Well, hopefully I will be getting my 03 SC/SB 5.3L Silverado soon. When I get it I plan on doing some modifications to it. Tell me what you thinkof these.
-Free mods (EGR, TB Bypass)
-Intake pipe w/ homemade ram air
-160 therm.
-True Dual w/ X-pipe
-Electric Fans
-ASP pullies
Within a year.....
-LT headers
-TC
-N20
Not sure about what direction to go in the way of engine management yet.
Suspension of some kind (maybe 2/4 drop, traction bars, adjustable front shocks, rear sway bar.)
So what do you guys think, any suggestions would be greatly appreciated.

 

Just wondering...With these engine modifications would running LT headers/true dual 3 inch with x-pipe result in too little back pressure and hurt the valves. Also what if I were to also gut the cats? I wouldnt really think that it would result in too little back pressure, maybe just lose of some low end torque. Any advice is greatly appreciated.

 

gutting the cats will lose some low end torque, not a ton though. you don't have to worry about the valves, i've been running no cats and open exhuast for a year or so now and no problems at all. sounds like you have a good plan, have fun.

 

If you can get your 03 dynoed BEFORE the mods. I wish I did that with my truck! It would be very interesting to see what a stock 03 makes to the wheels. I have yet to see any believable stock 03 dyno numbers. What I have seen, on this forum, would suggest that at least one of the 03s made over 300hp+ at the FLYWHEEL stock/from the factory. Thats 15+hp over what GM is rating them at the flywheel. So I just dont know what to believe.

 

Don't gut he cats. They have almost no restriction when running stock manifolds. If you just have to take them off, have some spools made to put in there place with flanges. Then you can put them back in when needed. You will have to use 02 simms or LS1Edit them out. Also, at this point, a nicely done single exhaust would be best for you until you put longtubes on. No point in doing a lot with the exhaust while your running stock manifolds since the restriction is still there. The stock manifolds flow very weel and used with nice catback system should get you 10-15 at the wheels. When you go longtubes, then you can open it up a little more. You will loose a little off the line, but it will be back after 2000rpm with a vengence.

 

i think installing a TC should help you off the line. i lost alot of low end TQ when i installed my exhaust and K&N. but made much of an improvement after the yank3000 went in. electric fans and pullies should help you take off too

 

Umm...Maybe when I get the truck I should just go ahead and splurge for the LT's, I will be getting back around $1500 from other mods that I would sell from my present car, so I know I would have enough. As far as the dyno goes, I plan on getting the truck dynoed when I get it at a local performance shop, just so I will have a nice baseline to work with. Thanks for all the info, cant wait to