New Solution For Mi16 Oil Surge

[boombang 2]

We were having a nice little thread over on PSOOC (as we do) regarding a members new Mi16 build and spec.

 

As per usual oil surge/starvation came up and a number of solutions were put forwarded including the following:

 

Hi guys - just to add my ten pennies worth on surge. as most of you know im well into double figures on Mi16 engines now - number 13 has just gone in with the largest spec to date.

 

My last engine used a standard Mi16 alloy sump - some very very good oil used by the superbike teams and a brand new Mi16 oil pump.

 

With that setup i did 8,500 track miles at silverstone, cadwell, bruntingthorpe, mallory park, curborough and donnington, always letting the car warm up but after that no holes bared and the engine was driven to its limit for every single one of those miles (apart from in lap). that was with limiter set to 8250 on std pistons and rods as well.

 

Not once and i mean not once did my oil pressure needle flicker or move.

 

After 8 years of Mi16 ownership and learning the hard way i now firmly believe (i dont expect many of you to agree) that a good clean well built engine with a good quality race specific oil, regular oil changes and a decent genuine pump is all you need to prevent surge.

 

I wouldnt have wrote this a few years ago - but ive seen it and experienced it 1st hand.

 

Before i this i had tried.

 

PTS baffled sump

PTS uprated springs

every oil on the market (im not kidding)

all kinds of oil filters

larger and smaller oil ways

GTI-6 sump

steel sump

GTI-6 oil pump with and without baffle plate

 

Just thought i would share this with you - it might save some of you some money.

 

Regards

[nick 3]

If it works for him then fair play, but I can't see how anything in his current set-up can stop oil surge.

 

He is basically saying that build a std motor well and it'll be fine (I assume that no-one on here has ever built an Mi engine properly...)

 

A brand new pump won't make the slightest bit of difference, it will give good pressure when the oil is there, but when the oil ain't there you could have 10 brand new pumps working together and there will still be zero pressure.

 

It does seem strange with the Mi engine that some surge and some don't, I suppose he just got lucky this time!

 

Or have we all imagined the oil surge.........

 

Nick

[Doof 11]

Is it actually that some surge and some dont or could it possibly be inaccuracies in the senders / guage meaning some show it more than others?

 

Certainly with an intermittant thing like this I would think electrical issues would be more likely the cause than mechanical.

Edited September 26, 2006 by Doof

[James_R 3]

Sounds more like he's had a lazy needle, or changed to some tyres which loose tractoin at the point you'd normally surge.

[crf450 0 1 Cars]

Perhaps he's just not going fast enough.

If there wasn't a problem with the Mi engine why did Pug go to such lengths with the engines that followed the Mi to stop it.

[kate205gti 4]

8250 on std pistons and rods

 

would that not blow up??

 

be very interested to know the spec of the last engine, and if that engine oil in a different engine has the same effect thou!

[Anthony 1,000]

Doesn't add up to me - after all, if the oil isn't draining back from the head properly, it doesn't matter one iota whether you're running race oil or lawnmower oil if the oil isn't there for the pump to pickup. Besides, if it were an oil quality issue then you'd expect 8v's to surge like hell as well given that alot of the bottom end is very similar, and clearly they don't.

 

would that not blow up??

Momentarily it would probably be OK, although holding it there continuously would be asking for trouble. My old standard Mi lump (one that Doug now has) exceeded 8000rpm on a downshift when I was trying to slow the car after the brakes failed, and that didn't gain any additional rod-shaped ventilation holes in the block...

[Rippthrough 98]

Doesn't add up to me - after all, if the oil isn't draining back from the head properly, it doesn't matter one iota whether you're running race oil or lawnmower oil if the oil isn't there for the pump to pickup. Besides, if it were an oil quality issue then you'd expect 8v's to surge like hell as well given that alot of the bottom end is very similar, and clearly they don't.

Momentarily it would probably be OK, although holding it there continuously would be asking for trouble. My old standard Mi lump (one that Doug now has) exceeded 8000rpm on a downshift when I was trying to slow the car after the brakes failed, and that didn't gain any additional rod-shaped ventilation holes in the block...

 

 

The motorcyle oil bit doesnt add up weither - bike oils are different for a reason - they contain no friction modifiers because most bikes have a wet clutch - so the bike oil would be increasing the internal friction even compared to cheap semi-synth.

[PumaRacing 1]

I'm just glad he has a policy of 'no holes bared'. Sticking your arse out of the driver's window while hooning it round a track is so 90's.

[maturin23 10]

That's an unpleasant and enduring image!

 

[boombang 2]

I've not mentioned any names on purpose - but lets just say he runs a Peugeot breakers that also claim to do some tuning.

[yorkdave 1]

i'm a mechanic by trade, and don't claim to be the best in the world. but there is no way the type of oil can make a difference! unless it is so thick that it isn't protecting the engine any way! i rebuilt my mi with a group a pump spring and still experienced oil surge just running yokohama a539's. If the oil has surged away from the pump it hasn't got anything to suck up and create pressure with. end of story.

[Jonmurgie 2]

I've not mentioned any names on purpose - but lets just say he runs a Peugeot breakers that also claim to do some tuning.

Isn't is SPOOXY that this place crops up so often now...

[boombang 2]

What Yorkdave said pretty much sums up my comment on the orginal thread, that you cannot cheat physics!

[Batfink 201]

maybe the needle is broken

 

reminds me of a saying.. "If a tree falls over in a forest and no-one is there, does it make a sound"

 

Sadly its pretty much fact the mi16 head is the culprit, but there are a number of solutions that work one of them is driving like Grandma round the circuit. Maybe thats it

[Miles 331 1 Cars]

I just love posts like this, Oil surge is all relative to Driver ability, I seem to remember a crash at Prescott.

I ran my old Mi completly std for a season with minor surge at Oulton Pk and allot at Thruxton before it went bang, the Rev Limit was set to 8500rpm as it made max power at 7750k

[welshpug 1,622]

Sounds more like he's had a lazy needle, or changed to some tyres which loose tractoin at the point you'd normally surge.

 

 

Perhaps he's just not going fast enough.

 

I know of the guy in question, he's had 13 different installations so unless he's had some really bad luck I doubt it!

 

And I know of his driving too, so the second quote doesnt apply either

 

It would be good to find out for definite what exactly does happen, surely some oil level sensors could be placed in the areas concerned to see if oil really does collect/surge this badly.

 

You have to bear in mind that most of the Mi16 conversions have utilised well used engines and would be more prone to low oil pressure.

[Duroc 2 1 Cars]

It would be good to find out for definite what exactly does happen, surely some oil level sensors could be placed in the areas concerned to see if oil really does collect/surge this badly.

 

I've fitted a mechanical oil pressure sender to my recently rebuilt Mi16 (which has no sump baffling), as the standard gauge/sender is so unreliable. Took it to a trackday (RAF Honington) last weekend, and in one very tight righthander in a chicane the needle would momentarily dip to nothing! Other parts of the track it would dip to as low as 18-20 psi. Needless to say I took it a bit easier after the first couple of times.

[Baz 421]

You have to bear in mind that most of the Mi16 conversions have utilised well used engines and would be more prone to low oil pressure.

Why? I'm sure you know as well as anyone else here, and as already pointed out in this thread, it's a characteristic of the Mi's head not returning oil efficiently to the sump to pick it back up again. New or old, again, you cannot beat physics!

[d-9 0]

Why? - because on an old engine the oilways will be full of crap. As most engines that people are fitting these days are rebuilt that shouldnt really matter thou.

[Baz 421]

A valid point i suppose! I just presumed that no one would be silly enough to fit a tired / neglected / sat around / thrashed / high mileage engine to a car they're expecting to be half reliable. Serviced properly and without silly high miles there'd be no reason why the oil ways would be full of crap really?

[d-9 0]

A valid point i suppose! I just presumed that no one would be silly enough to fit a tired / neglected / sat around / thrashed / high mileage engine to a car they're expecting to be half reliable. Serviced properly and without silly high miles there'd be no reason why the oil ways would be full of crap really?

 

 

*looks innocent*

[Rally Slag 0]

this might sound silly but what about putting like 0.5-1 litre extra of oil in the engine, mayby not so good for a road car as it needs to be reliable, but round the track wouldnt that do that trick?

[Baz 421]

*looks innocent*

 

What do you mean Doug!?! I suppose can't say alot, just about to put an S16 in a 205 with only a minor refresh, but i know it hasn't done a gazillion miles, ran well when it was removed and was always serviced well! Still, not expecting miracles from it! If it breaks, it breaks!!

Edited September 26, 2006 by BazGTMi

[Miles 331 1 Cars]

Even the fully rebuilt engines suffer from this and even when I had Mi16's when they where new the stop light came on around bends (No oil pressure guage in these), The oil pumps don;t wear much at all due to the design and I;ve only had the pattern one's give any problems.

When you do fit a proper oil pressure guage you'll just see how much it moves around