perico8

starting this off i have a 4.8 in my 07 nnbs silverado looking to push more horsepower i have slight knowledge in this but id like some advice from people who know or have built some of these engines don’t want crazy numbers right now just want something fun i can run at the drag strip with some buddies (i’m looking into a hi lift stage 4 tsp cam with a 3200 stall and 4.56 gears) that’s where i’m at right now with my plans if anyone can reply and help i’d appreciate it thanks 👍🏽

Full Power

My advice: DO IT !
4.8 love to spin. 4.56 gears will make big rpm.
Run EXACTLY the valve springs recommended by your CAM Grinder.

Kjduvall

i had a 08 rcsb 4.8 and yep they love to rev. go bigger on the converter 3600 min 4000 would be great, dont go cheap on it do yank/circle d/ or fti and a tru cool 40k cooler. while your in there a new rear main seal, billet oil barbel and maybe a better flex plate (summit has a sfi house brand for cheap. next up a set of tsp 1 7/8 headers to a speed ing true dual dumped exhaust set up (if you like it loud). get the tune spot on and go have fun. later down the road you could add a cheap nx proton shark nozzle kit in the intake pipe and some colder plugs for an extra 50-150 hp.

68Formula

If you're still running stock compression ratio, the TSP Stage 3 Truck high lift would be a better fit Going with the Stage 4 on a 4.8L, you're only going to gain 3-5hp above 6500rpm with a big sacrifice of mid-range and low end. And you'd really need at least a 3600+rpm stall. The stage 3 on the other hand, will work great with your gears and the 3200rpm stall. Or split the difference with Summit's SUM-8720R1. In a 4.8L (important to qualify that), it makes the same peak power as much longer duration camshafts, but with a lot more low and mid-range. You'd literally be faster in a 1/4mile with either of those 2 camshafts, then you would the Stage 4.

Speed Engineering has some inexpensive stainless headers. Their 1 3/4 would be a good fit for the 4.8L. The rest of the exhaust is large enough to it can support the hp with just a Borla muffler upgrade. Or if you really want duals , Speed Engineering has those as well.

perico8

ok probably going to edit the cart because id rather have a good low end to mid time i dont see myself doing much roll racing thank you

perico8

hows this cart?? looking for a good 1/4

Kjduvall

summit has a house brand sfi plate for way cheaper, and im not sure you need a vvt kit my ly2 4.8 didnt. i just used a different sprocket 1bolt to 3 bolt for cam change. you might want to look into what 4.8 you have. if its a ly2 its got 799 heads and the tbss intake on it stock. (the reason i recommend a better flex plate is ive cracked 2 of em around the mounting bolts)

G Atsma

NO 4.8 came with VVT or AFM/DOD, so you can delete tat from your cart.

perico8

yes it’s a ly2 with the 799 heads so i’ll take off the vvt delete kit and get the other sfi plate👍🏽

68Formula

Skip the LS9 gasket. It's popular for those trying to save a few dollars and plan on using boost, but not a good choice for a 4.8L N/A. It has a very large bore size even more thicker than the stock 4.8L gasket, giving a large crevice area and poor quench. Plus you could use all the compression you can get with that camshaft. Find a gasket that is .030" to .040" larger than the bore. And then measure how far above deck the pistons sit and then choose a thickness that gives you a .036-.043" piston to head depth. Both the improved crevice, quench and slight bump in compression will help make the most power.

Cometic makes a number of MLS gaskets for the LS in many sizes, so you should be able to find something very close. And you can use Summit's website to easily filter by engine type, bore, and thickness, and MLS to quickly find the one that is the best fit regardless of brand.

BTW, you'd have to purchase the pushrods separate, but even after adding them, the Summit Racing Cam Kit is a lot cheaper:
https://www.summitracing.com/parts/s...olet/year/2010