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IRISH_MI16

195 at the wheels is bloody impressive! I'm aiming for that with mine whenever I get round to building the engine for it. 

Hopefully we get another video of that on track before it finds a new home 

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JeffR

While I was cleaning up my data notes on the 405, I thought it’d be a good exercise to plot the last dyno run of the 1.9 engine compared to the current 2.2.
The overall maximum increase of 14Kw only indicates part of the improved result.
In the 4500 to approx 7200 rpm the difference is appreciably greater with gains upwards of 25Kw.
I didn’t have a comparable torque figure for the 1.9 as it was expressed as Tractive Effort, and difficult to convert to Nm.
I think a number of factors were responsible for the improvement-
1. Larger bore 87mm up from 83.5mm so unshrouding the 36.5mm inlet valves,
2. Better valve profile and wasted stems in ports-6mm instead 7mm,
3. Improved exhaust system more aligned to the engine spec.

IMG_1383.thumb.JPG.7496d5c52a886f0fc4f2fdfbfa856cca.JPG

 

To convert-
Kw to Hp x 1.33
Hp to Kw x 0.75

 

I’ve been offered a loan of a HANS device and helmet so might get to drive it when motorsport begins again.

 

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IRISH_MI16
6 hours ago, JeffR said:

While I was cleaning up my data notes on the 405, I thought it’d be a good exercise to plot the last dyno run of the 1.9 engine compared to the current 2.2.
The overall maximum increase of 14Kw only indicates part of the improved result.
In the 4500 to approx 7200 rpm the difference is appreciably greater with gains upwards of 25Kw.
I didn’t have a comparable torque figure for the 1.9 as it was expressed as Tractive Effort, and difficult to convert to Nm.
I think a number of factors were responsible for the improvement-
1. Larger bore 87mm up from 83.5mm so unshrouding the 36.5mm inlet valves,
2. Better valve profile and wasted stems in ports-6mm instead 7mm,
3. Improved exhaust system more aligned to the engine spec.

IMG_1383.thumb.JPG.7496d5c52a886f0fc4f2fdfbfa856cca.JPG

 

To convert-
Kw to Hp x 1.33
Hp to Kw x 0.75

 

I’ve been offered a loan of a HANS device and helmet so might get to drive it when motorsport begins again.

 

Im getting swayed more and more towards doing a 2.2 and those results are hard to argue with. Especially with how torquey it should be 

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JeffR

Since I’ll be selling up and moving in the new year I’m getting ready to put the car and trailer into long term storage when we are released from Covid lockdown (hopefully next week), or until it sells.

IMG_1472.jpg

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