Is the lift pump required? 300HP
 

I have a 2003 SO 5.9 CTD, stock 236 hp and am adding a Smarty Jr. for towing and will not be going over the 336 hp range. My question, is the lift pump required? All you 600+ guys ya but what about the moderate booster. Thanks.

No, Only if you want to run engine.

If you are asking if the factory lift pump will handle your setup, yes, it will. Factory lift pumps can be found for $100 - $150 and are much easier and cheaper to replace than more robust systems. Keep a good Baldwin 5 micron filter (or less) in the canister and you should be good.

I have a Smarty Jr and 60hp injectors and my stock lift pump does everything I need. I get the best performance and mileage on the performance setting. I tried the economy but lost 2mpg.

The 2003- 2004.5 had poor injectors, I know, I had to replace mine. If you haven't replaced them yet, you will...

Run engine?

Thanks notatum! I have been running stock and been very happy mods are new for me. I bough a heavy trailer putting me to the line on most of the categories hence the upgrade questions.[duhhh]

Under normal driving conditions my canister mounted pump worked great when I was running my Van Aaken box. On the dyno, however, you could definitely hear the engine breaking up because the LP could not pump enough fuel to it in the high rpm range. I think my truck was only putting out maybe 310-320 rwhp too.

What do you consider high RPM?

Redline. I'm not exactly sure how high they go with in on the dyno but I doubt they go past the redline....

I am hoping to get another 4-5 years out of the truck till the next latest and greatest thing comes out so if I can get by with the min I will. I am not even sure that I should have order the S $ B filter lol. I liked the Baldwind filter idea though and saved $10 per, lol.

5 micron filter.
Baldwin pf7977
$21.79 Acklands Toronto