Gotta love the LS power

[homemade87]

I have the ls bug and never going back . I sold ever piece of first gen stuff I had . There is no comparison in my opinion . I started with a stock 5.3 in my 82 and loved it . Now I have a ls2 ( 381rwhp ) with cam , intake , exhaust . Apparently that was not enough . I have a set of gm 243 heads cnc port from total engine air flow and new cam from Brian Tooley . Goal is 450rwhp . I think when I get to that point i will be done . Yeah right .


It amazing the power you can get from these engines .

I also have a carbed stock bottom ls2/ls3 top end ( ported ) at about 600fwhp . Talk about fun to drive .

Leestruk , I know where you are coming from . I think I have gone a little farther though and having a blast doing it .

[BigRed76]

Originally Posted by slotard

The 5.3 is pretty much the replacement for the 305 so it isn't a big surprise that it's sluggish with 2.73 gearing.

You must have never owned a 305. Stock vs. stock, the 4.8 is like the replacement for a 350.

[slotard]

Originally Posted by BigRed76

You must have never owned a 305. Stock vs. stock, the 4.8 is like the replacement for a 350.

My impression is that 305 and 5.3 are the most common engines - certainly the most common V8s - in vehicles that offered them. Yes, the 5.3 makes a lot more power, but there were reasonable 305s as well.

[Daaaanz67]

DO NOT I REPEAT DO NOT UNDER ESTIMATE THE 4.8, mine runs like a beast in stock form.

[MalibuSSwagon]

Originally Posted by slotard

My impression is that 305 and 5.3 are the most common engines - certainly the most common V8s - in vehicles that offered them. Yes, the 5.3 makes a lot more power, but there were reasonable 305s as well.

Honesty however, after towing a couple times more, it is a marked improvment over the 305. However with the 2.73's and the SM465, it's like driving a Semi loaded, gotta use all the gears.

[aknovaman]

Yeh, 4.8L never put out much power and are not worth messing with.


http://youtu.be/MwJYPsJfDvE

Not bad for a 4800 pound truck.

[72MARIO]

Glad I found this post. I was worried about the truck i just bought as a doner for my 1968 Suburban. Its a 2003 with a 4.8 240000km got the complete truck for $500 delivered to my shop. Really wanted a 5.3 but the price was right and the truck has no noise starting from cold at -8. I should be able to sell $500 worth of parts off it
We do use the suburban to tow with. I figured that i will try it out and with a proper tune it should be better than the stock 327 thats in it currently.

[MalibuSSwagon]

Originally Posted by 72MARIO

Glad I found this post. I was worried about the truck i just bought as a doner for my 1968 Suburban. Its a 2003 with a 4.8 240000km got the complete truck for $500 delivered to my shop. Really wanted a 5.3 but the price was right and the truck has no noise starting from cold at -8. I should be able to sell $500 worth of parts off it
We do use the suburban to tow with. I figured that i will try it out and with a proper tune it should be better than the stock 327 thats in it currently.

That's about the amount of mileage my 5.3L has on it. Tows great as you can see, and thats on the stock tune. You should have no issue selling off $500 worth of parts. Don't forget cores! Cat converters, brake calipers, master and booster, wiper motor, all worth money at a recycler. I made $200 back on just the cats alone!

[slotard]

Originally Posted by 72MARIO

Glad I found this post. I was worried about the truck i just bought as a doner for my 1968 Suburban. Its a 2003 with a 4.8 240000km got the complete truck for $500 delivered to my shop. Really wanted a 5.3 but the price was right and the truck has no noise starting from cold at -8. I should be able to sell $500 worth of parts off it
We do use the suburban to tow with. I figured that i will try it out and with a proper tune it should be better than the stock 327 thats in it currently.

About the only thing I'd be worried about is the transmission. The 4L60E isn't known for it's longevity.

[Heavymetl]

Here's a great example of just how badly the "old-school" engines are starved for air.

Everyone knows Hot Rod does all their dyno testing at Westech, and they've recently done a couple of totally non-related articles/shows that are fairly eye popping.

Example one:
383 Chevy, Vortec Heads, 230/236 hydraulic roller, dual plane intake, carb.
440.1HP@5600 / 464.9TQ@4200

https://www.youtube.com/watch?v=L-uV61qilqU

Not a bad combo, and obviously due to the cubes excellent torque numbers.


Example Two:
Junkyard LM7 5.3. Stock dished pistons, stock 862 heads (small valve, known for being "junk" in the LS world), tiny 224/232 cam.
442HP@6200 / 412TQ@5000

http://www.hotrod.com/how-to/engine/...st-comparison/

Same dyno, incredible results. The 383 certainly made more torque, and would undoubtedly be faster in a vehicle going down the track. But for a run-of-the-mill, garden variety LM7 5.3 (I bought for for $550) with a cam change it is impressive and really illustrates how much potential lies in even the small cube LS engines.

[homemade87]

The 4l60e does pretty good if you take care of it . Most high performance mods does beat on them pretty good . Heat is the biggest killer .

Get the biggest trans cooler you can fit in there and run it thru the radiator as well as the cooler . Don't skimp on the cooler . Also if you are getting a tune get the torque management turned off or reduced . It will keep the clutches from slipping as much when towing during shifts .