usmarine0905

Hi, my 98 silverado, C2500, 5.7vortec, with the big auto trans....248,000 miles...starts everytime, no smoke, no knocks perfect runner... I'm looking to gain a couple more pony's?? I've heard cold air intakes, chip's, etc.. Not looking to rebuild engine yet for the cam swap, run's to good at this time. I notice on the highway running appx 80, if I stand on it to over take another, seems to take it's time to pick up speed to pass.. I have tune up, fuel filter, air filter replacement.... just feeling out for idea's.... thanks

wellmax

i have a 2000 model like yours, 350 engine, with 3.73 gears.
the engine only has 255 hp with 330 pds of torque. Good enough for pulling trailers around but not build for speed racing.
the tow capacity on mine is only 7100 pds.

I guess you could get a set of 4.10 gears for the differential, would give it more power as it would raise engine rpms.

my truck has the std 245/75-16 tires, if your truck has larger tires that will reduce you power.

Take any excess weight out of the truck like tool boxes, etc: this will help some on power.

Remember these old trucks are like heavy bricks going down the road, not a lot to do for them other than a larger motor, like a 6.0 liter. with 300hp.

silverado13

eh theres little things here and there, im the same way, i have a 97 1500 with the 5.7 and i need more power, the problem with the vortecs are that if you do anything major to it, you wont be supplied enough fuel, an example would be cam, stroker kit, heads, ect, so theres no point of doing anything major like that to the engine, thats why im going ot be doing a LS1 swap pretty soon, but you can do things like exhaust, CAI, ported MAF sensor, ported throttle body, and you will fill little difference hear and there, and i could not put 4.10 gears in it because A it kills your gas millage, Bit takes away top speed, and C because itlll only help low end

usmarine0905

Thank you both for the info, i did not know the vortec has a power curve. yes the torque is great and I have the standard tire size..245/75/16, with the 3.73.. ok again thank you for the info.... guess i will just stick with exhaust and intake K&N... what is up with all these "Chips" I hear about?? and do you think a visit to one of the performance shops would help and worth the money?

silverado13

chips? no, they advertise these little "chips" on ebay saying it can gain like 25-300 horse power just by wiring it in and thts a load of crap, but they do have power programmers that you plug into the ob2 port and they actually work really well, you can edit transmission shifts, recalibrate speedometer for different tire size, program the injectors for more power and its worth it, but they go for like 350-450 and i you are going to spend that much then you should just spend a little more and bring it to a tuner and have them tune and dyno it, i know my local shop is only like 550, so its way worth the extra 100

Cpb200

alot of guys around here like the black bear tune they say its better than a chip and tunes it up right
as far as other things i have a 6.0 with 4.10 gears and it moves when i need it to
but the gas kills at 11mpg in the city and 15 maybe 16 hwy@65-70mph and thats everything stock
if your serious i would do a rebuild and bore it out with a custom exhaust for better flow

silverado13

its not really a good idea to bore out a 5.7 vortec......the stock injection system can barely provide the engine with enough gas, if you go and bore it out or add a cam, it will lean it out at higher rpms and youll have to worry about burning valves, if your going to put the money into a rebuild, you should just go with a motor swap, thats what my next project is, ive considered putting in like a LT1, LQ4, LQ9, but i finally set my mind on an LS1 swap

usmarine0905

What about oversized injectors? again these are just question for my knowledge.. I am going with a really good performance tuneup and cold air intake... but not too the point of killing my avg MPG.....LOL

silverado13

they dont really make any over sized injectors for the truck, they make them for the boats that they put the vortec in, but the set of injectors was like $1500 last time i checked, so if your going to spend that kind of money, you should just put it towards a new engine

janesmith

Hi i have a 302(5.0)and i m thinking to getting it rebuild..i am looking for a complete engine kit..well all replies are also helpful..

Thanks
Power chips