ILL ADMIT IM KINDA NEW AT THE TURBO THING NOT MUCH EXPEANCE WITH CARBS ETHER BUT I LEARNED ALOT RECENTLY. I JUST DONT KNOW IF IM DOING ANYTHING WRONG, I HAVE A SBC 350 NOT FORGED INTERNALS WITH A TURBO FROM A 2012 DODGE CUMMINS 6.7L. WITH A 650 MIGHTY DEMON. MALLORY 250 COMP FUEL PUMP -8 LINES AND FUEL CELL, MALLORY +1 BOOST REF REGULATOR. THIS USED TO BE NATURALY ASPERATED SET UP UNTILL I GOT A FREE TURBO THROW WORK. RUNNING 8PSI OF BOOST, TRING TO KEEP IT SAFE. NOW THAT MY FABERCATION PART IS DONE IM WORKING ON TUNING, I STARTED OUT WITH JUST JETS, WAS SO LEAN COULD NOT GET PAST HALF THROTTLE, RUNNING 93 PRIMARY AND 110 SECONDARY JETS, WIDE BAND IS GOOD AT HALF THROTTLE ALITTLE RICH? 10.9AFR BUT PULLS REAL HARD, FULL THROTTLE LEANS OUT 14.8 AFR AND FALLS ON ITS FACE, JUST STARTED FINDING OUT ABOUT VENT TUBES, TRIED IT LAST NIGHT AND IT WAS VERY STRESSFULL. PUT ON 8INCH 5/16 LINES AND COULD NOT EVEN PUT IN GEAR I GUESS VERY RICH? MY BENDS IN THE NEW VENTS SUCKED BUT WHERE NOT CINCKED, TRYED SHORTED VENT TUBES, AND WAS BETTER BUT IT SEEMS IF I PUT A BEND IN THE TUBE AT ALL IT DOESNT RUN. I SEE EVERYONE HAS LONG TUBE ON THE VENT, SEEMS IF IM LONGER THEN 2INCHES IT DOESNT RUN. DOES THE BENT MATTER IF ITS NOT PERFICT. DIDNT HAVE TIME TO CHANGE MY JETS BACK, I KNOW I NEED TO BUT TIME IS ALWAYS A ISSUE ANYMORE. JUST LOOKING FOR INFO. PICK YOUR BRAINS, IS ANYTHING IN THIS SET UP WRONG ECT.

 

I have not done any blow-thru tuning yet, but I've done a LOT of N/A carb tuning. I'd recommend going down about 5~6 sizes on the primaries, put on the extended vent tubes, then check your AFRS on the part throttle primaries alone. You will probably need to open up the PCVRs once you get into the power valve range. Once you get the primaries close, THEN start working on the secondaries.

 

Your fuel pump is not enough. Plain and simple.

 

Highly dought my fuel pump is not enough, 250 gph 20 psi max 3 weeks old.... So tonight i got new tubing and made nice bends in the new vent tube extentions, they are 5 inches long now. Then changed out my jets in 8 then 4 then two size increments. Now im running 66 pri and 68 secondary jets. Got my primary at 11.7 afr and has lots of power at half thottle. But now here is my problem full throttle way rich 10.4 so my pump seems good right? But i have never heard of jets in the secondary being smaller than the primary!!!! My smallest jets i have in my kit are 65. If i put them in the secondary i still dont think it will make it run that much leaner at wot. Got a flat tire and ran out of time to put in the 65.

 

Im thinking shortening the secondary vent tube by 1 inch only and see what it does before i move the secondary jets again.. Any thoughts?

 

What size are your secondary HSABs? I'm thinking they may need to be opened up a couple thou...

 

I have no idea they are stock what ever the 650 mighty demon comes with.

 

They should be replaceable, I would figure out the size and go up a bit, or just drill them a couple thousandths bigger.

 

https://www.theturboforums.com/thre...t-ONLY-quot-no-replies-or-comments-etc/page16

a link may help you a little

 

I need some info on HSAB, where are they located what do they do ect.

 

High speed air bleeds? Right?

 

Correct.

 

Ok on this carb there is 8 air bleeds, from what i gathered i
need to enlarge the two inner rear air bleeds ? I just
removed them and there is no number on them. So i dont
know if i should drill them out ? Or should i?

 

I would use a drill bit to find out what size they are, then go just 1 or 2 thousandths bigger. I use a pin vise, (drill bit holding tool), but if you don't have one, a small pair of vise grips will work, just work it by hand, brass drills rather easily with a nice sharp bit. You could also order a variety of sizes to save you the trouble of drilling, but you still need to find out what size you are starting with to know what size range to order.

 

Ok just got it dialed in 100% happy with it, broke slicks loose doing 50mph. drilled the two secondary inner air bleeds first to 1/16 then to 5/64th . Got it to run 11.3afr wot. im happy with that now its time to head to the track, have no idea what its gonna run. thanks guys

 

The turbo is vgt correct? Do you have the rack all the way open or closed?

 

Yes it is vgt , i drilled a hole throw the actuator, welded a rod and lever on the valve. So i can change it back and forth , but i havent messed with it to much, i have it all the way in the foward position, where the exhaust is louder.

 

Forward is Open
Backward is Closing the vane

 

Went to the track last night pretty disappointed only ran 13.1 i was hoping for 12.5 but it is a heavy ass truck and only running 8psi of boost. Something just dont feel right still half throttle frees great but full throttle feels weak. Just gets louder. Its running 10.9afr wot maybe thats to rich?