Waarom hebben ze het eigenlijk nog over 240 pk?
Ik heb een thread gezien dat door het verplaatsen van de charge-cooler nog eens 20 pk gewonnen is.
Vind die Thorney trouwens niet erg betrouwbaar overkomen.
Kan zelf nog niets bieden, maar wel anderen afkraken...
S/C versus trottlebodies
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SteV6
- Mega lid in de orde van gouden nietje
- Berichten: 2473
- Lid geworden op: 02 dec 2004 20:22
- Locatie: Twente
SteV6MAP18W,Mar 15 2006, 18:39 schreef:You're right in that running an engine lean can cause damage, however the S/C conversion does not run lean, due to the on boost fuelling. Retaining the standard ecu on the S/C conversion retaines all the safety functions built in by the manufactuer including knock control and also its ability to close the throttle to prevent internal damage should the ecu see something it really doesn't like. Between us and Hitec we have over 25 cars out there. One of which has now covered over 100,000 km. Furthermore Chris Vogler's car does nothing but spend its life around Hockenheim and the Ring with no durability issues.markv,Mar 14 2006, 21:14 schreef:BTW, on the reliability part. I guess with tuned engines that run under forced induction, it is trickier to get them as reliable as a tuned NA. The effects of running the engine lean under forced induction are much worse than with NA, which is a frequent killer with engines I've seen..
The downside of getting more power out of an NA is usually running more revs. More revs are usually ok up to a point (most that I've seen take 7200 without problems). If you go higher you usually need to make some changes, or the reliability of the engine will go down.
If John gets the power from the NA without gonig over the 7200, I would guess that a NA TB setup will be more reliable then a compressor setup. If I have understood correctly the compressor uses an add-on computer besides the standard ECU to get things running correctly. Personnly I don't like that. Without knowing all the details, it sounds like a workaround for some problem running the car with only the standaard ECU. Judging from the GM documentation on the compressor add-on for the 2.2 it isn't needed, they remap (or maybe use new software) to run the compressor with the standard ECU.
Then again, I guess the 2.2 is pretty strong, so I don't know if you really will notice the difference. Only one way to find out, try it
Mark
As you say the downside of getting more power from an NA is to run more revs. This is why we rev limit the Stage 2 S/C conversion to 6,500 rpm. If you look at the power graphs you will see the engine is still making power when the rev limit is hit at 6,500 rpm, more power is available between 6,500-7000 rpm however in the interest of durability we won't let the Stage 2 rev higher than 6,500rpm, and we are making over 240bhp at this point. Paulcp has had to have a shift light fitted due to constant hitting of the rev limiter due to the speed the car get there!
The Stage 3, under development, which uses more internal component changes for further durability and reliability and will run to 7,000 rpm or so and current testing is producing in excess of 260 bhp.
Referring back to the SAE Paper on the turbocharged engine all the components are well within durability. As previously mentioned the Stage 2 S/C conversion runs to 6,500rpm specifically for durability and reliability. We will only run past 6,500 rpm on the S/C conversion with additional internal mods so that we do not compromise durability or reliability, but when we do will will again get a power increase into the bargain.
As for the piggy back ecu to control the fuelling....... Yes without a doubt it would be good to use the GM/Siemans ecu to do the whole job. However this would require a complete re-calibration of firmware and software required for bigger injectors and also to change from the 1 bar map range to run to 2 bar map range. To do the firmware change I would suggest you would either need to be GM or Siemans to be able to come up with the budget to do it. Furthermore if it were done this way it would again increase the cost of the conversion to a point where it would start to become unviable. This is why in the aftermarket nearly everywhere uses a piggy back ecu to achieve its required results. Retaining the standard ecu ensures that off boost driveability, emissions etc are as standard with the piggy back ecu controlling the signalling for the correct fuelling to meet the demands of the conversion on boost. We have been turbocharging Vauxhall engines since the early 80's, long before Vauxhall introduced a turboocharged engine into their range and have used piggy back ecu's to cope with the demands of on boost fuelling with no ill effects along with many other tuner's out there in the UK, europe and Japan.
I have to agree that TB's sound great on an NA car, and have driven many 2.0 engined cars on TB conversions. I also have to say that the S/C converted cars are fabulous in the way they deliver their power.
S4 Avant
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SteV6
- Mega lid in de orde van gouden nietje
- Berichten: 2473
- Lid geworden op: 02 dec 2004 20:22
- Locatie: Twente
De push vanaf lage toerentallen van een mechanische compressor spreekt mij nog steeds erg aan (vanwege mijn voorkeur voor het gezegde: "There is no substitute for cubic inches"), maar het karakter van een TB-conversie en met name de bijbehorende sound is ook niet te versmaden.Maik schreef:En slaat jouw metertje nog steeds over naar de SC conversie, of naar de TB's Stephan?
Tot op heden is er relatief veel ervaring opgebouwd met de HiTec-kit. Meer dan 25 auto's, continue doorontwikkeling met bijbehorende voordelen enz. enz.
Bij de TB-kit van Thorney is het nog even afwachten over het hoe wat en hoeveel 't uiteindelijk gaat kosten.
Kortom het dubbeltje staat voorlopig nog even op z'n kant.
SteV6
S4 Avant
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