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Budget 4.3 Vortec tips and tricks.

388714 Views 44 Replies 33 Participants Last post by  greendeh
Howzit,

For those of you who have a 4.3 Vortec and are looking for some cheap or free power, I'll share what I've trialed with. I have a 4.3 in my sierra and it was pretty sluggish when I got her, especially going from a V8. So here's where I started:

- First was the exhaust. Now you can go on craigslist or to your local junk yard and see if anyone is selling any after-market dual systems and mufflers. I decided to go cat back with a custom system that cost me 400 big ones. Ouch. If you shop around on a budget, you can find pretty much everything you need for a cat-back system for pretty cheap. It will add some power and make your ride sound a bit better. It still will sound like a V6 when you mash it, but it's better than stock.
If you got the money, you can go with a full exhaust system with JBA headers, high flow cat, and your choice of after-market mufflers and pipping.

- Next, I descreened the MAF sensor. Just remove the intake plumbing from both sides of the MAF carefully, remove the 4 outer Torx head screws from the MAF assembly, pull off the side that has the honeycomb, and set the rest of the assembly carefully to the side. Now take the honeycomb piece and firmly press around the edges of it. It will make a crackling sound as it separates from the rest of the housing. Toss that honeycomb piece in the trash, reassemble the MAF, and put it back into place. You will notice a slight difference in acceleration with all the extra airflow and best of all, Better MPG. Just with a tune-up, dual exhaust, and descreening of the MAF, I noticed a huge improvement in my MPG. So don't waste money on those expensive ones when you can do it for free.

- There is a baffle on the throttle blade inside the throttle body. Remove the air intake off the top of the throttle body. You will be able to see the throttle blade inside. If you open it, you can see the baffle on the bottom front of the blade. Take a Torx bit screwdriver and remove the 2 screws that hold the blade in place and remove the blade carefully. Take a Dremel tool and cut that sucker off so that the blade looks like a normal blade or a coin. Be sure not to mar any edges of the blade, or it will mess it up. Reinstall the blade and intake. Now you should notice even more difference in some throttle response.

- Install some iridium spark plugs. These actually do have more efficient sparks which provide some power, better emissions, and better MPG.
UPDATE: Just replaced the iridium with regular ACDelco Platinum. The iridium was causing too harsh of a detonation therefore in cold weather and start-up, they were making the engine hesitate. When I pulled them, they were also coated with charred soot. Too powerful a plug. The platinum work more efficiently with a smoother mild ride. The truck is a lot quieter as well and not as jarring on throttle response.

These 4 things above that I described actually work with boosting your MPG. I tried it and it helped a lot. The throttle response was much better as well. Throttle response should be the first thing to improve before trying to improve horsepower on these engines as well. The next things below I will mention gave me more power and quicker acceleration but totally bombed my MPG.

- Cold air intakes can be expensive as hell. You can actually go to home depot and get all the pieces for really cheap, except for the cone filter. So if you can, do that. Or you can do what I did which is find in sys-USA on eBay, and they sell the cold air intake for the 4.3 for only $65. It's well worth it. especially after all the other ones are like a couple hundred. You will notice an increase in response, BUT, your MPG will go down, depending on what element you live in. If you live in a cold climate, your MPG is even at greater risk since even more mass of cold air is moving through the intake. The reason being is that there is an intake air temperature sensor (IAT) before the MAF. The IAT gathers info on the air temp and sends it to the ECU. The ECU then figures out how much fuel to deliver and spark timing so it can efficiently run at any temperature. So when cold air hits the IAT, that's a lot of dense air going into the intake. A huge mass of dense air mixed with a lean mixture of fuel = bad detonation in the cylinder. So the computer sends more fuel to each cylinder when the air is super cold. Thus dropping your fuel gauge. So I would wait to put on a cold air intake until the warmer days of the year. But if you live in hot climates, feel free to put it on and leave it on all year round. It does help pretty significantly with power.

- Power adders and stupid resistors on eBay. Ok, stay away from those scams. Those guys sell people a 20-cent resistor, tape it to a piece of paper, or put it in a pretty box, and charge you like $15-even $89 I've seen. Don't fall for it. If you want to give it a shot and know what it's all about, I'll explain how to do it and what it does. As I explained in the last paragraph, the IAT reads the air temp and sends that info to the ECU which in turn adjusts fuel and timing accordingly. So, these "magical" resistors are actually 4.7k ohm, 1/2-watt resistors that you can get at Radio Shack. They come in a pack of 5 for just a buck. Take one, some electrical tape, unplug the IAT cable from the sensor that's located on the intake tube before the MAF, bend the 2 ends, 2 times so the ends are a little thicker, then bend them so they can fit into the 2 holes in the plug. Tape it together so it doesn't fall out and tape it to something secure. Ok, what that does is in a nutshell, it makes the ECU read that the air coming in is 52*. As explained before, cold air means more fuel in the cylinder. If you just unplug the IAT, your CEL comes on and that's never cool. The resistor MAY add maybe just a little power, but I highly doubt it. I suggest don't try it with a cold air intake. Try it with the stock induction only. But please don't waste your money and fall for those clowns on eBay.

- Power-tuned ECU. I have heard mixed comments about handheld programmers and such. It sounds pretty good with certain ones. If anyone has tried any with a 4.3 Vortec and Actually had some good results, let us know. There are other options as well which could be cheaper and more beneficial in the long run. Take your vehicle to a shop that actually does tuning in-house with tuning software. Or there are the three companies that most of us come to love such as, Wheatley, Blackbear, and Wait4me. Those guys will bring out the very best in your vehicle, 4.3 or not. The price is a hell of a lot cheaper as well, going dollar for horsepower.

- Throttle body spacers seemed to be all the rage for a while, then nothing. I purchased one, but have yet to put it on. I have been hearing mixed reviews about them. I was told that if you have a carb or TBI, a spacer is more beneficial because the fuel follows the air into the intake, therefore, creating a bigger combustion. Has anyone actually tried a spacer on a newer Vortec? If so please let us know the consensus.

I hope this stuff has helped you guys a bit with your 4.3 Vortec. These tips you can also use on pretty much any other engine, but I know how much the 4.3 guy wants just a little more kick out of their machines. If anyone had anything to add as well that will help us all out, please feel free. I hope this works out for you and if you guy has a question, just ask.

Mahalo.
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Hey, thanks for the tips.
Solid post, that had excellent information and good detail. Well done. Any idea how much of the specialty mods apply to the 2.2 liter fours?
4.3 mods

Mike - how much MPG's did you gain from de-screening your MAF? Has it caused you to throw any codes? How long have you been running your truck with the de-screened MAF? You also talked about working on the piece on the bottom of the throttle body plate. Can you give a better description of what it should look like when you're done? Did this help with your MPG's? Feel free to drop me a private message if you want to.
Solid post, that had excellent information and good detail. Well done. Any idea how much of the specialty mods apply to the 2.2 liter fours?
I wish I knew, but I have no experience with the 2.2 4 bangers. I assume the basics will help like what I have done, but I don't know for sure.
i have a throttle body spacer on my 01 chevy with the vortec 6.0. it made a very noticeable differance in throttle response and added a little low end but not enough to make a big deal. it is just a poweraid throttle body spacer.
i have a throttle body spacer on my 01 chevy with the vortec 6.0. it made a very noticeable differance in throttle response and added a little low end but not enough to make a big deal. it is just a poweraid throttle body spacer.
Awesome, thanks for the tip. I have a TransDapt spacer that I have yet to put on. I might go ahead and try it.
what year 4.3 are we talkin here? Will these tips work on an 09?
Im pretty sure the Vortec 4.3L is the same. However on the 09 i am pretty sure that you will void your power train warranty by messing with the intake. Not 100% though.
Im gonna be trying a few of these tricks on my 97 blazer.. Im getting about 22-23mpg now.. Thats doing 65 on the interstate for all of you who think that number is high.. Hmm can i see 25 on the horizon.. We shall see...
Hey Murdog94 - After you're done with these changes, will you post your results and what kind of MPG increase they produced. Be sure to include any tips or tricks that help the job go smoother. Are you going to make all the changes at once or do one at a time to test the results?
Goldie
im gonna do it as the budget allows.. since i am also returning my 1988 K2500 to the road after years of neglect from the previous owner...
would these tricks work on an 06 4.3 no vortec?? also where do you start with the maf sensor and the baffle in the throttle body.
@ Lancer, all 4.3 silverado motors are vortec, its just a name really but yes please if anyone has tuned a 4.3 or installed a throttle body spacer, let use know!! Better than spending hundreds of dollars for nothing. Also I heard that they make a camshaft for the 4.3 that adds at least 40 hp but thats alot of work for only 40 ponies..
Well, I have the 4.8, but I do have a TBS, and I absolutely hate it. No power gains, no MPG gains, and an EXTREMELY annoying whistle sound on acceleration. To me, if you want to make your truck sound like it has a really weak turbo, install it. Otherwise, give it to charity.
Im pretty sure the Vortec 4.3L is the same. However on the 09 i am pretty sure that you will void your power train warranty by messing with the intake. Not 100% though.
Im gonna be trying a few of these tricks on my 97 blazer.. Im getting about 22-23mpg now.. Thats doing 65 on the interstate for all of you who think that number is high.. Hmm can i see 25 on the horizon.. We shall see...

The true Vortec 4.3 came out in the mid to late nineties. One way to tell is by the casting numbers on the heads and block, you can google them to find out. What is the most obvious way to set the true Vortec apart from the older versions, if you have the heads off, the valve shroud on the older 4.3 is bean shaped. The Vortec is more heart shaped. This allows less displacement in the true Vortec heads for better compression.
Update,

Hey guys, glad to see your still at it. Sounds like some have had some good results so far. About the TB spacer, don 't do it. It was a huge waste of time, patience, and money. Also as for all the mods as mentioned, my truck now hates cold weather. So keep in mind your truck will not like cold weather once you complete these mods. The best thing to do is to just start it and let it sit till it's at full operating temperature. Once it's at full op temp, you will be good to go. So far I'm pushing a little over 18 mpg, and that's doing 80 mph on the hwy as well as stop and go town traffic. Not sure if I mentioned yet, but the iridium plugs are an absolute evil for that little engine. They cause it to detonate like crazy on cheap gas. My remedy for that was single electrode platinums and I run the high grade gas. High grade gas is a lot better on your engine. Low grade causes detonation which cause corrosion within the engine and is very harsh on it as well. If your on a budget, I would do high grade every other tank full.


As for knowing whether your 4.3 is a Vortec or not, the true Vortec came out in the mid to late nineties. The older 4.3 heads have a bean shaped valve shroud, and the Vortec has a more kidney shaped valve shroud. It allows for less displacement which in turn allows for more compression. You can also check the casting numbers on the block and heads and google them. The older Vortec 4.3 before the mid nineties were named so because the type of intake that was used. It had created a "vortec" like effect inside the intake, that's all.

Does anyone know where to find full rebuild kits for a '98 4.3L Vortec?
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Hey Mike! Have you had a chance to get any photos of your mods yet! I'm about ready to start on the the throttle blade part.
Goldie
Hey Mike! Have you had a chance to get any photos of your mods yet! I'm about ready to start on the the throttle blade part.
Goldie

Yeah I apologize. I been really bad about that, although I also do need to find my camera. How has the programmer worked for you?
ScanGauge

Thanks for the up date. The scangauge I mentioned is not a programmer. It monitors your driving parameters and allows you to adsust your driving habits for the better fuel economy. There are number of ways to set this up from instant mpg readout to ...you name it! It has been a real help for me to keep my foot light! This time of the year I can usually make 25-26+ mpg. Winter driving (and winter gas mix) drops it down to 22-24 mpg. Drop me a PM if you have any questions. Or take look at the cleanmpg.com site.
Goldie
Runs like crap

:grrrrrr: guys just need a little help i followed the advise,removed the MAF honey comb screen off, and cut the throttle body baffle ofF the buterfluy, know the engine seems to serge and has less powre, and worst off the gas milage has gone down>Does it need to be reatimed know that its breathing better? these tips are going to cost me over a 150 bucks for a Maf and of coures the wrecker wont sell just the buterfly buy its self so i have to buy a hole throttle body any help would be appreciated
INFO
2000 sonoma 4.3 vortec 2 wheel drive SLS with spyder injection
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