What boost do you run?

[George Elliott]

Tom
1.2 Bar on present car, and also previous Promax L2 kit car.

Present car has K&N Filter, derestricted snorkle, Lindsay Stg 1 I/C, Std Head & Cam, BB Garrett/KKK hybrid, 3inch DP, 3inch exhaust.
My feeling is, if the cam was right, and the Agricultural ECU was improved, there is scope for better drivability and more power.

Ultimately, the open deck block was the downfall of the Le Mans 944 engine unit at high boost, and I would be careful above 1.2. Interesting Mark's car runs 1.5, I think it showed 400 when Promax did it which is impressive, but the Intake manifold was credited with much of how the boost was managed to give more power?
The tuners in the States seem to use big boost

One psi = 10 bhp.......to a point.[

George
944t

 

[MarkK]

Oulton Park,it's a a PCGB day a few drivers from the Championship are going I think,I am only floating around,road tyres incase the weather starts something ugly[]

 

[barks944]

Annoyingly I have lost my EGT kit, which means I the ECU won't be able to measure that for the dyno runs Should have time to fit the wasted spark system to the car though and the ECU is reading the AFR via my wideband.

 

[barks944]

ORIGINAL: George Elliott

Ultimately, the open deck block was the downfall of the Le Mans 944 engine unit at high boost, and I would be careful above 1.2. Interesting Mark's car runs 1.5, I think it showed 400 when Promax did it which is impressive, but the Intake manifold was credited with much of how the boost was managed to give more power?
The tuners in the States seem to use big boost

I guess its ultimately about duty. I can easily vary the boost pressure, or have the ECU do it based on what the driver is doing how hot the engine is, EGT's etc. I'm also quite looking forward to playing with the ignition advance in closed loop. Now that the DME can read knock events I am much more comfortable running the engine closer to its limit.

 

[TTM]

ORIGINAL: George Elliott
Interesting Mark's car runs 1.5, I think it showed 400 when Promax did it which is impressive, but the Intake manifold was credited with much of how the boost was managed to give more power?

I'm sure the intake helped a lot. The Lindsey S75 turbo has a huge compressor wheel. Coupled to a replica KKK #10 turbine on Mark's car, it must build a pretty high amount of exhaust back pressure. I'm sure it could make even more power, but that would need a less restrictive turbine, which would greatly affect the spool given how huge and heavy the compressor wheel already is.

 

[Diver944]

Marks car has always been amazingly reliable and I have to admit when I first saw the dyno sheets at our Rolling Road day I thought it would never last long at 1.5 bar boost []. It has proved us all wrong and shown that with the correct combination of parts, Promax have built one of the longest lasting 400+ cars in the country [8D]

 

[MarkK]

Had a fun day today at Oulton,car went well was a bit greasy earlier on but dried as the day progressed,hysterical fun[]

 

[barks944]

Yesterday I was on the dyno at Bob Watson Engineering here in the UK, Bob is a very well respected independant specialist. I selected him for his experience and vast knowledge of tuning. We spent about 2 hours on the dyno on UK rating 95 octane (Standard pump fuel here), my road tune was quite close and made 286FWBHP at 1 Bar, this progressed to a little over 300FWHP with some slight ignition and fuelling tweaks while we were there. Again still at 1Bar boost. We moved to 1.2 Bar and although the torque increased it was clear that the #6 turbine would not flow any more and no more power was gained. There will be more power from further tuning of fuelling and ignition but I want to wait until my DME has knock and EGT fed into it from the KLR so I can properly handle knock events and really run the engine close to its limit. I suspect >320 FWHP would be achievable at 1Bar. I also need to fit the wasted spark kit and I was not happy with the boost control (manual) so I will be installing my DME electronic boost control kit very shortly. All in all I am very pleased with the result >350NM is available from 3000-6000rpm which I think is great and the throttle/boost response is fantastic the car is quick but also very controllable, you can easily hold it on the threshold of boost in the corners. I can't wait to get all the additional kit installed and push it to its limits. I scanned the dyno sheets but they are rather poor quality.

https://picasaweb.google.com/113015926985862247896/944TurboDynoStage1?authuser=0&authkey=Gv1sRgCNThz-b235GJ5wE&feat=directlink

Data Log: https://sites.google.com/site/tomsite1234/files/944%20Turbo%20on%20Dyno%2015.11.2012.csv?attredirects=0&d=1

 

[barks944]

Just noticed the IAT's while on the dyno peaking at 62 degrees C!! There really wasn't much air flow through the intercooler I don't think. Doesn't get above 22/23 on the road! That can't have helped, at least it did not detonate! Wish I had noticed that, would have whipped the badge panel off to make sure there was some flow across it.

Edit: Air density at 20C is 1.2kg/m3, at 62C it is 1.05Kg/m3. That's only 87.5% of what it should be at that pressure. To my mind that probably means a big drop in power? I think I need to go back and do that again....

 

[TTM]

Where do you have the IAT sensor? If in the intake manifold then 62°C while leaving the engine idling (=TPS 0%) for long minutes isn't too surprising, though still a bit too high I think.

Did you have any kind of huge fan in front of the car?

 

[barks944]

The IAT is in the manifold. This isn't 62C while idling its 62C while on boost! There was a fan but I don't think it was generating any flow through the IC. It's never that high on the road. You can see the IAT rising through the power run. At 5200rpm @ 1.2 Bar its 62C [&:]

 

[barks944]

Definitely not what I wanted to see!

 

[TTM]

Where in the intake manifold exactly? I have mine just behind the butterfly.

62°C under full boost is so high it just doesn't sound right. Are you sure about the sensor calibration?

The standard IC is said to soak heat after repeated runs, but that much...?
You really have to get some air flown through the IC otherwise it won't cool down compressed air at all.

 

[barks944]

It's right behind the throttle butterfly in the intake manifold. Like I say it's never that high on the road, nothing close..... 23C Max. I really don't think there was any air going through the IC. The IAT sensor is a standard bosch curve I believe and even if it isn't bang on accurate you can see from the curve that its increasing rapidly. You just don't get that on the road. The fan was pretty weedy and maybe it was just at the wrong angle to get any flow through the IC.

 

[barks944]

Here's last night on the road, 3 pulls successively at 1.2 Bar - 23C maximum.

 

[TTM]

23°C is better At what ambiant temp?

 

[barks944]

Probably about 16C. Unless there is something funny going on it looks to me like those intake air temps were real? Would the engine make any power if it was inducting air at that temperature?

The other option is that the sensor got heat soaked from the turbo. But the element is extended on two thin wires and is in the air stream so I can't see with the amount of air going through the system at full bore that it wouldn't be able to cool it down. I'm also surprised this doesn't happen out on the road. Although maybe there is better airflow and the load conditions aren't as extreme. I know a good hill, perhaps a good thing to do is try and hold it in a high gear for some duration as we go up that hill and see what happens .

 

[TTM]

I would question the accuracy of the dyno. 300 FWHP is impossible with a K26/6.

 

[barks944]

It's a hybrid, it has a bigger compressor wheel but the same turbine as a K26/6. The difference is it holds ~1.2Bar of boost to the redline but spools about the same.

K26/6 Hybrid
55lbs Injectors
2.5" Exhaust
Modifed DME
Mildly Ported Head
Standard CAM

Tom

 

[TTM]

Oh I see. It would be interesting now to measure exhaust back pressure to figure out how the superior flow of your different compressor makes its way through the turbine.