Arouse the DAMPFHAMMER!
I did ask Mahle about this, they don't release a further cutting of 1.0-1.2 mm in their pistons because of safety issues. A 50° capability would be great as significant torque increase comes with it. The DAMPFHAMMER engine is designed to love it, because it is an NA VE border riding engine design, but safety comes first.Why did you not modify the pistons for more clearance or is the extra cam angle not needed anyway with this setup?
Duration aren't the right measurement to rate the VTC, it's the centerline and the steepness of the valve lift gradient after the valve lash. Take a DC 3.2, which has roughly the same duration, but is likely able to run 6°-8° more.I'm surprised they sell a piston that is designed for performance builds that does not allow this, its not as if the A3 is a big cam.
Stability of the piston crone and the combustion efficiency/duration. Also having bigger or higher edges beside the valve reliefs = more knock. All calculations and simulations are done on the actual capability of VTC. It's still ok .Also very surprised you compromised on this as maximum VE over the widest range was the whole point of the build.
You can make guess out of competition as the guessing game had unfortionally a deadline for guesses. Out of the competition you can do a guess.Looking good! Have you got a complete list of engine mods so I can have a guess? ; )
Hopefully this link works:So it were ITB's with an EFI system they use there?
Thanks for the pictures Scider! I read about the approaches in a SAE paper about using non-spreading-spray pattern to increase the VE and the cooling capacity. But for this you need fuel with a low evaporation temperature and low specific heat capacity to get it properly mixed in the chamber. Alcohols and other stuff like Hydrazin are perfect partners for this approach. I run pump fuel, so I have to go a bit a different route for the best compromise on those two counter fighting parameters.This is a set of ITBs for the GM Indycar circa 2002. The big hole in the side was actually where an injector block would get bolted in and would direct fuel flow into the left and right ports as well as up the velocity stack. One injector was used on the top of the injector block. It didn't have a spray pattern, more like a laser to shoot liquid methanol into the cylinders. At an AFR of 4:1 if the fuel didn't evaporate it would be enough to hydro-lock the engine
For your interest, Lotus told me the CP pistons with extra deep valve pockets feature have 3 mm PtV clearance on his 93 mm stroke engine. If the piston deck height is the same, it should also apply to the 86 mm stroke engine. But these pistons are low silicone content Alu alloy's, not like the 4032 alloy of Mahle, having a lower thermal expansion coefficient. Maybe Lotus can chime in and report about the eventual noise he can here at lower loads with the CP's?Also very surprised you compromised on this as maximum VE over the widest range was the whole point of the build.
Oh sorry for wrong remembering. Concerning the technology transfer Supertech states on their website: "Supertech pistons are manufactured in Argentina with technology transferred from European manufacturers.". Who know what it include.Markus, my pistons are from supertech, not CP.
They are mode from a 4032 type of alloy. I once even heard the forging slugs are supplied by Mahle, but I am not sure.
I run a similar piston to bore clearance with my 4032 alloy Mahle piston too. Good to know they don't slack around .I run a nominal 80µm piston to bore clearance with them and have no hearable noise during cold operation.
Nominal as the centre of the bore has closer to 100µm cold clearance.
The reason is that during honing (with a honing brace) focus was on roundness, not absolute diameter. Rings seal better in round bores.
In the middle, it took a tad more to get them round.
I saw your post on FB, hard to believe it will only decrease oil temps by 3 deg, be good to see some actual results on the setup, maybe join the oil lines together and do a before and afterFluid system:
Upgraded the pump an the cooler to CWA400 and ECD54-182 because of specification and safety reasons. Some reports about the C43-182 use for racing and the still guessed oil flow flux of the K20A2 oil pump over pressure made me deciding for it. That means doubling flow and pressure capability of the pump, doubling of rated heat flux from oil to cooler and less than half of pressure drops on oil and water side. It was an expensive decision, but better than replacing it later. An indication for oil flux I found a few days ago on K20a.org, stating it is according the RSX manual 54 l/[email protected] rpm...maybe flow without pressure.
Sensors sent to welder. The E-technician is briefed and have all the sensor harness informations (flow schematics, sensor list, control functions, ...) he need. Need to get an arrangement of the mechanic stuff finish due date to start the harness stuff.
Sure I will test it t3gav . What I've shown there is following setup:I saw your post on FB, hard to believe it will only decrease oil temps by 3 deg, be good to see some actual results on the setup, maybe join the oil lines together and do a before and after
Thanks Lotus. From the available data, I also get the impression of it is just the back pressure less volume flux. Maybe stated in the manual for test reasons, filling up cans to check the flow rate....They 54 l/min may be what the pump pumps, but not what is actually flowing through the engine.