some timing issues on a 6.2

[dually man]

Well, I just got the 6.2 with a Ats turbo into my once TBI gasser K5 blazer. Previous history on NA 6.2 is: stock ip fuel rate, advanced timing by thickness of line on ip. dual exhaust and a 6.5 diesel electric lift pump.
NEW status of 6.2: Fuel rate turned up one flat of a allen wrench, timing marks lined up, ats turbo with 5" hood stack, stock EFI gas lift pump in fuel tank that runs 10 to 15 psi.
SO my problem is that my engine rattles more now after the swap, sounds advanced, I moved the advance lever and the engine fishbights real bad at idle. I get LOTS of black smoke at any throttle. I use my cold advance on a toggle switch so I can hear a slight difference in sound when that is activated. Should I retard my ip somemore? I been searching the forums for an anwser but cant find a simular situation....

 

[ak diesel driver]

If it's mech IP,your running to much fuel pressure, which will affect the advance in the IP

 

[dually man]

yep, it's a db2 mech pump

 

[3500GMC]

Constant 6 psi is all you need, and all you should use.

A stock lift pump for a 93 6.5 will do this well.

Anyhing beyond that, the trick is to increase GPH not PSI..

 

[dually man]

So this morning I retarted the timing by the thickness of the line on the ip, she dont blow as much black smoke now but still kinda sounds like a international powerchoke.

 

[WarWagon]

If it's mech IP,your running to much fuel pressure, which will affect the advance in the IP

X2, the transfer pump inlet is where housing pressure is referenced. The high fuel pressure will affect housing pressure and housing pressure directly affects timing. Get the proper lift pump with lower pressure as the DB2's are sensitive to fuel pressure.

 

[dually man]

tested my fuel pressure today, it was at 10psi..

 

[just a number]

where was the 10psi pressure reading taken, pre filter or post filter?

 

[dually man]

pre fuel filters

 

[iamdave0887]

Your probably ok then.

Check it after the filter's to be sure.

I'm running a Holley Blue fuel pump for my lift pump on my K-5 with a Banks T04B turbo setup. Pre-regulator it's probably 15 psi. Post regulator the underhood gauge(so i can only see it at idle or free rev underhood) ranges between 6-10 psi depending on fuel temp(no in cab gauge yet).

After the regulator is goes into the stock fuel filter housing then to the IP.

I only get smoke when i lay into it since with the T04B the boost builds slowly(no-wastegate).

Avoid the stock 6.5 LPs. Sure they work perfect when new but i haven't had one last more than a year yet. The pressure slowly drops as the pump "breaks in". I've exchanged 3 or 4 of the Airtex 93 6.5 LPs under warranty. I've made it a habit to exchange them before the one year warranty expires.

Go for a Walbro or a Holley red/blue pump. The Holley's don't have a "yes or no" as far as diesel fuel useage. It just says not for use the alcohol based fuels. If it can handle gasoline which is a solvent it should handle diesel which is a lubricant just fine.