4.3L 262 V6 questions

Hi everyone I have a 1994 c1500 with a 262 and I was wondering what would be the biggest cam I can run with only having to change out the lifters if possible. (I am not putting a V8 in this truck it's all numbers matching MK3 truck and I want to be a bit unique with the build as everyone puts the 350 in them)

Call Comp Cams or Summit, not sure how many parts are available anymore...

Alphonse Lanceleve said:

what would be the biggest cam I can run with only having to change out the lifters if possible.

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One huge enough to totally screw-up the usefulness of the truck.

Not recommended. Hot-rodding a V-6 is fairly pointless unless you've got GM resources and a turbocharger.

Make sure the engine (and the whole vehicle) is running as good as GM intended, then live with what you have. There's no easy or inexpensive way to jack up the power level, which is exactly why folks rip out the V6 then put 5.7L engines in.

Give it fertility pills and hopefully it'll grow 2 more cylinders (same stroke and bore as the 5.7L)

I was planning on doing a mild cam for my 4.3 in my 97 K1500, but decided not to for a few reasons.

1. Finding any mild/aggressive cams for a V6 is getting hard to find. I didn't want to spend the $300+ on a cam.

2. In my particular case, I have the Vortec V6 and I'd have to reprogram the computer for the new cam.

3. I'll be using this truck for towing and having a mild/aggressive cam wouldn't make sense...

Not true at all. V6’s can be brought to bear quite a lot of power, I’ve routinely gotten 300hp from the Buick 3.8 (231) with a bore, balance, blueprint, cam and carb update. The 4.1
Only needed the balance, blueprint, cam and carb. This is from an advertised 190hp engine. The Chevy 4.3 can be tuned to get its best power and torque with all the similar efficiency updates afforded to its big brother v8: ignition induction and cam. What do you want to tune the engine to do? All production car and truck engines are median tuned, so they will work across the entire line of vehicles. Also, they weren’t adjusted to meet maximum potential. As such the engine in you truck wasn’t factory tuned for a truck, by adjusting it to meet a truck over a car power needs. I’m partial to compcams, I run 268H in most of the small blocks I’ve built, including 283’s.

Schurkey said:

One huge enough to totally screw-up the usefulness of the truck.

Not recommended. Hot-rodding a V-6 is fairly pointless unless you've got GM resources and a turbocharger.

Make sure the engine (and the whole vehicle) is running as good as GM intended, then live with what you have. There's no easy or inexpensive way to jack up the power level, which is exactly why folks rip out the V6 then put 5.7L engines in.

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JonP said:

Not true at all. V6’s can be brought to bear quite a lot of power, I’ve routinely gotten 300hp from the Buick 3.8 (231) with a bore, balance, blueprint, cam and carb update. The 4.1
Only needed the balance, blueprint, cam and carb. This is from an advertised 190hp engine. The Chevy 4.3 can be tuned to get its best power and torque with all the similar efficiency updates afforded to its big brother v8: ignition induction and cam. What do you want to tune the engine to do? All production car and truck engines are median tuned, so they will work across the entire line of vehicles. Also, they weren’t adjusted to meet maximum potential. As such the engine in you truck wasn’t factory tuned for a truck, by adjusting it to meet a truck over a car power needs. I’m partial to compcams, I run 268H in most of the small blocks I’ve built, including 283’s.

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I think the deal is that you've got to spend so much money on a 4.3L or 305 to get decent numbers, but be almost there with a stock 350. With the Buick, you don't have a modern Buick V8 to parrallel the Chevy. Buick/GM stopped building the 350 Buick after 1980 and all the performance engineering went into the 3.8L. You've got to got back in time (69/70) for Buick V8 performance. Of course there are modern HiPo Buick parts but they're super expensive.... TA Performance.

Lipstick on a pig. I'd keep it original and buy a V8 truck to put a cam in.

...but...

Call your favorite cam manufacturer. They can give you better advice than us bunch of hooligans.

I've done this to my '96 C1500, it's expensive depending on how far you want to go with it. I bought the truck with a blown engine, I knew I wanted more power out of it, but also knew this was going to be my daily driver and had to be able to afford to feed it. Did a solid bottom end, upped compression a bit, gasket match port job, short tube headers, Comp 266HR cam, everything I needed to head toward 300hp. Now the hard part, maintain full emissions control (I live in New England, we have emission testing), finding a 30PPH spider injector to get the necessary fuel to the engine is difficult and very expensive, and then tuning. Throw in a rear gear change and some transmission upgrades and you have a giant pain in the ass to get everything working the way it's supposed to. With yours being a 94 you're still running TBI and OBD-1, switching to a marine intake and an upgraded injector seems to be a much easier upgrade than what I dealt with, but a few notes: I've run back and forth quite a bit with cam selection, part of me is very happy with how mine is turning out, but wonder if I should have went with the next step down (durations more like 206/210, more bottom end, works with stock fuel and tuning), might have saved me some trouble. Second, these engines don't require a lot of air- calculations showed my engine needed just under 500 cam to work properly with the modifications I've made. Resist the urge to overfeed the 4.3, it's not a 350 and doesn't require 700 cfm to get the gains you're after. These are great engines, you can do a lot with them, and in my case the difference between 12mpg (typical V8) and 18 mpg is huge, given a 30 mile trip to work everyday. Good luck!

A Class II cam would be on par with a marine cam.
If you can find a newer set of heads I'd swap them; I took a set off a 2012 and port matched for my 98.
Intake there's plenty of carb/efi available it's just preference.