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Old 08-05-2012, 11:46 AM   #8
2012ZL1
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Drives: '12 ZL1,67 Cam,68 Biscayne 427 4 sp
Join Date: Aug 2011
Location: B.C. Canada
Posts: 1,701
(IMHO) The only reason I see to keep them is that a hemisphrical reverse dome piston needs help promoting full combustion as a result of inadequate quench.
There is no quench pad on the piston, so the wing helps create turbulence in a "non turbulent" environment for proper homogenization of the fuel/air mixture.
If this is the case it is not wise to remove it,and port flow must be improved in other areas. Minor smoothing or blending of the wing is probably o.k., but the leading edge should be kept prominent.
Replacement pistons with a quench pad could be used with wing removal.
The theoretical reason for non quench pistons in a supercharged environment is to remove detonation or hot spots which can happen on the piston.
In hyperutectic pistons, a hot spot is what causes failure from what I've read. Idealy, a hemisperical combustion chamber would be perfect, but since the engine design does not allow this, the next best thing is a reverse hemisphere piston.
Now the lack of turbulence from the piston needs help, and help is in the form of the wing. The wing keeps the "turbulence generator" out of the actual combustion chamber, which should lessen the chance of hot spots, and let the piston live, and allow more timing etc.

This effect only happens on after supercharger fuel injected engines, because in traditional carburated roots set ups the fuel comes in pre- blower so the blower does all the homoganization of the mixture.

In supercharged engines that fuel is added "after" the blower such as this, the fuel does not have the benefit of the blower mixing it into the air.
You need something in the arrangement to do the mixing of the two post injection site. That leaves the bowl area or the combustion chamber. For the reasons I mentioned above the chamber is out, so that leaves the bowl area.
Its not that it won't work without it it's just more efficient with the homoginizer in the mix.
Now the question remains that at more aggresive cam profiles and raised rpm ranges, will the wing be needed, and will it be a detrement to power once those variables are changed.

This is just my guess from what I've seen of the parts,and general experience with blowers, but if I'm wrong anyone can feel free to call me stupid. Heck call me stupid anyway I don't mind..lol
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2012 ZL1
2.55 upper, 10" lower pullies, Innovators west billet hub and sfi balancer, solid blower drive isolator, 50 mm idler kit, full length S/S headers no cats, comp cams custom grind cam, comp roller rocker trunion kit, comp push rods,dual valve springs retainers and locks, Injector dynamics ID850 inectors, Rotofab ZL1 cold air kit, Lingenfelter 160 thermostat, Rotofab intercooler reservoir, stock plugs, LS7 90mm throttle body, GTO clutch reservoir mod, my own custom catch can, Tuning by Jannetty, install by me.

Last edited by 2012ZL1; 08-05-2012 at 12:04 PM.
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