Anyone will to help me pick some parts?

MSIFreak1992 · July 22, 2024

Looking to add power to my Gen 3 4.8l.

Please no hating on the little v8 :)

newdude · July 22, 2024

What are your goals? More power? Better towing? Big thumping cam?

Edited July 22, 2024 by newdude

MSIFreak1992 · July 22, 2024

Looking for power/towing more so on torque to move it, Its for a stock 2001 chevy silverado 1500. 3.42 gears. I have HP Tuners, and ready to return when neccessary, but alot of people are steering me or trying to steer me away from the 4.8l the thing is Its basically new, 25k miles and is a great motor, also I dont wanna make a whole lot of power hence why I dont wanna go bigger motor. I want to target around 50 to 100 TQ/HP

CamGTP · July 22, 2024

Easiest thing would be any supercharger, that is a instant 75+ horsepower and torque on that engine.

The next best options you have are modding the engine. Install a small camshaft, like 212/218 in size. You can mill the cylinder heads a little bit to bump up the compression ratio to gain more power too. I'd stay with the stock exhaust manifold to keep the lower end torque. And a small camshaft will work with the stock torque converter.

You might see a 40-50hp gain at peak with those mods. You'd need to do alot more to really see gains on the 4.8, but then you don't get a useful engine anymore. The peak power will but pushed way out because you'll have to spin the engine to 6,500-7,000rpm.

If the truck is 2WD, for sure swap gear ratio's. I would do 3.90's in a 2WD. If it's 4WD, go with 3.73's or 4.10's because last time I checked you can't get 3.90's for the front diff.

MSIFreak1992 · July 24, 2024

Thanks Best Advice yet. I dont wanna spend $5000 for 75hp for a supercharger doesnt seem fitting to me!
but $500 to $1000 for other mods and 50HP/TQ makes sense to me. plus 300 for tune or so. I have a HP Tuner, so I cant get someone todo the tuning for me!

Can we talk about the gears? I want to know if I can do it myself, can I change just the rack and pinion or do I gotta change it all and how hard is it on Gen 3 Trucks? its 2WD btw

CamGTP · July 24, 2024

Changing gears isn't that hard, you just need the proper tools to do it.

The ring and pinion is all you have to change, the center section can stay the same if you wanted to. Or you can go with a real posi traction diff, like a eaton tru-trac.

You'll need the ring/pinion set. New bearings and seal, torque wrench, dial indicator and a press would be handy. You can watch tons of youtube video's on it. I bet most driveline shops would charge $1,500 or more to install gears in a rear end, that's parts and labor pricing. But changing gears from those boring 3.42's will make a ton of difference in towing and getting up to speed much faster.

asilverblazer · July 24, 2024

19 hours ago, MSIFreak1992 said:

Thanks Best Advice yet. I dont wanna spend $5000 for 75hp for a supercharger doesnt seem fitting to me!
but $500 to $1000 for other mods and 50HP/TQ makes sense to me. plus 300 for tune or so. I have a HP Tuner, so I cant get someone todo the tuning for me!

Can we talk about the gears? I want to know if I can do it myself, can I change just the rack and pinion or do I gotta change it all and how hard is it on Gen 3 Trucks? its 2WD btw

Probably be real easy to find a 3.73 axle with G80 in it, bolt on and go. (Tune update of course.) 4.10 would be just as easy to do but harder to find.

The 4.8 was never a torque producer, power only really exists spinning it fast. I'd select mods to compliment that, a higher revving cam (within reason) wouldn't be a bad choice.

Top end kit, long tube headers, transmission cooler, gear swap, tune. Cam shaft selection would take the most careful thought. Lastly, depending on the cam maybe a torque converter.

For towing, the transmission cooler I'd recommend if your truck doesn't already have it an electric trailer brake controller and good receiver hitch.

Otherwise all the mods ought to make a fun little truck to drive around.