Had a huge amount of timing pulled because the SS box only goes to 16psi . I didnt even make as much whp as with my 13 to 14 psi tune .And was just testing to see if we could get it to redline..or close

 

it was done on a 2002 Maxima couple years ago... car dyno'd 275 whp with cams and bolt-on mods... usually maxima's dyno 210 whp or so

 

Wow, 21psi! I can't wait till you get a new EMS. Congrats!

 

Thanks Gman....The 21.7psi was at 6690rpm , so I still got some room for more .

 

How could that high psi only make 389whp?? You think timing threw the whp numbers? GL on ur build.. Ill be attempting something like this in the next few wks with the procharger.. We SC owners must step it up.. Im tired of SC being left behind..

 

I had made 430whp on 13 to 14psi on the serp belt stock pulley system [ was driving it at 420whp ] Mustang dyno . I knew it was going to make more then the 16psi that the SS box is capable of controling . So the last few psi on the SS box , I pulled a huge amount of timing so I was at 13 degree's btdc .

 

The low power at 21 psi is probably limited by the exhaust restricting flow and increasing the backpressure at the blower ..

 

lol..ok

Nothing to do with 13 btdc for timing ????

 

No not saying that...I believe it's a combo.. At 21 psi the exhaust must be capable of flowing one huge CFM or it becomes a restriction to flow and ups the outlet pressure of the blower..

 

Ok...I see what your saying . I have a 2 1/4 dual exhaust

as far as boost . I got one loggged run in to 6150rpm...crazy *** boost this thing is putting out .

old psi.......... rpm .................new psi

................3000 ..................4.1
4 .............3500 ......................5.8
7 ...............4500 .................10.5
9 ..............5000 ................13
12 .............5500 ............15.1
13 .............5900 .................17
slipage ........6150 ................18.1

I spun off all the teeth on the small cog belt thats on the blower it self . Not good ....lol . Looking for a stronger Gates Poly-chain 600 mil. belt . If I cant find one I may end up going to a bigger pulley on the blower itself and be satisfied with what that ends up with . I was going into this just wanting to get to redline with the boost I was making

 

just to add to the above post .

this really does show that the serp belt was [is] slipping all the time with a stock system . Im pretty sure that hte serp belt starts to slip alot sooner than any one thinks . If you go to Vortechs web site and calculate the blower speed with the SQ trim . And the fact that you can only make 11-12psi spinning past the rpm suggested by Vortech . It can only lead you to believe the blt starts to slip in the lower psi range .