RS2 GT3071R dyno results

[monstereddie]

@monstereddie

the car jamo says it made 428 is like mine with the following differences:

1) 7A exhaust cam
2) OEM pistons
3)OEM exhaust system
4)OEM exhaust manifold
5)RS2 intercooler
6)S2 intake manifold
7)Remap by mihnea reaching 1.9-2bar and good EGTs as Mihnea stated

see now why im thinking that i should have around 400hp @flywheel (or 350@ wheels at least) in order to make this power?It is impossible to have 358hp flywheel as maha suggests.

I also believe, that the guy did a mistake on the measure. We calibrate the mass on any car. It is very important to do this right!

[EspenW]

I also believe, that the guy did a mistake on the measure. We calibrate the mass on any car. It is very important to do this right!

I know that also Mustang dynos take vehicle mass as an input. I suppose that is to generate the correct resistance curve for a sweep (inertia mode) test. Do you also program wheel weight and moments of inertia for the wheels?
If not, this will affect the outcome as heavy/high inertia wheels will slow the acceleration on the dyno, thus making the power seem lower than with light wheels. On the coastdown, the heavy wheels will trick the computer into believing that resistance is lower, since the inertia of the wheels will cause the drivetrain to slow down slower. Thus: less power measured on the way "up", and less resistance measured on the way "down". End result is that heavy wheels will show a significant power loss vs lightweight wheels on an inertia type dyno, especially when performing a (highly flawed) unloaded coastdown test after the power run.

[prosty]

No worries about the attack. Just don't think of me as Poland .

I've seen several cars with atleast "450 hp" with Rs2 EM, For instance an S2 coupe with RS2 EM and 186 kph top speed in the Quartermile, with 17" wheels and full weight. This is according to quarter mile calculators around 400 hp on the wheels.

But I must check if I actually know any 500 hp cars with RS2 EM, I can be mistaken about this. But this has to do with backpressure too if you want to go higher on the power scale, flow wise it should suffice for 500 hp, but not as good as a tubular one would, so the EM would be a restrictor powerwise. But with a big exh housing it's doable imo.

Just talked to a friend who tunes these cars, he sais 450-500 is doable (he has tuned a few cars to this powerlevel ) but over 500 is not recommended due to backpressure issues. Then the SPQ EM or a tubular one would be better. So I was right & wrong, I would not use an RS2 for these powerlevels

Little more research done anyway.

[monstereddie]

@prosty:

we do not have to forget, that i am always talking about 500 horse powers on the wheel! I mean DIN measured. If the Engine delivers 500hp on the crank, i can not tell and i can not imagine, cause i never tested it. I had a S2 weeks ago with 414hp on the wheel. I don´t know how much this would be on the crank.

The maximum i ever reached with the OEM RS2 Exhaust Manifold on a dyno DIN measured was 404hp with a KKK26/27/29.6 at Sportec in Switzerland by the customer. The result diagram must be somewhere.

[prosty]

Okay I was talking about crank HP

[A80Avant]

@monstereddie:if you have with your calculations 330hp at the wheels,then how much crank hp would it have?

[aronmatic2]

@monstereddie:if you have with your calculations 330hp at the wheels,then how much crank hp would it have?

400

[Ross]

I also believe, that the guy did a mistake on the measure. We calibrate the mass on any car. It is very important to do this right!

Just to clarify, my car had:

3B ignition
3B IM
RS2 EM
3" single-backbox
GT3071R
RS2 IC
#2 oversize bore pistons, mahle i think
7A exhaust cam
Mihnea map @ 2.0bar

Map wasn't complete, but mihnea got her running well and dyno'd 428 @ the crank. Plenty of other S2's there pulling hte correct figures to prove the dyno wasn't off...

Ross

[A80Avant]

oh ok then!Best guess then is that my crank hp is a little higher than 400 cause i had 334 on 1.5bar.Now im at 1.7bar!

if there are changes to be made,they will probably include a cyl.head treatment as well,cause it helps a lot! especially since i dont want to go with the wagner inlet manifold yet as i like the cruise control very much!

[A80Avant]

so ross,3inch single backbox means,no cats and 1 silencer?

and on what type of dyno did you measure it?It seems odd to me that the exhaust catback,the cats, and the 7A exhaust cam can give almost 100hp more @the wheels!!!

[Bram]

Just to clarify, my car had:

3B ignition
3B IM
RS2 EM
3" single-backbox
GT3071R
RS2 IC
#2 oversize bore pistons, mahle i think
7A exhaust cam
Mihnea map @ 2.0bar

Map wasn't complete, but mihnea got her running well and dyno'd 428 @ the wheels. Plenty of other S2's there pulling hte correct figures to prove the dyno wasn't off...

Ross

I am impressed with 428HP at the wheels with a RS2 EM & RS2 IC. This would mean something like 500 HP at the crank?

[Ross]

Sorry, I need to edit the post - 428bhp @ the crank

It felt like 428 at the wheels going 0-150 up a damn steep hill tho. On a test-track

[A80Avant]

that's what im thinking as well!
i always thought 428 was crank hp not wheel hp,also because all turbo shops advertising the GT3071R turbo have it for crank hp no more than 475hp!!!

I also know that garrett usually understimates it's turbos but....it still is a bit comfusing now..

***EDIT***Ross got me to the edit!!!

***EDIT 2*** If we manage to get together sometime you can see if my car feels like yours or much less.Only thing is im still far from you although in the UK!

[Ross]

LOL, yeah. I'm India at the mo working, think we come pretty close to Greece on the way home! My wife would love to visit Greece tho so maybe one day...

Also to say - yes, no cats on that exhaust, it was pretty free-flowing. Turbo-back as well. The car felt phenominal, it was such a jump over the ~300bhp I was used to!

Also - we turned up the boost in increments, at 1.6bar it felt quick. But 2.0 bar was in a whole new league of fast. So if you're running 1.7bar then I would suspect 400bhp crank is pretty good. Turn it up to 2.0 and I suspect it'll be nuts. I was still on 1.8bar @ 7,400rpm redline. Plus, I was on 99RON Vpower.

[Bram]

LOL, yeah. I'm India at the mo working, think we come pretty close to Greece on the way home! My wife would love to visit Greece tho so maybe one day...

Also to say - yes, no cats on that exhaust, it was pretty free-flowing. Turbo-back as well. The car felt phenominal, it was such a jump over the ~300bhp I was used to!

Also - we turned up the boost in increments, at 1.6bar it felt quick. But 2.0 bar was in a whole new league of fast. So if you're running 1.7bar then I would suspect 400bhp crank is pretty good. Turn it up to 2.0 and I suspect it'll be nuts. I was still on 1.8bar @ 7,400rpm redline. Plus, I was on 99RON Vpower.

I get confused by all the excitement time to time as well Ross

Currently I have 1.8 bar at 7200 and 2.0 bar between 5500-6500 rpm. However I am still not really impressed by the performance, so I think I need to swap to a 7A exhaust cam and a bigger IC (now running a RS2 IC) to get further above the 400 HP. I think currently I am around 400, but in June we will have a Superflow session with our s2power forum to get real numbers.

Do you think the RS2 IC limited your setup, or what outside temps did you have when doing the 428HP run?