[SpyVO]

So I have a Holset HE-351 with the 9cm turbine housing.  I've been data logging it for a while now, and it spools up very slowly.  This seems weird to me, since I've always been told that's the small turbine housing, which *should* equate with speedier spoolup.  

This is with an E6.  I get about 7 psi at 4000 RPM, and about 19 psi at about 5000 RPM.  Full boost is right about 20 psi, which ends up being about 5500 RPM...that last bit takes a while, and I'm not sweating that.  

I just put in a BigR X cam, and it's retarded about 3.5*.  I'm probably going to experiment with this to see if changing that moved the spool time around.  

Also, spark timing at the onset of boost...if I retard that some as the boost is coming it, will the thing fall on it's face, or will it spool up faster, enough to essentially offset that?  I'm probably going to try that too.

[Racingjake]

I'd check waste gate operation, maybe it's not fully closed and venting during spool up ?

I have 2 ignition maps in my Pimp, a 20 degree max at boost and a 24 degree I can feel the difference on the road.

[SpyVO]

Yeah, been thinking about that, the wastegate sealing...I'll check into that.  

What are you running for fuel?  How much boost?  I'm on pump gas still, and I'm wondering if I'm pushing it.  I probably need to start a new thread for that, but yeah 4 degrees at the top end...that's a good amount.  I've been reading a LOT of results threads, and I saw one guy was running 25-27 psi on pump gas, but the timing was pulled back to 17 total, I think.

EDIT - Ah, see the sig now... haha

[Racingjake]

Yeah, been thinking about that, the wastegate sealing...I'll check into that.  

What are you running for fuel?  How much boost?  I'm on pump gas still, and I'm wondering if I'm pushing it.  I probably need to start a new thread for that, but yeah 4 degrees at the top end...that's a good amount.  I've been reading a LOT of results threads, and I saw one guy was running 25-27 psi on pump gas, but the timing was pulled back to 17 total, I think.

EDIT - Ah, see the sig now...  haha

I'm a little late like usual

Running 93 at 20 degrees with my Pimp ecu and I do have a table switch set up with adds 4 degrees across the map with boost at 20 psi max.

I've hit the over boost set at 26 psi before and you will know it LOL when I had max boost set higher. I haven't done much for 2 years but drive it.

I have a 50 trim T3/T4 with a .46 AR and it built boost fast but you could feel the top end lay down compared to the 63 AR, after 500 miles I put the 63 back on and could tell the difference and been running it sense. I'd like to find a turbo with the best of both worlds too.