Bob, Good point, however, in an automotive induction system, the point of lowest pressure is actually the point where all the air is exiting the system- the inlet runners. In a system of constant volume, the pressure would be double, as the number of molecules would double due to two pumps instead of one (ideal gas law: PV=nRT) However this only applies to closed systems, so in this case where there is a pressure drop in the system (the throttlebody) the best explanation I can come up with (since I don't have a physics degree) is to approximate it somewhere between the same pressure and double the pressure! Things like turbo efficiency and dynamics would come into it.. so twin turbos on 10psi each at constant rpm would be about 16psi....or something... I think....!
- Tom Bob wrote: >I think you would find that the pressure from the turbos is not going >to add together to give twice the boost. If this were the case, in the >piping leading from each of the turbos you would see 10psi, and in the >plenum you would see 20psi. Liquids/gasses always try to flow from >high pressure to low pressure points, so the air would then be trying >to flow back from the plenum to the turbos if that were the case. > >As I understand it there are basically two types of twin turbo setups >used on cars, one where you have two smaller turbos of the same size >which should spool up identically etc and not have the syncronisation >problem, which allows you to use small turbos to get less lag without >as much restriction at the top end, and the second type like on late >model 13Bs where it has a small turbo to cover the bottom end, and a >big turbo for the top end. I read a report once where the engineers >were commenting on the setup of it, apparently its a real bitch to get >right. > >Saturday, July 27, 2002, 12:00:19 PM, you wrote: > >DA> Ummm, correct me if i'm wrong Mark, but the only time one turbo shitting >DA> itself would cause diff intake into those two cylinders would be if you >DA> were running two separate intake manifolds yes? If both turbos go to the >DA> one intercooler, then to a single throttle body, single plenum, and into >DA> all 4 you shouldn't have that problem. > >DA> Oh and two turbos at 10 psi is 20 psi the engine would see. To get 10 psi >DA> out of a twin setup you'd only need each to be at 5 psi. Is this correct? >DA> Regards, > >DA> Dave > > > >>>>>>>>>>>>>>>>>>>>Original Message <<<<<<<<<<<<<<<<<< >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> > >DA> On 7/27/02, 10:42:22 AM, "Paul Stanley" <[EMAIL PROTECTED]> wrote regarding >DA> Re: please explainnnnnnnnnn.......: > > > > >>>If syncronisation is a problem what about a custom turbo with seperate >>>turbines all connected to the one shaft? Is that possible? While you're >>> >>> >DA> at > > >>>it... you could go the whole hog and make it a quad turbo. >>> >>> > > > > >>>From: Paul Stanley >>> [EMAIL PROTECTED] >>> >>> > > > > > >>>----- Original Message ----- >>>From: Rick White <[EMAIL PROTECTED]> >>>To: <[EMAIL PROTECTED]> >>>Sent: Saturday, July 27, 2002 2:33 AM >>>Subject: Re: please explainnnnnnnnnn....... >>> >>> > > > > >>>>Mark. >>>>I could maybee se a problem with having one per two cylinders. >>>>if one decides to shit itself one half of the engine would get totally >>>> >>>> >>>different air fuel ratios and maybee the whole thing going bang big time. >>> >>> >>>>Like half of the engine would like kinda stall and the other half would >>>> >>>> >DA> be > > >>>fueled and boosted up big time so the half with the dead turbo would >>>probably lean out?? >>> >>> >>>>I recon one turbo is enough of a worry with out adding another to the >>>> >>>> >>>equasion. >>> >>> >>>>But two spooling up to ten psi would happen quicker with only half the >>>> >>>> >>>induction needed so you would be really getting like maybee 18maybee psi >>> >>> >DA> in > > >>>real terms? >>> >>> >>>>Just my thinking really. >>>>maybee I am way off track here. dunno. >>>>Later mate. >>>>Rick White. >>>> >>>> >>>>--- "mark krawczuk" <[EMAIL PROTECTED]> wrote: >>>> >>>> >>>>>hi, if you have a single turbo at 10 psi, feeding 4 cyls, would it >>>>> >>>>> >>>go >>> >>> >>>>>better/or what would happen if you have two turbos at 10 psi, with each >>>>>turbo feeding 2 cyls? >>>>> >>>>>i was fairly ,sorta on the track explaining to my bro, but then he said >>>>>amongst other stuff, that he cant see any reason why two are better than >>>>>one..... >>>>> >>>>>mark k >>>>> >>>>> >>>>> >>>>_____________________________________________________________ >>>>Get Your free Ozdat Email Account >>>>---> http://www.ozdat.com >>>> >>>>_____________________________________________________________ >>>>Promote your group and strengthen ties to your members with >>>> >>>> >>>[EMAIL PROTECTED] by Everyone.net http://www.everyone.net/?btn=tag >>> >>> >>>> >>>> > > > > > > > > --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/[email protected]/ ---------------------------------------------------------------------
