My car suffers from very low vacuum. HKS cams it was around -7psi with the BF's it is around -4 to -5 with the AC on forget about it... My question is A) how can you boost vacuum on a stock ecu car? and B) does using an AEM EMS allow more vacuum to build with a big cam like I have? The car idles fine but with quick clutch in it will not like that and is usually a total pain in the *** to start back up. Setting the idle at 1200+ rpm also does nothing. It has the problem that most have when you put the clutch in fast and get on the brakes while stopping. It is just 10X worse with these big cams. I know these cams are not suggested for stock ecu cars but what does the AEM offer that the stock ECU does not to catch it before it stalls out?

 

Have you tried advancing timing a bit at idle?

 

Yes

 

What is the idle timing set to?

Plus
You should be able to tweak those idle stepper tables and get it dialed in. Mellon should be able to mess with them im sure

-4 to -5 damn

 

I dunno i run hks 272 intake and exhaust cams and the jdm map sensor is logging usually -5psi at idle. My idle is around 900 and I have never had a problem.

 

Dustin that vacuum isn't that low, mine is -5 to -6 with the HKS 280's at 1000rpm...send me some logs of it stalling and maybe I can isolate the problem.

 

The vacuum is about right for the cams, play with the tune and timing and you might be able to get more

 

ok chris I will try to get u some. thanks for ur help!!

 

cool, I'll keep an eye out for them