Omega Owners Forum

Chat Area => General Car Chat => Topic started by: RobseyMV6 on 24 July 2011, 21:44:50

Title: Any one know what psi/bar
Post by: RobseyMV6 on 24 July 2011, 21:44:50
Can i run my omega 3.2 up to? (safely) Over the past two weeks i have fitted a M62 Eaton supercharger on the side of engine. now a need to run more boost but whats safe?

As need to buy (bov) blow off value
Title: Re: Any one know what psi/bar
Post by: cem_devecioglu on 24 July 2011, 22:41:44
a trial error method on boost pressure will soon end up with a bang.. so be extremely careful..
Title: Re: Any one know what psi/bar
Post by: feeutfo on 24 July 2011, 23:41:33
Seen talk of 6psi. But can't remember if that was considered a safe level.... Or when it went pop and destroyed the bottom end.  :-/

Not helping much am I Dad!  :-/ :)

Got a video or sound track?

Keep us updated. But FFS go steady on that crank etc. They don't take much going by older posts on here.  :'(
Title: Re: Any one know what psi/bar
Post by: TheBoy on 25 July 2011, 08:34:10
I drove my mates Lexus when he sent it up to 17psi, rather thing flew in a straight line.  The only car I've driven that spun the rears in the dry at a 100mph gear change (TC fuse missing, as being a jap import, limited to 110mph with fuse in ::)).  Shame it couldn't do corners. Or brake.

That was a considerably stronger engine though (basically the 3l twin turbo from the Supra)
Title: Re: Any one know what psi/bar
Post by: Kevin Wood on 25 July 2011, 09:44:35
If no steps have been taken to reduce the compression the boost is going to be really limited, and run super unleaded fuel only. Depends how resistant to knock the engine is in the first place, how effective if any the charge cooling is, how strong the spark is, etc. so it's really a case that you have to suck it and see. Start small and work your way up being very careful.

What engine management are you running? If it's the stock ECU you have no way of enriching the mixture under boost nor properly mapping the ignition so another note of caution. Get an OBDII reader and watch the knock retard like a hawk.

I would also recommend a wideband lambda sensor so you can be sure the fuelling isn't going lean and, at some point, going to a mappable engine management system so you can control what's going on.

Also, bear in mind that the standard injectors don't have much if any flow in reserve and, unless you reference the FPR to the boosty side of the intake they will be working at effectively reduced fuel pressure too.

Still, an interesting project and it will be good to see how you get on.
Title: Re: Any one know what psi/bar
Post by: RobseyMV6 on 25 July 2011, 21:38:07
Thanks for that, at the moment there is no psi running yet but its all ready to place a 10psi bov when i order one in but then need to work out how to change value from normal air to supercharger air, think i've worked it out but vac won't yet close the re-open when i turn supercharger off as can turn on and off in side car.

Update soon....
Title: Re: Any one know what psi/bar
Post by: cem_devecioglu on 25 July 2011, 22:01:58
I recommend you read Kevins post carefully..

and I hope those will help a bit

http://forums.hybridz.org/index.php/topic/30463-supercharger-boost-calculation/

http://turbochargersworld.com/turbo-boost-pressure-calculation/

http://www.pumaracing.co.uk/pp04.htm

http://www.ehow.com/how_5672007_calculate-supercharger-boost.html

and I found those interesting

http://www.superchargersonline.com/faq.asp

http://forums.pelicanparts.com/porsche-911-technical-forum/444521-supercharged-race-car-build-2.html
Title: Re: Any one know what psi/bar
Post by: Kevin Wood on 25 July 2011, 22:10:02
Quote
Thanks for that, at the moment there is no psi running yet but its all ready to place a 10psi bov when i order one in but then need to work out how to change value from normal air to supercharger air, think i've worked it out but vac won't yet close the re-open when i turn supercharger off as can turn on and off in side car.

Update soon....

I assume the valve can be adjusted up to 10 PSI? Because I think starting at 10 PSI is going to end in tears. ;)
Title: Re: Any one know what psi/bar
Post by: RobseyMV6 on 25 July 2011, 22:18:38
Ok may 5 psi i'll start it at, might have to pop over to see you kevin  ;)