what is the best chip for a 91 RS 3.1L? i want a good one that will give a HUGE horsepower gain.(if you can get a huge horsepower gain from one).any help will be appreciated, thanks.

 

You will never get a HUGE horespower gain from a chip. You will be lucky if you get a noticeable one!! The only way to get a huge gain is to do an entire ignition system, cat back, K&N filters and a chip...then you'll feel some difference.

When I had the Hypertech chip in my car, I noticed a difference, but it wasn't earth-shattering by any stretch.

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Jason E

'89 Camaro RS 2.8
A few mods....2.8 automatic with t-tops

'97 Z28 30th Anniversary
White with orange stripes (factory)
6 speed, t-tops

Long Live #3...

 

Best chip? Burn your own!

First, no one really caters to the V6s cars other than a couple "off-the-shelf" companies like Hypertech. And though I have not seen the V6 versions, their V8 versions do virtually nothing. A few degrees of spark in the lower midrange and a dash more fuel. Not worth the money IMO.

What a good custom eprom does (and this is only if you really tweak it yourself for your car) is to develop better spark curves and to fuel tables to are optimal for YOUR car..not too rich and not too lean.

I found the best power gain on my car was by controlling the knock retard. When guys get scan tools and start to analyze their engine, they are amazed on how much knock retard is really occurring and how much spark advance it is pulling away. A good eprom on a basically stock engine (ie. stock cam and heads) doesn't so much GIVE you more HP (over the stock rating) but RECOVERS what you are losing due to knock retard to get you as close as possible to its max rating.

But controlling knock retard (along with optimizing the spark advance and fuel curves) are not going to be accomplished by buying some "off-the-shelf" eprom. It takes a fair amount of analysis and "tweaking" to YOUR engine. And the only way this is accomplished is by getting a good scan tool and doing it yourself.

It really isn't that hard. Also, your 3.1 uses the EXACT system my SD L98 TPI uses. Everything I use, you can use...same eprom (I actually use a Flash Prom now, which doesn't even require an Eraser...just a "burner"), same Editor, same basic BIN.

Your are even luckier than I am as you can use virtually ANY memcal from a 3.1 V6 as a "guinea pig". Even though I use the same eprom as you, the actual GM memcal the eprom is stored is different for a L98 V8 and 3.1 V6 due to the ESC circuitry (the other half of the "chip") that is used for "limp mode".

So the real benefits of writing your own eprom is "recovering" the max HP you SHOULD be getting but are not due to knock retard, you get a much smoother running engine and you can greatly increase your gas mileage.

Check out the DIY PROM board. We currently don't have any V6 guys there to my knowledge, but the number of cylinders are irrelevant. You use the same Speed Density system I do...it just flows a little less. But what every I do to my engine, you can do to yours. Hell, I suspect that I probably convert my BIN to work for your car...though it would still need to be "optimized" for your specific engine.

NOW, if you make any modifications to your engine...then you DO want a custom eprom as it is the only way to get the FULL EFFECT of the mods you have done to your engine. And while this is especially critical for Speed Density cars since all the fuel and spark parameters are pre-determined in the "tables", MAF cars also benefit from a custom eprom too to get their "optimum" efficiency.

 

I've heard a lot from both sides about chips. I have a 91 3.1L RS as well and was thinking about going w/ the hypertech and 160 thermo. Let me know what happens if you do it.

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'91 RS Flowmaster, K&N, modified air box, Bosch Platinum +4 plugs

#3

 

Hey Jubba..I am am in Indiana too....and the 160 degree thermostat will make you burn more fuel...and your heat will barely get hot..so I would not go below a 180!

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Sgt Panther

89 Firebird..2.8/3.4 conversion

 

I've heard a lot of good things about running a lower temp thermo, especially the 160 and if I'm not mistaken, a lower temp thermo is required for use w/ the hypertech chip. I would use a 180 in the winter when I would need heat, of course I have my truck for winter so I wouldn't really need to worry about it.

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'91 RS Flowmaster, K&N, modified air box, Bosch Platinum +4 plugs

#3

 

Read some of the debates on 160 vs 180. But, I agree with Sgtpanther and perfer the 180. I should add, that until I got into prom burning and saw how the ecm uses the CTS to control so many things, I too became a convert to the 180.

 

I should add, that converting a Hyperjunk eprom to work with a 180* t-stat is a fairly easy change to do. Hyperjunk doesn't adjust any of the tables it probably should (which will make the car run better with a 160).

The only thing they do, is adjust the fan on/off temp so that your fans will always be on if you were to run with a 180* t-stat (or hotter). Just adjust that temperature, and it will work fine (actually better) with a 180* t-stat.