Increasing boost

[Arif]

Finally got the Z running great (at stock boost). I changed the timing values on the SDS. I have an external wastegate and a manual adj. boost controller. How do I increase the stock boost to about 10psi? Do I need to make any changes to the wastegate or sds values. How sensitive are the manual boost controller? Do I have to turn it quite a bit for it to increase the boost?

Fire away guys!!

[Guest Tim78zt]

Hi Arif!

Which MBC did you install, and where is it installed?

 

Tim78zt

[Scottie-GNZ]

Arif,

 

as you increase boost, you not only want to increase the fuel but you also want to retard the timing. There are 2 maps you need to focus on and if you do them right, you need to do nothing when you increase the boost.

 

The maps are:

MANPRESS - adds fuel based on manifold pressure. You build this map to add fuel as boost increases all the way to limit of the map sensor. If done correctly, when you go from say 10# to 15# boost, the added fuel required is already programmed in.

IGN RET/MANPRESS - retards timing as boost increases. Same principle as MANPRESS but instead you retard the timing as boost increases.

 

MANPRESS works in conjunction with RPM FUEL. Where RPM FUEL is your basic fuel map for normal driving, MANPRESS adds fuel only based on manifold pressure value. Do not increase RPM FUEL to compensate for boost. Well, you can, but you will have that increasedfuel all the time even when you do not need it .

 

IGN RET/MANPRESS works in conjunction with IGN. IGN is your static and advance timing and IGN RET/MANPRESS comes into play when you hit a specific manifold pressure. The combination of the 2 is your total timing. E.g., if the value for IGN is 33* at 5000 RPMs and you running 12# boost and have a IGN RET value of 10* at 12# boost, then the total timing is 23*.

 

HTH