What Engine for 500BHP

[turbonutter]

Thanks for all the replies,

Flywheel is steel & I was also wondering if the washer was needed... its an OEM part sold by alfa as a securing plate.
I also enquired on an alfa forum and it apears that some variants of the v6 have the washer and some dont...
As stated above, the bolts are fitted with thread lock, so it seems the solution is simple - just bin the washer

The initial fit of the clutch had no contact to the bolts & the clutch is only worn down 0.1mm, so I wasnt expecting contact... ok the contact was worse due to the plate being the wrong way round, but even so it had contacted the bolts when it was the right way round...

Another lesson learned!

[turbonutter]

Ok so last week I got the engine back in the car with a new clutch. All good so far, the clutch is much nicer to use than it has been for a long time, so well worth changing it. Been out on the road for 100 miles now and no issues - no more cutting of the engine since I changed the overboost parameter, so I am happy again
I want to play with the boost control, so if the weather forecast is good I will be at Blyton on the 10th Oct...

[turbonutter]

Evoluzione said:

The large metal washer is used on quite a few Fiat group engines and has been for years, on the ones I have seen it holds the loose spigot in place.

I have temoved the washer, as on my engine its just a washer, its not serving any other purpose or holding anything in place...

[turbonutter]

Evoluzione said:

turbonutter said:

Evoluzione said:

The large metal washer is used on quite a few Fiat group engines and has been for years, on the ones I have seen it holds the loose spigot in place.

I have temoved the washer, as on my engine its just a washer, its not serving any other purpose or holding anything in place...

Yes I can see in your pic it doesn't do that, I do wonder why they fitted them though...

Talking to a guy that has done quite a bit of work on the Alfa V6 engines, he told me that some variants have the washer and some dont, but that there is no logic or method as to which ones or why they are fitted to a particular engine.

[turbonutter]

Ok decided against the track day on Saturday, the plan now is to do a proper test day next Tuesday. Much better than trying to test during a track day !

[turbonutter]

Well for a change I can post about a successful day at a track, rather than the usual disaster I seem to have been having recently.

Testing at Blyton on tuesday went really well, We had done some preliminary tweaks to the Boost control & Traction control before going & spent the day fine tuning both..

First off the track was wet, but that was ideal for testing the traction control, we started using Ignition retard & cut & fuel cut to reduce the torque, which worked well, but later added in DBW control for the torque as well, the DBW torque reduction worked really well, so that is now the first operate, with the Fuel and ignition cuts helping out if the slip gets to far off target. It works really well, nice and smooth & the cant feel it operating...

Boost control is also nicely setup now and follows the target wery well, and we set it so that the boost reduces as throttle reduces & also gear by gear.A big reduction in boost in first gear to look after the CV joints, the mid range boost increasing as you change to higher gears.

Many other tweaks were done during the day as well, including soring out the over run fuel, as it wasnt cutting propperly & producing huge flame... The flame is still there on gear change, but a much more subtle one, as seen below.



Overall I'm very happy with the results & the capabilities of the ECU and the way the car is running


Of course nothing is ever perfect & I see now that the Oil temperature is getting to hot 135-140C, so the laminova cooler is not eficient enough & one of my EGT sensors has failed, but thats not a big deal..

[turbonutter]

stevieturbo said:

Considering the work and changes, that all sounds very positive.

And leave that fuel cut the way it is

Thanks & Yes it is very positive, hopefully I can just drive the car for a while now

When we looked at the over run fuel cut, we had forgot to tick the box to activate it, hence when it all got nice and hot there was a HUGE flame, The flame you see in the photo above is with all fuel cut on the over run, but there is obviously enough left over somewhere to make a nice flame ;)

Just been looking at the Oil temperature that was logged & it maxed out at 126C, so there is a difference of 10C between the ECU sensor and my dash gauge - maybe it wasnt as bad as i thought...

Edited by turbonutter on Thursday 15th October 18:24

[turbonutter]

stevieturbo said:

I'd probably trust the ecu reading if it's using a proper 2 wire sensor, than some of the sensors you get with cheap temperature gauges ( not saying it is cheap...but a lot are lol )

But it would be handy if you could test the temp reading.

That said, the 130+ you mentioned did seem unusually high. I've never seen more than 110degC on my own since I started monitoring temps all this year

Its a KA Sensors NTC1 2 wire sensor (brand new) wired to the ECU 'vs' a Stack sensor and Gauge.. I am planning to test both sensors when I get chance, but its a bit of a pain to get at them.
Driving on the road today, the oil temp was max 106C (ecu temp)

[turbonutter]

Just a thought - both my sensors are measuring the oil temperature as it comes from the pump, so before the cooler. Is that the normal place to measure? Obviously it wont be so hot if measured after the cooler.
Where is the temperature measured normally????

[turbonutter]

stevieturbo said:

227bhp said:

A question for anyone on traction control; why not just lower the boost by opening the WG in certain gears? It seems yours is a very complex solution so there must be reasons for this.

Edited by 227bhp on Friday 16th October 14:38

In terms of traction control, altering boost as a reaction to traction loss is a very slow way to try and deal with it

Ignition, fuel or in this case also DBW, are much much faster.

But he is also using gear dependent boost ( among other parameters ) to try and give a power delivery that prevents traction loss in the first place, which ultimately is the best solution...however traction can vary so you could be leaving a lot on the table there by going too low.

You just beat me to the reply and summed it up very well.

As mentioned traction is dependent on many things like the road surface/ water and wit traveling straight or turning, so it is impossible to control just by targeting a certain boost in a particular gear....

Traction control is complex to say the least!

[turbonutter]

Max_Torque said:

turbonutter said:

You just beat me to the reply and summed it up very well.

As mentioned traction is dependent on many things like the road surface/ water and wit traveling straight or turning, so it is impossible to control just by targeting a certain boost in a particular gear....

Traction control is complex to say the least!

Modern road car traction control systems have a full physics dynamics model of the car, and have "adaptive friction compensation" that uses the engines Torque control strategy to feed forward a limit wheel torque that is estimated to reach peak friction. That value is then modifed by the real time closed loop controllers in order to further optimise the tractive effort curve!

Knocking a bit of spark out, or closing the throttle a bit isn't really "complex" by today's standards.......... ;-)

Agreed OEM stuff is extremely complex, my solution based on wheel slip & torque control using ign & fuel cut, ign retard & DBW throttle control isnt that complex, but a there is a lot more too it than just targeting less boost as mentioned

[turbonutter]

Max_Torque said:

turbonutter said:

Just been looking at the Oil temperature that was logged & it maxed out at 126C, so there is a difference of 10C between the ECU sensor and my dash gauge - maybe it wasnt as bad as i thought...

Std resistive 2 wire automotive temperature sensors are Negative Temperature Co-efficient (NTC) devices. This means there electrical resistance FALLS as their physical temperature increases. They follow a Log curve, where resitance halves each time temperature doubles, so once over about 100degC they will have a pretty low resistance (compared to their room temperature resistance) As a result various inaccuracies in the measurement systems (voltage offsets, resolution, calibration & reference errors etc) start to become dominant. For the vast majority of OEM sensing, you really only care about absolute accuracy and resolution at low temps (for cold starting/compensation etc) so this trade off is not too bad.


if you take a typical sensor:



a 1degC temp change at 20degC changes the sensors resistance by 1.3Kohm, but the same 1degC change at
110degC is just 40 Ohms.

OK Was working on the car today, so decided to test the oil temp sensors.....





Before the test with the sensors in air - Stack gauge was on minimum (40C) ECU sensor showed 15.5C
With some warm water in the can --------- stack gauge read 62C & ECU 53C
With the water heated to Boiling with a flame, so at 100C, Stack read 107C & ECU 99.2

So at 100C the gauge is over reading by 7% & the ECU is under by 0.8%.

Based on those errors:
When the stack gauge read 138C, temp was 128C
When the ECU read 126C, temp was 127C.

So although high, the temp is in my acceptable range.. There is an option with the Laminova cooler to insert a partial restrictor in the central bypass flow to increase the flow through the cooling channels, so that is something I could try easily...

Checking the oil pressure logs with the oil hot, it was 70psi @2500 rpm & 90psi at 6500rpm even at idle (1200rpm) it only dropped to 38psi. So all good there

[turbonutter]

stevieturbo said:

But lets face it...a lot of OEM traction control systems are ste and over aggressive, killing too much power, too often.

Sometimes complex isnt always great.

Mine is set up with dash selectable slip, and with 3mph slip target you can have a controlled slide in the corners..

I can choose between "OFF" and 1,2,3,4,5,6,7,8,9mph slip..

[turbonutter]

The stat opens at 75c temps on track were between 85 & 90c I don't think I could lower the temps without modifying the cooling system!

[turbonutter]

While I had the bean can out, I checked teh water temp sender.. both ECU and Stack were reading 5C high. This ECU sensor I wasnt 100% sure of the values I used, but at least now I know its correct & I know the dash gauges read high...

[turbonutter]

Just had a quick visit to the rolling road, to see where I am power wise now the boost control etc is sorted...

I am running 1bar as the max boost at the moment & ended up with 473BHP & 460lb/ft...



http://vid1086.photobucket.com/albums/j446/turbonu...

[turbonutter]

Max_Torque said:

Lovely wide spread of power between 5500 and 6500! Must be easy to drive fast ;-)

Its about 100BHP down on what I had before with 1.3bar boost, but TBH that was maybe too much. Its very nice to drive now, as we have the boost mapped v/s rpm, throttle & gear. In fact its better than before with the extra power.

Still thinking of going with a smaller turbo, to get it to spool faster, as on the RR we didnt hit the boost target until 4700rpm & on the road its 500-750 rpm later than that.

Thinking of a GT3076R, with a tial turbine housing, as that will fit to my existing exhaust & boost pipes etc with no modifications. Looking at the turbine flows, the 3076 1.06ar housing flows the same as my current housing, so shouldnt choke the engine any worse than now & so should spool faster and still give me 500BHP... This needs investigating though...

[turbonutter]

The engine is from the Alfa 147 GTA 3.2 V6. I am using the "stock" GTA cams, which i believe are slightly different to the non GTA 3.0l V6. The only other modification to the engine is the Low Compression pistons at about 8.4:1 ( i would have to dig through my files to find the exact C/R.

[turbonutter]

stevieturbo said:

turbonutter said:

Its about 100BHP down on what I had before with 1.3bar boost, but TBH that was maybe too much. Its very nice to drive now, as we have the boost mapped v/s rpm, throttle & gear. In fact its better than before with the extra power.

Still thinking of going with a smaller turbo, to get it to spool faster, as on the RR we didnt hit the boost target until 4700rpm & on the road its 500-750 rpm later than that.

Thinking of a GT3076R, with a tial turbine housing, as that will fit to my existing exhaust & boost pipes etc with no modifications. Looking at the turbine flows, the 3076 1.06ar housing flows the same as my current housing, so shouldnt choke the engine any worse than now & so should spool faster and still give me 500BHP... This needs investigating though...

IMO weld a fitting onto the manifold pre-turbo and see what pre-turbine pressure is like.

IMO there is no way it can be high or choking as you suggest, yet still spool so slowly, and when using relatively low boost.

I'm sure you've said before anyway, but what turbo and turbine housing are on it now ?

To be honest I dont know how much exhaust pressure is too much when compaed to the boost. I have Exhaust pressure logged, its a bit "noisy" & Ithink I need an orifice before the sensor, but it shows the pressure ok. from about 4500 rpm the exhaust pressure is greater than the boost & at the redline its about 70kpa above.

The data below is from the same pull on the rolling road that the power graph is from.. The Exhaust pressure is the same when on the road...




Turbo is a GT3582R with 0.82a/r turbine housing

Edited by turbonutter on Thursday 29th October 17:27

[turbonutter]

andygtt said:

unrelated to current questions... but do you run under piston oil squirters?

Yes - the Alfa engine has them as a standard fitment