I've got a 2000 5.7 automatic K2500 w/3.73 gears, that I pull trailers with. Did the superchip re-calibration, duals, airhog cleaner, but still sluggish pulling and only about 10 mpg on the road empty. Is there anything fairly inexpensive that will get me more power, or milage?
Not really. About the best bet I could see for reasonable money would be a cam swap or something. Duals only help for high rpm, might think about doing a good single or at least a cross over for towing. Same with the "free flow breathers". They are only of marginal use unless replacing one of the REALLY bad OEM styles, but most OEM styles are more than adequate for a tow rig. Your stock breather setup was likely as good or better for towing than the one you put on it, but I don't know that one for sure. Basically, you need an over all "package" that works together. The engine needs all the parts designed to work in the same rpm range. Heads, cam, intake, exhaust, etc. all needs to be spec'd to work in the rpm range the engine needs to do most of it's work in. For tow rigs and daily drivers that need good drivability, tow ability, and fuel mileage maximized, we're talking about a package designed to maximize rpms from say 1500-3000 max and gearing (tans and axle) capable of keeping the engine in that sweet spot most of the time. Dual exhaust often hurts power in that range (really coming into it's own only above 3k or so, depending on other factors). Same for most headers and chips which are designed for "max horse power" and that usually means 3-5k target rpms. You need to get the "low rpm torque" spec'd chip and headers and so on. Like I said, you gotta keep your eye on the target and make things work together. Worse thing in the world is dropping a lot of coin on piece-meal "performance mods" without an over all "plan". Second worse thing is falling for unproven stuff like "cyclone" inserts and such (IMO this includes "Air Aid" type breathers and TB spacers too!). That 5.7 will never be a "towing god" but it can do a pretty decent job if you go about building it right. However, if your going that far, it might be better to go with a new motor with the logest stroke possible (leads to easier/more low end torque) like a 400 SB or 454 (best choice, BBs just naturally build more low end grunt easier). Or, step up to a diesel like the 6BT or other similar transplanted diesel (Perkins, Cummins, even a DI T/I IH/Ford can make a suitable candidate) to really get on with the program. Good luck.
Cam for 350 What would be the best cam for towing in my '00 Chevy K2500? How would this affect the MPG?
That I have no clue on. The information in my post is generic for any engine. And the cam suggestion was just a rough guess based on knowledge of older engines anyway. I really don't know anything about that particular motor. And I'm also trying to work out the best cam selection for one of my motors right now, it's tough to do if your not very well versed on the engine and application your dealing with. Back when I fooled with engines it was muscle cars and carbs. Now I'm having to rebuild an EFI 350 that my son threw a rod on (which damage the old Engle roller cam) and I'm having a hard time deciding which way to go… So, to answer that question or figure out where you really want to go with this is going to take some research. That or get lucky and find someone with a very similar/same engine and goals who did the research AND you can trust to have done it right. All I can offer is, "good luck".
If you call Comp Cams and tell them what you have and what you want to get out of it they will set you up with a cam.
Talking to pre-sale techs is good advice, and I've talked to many of them, but they range in quality about like "parts guys". Most of them barely know how to follow the computer screen scripting, but once in a while you find a "gem" who really does know his/her stuff. Will the tech know enough and be able to properly account for the "chip" changes and duals? Or just read from a script that simply says "for towing and this motor, recommend this cam". And of course they will tell you that *they* make the "best" cam for that application... Some people flat don't like CC, some think Crane is a "has been", and so on. So you'll have to look elsewhere to find out if CC, Crane, Engle, or someone else actually makes the best cam for your particular needs. But even if you get a "gem", that's only going to get him a cam recommendation for that motor and application. Assuming I'm right in guessing that a cam would yield the best bang for the buck given what he has and what he wants, then that might be good enough. But for all I know there might be something better than a cam based on what he has now. I don't mean to be a wet towel here, but getting the maximum return on work/investment is a science, not an art. It seems most people just grab some performance parts and start throwing them at a vehicle hoping something magically turns it into a power house.
