What is a safe and reliable cam shaft upgrade for a bone stock 350ci SB? I’m talkin brand new with flat tapets and piece rear main seal. How much horsepower can I expect to gain for a couple hundred bux?

While I’m in there I may as well add hydraulic lifters. Any ideas for those?

 

What year engine and what is it in? What is the intended use of the vehicle (highway, towing, in town, etc)? Manual or automatic trans? Rear gear ratio/tire size please. I'll try to give you a really good answer if you give me the info.

 

The engine will be new next year 2020 and have a SM465 manual transmission with an NP205 transfer case. It is running 35” Mickey thompson Baja claws with a 2.73 ring and pinion. I am using it for general off-roading and am looking to gain some “hard to reach” horsepower while the engine is out of the truck.

I am sending back an engine engine I purchased last year for defects I can no longer live with under the warranty and it is bone stock. The reason I am telling you this is because the normal reaction for someone to have after hearing about installing engine upgrades on an engine someone else has yet to purchase is, “ why don’t you buy it that way instead of adding it later?” Sometimes it can be cheaper sometimes it isn’t.

Thanks for the suggestions.

 

1984 Chevrolet Blazer

 

Please let me know which engine you are planning to buy so I can know what heads and pistons and compression ratio you are dealing with. Makes a difference in cam selection and other stuff.

Do you mean 3.73:1 gears with the 35" tires?

 

2.73 gear ratio at the rear differential. 35” tires and the compression ratio is 8.5:1. The current cam is .383”/.401 & 112 degrees lobe separation. 4” bore 3.480” stroke. 76cc cast iron head chambers.

these numbers will not change if I get another motor or not.

 

A little off the topic of a cam suggestions, but 2.73's with 35's has to SUCK! I have 33s with 3.73s in my K5 and it's ok with a stock 350; a bit sluggish off the line, but rolls down the road decent enough. It is just my hunting truck anyway, but I certainly wouldn't want to run it with 35s and 3.73s.

Anyway as far as the topic at hand is concerned, my suggestion is and always has been to talk with a cam suppliers (yes plural, call/email as many as you can think of Comp Cams, Lunati, etc) for cam recommendations to fit your particular application. They are literally experts where we are simply end users. There are a TON of options they can play with to make the most of the other parts that are on the engine (intake, carb, heads, exhaust to name a few).

 

I doubt any aftermarket cam is going to increase low-end torque enough to make any difference with those gears. In fact, they'll probably make it worse.

Do yourself a favor and change the gears. The thing will probably feel like a rocket with 4.11s after driving it with 2.73s. 4.56s would be even better if you had an overdrive transmission, but they're a little too low for freeway cruising with 35s and an SM465.

 

Wow an admin and senior member ganging up on the new guy. Must have done something right!

 

Ganging up on you? What are you talking about?