Okay so i have a 2003 monte carlo ss over 200k miles on it i am the 3rd owner engine has been maintain new spark plugs ,alternator,radiator. I plan on changing starter and water pump as there are still factory. I plan on making performance upgrades but not really sure where to start or if i should jus rebuild with a new engine not really a car technician need experts and car owners help i know my car fast i jus want more speed any help

 

It depends on what your looking to spend. 200k is a lot of miles

There are lots of cheap bolt-ons available that you can use and still use if you later swap of rebuild the engine so your not wasting money. Cold air intakes seem to be a popular place to start. If your planning on changing the water pump you could install an electric one - the performance enhancement is minimal, but sometime it just feels better when changing something like that knowing that you've upgraded over OE. And of course, an exhaust upgrade sounds better and gives mental horsepower. Upgrading the exhaust doesn't really see immediate performance gains on a stock car, but it's a good supporting mod for things to come.

 

IMO that's too much mileage to start putting a serious amount of money into performance mods. No doubt it's probably got some life left in it, but making a lot more power isn't going to help that.

At a minimum I'd look into a lower mileage junkyard engine to start building up.

 

And should you choose to go to crazy, I bet you Transmission is more tired than the 200,000 mile engine. Budget about $25,000 and you can get a halfway fun reliable build going for yourself. I mean where do you stop, why would you stop?, Divorce, nope keep on pumping money into the Monte, moe and more and more, okay make it $75,000

 

200k? That's a lot of miles. If you really want to, I would think of rebuilding it, as that many miles draws a lot of wear and more power could become a risk with that much wear, though it can depend on what kind of driving. 200k miles city is way WAY worse than 200k highway.

Though to be fully honest, if you want to make a sleeper I would highly recommend swapping out for a Supercharged engine as this was a factory option in 04 and 05 Montes. Not sure if the body changed to fit the Supercharged 3800 in those years, but if not then it should be a direct bolt-in. The series 2 supercharged 3800 has a much bigger following of performance parts than it's n/a version and has a greater potental to make more power.

If you do plan to go that round, I would recommend swapping the 4T65-E automatic for the 4T65E-HD, as that can better handle the power of the supercharged engine, and building it, as anything more than stock power will turn that trans into a time bomb, but it would be the best direct bolt-on, and being attached to the supercharged 3800 has a necessary following of speed parts as well. If you want your traction system to work, pick them off the same car that your trans came from, as each 4T65E-HD is not the same with different ratios per car. (I discovered that the Monte has one of the tallest ratios at 2.9 final drive).

The performance parts shop I used to window shop often was zzperformance, they have a good selection of performance parts for those engines.

Also ZIPPY02 is right about the trans, the 3800 may outlast the nuclear apocalypse if left stock (save for the plastic intake runners), but the 4T65-E trans will not.

 

I wouldn't even bother with a rebuild. I would modify how you want, if it breaks, grab a junkyard block and swap over your modifications.

These engines are a dime a dozen, and you can have a lower mileage one for pretty cheap.

 

Definitely the option I would vote for..