4.8 LS need more low end grunt.

chaplinfj60 said:
so looking into this a bit more after hearing its mentioned twice in this thread. with a truck norris cam it has the potential to be as good or better than the 6.0 in low end grunt.
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Still not comparable

chaplinfj60 said:
it bumps compression up from 9.5 to 10 or 10.1 and holy crap this is serious gains i think. wow. i was reading balancing maybe needed. not even sure i have a shop who could do that or if that is even a issue
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**** that, just throw them in there it's fine
 
late to the party by 20 or so years. i knew GM did some crazy **** with these LS engine but had no idea the real only difference between the 4.8 and 5.3 was the crank and rods. i was thinking it was the size of the piston and all this other little ****. nope crazy how interchangeable they can be. blows my mind
 
chaplinfj60 said:
late to the party by 20 or so years. i knew GM did some crazy ** with these LS engine but had no idea the real only difference between the 4.8 and 5.3 was the crank and rods. i was thinking it was the size of the piston and all this other little **. nope crazy how interchangeable they can be. blows my mind
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4.8 flat tops with 5.3 crank and rods. No balance necessary.
 
chaplinfj60 said:
good afternoon all,

so this is what i am using in the buggy, beside throw it in the yard and just get 6.0 or even 5.3 what are my options to get more low end grunt. i have done the web searching and saw intake from ss trailblazer and truck norris cam. stage one i believe.

and i am ok with not making 5.3 or 6.0 power. but would like a bit more down low.

thanks
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As cheap as any LS is these days, Just swap it out for a truck 5.3 or 6.0. probably going to need some tuning either way you go.
Got both going to the crusher in my area now. can be had for less than $500 at PNP, 50% off of that on a holiday weekend sale!
 
battleborn Jp said:
As cheap as any LS is these days, Just swap it out for a truck 5.3 or 6.0. probably going to need some tuning either way you go.
Got both going to the crusher in my area now. can be had for less than $500 at PNP, 50% off of that on a holiday weekend sale!
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i get it, every day i see a 5.3 on market place anywhere from 200-1000 depending on the seller.

i like different and dont mind trying new **** out and to me 4.8 is new. will i regret it. i dont think so because everything i do to the 4.8 transfers to 5.3 on the out side the engine anyway. if it turns out to be a bastard to wheel.
 
Covecrawler said:
There are very few things that improve low end grunts.
....
Most cams, even “torque” cams are going to move the power curve up in the rom range.
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This.
A larger cam will move power band up, which will soften the bottom end. No way around that other than VVT.
The stock cam is going to have better off idle torque than most any aftermarket cam (in a stock engine).

And if the 4.8 and 5.3 use the same cam, it's already effectively 'bigger' due to the smaller displacement.

7.3 godzilla has the torques for a stock junkyard engine.
 
more and more reading it feels like the $$$ in the torque converter is about the best bang for the buck. reading more and more on the yank and very interesting reads and very cool.
 
Wfoyota said:
On the converter note for Chappy, everybody has a different opinion but spend the money on something high end and not something pre built on a shelf. Something like a yank converter will make more difference than more money put into making the motor better.
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chaplinfj60 said:
more and more reading it feels like the $$$ in the torque converter is about the best bang for the buck. reading more and more on the yank and very interesting reads and very cool.
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My 86 Squarebody has a 5.3/4L60E in it. Dana60/14bolt, 4.88's and 35's.

When I first put it together, I rebuilt the 5.3 and put a stage 2 BTR truck cam in it. Got it in the truck and it ran/drove alright. Didn't really seem like it was lacking power but also didn't seem like a giant powerhouse either. Took it out a few times and was happy with how it performed.

About a year later it put a Yank 3600rpm converter in it. That one part alone changed the truck 100% for the better. It still drives like stock if you want but you get on it and it flashes right up into where the power is at. Easily the best money I've spent on that vehicle. Wasn't cheap, think it was $1k about 6 years ago but it was totally worth it.

I wouldn't go with that high of a stall speed for something that is just crawling along though. It does make a little more heat at low speeds. For what I use the truck for (daily driver, sand, fire roads) it's absolutely perfect though. Cheaper converters are just reworked stock ones. You don't need a fancy all billet one, but a new one designed for the application is worth the extra money.

I can't explain it enough how much better/more fun that converter made the truck drive. Even with having the "correct" gears at 4.88's with the 35's, it felt like I bolted on 100hp on that first drive.

PXL_20201205_213538569.jpg
 
bad zuki said:
5.3 + Stage 2 torque cam + tuned.
It crawls fine, but has to rev up before it makes bumping torque. 6.0/6.2 has just a bit more grunt in the bottom end.
Personally I want a 454, but can't afford the axles. :laughing:
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People are bumping **** with a 22r. Could you be getting drive by wire delay or be geared too high?
 
DMG said:
People are bumping **** with a 22r. Could you be getting drive by wire delay or be geared too high?
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1. Those are normally manual transmissions
2. DBW, but the throttle curve has been tuned out. I still say that is some of the delay, but not all of it.
3. 4.3, 5.38s, 40s
 
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chaplinfj60 said:
You have all the gearing do you have an egg below? Your gas pedal and you're not hitting it all the way to the floor. Lol lol
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Yes, but I’ve always had touchy throttles, so I just plant my foot on the trans tunnel and rotate. Normally when things get technical, I’ll just use the foot brakes and no gas. It’s not terrible.

When wheeling with a 6.0 with the same gearing/tires, they foot brake/lug way better.

Knowing how I drive, this was on the floor without loading up the converter. Yes, I have water in the front tires, but the ones I’m comparing this to also have water.

 
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What about a higher stall converter? That way you're getting into the torque availability without changing stuff in the engine. I didn't see what trans you're working with though.
 
You're not going to bolt torque onto a small displacement 9.5:1 truck engine. Torque = cubes + compression.

Also, I'd rather have a slightly loose converter than one thats too tight in my experience.
 
BustedCrank said:
Could always get a used m90/m112/whatever and use a holley lower manifold, and one of those sws motorport kits, or something of the like.
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Not sure this would help off idle torque. Yes you can have full boost by 3k rpm, and they have the bypass valve that when shuts gives 0->full boost instantly. But paired with an auto trans, I dunno.
 
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