Lakeside49

I recently installed the Hypertech "Street Runner" chip (PROM) after reading as much as I could. However, not much was written about it, even on this forum. So, this is for my `82 brethren.

Admittedly, I thought it was probably a gimmick. But, right away, I noticed a very positive difference in the shift points. It was ok before I installed the chip, so it is not a `must have' if you're debating the ~$125 cost; but the GM engineers of the day were so focused on locking up the torque converter as soon as possible (over 34 MPH) to achieve their stretch EPA targets, that it causes lugging during low speed lock-up and sacrifices driving comfort. So, it now delays the lock-up until over 41MPH or longer if under acceleration per `Jim' at Hypertech. I called because I was curious. He said that they also have a different engine timing strategy. Overall, it now feels like a more modern car with much better calibrated shift points. I expected it to reduce my fuel MPG because it doesn't lock up as quickly - but, I estimate that it improved by a full, 1 to 2 MPG. I don't really care about its fuel economy, but it was a nice surprise and probably due to efficiency improvements.

Also, the shifting itself is less harsh. The transmission shifts smoother through the gears, including when you initially put it into 1st gear, as if it is delayed for a fraction of a second while things mesh, including under load. For the transmission shifting benefits alone I will never replace it with the original chip, although I will keep it on hand for advanced diagnostics as the Hypertech instructions suggest.

Regarding the higher performance at WOT... I did not notice a thing different versus the original chip from an acceleration standpoint. The car only has 46K and is fully tuned with mostly new engine electronic/drivability sensors and ignition components, so it was already running extremely well. In fact, since the transmission downshifts a little less violently at sudden wide open throttle, you might initially think it has less power at WOT like I did; but after carefully paying attention, it probably has slightly more spunk but the engine's power band is noticeably smoothed out. It seems to pull slightly harder. I like it a lot, and didn't expect to. The Hypertech guys were unencumbered from the GM engineer's EPA mandate to maximize fuel economy by locking up the torque converter too early. Dave McLellan explains their EPA-related challenges on the `81-`82's in detail in his "Corvette From the Inside" book.

Bottom line, I think the Street Runner chip is better calibrated than the OE chip without sacrificing anything. I think that it drives noticeably better. They seemed to have smoothed things out and compensated for the shortcomings of the OE calibrations applying the benefits of hindsight. I would buy it over again for the above reasons.

Installation tips: It is NOT necessary to remove the ECM as noted in the generic instructions. Just remove the car's battery and the ECM's chip (PROM) access panel is in plain view and comes off with one screw. Have a bright flashlight with you. The OE chip is in a green plastic prom "carrier" which pulls straight out and is designed to be properly re-inserted. Important!! The OE chip has a little notch on the right side of the chip oriented from when you are looking down into the battery compartment. The Hypertech chip has a notch in the exact same place as the OE chip but, on both chips it is rather discrete. It is partly hidden under their white labels, but you can see/ or easily feel it with your finger nail on one end. Press out the OE chip with a small flat object, then install the new Hypertech chip in the green carrier with the notch facing right while looking down into the battery compartment - in other words, the notch faces right if you are holding the chip up to your face and the spines are pointed at you. The bright light really comes in handy while reinserting the chip because you can then see how to line up the male spines with the female holes while inserting. (don't go there). Jiggle up and down ever so slightly while inserting the chip and carefully but firmly slide it back in. If you feel any significant resistance, pull out the chip and use a needle nose to straighten any bent prongs and try it again. I had one prong bend on my first attempt, but fixed it in a second and encountered no further issues. Just the satisfaction of doing it myself.

Note: if you ever notice that your vehicle wants to stall out on acceleration, especially over 30 MPH, and you get a Code 51 "defective Prom" from the ECM, you will need a new PROM chip. You will get this code if you install the chip upside down, or bend a prong as I did.

I'm hoping that this is useful to any of us`82 owners who have ever considered experimenting with the idea of installing a Street Runner chip.

billschroeder5842

Thanks for the write up. I've been debating performance items as I try to get my 82 running smooth-- which it does mostly..

Anything else you have tried that makes a difference? I admit that the CFI has me a bit intimidated.

Lakeside49

Good question. My cold-start and erratic-warm idle issues were resolved after I tightened the surprisingly loose intake manifold bolts and as a precaution, I replaced the headlight hoses, headlight override switch, map sensor and ECT sensor. Not to mention the fuel pump and repeated applications of premium fuel injector cleaner (3-4 bottles with 1/8 fuel tank level) To fix a slightly hard start, I replaced the ignition module, coil and distributor cap. I only did this as a precaution on a 34 yr old car since only the tires, hoses/belts were not original - but was unexpectedly amazed to see it's noticeable positive effect on how quickly it started up after the parts replacement.
I am going to regret saying this because there is no wood around me right now to knock on, but this car is running like a new car now. The slight bit of idle loping is probably due to the cam and higher, 9:1 compression ratio that was unique to the '82 - and, it sounds cool at a stoplight.

Should mention that, when I pulled out the EMC (because the GM shop manual incorrectly directs it when replacing the prom chip), I also replaced the electronic spark control module (while you can still find them) and the fuel pump relay that are hidden behind the ECM for precautionary purposes. I plan to forever keep this wonderful car and don't want to get stranded somewhere in the future when old, grumpy and decrepit - and, not just my wife, cheers!

Mountainoakie

The ECM/PROM in an '82 does not affect the shift points in any way because they are determined by the amount of TV spool pressure and the mechanical governor. Your shift points may have seemed to change but they really didn't. Sorry.

Lakeside49

Thanks - I'm working on my layman's trans-speak, and pulled out the shop manual to prove it. The `shift lock-up points' are now noticeably different. The ECM controls when the torque converter locks up (shop manual attachments - notice the wires coming out of the transmission and reference to ECM control of the entire lock-up point) which, I very pleasantly found out has a major impact on the driving experience. The chip fixed this.

lionelhutz

Agreed, so there's no reason shifting out of park would be better and the only reason that shifting from 2-3 and 3-4 would be smoother is because the torque converter isn't locked up.

The torque converter lockup isn't a shift...

Lakeside49

Yep - it puts the "lock up point" (which feels and sounds like a gear shift event in the seat of your pants, and it is ECM chip controlled) in a much better and more normal feeling place at 42 MPH vs 35 MPH contributing to the noticeably improved, modern driving experience. Between that worthy improvement and whatever they did to the timing strategy it feels noticeably better when driving it around town. I'm hoping there is no unforeseen mechanical or electrical system downside though I can't think of any by reading through the shop manual.

lionelhutz

No, overall the chip only does some minor tuning changes so it won't cause you any long term mechanical or electrical issues.

COOLTED

I had a Hypertech chip in a Trans-Am. Freed up power and eliminated the top speed limit. I also liked the changes to the transmission.

Rmodeler

Do you need to use premium fuel with this chip?

Lakeside49

It looks like Hypertech has two options for the `82. They are around the same cost. The "Thermo Master" looks to be the higher performance rated chip and requires a different thermostat and premium fuel. I'm not into that stuff. The Street Runner, which I decided to install is apparently tamer and requires neither; though I have read and will heed that premium octane fuel is still suggested to maximize the benefits of the chip.

74 LS4-454

I also have a Hypertech Chip, but it's still in the box. I have never installed it, mostly forgot I had it and just never got around to doing it. As I used my 82 as my "dd" for almost 4 years, I determined the best way for me to enjoy the most out of the motor, was to keep the trans in "D" local around town. Only used the "OD" above 45 mph and up to speed on the highway. That way I didn't have to deal with really low r's in everyday driving. And if I was coming off the highway, just downshifted for the drive home in stop 'n go, and never felt the engine lug or feel sluggish.
Just a fun car to drive, maybe someday will install the chip, but for now with the other two, they are keeping me busy...... Tom