5 psi drop at 15 psi of boost is ok but it clearly shows that intercooler is gonna get uglier as target boost increases

 

So 19 is pre intercooler. And 15 is post intercooler?

 

He's running 15 psi wastegate spring, no boost controller, looks like he's seeing 19psi pre-intercooler, 14-14.5 psi post.

 

A good intercooler will have 1-2psi drop at 20psi, clearly there is room for improvement on yours. Pretty sure you are over the hump with your turbo and cranking up the boost will not add any more power, even with the same timing. Not all 3" intercoolers are created equal.

 

^^correct.

Could be. I'm going to leave the boost gauge hooked up pre-intercooler and see the effects when I drop the wastegate spring back to the 12lber.

I've had my eye on a treadstone intercooler so maybe that'll let me get a little more out of the magnum.

 

Ive had good luck on builds ive done with a treadstone

 

What are your air temps?
Lower boost and newer boost level.
What's the final goal with current set up?

 

Rick,

Air Temps (don't know how good of a comparison this is):

12-13psi (ambient air 53F): 79F idling in staging lane / 82F post burnout / 111F through the traps (hit 111F right at 2->3 shift, maintained 111F through traps)

14-14.5psi (ambient air 69F): 88F idling in staging lane / 100F post burnout / 144F (hit 144F just after 2->3 shift, maintained 144F through traps)

My goal keeps shifting right. I'd really like to see 10.99 out of the 4.8l on 15psi or less (there was a time I thought it would get there but I'm not sure). Then I'd like to add meth. I think an end goal for this 4.8l is 700-750hp and hope that it lives for a while at that level.

 

111 not bad at 12-13psi.
144 at 14.50 psi is a 30+Temp jump for 1-2psi more seems a tad hi.
But still not gross.
If you hot lapped, it could make your temps keep rising.
So it was hotter air temp with less timing. Both mean less power potential.
Your are at the end of any 12x3 core.
I would recommend you get our 3" or 4" race intercooler.
They are a different core design, 23" tall, with larger inlet/outlet.

 

Horizontal Intercooler is preferred to the vertical core.