Got a 85 tpi with usual free/low cost mods(gutted air box with k&n's, maf screens & fins removed, "modified" cat, timing bumped,92 octane, 160* thermostadt with cooling fan on toggle switch, bosch 4's, airfoil,etc). Would a Hyper-tech chip make a worthwhile performance improvement? Whats the diff between "Streetrunner" & "Thermomaster" chips, and cost. Are they worth the $$$$. Let's hear what you got to say. Thankx.

 

i have the thremomaster im my car and i cant feel any real performance increase. a guy iroc-zpost.com had the street runner in his and he lost a few 10th's in is ET. the reason i got the chip was to keep the engine running cooler and it does a damn good job at that.

 

My Thermomaster made no SOTP difference. Didn't take it to the track to test it, before and after kind of deal, though. I don't know if it runs cooler because of the chip or because of my 160 thermostat and fan switch.

 

It runs cooler because of the thermostat not because of the chip.

 

But not as cool as you John.

Actually, I thought on TPI with the dual fans, one of the fans is controlled by the ECM, and some aftermarket chips do turn on the fan at a lower temp.

Anyway,

I've read so many GM High Tech Performance mags that had a lot of cars with the basic mods that we do. You know, chip, cat back, airfilter, maybe even headers......

They all picked up ET by switching back to the stock ship and advancing the timing a few notches.

Had something to do with the aftermarket chip having a fixed fuel map, and the stock chip is more forgiving......or something like that. I'd have to dig it out to find it, then read it, then post it on here......that's too much like work.

Just take my word on it (and about 70% of the folks on here). I'm about ready to pull out my Jet Stage2 chip. I didn't notice any performance diff., but it sure sucks down the petro more.

AJ

 

so....I'm planning on getting the chip for the reason of beiing able to run a 160 thermostat. should I have one custom made with all of the stock info cept fo the thermostat? if you have time you can email me at hiperf2002@yahoo.com thanks

 

Before you spend almost $200 on that chip I would suggest you check out this subject in the Tech Section: https://www.thirdgen.org/newdesign/tech/cool.shtml. It sounds like you might be alittle confused and I don't want to see you waste your money I also got this from the FAQ's section from here on the site. It states as follows:

Q: What will effect will installing a 160 degree thermostat have on my TPI engine?

A: What effect the 160 stat has on the engine/computer depends on different factors. In terms of achieving closed loop operation, the oxygen sensor plays a more important role - it will not function until the exhaust temperature is at least 660 degrees F. To a degree this is a function of the coolant temp, so it is possible that abnormally cold coolant temps can prevent closed loop operation.

If the coolant reaches 160 degrees, there should be no problem, as the torque converter lockup AIR, and EGR function at temps over (approximately) 150 degrees F. The trouble is that overcooling (and subsequent chronic open loop operation) is much more likely with the colder stat, since you are running that much closer to the "crossover" temp. This is especially true in colder climates, where the ambient temperature can contribute to the overcooling problem. A 160 stat is probably not a good idea if the ambient temperature is below 75 degrees F, or if a significant percentage of the driving time is spent on the highway. In that case, go with the 180 instead.

Aside from loss of converter lockup, AIR, and EGR operation, overcooling can cause an abnormally rich air/fuel ratio, which at best will make your fuel economy and performance suffer, and at worst will destroy the catalytic converter. In any case, the colder stat is not much good without changing the temperature at which the radiator fan activates. During city driving, the fan will simply wait until the coolant reaches 225 degrees F to turn on, which is what you were trying to avoid in the first place.

I'd suggest getting a 180degree thermostat and a fan switch. I hope this helps! John

 

Hypertech, Jet, ADS, etc, none of those generic chips are worth the price they charge. Do a search, and you'll see. This topic comes up all the time. The only thing they change is a little more timing, and turn the fans on sooner. You can do the same thing by advancing your distributor a few degrees, and installing a colder thermostat and fan-switch. Save your money.

 

This is simply in reply to whether or not the chip is worth it. No. I bought the Thermomaster and couldn't tell any kind of difference, except that I could see my fuel gauge move towards "E" when I floored it. Maybe it did pick up a few hp, but I haven't had it dynoed, and it wasn't worth the $130. The Thermomaster also requires 93 octane, so if you only fuel it with high octane gas when you plan to race, you're outta luck.

 

The problem with those eproms designed for a 160* T-stat is they generally ONLY alter the fan enable temp setting. But they don't adjust other tables that are crucial for getting the right mixture. Without those tables also changed, a 160* t-stat will make the ECM think it is in "warm up" mode and thus cause you to run overly rich.

I have ran every type of t-stat at one time or another. Though I haven't burnt a custom eprom for a 195*, I can say that I preferred a 180* (with appropriate changes in th eprom) to a 160* (with the proper changes). I found it far easier to get the performance to be more "consistent" with a 180* than a 160*. The 160* was just not as stable. Also, those extra 20* sure are nice during winter.

But, the bottom line is, I can get the same performance with a 180* (with proper changes in the eprom) as a 160* and it will do it more consistently.

I should add, that Grumpy (Bruce) has also tried all the different t-stats (with appropriate changes in the eprom) and gets the same performance running a 195*, but with even better consistency. So the key to power is proper tuning of the eprom, NOT running a lower temp T-stat.

 

Like mentioned, one requires the use of a 160 thermostat and the other does not. Forget either one. Get one custom burned to your exact modifications. The programming of the HyperTech chips (and Jet also) are generic. You will see more of a gain with a custom chip.

 

I just read in GM High Perf, that the hypertech chips lean out the mixture at WOT compared to the stock chip. I have had a themomaster for years and I am going to pull it because I have always run lean to the point where my exhaust valves were bright red. if you do any mods that enhance airflow DONT get an off the shelf chip because they will be lean at WOT.

 

Yeah, in case anyone is interrested I just got a reply back on the e-mail I sent Hyper-teck. They "claim" I'll get 15-18 hp. & 20 ft;/ lb torque.increase with their chip on a 85 TPI. Any opinions:?

 

i just installed a JET stage two in my 85 IROC two days ago, it was worth the $40 i payed to get it new off of ebay , but i didnt notice a huge difference in power, i also installed the 160 t-stat, i have a fan switch wired up aslo, but since installing the chhip i havent had to turn my fan on. because if i run my fan, my car runs @ 110-120 degrees, and that badly cuts into your performance, and gas mileage. If you can find the chip cheaper like i did, then its worth it, but i wouldnt recomend spending $220 for the stage ll when there are much cheaper things that give more HP

Caleb