Engine Upgarde
 

I have an 06 LT with the 3.5 engine in it,automatic trans.
I was think ing about upgrading to the 5.3,Any idea about how much this would cost?How much would it hurt my gas milage?And if it really worth it?

I know alittle about cars but not to this extent.
Any help would be appriciated.

Thanks

IMO, if you don't know a lot about cars, but want the 5.3L, I'd probably just sell your car and buy a used one. Not only will you get the engine you want- but also a lot of other upgrades too along with stock reliability.

Gas mileage will obviously be worse than with a 3500- it puts out significantly more power and is a much bigger engine.

The cost is hard to figure because it really depends on how much you can pick up a powertrain for (try searching online for prices like ebay and such). I've heard people get a complete powertrain for $1500 (higher mileage), and I've seen some on ebay for $5000- there doesn't seem to be as much of a set price as there is for more common engines like the 3800s.

Since the powertrain will be over half of the swap cost (unless you're going to have to include labor too)- I'd probably take what you pay for it, and double the price. You'll likely have plenty of money leftover- but at least you'll be able to safely get it done.

Also, I would not do a swap like this if this is your daily driver, and only car. You need to have something else to drive in case you run into a big snag. This is true for any engine swap IMO (even the L67)- but its much more important with an engine like the 5.3L thats been swapped so few times- you'd be a guinea pig for the most part.

Thanks it was just a thought,somethin to i was curious about.Way too much money.i could get everything else done i want for that price.

yeah i agree with bumpin96monte. if you want the V8, go out and buy the whole car, then you have all the other upgrades that come with the SS monte anyways: bigger rims, bigger engine of course, beefier suspension parts, HD transmission, badging, plus the piece of mind knowing everything is where it's supposed to be without worrying if something is installed incorrectly.

Heard the 5.3 V8 gets 18MPG city (if you drive it right) and 27MPG highway. If you have the 3.5 you should be getting 20-21MPG city, and 29-30MP highway, so there's not much of a loss in fuel economy, (again, if you drive it right). It'd be a new thing, probably never done before, to drop a 5.3 in an LS, but like the other members suggested, so many other things would have to be upgraded. If the 303HP looks enticing to you, (as it does me) I'd just save up for a used Monte SS, or maybe the new Camaro SS 426HP, or the 2011 Impala SS 500+HP. There are better, more reliable options if you're after the big V8 power. But don't think you're the only one, I had a dream of dropping a 5.7 liter V8 LS1 engine in my Monte, nothing like the sound of a LS1. But SO much drilling, cutting, moving engine parts around has to be done, it's not remotely realistic unless you're insanely rich.

am i hearing right quarter????? 500+ for the impala ss??...rwd? its not the ls7 is it?

That's what I've heard. I haven't researched it much myself, but a lot of people are talking about GM redoing the Impala SS in 2011, giving it RWD and 505HP I believe. They might want to upgrade the Camaro SS from its meager 426HP at that point.

Links / Pictures or it didn't happen.

I hope you aren't reviving the OLD rumors of the Impala becoming the G8

1) I've only gotten close to 18 with mixed in highway driving. Never going to get that in strictly city cruising, I can normally get 15.5-16 MPG on a given tank in the city. And once on my way home from Wisconsin Dells, WI I got a smidge over 28 MPGs, all highway. DOD is made for highway, it doesn't do crap in the city.
2) Wrong, never going to happen.

Its hard to really say exactly for any car (thats why they post a range on the sticker too for each)- because one person doing "city" driving through a major downtown city- stop light to stoplight, and sitting in backed up traffic is going to obviously get much worse than someone in a rural area with more spaced out lights, and without all the traffic.

Personally, on my 5.3 GXP- I have been getting 21.1 MPG that consists of about 98% city driving (the last 1/2 mile or so to work it a 55 mph highway). I've never went through a full tank on the highway, but from the little highway driving I've done, it seems to be about 29-30 mpg.

In comparison to my old L67 GTP on the same route, my city MPG was about the same- peaking about 22 MPG, and my highway was about 32 MPG (the car was just a 3.4" + basic bolt ons + a tune).