Turn the pump down????

[johnnyb1]

I JUST BOUGHT A 7.3 LONG-BLOCK FRESH FROM THE MACHINE SHOP { WARRANTY AND ALL } FOR $800. COULDN'T PASS IT UP. MY QUESTION IS HOW MUCH TO TURN DOWN MY PUMP. MY 6.9 PUMP IS TURNED UP PRETTY HIGH JUDGING BY THE SMOKE AND RUNNING TEMPS. I'LL BE USING MY BANKS AND INJECTORS. IS THERE A RULE OF THUMB ON THIS? [LIKE A CARBURATOR, TURN IT DOWN ALL THE WAY AND COME OUT 2 TURNS,ECT] I WANT IT TO RUN STRONG BUT RUN LONG. ANY ADVICE WOULD BE GREATLY APPRECIATED.

 

[tbirdfiend281]

Why would you have to turn down the pump for a larger displacement motor? I would try it as is just ckeep an eye on the gauges

 

[icanfixall]

The above is partly true. Its easier to turn down the fuel before the pump is on the engine but its not hard once its on there either. What pyro tempos are you seeing on the 6.9. Boost is important too. At this point you have two choices. tunr it down one or two flats and test run it or leave it alone and test run it. Doing this will make it easy or a little tuffer to do. Some will feel to just run it where others will say to drop it down now when its easy to do. then if you feel its down too low simpley turn it back up..

 

[johnnyb1]

I could get almost 15 lb. boost with the 6.9. Don't know about EGT [no pyro ] Bigger displacement really isn't my concern. Only about 15 more inches. I just hate to pour fuel into it if it doesn't need it. The 6.9 was fun to drive but it only lasted 100k miles. And even on a winter day the water would run 210-215. Just seems like it was turned a little too much. It smoked like an old Mack. I may install it as is and see what it does on this engine.

 

[johnnyb1]

When I get the engine done the next project is an OD for the C6. One project at a time. With the new engine and the condition of the ol girl it should last me several more years.

 

[icanfixall]

Ok... So you have lots of smoke... Plenty of boost.. Coolant temps higher than is notmal.. And no exhaust temp because you don't have a pyro gauge. And on top of all this the engine lasted about 100,000 miles. Your needs are a pyro or the newer engine will not last either. We have no information on what the engine failure was to cause you another engine. I suppose its not important why the engine died but whats really important is installing a pyro. Information is chief. Its also power. Without a pyro telling you this very important temp info you are testing the limits unknowingly. Please don't be a lab rat for your next engine... Install a pyro no matter what the costs are. Now if anyone chimes in here posting that the idi turbo trucks came without a pyro please don't. That has nothing to do with an engine that was normally a non turbo setup and was running a hot turned up pump with no knowledge what was going on internally.

 

[franklin2]

I did this exact same thing on a 94 factory turbo f350. The guy had to have the pump rebuilt because of a leak, and while it was in the shop, the rebuilder "turned it up" a unkown amount. It smoked when you got on it hard pretty bad, which didn't bother the guy who had it, but he felt is fuel mileage was suffering.

So I got the truck and turned it down 2 flats. I then tested it, and the smoke was gone, and it was noticeably down on power, but he wanted to try it. He hauls a boat down to the eastern shore every year, and after I turned it down 2 flats, he said he was losing speed going up the east side of Afton mountain on I-64 coming home hauling the boat(he sets the cruise control). So I went back in and turned it back up one flat, and it was perfect, just a little bit of smoke, and plenty of power going up the mountain. I felt like he might have gained a little bit in fuel mileage, but I am not sure he really did. I do know afterward when going home from work, he would have good heat out of the heater in about 2 miles. After I turned it down, he doesn't get any heat out of the heater till about 5 miles down the road.

I wouldn't turn it 2 turns. I would be very conservative, the adjustment is touchy. When you read "turned it one flat" that is one flat on the allen wrench. The allen wrench has 6 sides, so that is only 1/6 of a turn.

 

[79jasper]

I would turn it down, at least until you get a pyro.
Cheap insurance as most would say.

 

[tbirdfiend281]

I agree, that anyone who is going to turn a pump up, even non turbo, should absolutely have a pyro. I know I am getting one before I start playing with all that. I will probably even have the turbo on before the pyro goes on and I play with the pump.

 

[johnnyb1]

Many thanks everyone. I agree that a pyro is needed. Water temp is not enough info. Too many variables can make it run warm. I need to see what the egt is before I start making more adjustments. I had a 700 hp Cummins years ago and I saw guys turn way too much fuel to their trucks trying to run with my truck only to burn up their engine. There is more to power than just alot of fuel. I'll install a pyro and a trans. temp gauge and see where I'm at.

 

[icanfixall]

Thats a great idea about installing a pyro. Having more information from gauges will make any adjustments easier to see what you have done. More information means you have more power to make moves... Information is power. Power is the ability to make informed decisions on what you are doing...

 

[argve]

Pyro pyro pyro

If you are going to run a pump that is turned up you need a pyro or don't use the entire travel that the pedal offers.