Chevy, 4.3L engine, fuel injected, stock.?

Question

Is there anything that can be done to improve performance? Turbo, cam, anything?

Answer 1

Well, all 4.3's are not the same, but there is quite a bit that can be done. Crane and Comp have a good selection of cams that will work with the stock or re-flashed ecm. The 96+ vortec heads flow great, but need minor valve clearancing for 1.6 rockers or .500+ lift cams.

On of the major chocking point of the motor is the intake/injection setup. The CPI/CPSI mani can flow enough to support 300hp, but the wacky injection has a hard time tuning for extra fuel reliably (without sticking a poppit valve open). The TBI set-ups are just limited in flow. Edlebrock makes a carb manifold (3114 i believe) that fits the vortec heads, but it has provisions for fuel injector bungs. A couple guys have much success with this set-up, since the required stand-alone fuel computer and bocsh-style injectors give the most flexibilty in tuning.

The once was a turbo kit made by Mach Performance. It was very strong....8PSI intercooled with 350+ RWHP on his Blazer. But that company seems to have dried up. Homemade is possible and been done many times...but you still have the fueling issue (even more critical with boost)

Vortec and Powerdyne have Supercharger kits for the S10/Blazer, but their gains aren't stupendous. Fueling!

NO2 is brutally effective. A well cared for 4.3 can handle 75-100hp shots with some regularity and I've know a couple guys that run 125 shots on stock bottom ends at the track consistently. 150 seems to be the breaking point.

Hypertechs/superchips and all those other hand held tuners are essentially worthless for power. But they do work great for shift points/speed-limiter removal/tire size change/gear ratio change. You need a full ECM reflash.

Check out these Forum, lots of 4.3 info!

Answer 2

It all depends. A properly sized and tuned carburetor will give practically the same horsepower on the same engine when compared to a similar fuel injection system. A lot of the time the difference in hp numbers as compared to a fuel injection system has to do with the intake (like on the TPI engines) or the type/size of the fuel injection if you're looking at a TBI unit - this is why a lot of guys claim carbs are superior. Fuel injection isn't really all that complicated, especially now with the advent of self-learning FI computers like the FAST unit. The big hassle of putting a later FI engine into an older nova would have to be with reconfiguring the fuel tank to accommodate the return lines and pump, changing the plumbing as necessary to accommodate the higher fuel pressure, and adapting as necessary the wiring, transmission (later LS type engines have different dimensions on the trans mount) and the signals to your gauges. The later engines, however, have a wealth of new tech in them that makes them superior in hp and reliability/driveability when compared to first gen engines. Would it be worth it? That depends on whether you would consider the price tag on such a swap as being worth it! You could always overhaul your existing engine and put fuel injection on it - either by scrounging FI systems, or going with an aftermarket FI system like Holley sells. Then, you'll have the reliability/driveability, and you can up your horsepower numbers by looking at aftermarket heads.

Answer 3

Sure, as much as you have to spend. Cheaper stuff would be a performance chip or program for the computer, cold air intake, and a easier flow exhaust system. More expensive stuff would be to add a turbo or supercharger, but I would probably beef up the motor for this type of thing. Adding cams and doing head work as well.

Answer 4

Actually the Chevy 4.3 is basically a 350 with 2 cylinders cut off of it. There is a lot that can be done with that engine including cams, super chargers, intakes, exhaust, etc. Check out summit racing equipment.

Answer 5

The 4.3, one of the best engines GM has made. Either with or without Vortec. You should need no other improvements.

Answer 6

A high performance computer chip , check with a local high performance shop for your options.