RS2 GT3071R dyno results

[A80Avant]

i thought of creating a new post so as to have comments solely on the power figures.
Car is with GT3071R turbo,custom intercooler,OEM inlet and exhaust manifold,downpipe 80mm,twin cats,70mm cat back with 2 resonators.

The remap was done to reach 1.9bar overboost and 1.5 steady boost,figures that where somewhat achieved on the dyno(1.85 and 1.5 i think) and the results came as you see from the photos.
There is a little surge i would like to tweek into avoiding.What do you think can be done?

Overall,do you think that having more red line boost will give anything more that would be in the safe area?I know the turbo can take it,but i dont know what the EM will have to say and the EGTs as well.Is it worth it?
The place i went said that on high revs the lambda factor goes quite on the rich side,sometimes being 0.7(i dont know how low this is comparing with the λ=1 which is the perfect mixture).

comments and thoughts are most welcome!!!

[A80Avant]

here is the curve as well.

dyno was a rototest hub dyno and from what i managed to find out,the wheel power it measures is usually higher than the wheel power the maha measures.But i couldnt find any 4wheel drive data from both dynos to compare.I may have to go on a maha again to see the results,but i think on a maha it must produce around 395hp crank or so...

[aronmatic2]

nice results. its can be very fun to drive
the lambda 0.7 is very rich, but if your sparkplugs dose not say anything, it can go.
its safe.
congratulation for the car and be carefull on the slipery road with this power.

[Bram]

When it is running that rich it could produce a bit more HP when correct mapping is done I think. 450 crank HP is possible with this turbo.

[S2central.net]

WIthout doing the maths, I'd also say that is too rich... You want AFR in the range of 10-12 at WOT - I feel you are richer than that - better that than being too lean - unless the plugs get fouled up (unlikely).

I suggest you get EGT and wideband AFR meters installed and see how that looks and use that as the guide for the next mapping session so that the fuelling can be safely reduced. This will lean out the mixture a little, give you more power and save some money Probably only needs a tweak in the WOT map(s).

The unevenness in the outputs (power follows torque along with RPM factor of course) are probably a result of too much advance at full boost - suggest that is dialled out as well quite easily.

Agree that 400-450 flywheel is possible here with a good setup. I reckon 450 is the max capability of the RS2 EM anyway.

Paul

[A80Avant]

wideband was used for the map,and i have EGT sensor.The egt on the dyno showed around 890C which is on the turbo hotside.On the previous setup it would go up to 920C.

The only thing that i was told is that i could get away with even 1.8boost at the red line and still be very very safe with this turbo and internal parts i have used.My concern though is the EGTs on this manifold.I mean if i have 890C now on this rich setup,then how will this cope with the 1.8bar???

Also i was thinking that maybe im having higher EGTs and richer mixture is needed due to higher compression ratio?i dunno.

BUT since i will be ultimetly coming to the UK at some point,i hope i will be able to have brought with me the wagner manifold,pay a visit to MRC and tweek everything accordingly so as to have the best results.

I believe Erdal has done a very nice job on the remap.If i had done this in greece,using the N75 valve would be impossible as i realised,noone can tune the car here with the N75 connected,as they dont have the equipment.Everyone is useing either electronic or mechanical boost controllers...

[S2central.net]

Feel free to play with this paper exercise... Some guesstimation involved of course as I don't know real world efficiency values for the GT3071R and RS2 intercooler.

Use the comments at each step to help you change any coloured cells.

I have three calculations for estimating power - I take an average estimate as the prediction but one of those is heavily swayed by fuel usage such that if you make things more rich it assumes you are making effective us of that fuel but its not that simple. I wouldn't go any richer than 10.

My initial boost values in this spreadsheet stay pretty close to surge line I have for GT30R - suggest you double check these and plot for yourself.

Paul

[S2central.net]

Based on map info I have, YES you would be OK at 1.8bar at 7500rpm - actually you could squeeze to 1.9bar and still remain within choke line - little close maybe and less efficient for sure.

I've attached another version showing this...

wideband was used for the map,and i have EGT sensor.The egt on the dyno showed around 890C which is on the turbo hotside.On the previous setup it would go up to 920C.

The only thing that i was told is that i could get away with even 1.8boost at the red line and still be very very safe with this turbo and internal parts i have used.My concern though is the EGTs on this manifold.I mean if i have 890C now on this rich setup,then how will this cope with the 1.8bar???

Also i was thinking that maybe im having higher EGTs and richer mixture is needed due to higher compression ratio?i dunno.

BUT since i will be ultimetly coming to the UK at some point,i hope i will be able to have brought with me the wagner manifold,pay a visit to MRC and tweek everything accordingly so as to have the best results.

I believe Erdal has done a very nice job on the remap.If i had done this in greece,using the N75 valve would be impossible as i realised,noone can tune the car here with the N75 connected,as they dont have the equipment.Everyone is useing either electronic or mechanical boost controllers...

[S2central.net]

Meant to add - those EGTs are quite hot alright - certainly for K24 or RS2 turbo I would be concerned. You'd need to get expert input from Garrett gurus about the max EGT that can sustain. Add about 100 celsius to the EGT measured after turbo for what is there before it - approx !

Paul

[A80Avant]

well Erdal pointed out that since my EGT sensor is actually ON the hotside of the turbo,the 900C figure is OK for EGTs.If it were placed anywhere on the downpipe not further than 5cm from the turbo hotisde exit,it then should read 100C lower to get the correct readings.
Making it a bit on the rich side was done mainly to be safe,as the 98octane sold here in Greece is not always true 98,and most of the times it is mixed with regular fuel for profit issues of the gas stations.Unfortunatelly it is a big problem here in Greece and even using BP or SHELL which is way over the top in prices it is still an issue of whether the fuel you are paying is actually ok.

Im afraid there is nothing we can do about that.
what problem would the rich mixture create on the spark plugs??

[S2central.net]

I think you have some margin then to go less rich... Though I totally appreciate the safety margin if you have fuel issues. In Ireland (NOrth or SOuth) its almost impossible to get anything better than 95RON - I hate that.

[A80Avant]

how about Newcastle????

[S2central.net]

Newcastle Upon Tyne = OK for 98 RON (why-eye man)

Newcastle in N.Ireland = 95 RON only (whats yer prablem wee lad)

Newcastle in Australia = no idea possum

[A80Avant]

LOL
yeah i meant to say Newcastel Upon Tyne.
if i will be coming to the UK that will be my first location i guess.Hopefully driving to Newcastle after newyears...so on the way down,maybe a stop at outside Oxford should be scheduled!!

[Faheemo]

I've posted my G-tech dyno plot on the forum before.
Fuel used for this dyno run was 95 Octane.
When using the correction factor for 4wd you get peak of +- 460 hp for my car. (hp+10 /.82)
I used a tubular manifold and 7a ex cam. std intercooler.
my AFR was in the low 12's.
Boost was 1.8bar peak and 1.3bar at the red line.
Ive run a higher boost file but only for 102 octane petrol and dont have a Gtech run.