jim morehouse

Chris,
don't know if this showed up anywhere before but found the link on Phil's BB. Is this where you're heading?

Jim

<a href="http://www.bilinfo.dk/porschecentrum/showcars2.asp" target="_blank">big scoop</a>

Jay Wellwood

Gawd....I hope not (based on the 911 the link took me to).

bcdavis

Yeah... Bad link.

jim morehouse

just saw a message that the link was changed. It's now:

<a href="http://www.bilinfo.dk/porschecentrum/showpics.asp?id=162100105" target="_blank">scooped</a>

Jim

bcdavis

I think the interesting thing this car's engine shows, is that you can completely redo the intake system, with other kinds of EFI, or carbs, or whatever, so long as you run an aftermarket engine management computer. Or maybe the stock one would be able to compensate.



Regardless, all the people with the supercharger ideas might want to think about creating a system where the air/fuel metering takes place *before* the blower, as it is done on other race cars. Instead of trying to stuff compressed air into a stock intake system that was not designed for that much flow.

Something like this, perhaps?

jim morehouse

if you place the metering before the blower, isn't it less accurate because you're not measuring the temp of the air entering the intake and therefore the mass? I don't know a lot about this but always thought that if the metering system had the range and could stay linear over the mass moved by the supercharger then putting it after the blower would result in more accurate measurement. Don't you lose some accuracy if you put it before or can you assume a more or less fixed rise in temp due to the blower and compensate for it?

Jim

Chris Lockhart

Hey Jim. Pretty wild looking 928, huh?? Not quite the hood direction I've taken. I think mine looks alot better, although it's not really functional at the moment. My cold air induction set-up didn't pan out. Even though I was using a 4" pipe, the system was too restrictive for abrupt throttle transitions. Pipe couldn't feed the immediate volume of air that the engine needed, at least not like the stock airbox can. I believe the airbox is 11 liters, and my pipe was only about 3 liters. Still have a few other things in the planning stages though. Hood still looks cool though. At least to me. LOL. Still have yet to get it painted. I guess I'm a true southern redneck with a primered hood. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

bcdavis

Well, obviously, you can do it both ways.
But I think the reason we put the blower in front of the fuel injectors, and before the intake manifold, is because with the small blowers we mount in the front of the 928, there is no real option to do it the other way. But the way it has been done for years, is with the injectors, or carbs, on *top* of the blower.



If putting the carbs or fuel injectors under the blower worked better, I am guessing drag racers would have done it.

????

Both ways seem to work. But I am guessing you can dump a lot more air and fuel into the blower using the old-fashioned setup.