Hmm, i think i tweaked the pump a lil' too much this time.

[OKish]

Well, i was working on the truck and i decided to rip the top cover off and do some more tweaking. i turned the starwheel another turn cw (3 turns in total), ground the nylon spacer on the fuel cone to half its thickness, turned the smoke screw in another turn(sits below lock nut one thread), and turned in the full fuel screw another half turn (maybe in 2 1/2?) I knew it was too much when i smoked out the neighbors when i started it up. when i was driving it was smoking/ hazing anywhere below 15 pounds boost. hmmmmm, that must not be good for mileage eh? i got an extra 2 pounds of boost (now at 34psi on a 18cm2 housing). egt's are at about 1400*. i think i should back the starwheel off and the smoke screw off and turn the full fuel in another 1/2 or 1 turn in. whatcha guys think?

 

[bmoeller]

Mess with the AFC for sure. Should take care of the low boost smoke.

 

[dpuckett]

I agree- tighten the AFc up to where the starwheel is even with the top of the "well. " Also, make sure it idles down in a reasonable time. If it floats down, time to back it out a little.



May be time for turbo upgrades- I had a PDR Hx35 on my early 91 and it held the EGTs from pegging the pyrometer. 40+ psi and 1500 deg was about all I saw.



Daniel

 

[OKish]

I agree- tighten the AFc up to where the starwheel is even with the top of the "well. " Also, make sure it idles down in a reasonable time. If it floats down, time to back it out a little.



May be time for turbo upgrades- I had a PDR Hx35 on my early 91 and it held the EGTs from pegging the pyrometer. 40+ psi and 1500 deg was about all I saw.



Daniel

yea, black = unburt fuel = wasted fuel, i'll back the starwheel and smoke screw out. the rpm's come down fine but i think its time for a turbo and injector upgrade. what do you guys suggest? i really dont want to go through the trouble with installing a dang intercooler.

 

[dpuckett]

I think you're getting plenty of fuel- you need air. And, sad to say, an intercooler would help you a lot. I picked up a good deal of bottom end just by taking the paper towel out of the turbo side of my intercooler.



Daniel

 

[pepecat]

the only way you're going to get rid of that smoke is the full fuel screw. Even without AFC fueling (fuel pin at top of the smoke screw setting bump stop) you're going to have to turn that down before you melt a piston at 1400+ or spin that baby h1c into orbit and send aluminum shavings/particles into your intake. the MAP effienciency for our turbos is at about 26 PSI MAX and that is stretching it. I can get up to 35 psi easy as well with just full fuel screw, it's no feat or accomplishment, have you upgraded your headgasket because if not you are in the danger zone of blowing it out at over 30PSI esp without warming the truck up, fwiw.

I am where you are at with mods I think. 4" exh BHAF intake except I have a 16cm housing. I haven't decided where to go next in terms of air. I'm at the limit at with this setup and the fuel is not the limitation.

 

[Smokey 01]

Yeah that head gasket won't stay happy for very long at that amount of boost with a stock H1C. That is a lot of drive pressure. My 1990 lost a head gasket with 35 lbs from the stocker. Well I did spike it up to 40 psi a couple times.

 

[OKish]

Yeah that head gasket won't stay happy for very long at that amount of boost with a stock H1C. That is a lot of drive pressure. My 1990 lost a head gasket with 35 lbs from the stocker. Well I did spike it up to 40 psi a couple times.

im really going to melt a piston at 1400? im not towing at 1400*. cruise is usually in the 500-900* range. what would you guys recommend for a turbo and ic setup then?

 

[dpuckett]

I should have a 1st Gen setup in a few weeks. You can go for used 1st or used 2nd Gen (bigger pipes and i/c w/ 2nd Gen). 3rd Gen wont work- too wide to fit between the frame rails up front.



If you stay at 1400 for a short time(<30sec), and the temp drops back down fairly quick, you SHOULD be ok. No guarantees, though. What is your timing at?



-DP

 

[OKish]

I should have a 1st Gen setup in a few weeks. You can go for used 1st or used 2nd Gen (bigger pipes and i/c w/ 2nd Gen). 3rd Gen wont work- too wide to fit between the frame rails up front.



If you stay at 1400 for a short time(<30sec), and the temp drops back down fairly quick, you SHOULD be ok. No guarantees, though. What is your timing at?



-DP

well, thinking of selling the setup?

 

[OKish]

well, i backed off the starwheel 2 turns and the smoke screw 2 turns. egt's are down and smoke is back to normal. but boost is still up to 34psi, im thinking i should back the fuel screw down so i have max boost of 30 or so? i bet i can get 40 psi if i load it down.