Is the Jet chip worth it? I have an 86 305 4bbl 5spd. Was thinking to get the stage I kit. Does it make a nice improvement? Is stage II any better? I have K&N air cleaner and hi-flow exhaust.

From what I've been able to see, it doesn't look like the module is programable. I got an hppIII for my 01 S-10 and it was very much worth the money.

I just would like to get any comments on the stage I or II Jet chip. Thanks!

 

No.

 

Why?

 

Because they do nothing. This question comes up at least once a week and the answer is always the same. WASTE OF MONEY.

Do a search on "Jet" or "Hypertech" or "ADS" and you see NOTHTING GOOD from anyone that actually knows how to burn an eprom.

There almost identical to stock except a degree or two of more spark advance in the midrange, a bit more fuel (while usually the stock eprom is alreadily overly rich) and if you have an automatic, they will lock the Torque Convertor 1 or 2 mph higher.

And if you get a lower T-Stat (usually the stage 2), it will turn the fans on a little sooner. BIG DEAL.

In fact, some fo the "off-the-shelf" chips actually will make you run slower because they have horrible spark advance curves.

Now for the worst news, custom eproms are not any better yet cost a LOT MORE.

The only way to get any performance advantage from an eprom is to burn it yourself...nothing else really works. You need to have "hands-on" access to the vehicle to program the chip to what YOUR ENGINE WANTS...not what some computer geek at Jet (who probably doesn't even race) THINKS your engine MIGHT want.

Save your money and just buy the equipment and you'll be much further ahead. Everything else is just throwing good money away.

Lastly, if your engine is basically stock, that is the BEST TIME to learn how to burn your own eprom. Don't make the classic mistake of heavily modifying your engine and now you can't even get it to run half a$$ - that is NOT the time to learn how to burn an eprom. It's already too late.

Burning an eprom is far simpler than you may think and only a little more than an "off-the-shelf" eprom like Jet. And less than a custom eprom . Sorry for the "tough answer", but you asked the question. I hope you choose to accept the advice.

 

Thanks! I appreciate the advice. Makes sense. Yea, mine is totally stock, only 76k miles on it. Just got it ispected Friday and it drives like a new car. I put allot of work into it though, it's been sitting since 92. My wifes is even impressed. Yea, I think I will pass on it. The power feels real good, but I guess I expected a bit more running 9.5:1 compression stock. Maybe better exhaust headers or som'm, eh?

I plan to keep it basically stock till the engine is fried.

 

Actually, I just noticed you have a "compucarb" model too. The eprom does VERY LITTLE for those. And very little information known about the "compucarb".

I've actualy have been contemplating developing a special BIN/ECM combo for carb cards. The carb would be controlled all manually (like a carb should) and the ECM would only control the spark tables, locking of the TCC and work with electronic speedos (if you have one).

The ECM I would use is the 7730 used in the 90-91 Vettes, 90-92 F-bodies AND millions of J & N bodies with 3.1 V6s. This would not be very hard to develop, give you complete control of the spark tables, allow you to possibly tune the carb for part-throttle by using the BLMs with a regular O2 sensor (the only reason you'd use it), control electric fans, AND if when TunerCat releases their Real Time interface for the Romulator, allow you to tune this "on the fly" with a computer.

Get a WB O2 sensor, and you would have perfectly tuned carb'd car getting the maximum power the engine is capable. (And the car would STILL look completely stock).

But now that I realize your car is a "compucarb" I wouldn't do ANYTHING other than what I just mentioned.

 

Glenn. Doesn't the "compucarb" already control spark advance and everything you listed. I know it has HEI so it must control spark advance. So wouldn't you just have to edit the calibration in the prom on the current computer in there? What benefit would switching to a 730 give you, faster ALDL is the only thing I can think of?

 

Is there an editor for the Compucarb chips yet? If so, then you could check out what it can do, but I am not aware of a bin editor for the Compucarb chips at this time. If one exists, then you should check what you can all change (does the compucarb support electric fans, locking TCC?)

Even so, I suspect the spark tables are extremely limited in their range. You could also use a TBI ECMs (truck or F-body versions) but those spark tables are limited to only 3.600 rpm IIRC.

Not the end of the world, as you should have most of the spark dialed in by then. But it would be nice to have a bit more range to play with. You can expand the rpm range of the TBI's ECMs with a patch.

But it's already done in the 7730. So I think a 7730 is simpler "replacement", but TBI would also work (especially with an expanded Spark Table).

The fast ALDL is only a factor if you wanted to monitor. Since the O2 sensor doesn't matter, could look at a WB.

 

Get a copy of the ZZZ installation manual from your GM dealer.

In it are the part numbers for the best CCC ecm, and components.

The get a copy of Doug Roe's Quadrajet Book.

Tune as necessary. I did mid 13s with a mild 350 with a Q-Jet on a cross fire manifold a decade ago.