A day on the Dyno

[millermilla]

I booked the rolling road session as it felt as though the car was leaning off on partial throttle which made it a bit of a pig to drive around town. It went well on full throttle but nothing in between so the throttle was more like an on / off switch. I drove down to Gerald Dale Motorsport in Ninfield this morning for a run on the rollers and to have the needle re-profiled. The first thing he done was set the mixture at idle speed. It was running at about 6.5% CO which is a bit too rich as I had tried to compensate for the weak needle trying to make it run better on a light throttle. With a quick adjustment on the mixture screw it was back to around 2.5% where it should be. The front of the car was then held down firmly on ratchet straps, a large fan was put in-front of the grille to blow cold air into the radiator and an extractor fan connected to the exhaust to take away the exhaust gasses. Various probes were connected to the engine to monitor it's vital signs during the power runs.

I had estimated the power to be around the mid seventies but with hindsight although it did drive badly it still pulled like a train on full throttle so I was pleasantly surprised to see the first official power output reading of 87.3bhp @5309rpm and 94.1 lbs ft @4510rpm. To be honest I was quite pleased with that as even though it was running badly the torque was up about 7lbs ft from standard and the BHP was down by only 7BHP. For a 19 year old car that’s not bad. Seeing and hearing the car going through the power run is an experience in itself. Its not often you get to stand 2ft infront of a car while its doing 105mph on full throttle seeing the turbo glowing red down the back of the bulkhead. It's also pretty damn noisy too!

Gerald now had a good idea of the problem and it was clear seeing the readings on the exhaust gas analyser that it was running dangerously lean on partial throttle. A few minutes later Gerald had removed the dashpot and was profiling the needle by hand which is a real art gained through many years of experience.

The second power run instantly sounded different to the first. You could hear the engine was smoother, the turbo seemed to spool up faster and it just sounded more determined. You could see the car really pulling on the ratchet straps trying to make a bid for freedom, thank god it stayed put! The final outcome was outstanding. The car is standard bar a Maniflow 2" exhaust system and the factory figures which are often quite hard to match even from new were 94BHP at 6130rpm, torque 87lbf/ft at 3600rpm. I was very pleased to see it give 94.4BHP at 5050rpm which being lower in the rev range makes it a lot more useable but it was the torque figure which amazed me 102.8 lb ft @ 4141rpm which is 15.8 lb/ft more torque than it left the factory with! It would have been quite easy to start fiddling with the boost pressure, winding it up and 100+BHP would have been easily achievable but that wasn’t what I wanted. What I wanted was the car to run as best as it can how it was originally setup and that’s just what Gerald done.

As you can guess the spirited drive home was lots and lots of fun and it was a nice feeling to know it was running so sweet. :driving: In all it cost £103.50 for the rolling road session which I have to say is probably the best £103.50 I've ever spent on a mini.

[G96LUE]

That is quite impressive for a standard spec engine.

I still need to get mine booked in for a rolling road.
It has only been tuned by hand by myself since the new engine was fitted. I needed to run it in before it was subjected to a rolling road thrashing.
Mine sounds like it runs similar to yours did. At full throttle it is fine, but it hunts while trying to keep a steady speed.
I now have some 1.5 roller tip rockers to fit which i might do tomorrow
then see about getting it booked in at Aldon Automotive for a rolling road.

It is a 1310cc MED engine so i am expecting it will be over 100bhp on standard boost.

When i get round to it i will list my results.

Regards

Darren

[paul]

Impressive I said it went better than the Black one.

Paul

[Jezza]

I had mine tuned up in March at HiTech Motorsport in Cradley Heath (in the Black Country).

New needle (£11) and an hour or so of expert tinkering and it was a different car!

96BHP (at 6,241 RPM) and nudging 105lb/ft torque from a pretty standard ERA 1275 (some mild headwork back in 2000 when the engine was rebuilt).

£82 all in!!!!

I recommend it to anyone.

[G96LUE]

Hi Jeremy

Thanks for this recommendation, do you know if they open on Saturdays?

Aldon only open on weekdays which makes it a little difficult to get too.

Any problems holding it down to the rollers? did they use the front tow loop? i ask this as mine (being a replica) does not have one.

This place is slightly closer than Aldon too, but only about 3 miles though.

Thanks again

Darren

[Jezza]

Not sure on Saturday opening at Hi-Tech but most places are open Saturday mornings.

No problem on the rollers with no need to tie the front down.

I have also previously had a Mini (1293 injection ex-race engine with custom ECU) rolling roaded at Aldon in Brierley Hill around 5 or 6 years ago and they were fine though I think a little more expensive than Hi-Tech.

[G96LUE]

I've finally had a day at the dyno too.

I'm still not happy with the drivability upto 3000 revs and the tuner says it is the cam's fault (MED 1310 engine with T3 cam).
The cam only cuts in at 3000 rpm

It is better than it was before though.
After 3000 though the engine comes alive.
Power at the wheels = 94bhp @ 5488 rpm.
Torque at the wheels = 98lbft.

The only problem now is it is smoking a bit. i'm not sure if it is the turbo, but there is oil getting into the plenem so that is why i suspect that.
There was also some puffs of smoke coming from by the turbo under the bonnet as if oil was dripping on it but i cant see where it was. Guess the engine is coming out again after the imm.
Think i will get a standard mg turbo cam and a new turbo for it.

[millermilla]

They're pretty good figures for wheel horsepower and torque. Oil in the plenum can only come from the turbo but there will always be a little oil there just not alot!

[G96LUE]

I'm not sure how much oil there is in the plenum but i know there is some as i get a small amount come out of the vents on my bailey dump valve.
compression was ok in the cylinders so it shouldnt be burning oil from there.
The tuner suggested that there might not be enough back pressure in the exhaust (single box stainless RC40) for the turbine at tickover ?

it does appear that the smoke starts during tickover and after a bit of driving it clears up. If i kept the revs over 1500 in traffic the smoke did seem to be kept at bay, however deceletaring on the motorway i did make a small cloud.

The realy strange thing that i cant get my head round is this, With the bonnet up there were puffs of smoke coming from the turbo area. we couldnt see any oil but it seemed as if a drop or fine spray of oil was hitting the hot turbo and vapourising. there is no sign of an oil leak though.
On my way home, everytime i stopped in traffic and let the car idle after about 10 seconds i got the oil smoke coming from my bonnet vents and at exactly the same time the batman smoke screen starts behind.
I can't figure this one out.
There is no sound as if the exhaust manifold to turbo or turbo to down pipe is blowing but this is about the only place i think i can get smoke from the front and back at the same time.

Anyone have any other thoughts.

Regards

Darren.

[paul]

Hi Had HiTech do mine today as well, they said it was the third ERA this week so including Darrens' there was another in as well.

Mine has never been set up properly since I fitted new seals when it came over as it wouldn't run right then. I was cautious and set it rich for fear of melting pistons, recently ( on way back from IMM2008) it developed the odd miss under load and acceleration.

When I booked it in they said don't do anything to it we want it as it is playing up so easier to fault find. fair enough but I did notice the number one plug lead which on mine runs up through the alternator bracketery as it has A/C sparking out onto the alternator now and again, so lead breaking down from rubbing on the alternator bracket was a given.

So I arrive they put it on the rollers and it just clears by about half a CM Jap ones have the number plate box on which comes down even lower than normal.

Ticking over in their dimly lit garage you could see the odd spark to the alternator of mumber one lead which was noted.

Lead off no suitable lead available to head of lead wrapped in insulation tape twice and a bit of rubber tube half wrapped arround cap of lead to insulate from alternator.

Plugs out compressions checked and all bang on plugs checked and gapped a little big before and rich looking. back in and probe up the pipe and CO 6.5 yup nice and rich! he backed it down to about 5 and it wouldnt go any lower, top of carb off and jet is about 1.5mm below level and wont adjust any higher, so something wrong in the bottom of carb perhaps? anyhow, needle looks worn, so new needle tried and co drops right down to 2.25 or so looks happier and gives it a run and rev through range, going fairly lean mid range so stops tinkers tries again better. Adjusts acelerator cable and tries again seems happy gives it a power run on the program, happier though still lean low down. Top of carb off a little swiss file work and another go. Tap on the dizzy to change timing a little. Final go and Happy operator.

Results.

100BHP peaking at 5900RPM
98 ft/Ib torque from 3500RPM through to 4500RPM.

He said it needs carb off and rebuilding as the jet possibly isn't centred correctly? And fit a higher pressure acutator and this one will easily pull 130BHP.

Drive home the dreaded mis back worse than ever, felt most narked through the rush hour traffic back to the M5, floored it up on to the M5 once it hit 3000RPM goes like a scalded cat, most impressive, but part load still missing, in the roadworks on M6 with 50MPH speedlimits pain in bum missing trying to keep it at 50MPH. Dropped by motorfactors picked up some leads plugs cap and rotor and started it outside wouldnt idle kept cutting out.

Got it home pulled bonnet and found the vapour recovery pipe from the carbon canister had come of the t piece in the servo pipework leaking vacum to atmosphere so that was dropping revs a little, changed leads and plugs left cap and rotor for now and will see in morning it that cured idle and mis. Also noted the dashpot clamp had not been refitted so will give them a call in the AM and ask to post back to me! I think I have a spare down the garage to use for now.

Price was 90 labour 10 for a needle and some VAT 115 all in very happy with that