For folks that are logging boost on the 9 (stock turbo) -- Can you tell me when your peak boost hits? I am hitting peak boost at ~3500 rpm whereas early on I was hitting peak boost at ~3100. The only thing that has really changed (other than miles on the car) is that I have a Nisei LICP. I am wondering if the LICP has hurt spool a bit or if something else is wrong. Thanks

 

i see 3450 or so on the dyno for 23psi. 19 psi around 3100....

but i can make it vary by how hard i load the car before the pull starts, if that makes sense...


cb

 

25 PSI at 2500 in top gear on the road.

 

Thanks Chad & John...That was what I was looking for....So it looks like I am OK....

 

What gear are you talking about though? In third gear out of six I think it hits hard at about 3000. 3600 RPM sounds very late to me.

Have you worked your low down VVT, timing (I advance mine both a lot) and ensured no leaks etc?

 

I need to do a boost leak test....In third gear I hit 24.5 psi at 3500 (starting at ~2100 WOT)....I suspect that I have a leak because I used to (before LICP) hit boost at 3100 in 4th gear....

 

I would suspect that a LICP will give you a better/linear boost curve in exchange of a lil late spool up.

But in order to determine if my statement is true.... we will have to determine the volume of the OEM vs aftermarket LICP. I think that if the volume is higher on the aftermarket.... even for a little bit... would affect your spool up for a few hundred RPMs.

Definitely do a boost leak test! I am installing a new turbo in the next weeks and will do a thorough check on all the charge pipes and vacuum lines. Also check for peaks/dips on your AFR. Those are indicators of a possible boost leak.

 

With a little tuning this evening, I was able to get full boost by 3100 rpm in 4th gear. Before I tuned, I was hitting full boost at 3300-3400 rpm.

 

Wow....Nice work....I suspect I have a boost leak on the cold side LICP and that is causing the late spool....I swapped out my BCS setup for the Hallman MBC and my spool results were the same (with the BCS, I thought the late spool was a result of a loose WG)....I will test this weekend....Oh the joys

 

the boost test is nice and easy, just make sure you have a quality regulator...

we use a silicone coupler, with a pvc cap, and quick disconnect, i then run a short line out of the engine compartment, and have the reg, then another line to the coupler.

im sure this has been gone over a 100 times, so sorry.

if you want, send me ur map....

cb

 

Bump for more help....Could other 9's that are logging boost (I know there are tons out there), please post when you are hitting peak boost? Thanks

 

I think this is a rather difficult thing to compare...because saying "I hit full boost at such and such an RPM" is very circumstantial. Let me demonstrate...

RPM full boost reached,Gear,conditons
4200,1,1st gear roll on WOT at 2k
3000,2, shift immediately upon full boost in 1st gear
5200,3, after letting the car wind out to 7500 befor shifting to 3rd


*These are all true examples that I have logs of. It just goes to show how much the powerband can change depending on how the car is driven. In addition, external conditions will have a great effect on how soon it boosts as well

 

Per the original post ...I am trying to determine in 3rd gear from 2k WOT when peak boost hits....Thanks

 

Ah, didn't see that in your original post...I'll go out and check for you right now.

Wouldn't you know it...Evoscan disconnected at 3k and reconnected at 4k so I can't tell ya...doh...

 

25.5 psi @ 3200 in 4th.

I could hit a slightly high peak figure as I run 96% WDG at 3000rpm.

This is with stock FQ boost control setup - dual solenoid - with solenoid restrictors removed. I am also running John's MIVEC map.