I know you can buy a chip and programmer for Blazers, and people rather go with a programmer because it does more than the chip. However, could you buy a chip AND a programmer and have them working together? Or would the programmer trump the chip....?

 

They are both made totweak the ECU, but theypretty much cancel each other out.For example, you plug the chip in and itraises the air/fuel mixture to the point its supposed to, then you plug in the programmer and itraisesit to the point its supposed to. The chip would be cancelled out, you could take the chip out and there would be no difference.

If you have a chip thatimproves one certain function and a programmer that has a different funtion, then you could use both.The effects work together.

 

Your PCM cannot be 'chipped' in the traditional sense. It must be reprogrammed. The JET module piggy-backs off of the pcm and alters the signals. A programmer such as Hypertech would provide you some performance gain, for the same price, you could have your pcm tuned for better gains. There are many places around the US that do this... A custom dyno tune would cost you more, but would really only be necessary if you have done some decent modifications to the engine.

 

I heard that the GM dealership can do a "flash" or something to reprogram the pcm? I was also told that it was more effective with power gains than the plug and gos. Is this correct?

 

What does everyone think about a Hypertech ECU Programmer like this one? It's the cheapest I've found...and I'm broke but I'd get it for 1 MPG better
Ebay Link


fixed long link for ya - hillbilly

 

That particular one is not intended for use on your truck. You need #30024.

I am selling mine for significantly less than that, but it is already spoken for by another member.

The hypertech works fairly well, but nothing is as good as a custom tune. I'll be getting my Rainier tuned by a local shop in another week or so and I can't wait for the torque management to be gone!!

 

Swart,

So if I get my Blazer custom tuned, what are the recommended tweaks most people would want to have done? You mentioned one (torque limiter removal), but what are the other things you're gonna ask them to do? Thanks for your help.

 

The Blazer does not have any torque management to speak of so you won't have to worry about that.

Spark and fuel tables can always be tweaked for peak performance rather than the mediocre efficiency that they are tuned for from the factory. If you've done things to free up the intake and exhaust, these parameters can be tweaked a bit further. One problem with the 4.3L is its tendancy to have detonation when tweaked (heck, some do it stock on 87 octane). So you may end up having to run a higher octane fuel with a tune than you did stock. If you plan on that, you can get even greater gains out of a tune.

Your best bet is to find a local tuner shop that can edit the PCM for you. That way, if anything isn't right (ie you get detonation), then you can have them tweak it some more (for a nominal fee) to correct for that issue. I have been in contact with a few shops near me (best one that I talked with so far is over 2 hrs away - ouch...) and the going rate is about $50-$100/hr for a tune and most say it takes under an hour. They all will require me to buy them the vehicle license for their tuner software due to the fact that they don't get any Rainiers in for a tune! So the best one I spoke to is gonna cost me $100-$150... I'd really like to find one closer so if I do have any issues or want things tweaked further, I can just stop in and have it done.

 

OOK...

I plan to replace the drop-in filter with a full cold air intake system within the next couple of months. (I promised my fiancee that I won't do any more truck upgrades until after the wedding is paid for.) :-x

I'm thinking that I should first install the intake, THEN take it to a tuner shop. Do you agree?

As for the fuel -- I onlyput 93 octane in it anyway. Despite what some people say, I do feel a difference. Even with the few upgrades I've done already, this truckflies! I want to put a turbo in it, but I'm wondering if doing so will make it launch into the air...

 

While you may 'feel' a difference with 93, it is not running optimally on that fuel. Some 4.3L run more efficiently with 89 octane once they get a bit of carbon buildup in the cylinders... But that's your choice. Without proper tuning, you aren't getting the full benefit of the higher octane rating

It really isn't necessary to have the intake on before the tune. With a drop-in K&N, you've got a pretty good flowing intake as it is. Despite what many say about the intake design, it really does work well. In fact, it works much better than a rice pipe & cone filter without a heat sheild. You really have to have a very good heat sheild to have a cone filter that is as effective as the factory box with a panel filter.