If my chip calls for a lowered thermostat, and I'm still running my stock one, am I losing power and gas mileage?

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See pics @ Billy's Firebird
92 Bird 3.1L Auto
Best $750 I ever spent....
DRIVE IT LIKE YOU STOLE IT!
Kills:
93 Mustang LX (Before Mods)
98 or 99 Dodge Stratus (tough one, edged out at 40)
92 Camaro RS 305 TBI-Not too fair, his fuel pump went out 2 days later. Nice car, but not running right.
97+ Honda somethin or another...modded....kept at my door the entire way
Close Calls
94 Grand Am 3.1 V6
92 Cavalier 3.1 V6
01 Porsche 911 Turbo (Had em till first gear)
Mods-Jet Stage 2 Performance Chip, Accel Cap/Rotor, Accel 8.8 MM Wires, Accell Coil, AC Delco Rapidfire Plugs, Dynomax Catback, K&N
AIM name OVRCLCK350

 

It could make it not run as well as it possibly could if the stat is too low. Get whatever temperature thermostat the chip's makers suggest. I had a 160* in my car, and I got a 180* later, after I got my Performance Resourse chip, and it runs much better.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End

Current Mods: LT4 Hot Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

7.5" 10 Bolt with 3.42s soon to come!

 

No,

you may get more spark knock though.

 

It's not that I have too LOW of one right now. I have a higher one than what's called for. I need a 180, and I'm running a 195. I'm worried that my car may think it's overheating and lose power by making itself run lean, and I'm thinking that would decrease the efficiency, and thus, the gas mileage. Am I off base here?

 

Well, going to the 180 would make it run a little better but not necessarily make it lean out and such. Seeing as how your in Texas, i would go with the 180 thermo anyway.

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89 IROC-Z 350 TPI

-Flowmaster Catback
-Performance Resource Chip
-700R4 (Rebuilt) Too much done to actually list
-K&N Airfilters
-Ported Plenum
-2.77 Gears (not much to brag about but eh, its there)
-MSD 8.5 mm plug wires
-Problems every other day with the car (probably not a mod, but to me it sure makes a difference)

 

I'm not saying it would be leaning out switching to the 180. I'm talking about now with my 195 in there. I'm just wondering if my current (195) is hurting my gas mileage and performance.

 

It depends on whose chip it is and what they did to it. In reality, none of the "over-the-counter" eproms that I have ever looked at ever "properly" compensated for a cooler t-stat other than adjusting the #1 Fan's on/off temperature.

And that is the most likely problem you may encounter by leaving your 195* T-stat is; you fan may come on too soon and your engine will not get cool enough to turn it off. So your fan remains on all the time.

As for the "internal" adjustments necessary in the eprom to properly run a cooler t-stat, they are not dramatic with a 180* t-stat. Generally, you have to adjust the idle speed, the IAC learn temperature and a few "warm start-up" tables to ensure you aren't burning too much gas with a lower t-stat. Without those adjustments, your eprom will think it is still in "warm up" and run too rich.

This is especially noticeable during winter time and the reason many people with cooler t-stats get poor gas mileage during winter. I did when I initially went to a 160* T-stat and before I got into adjusting the eprom.

When I got into adjusting the eprom, I got better fuel economy and more consistent performance with the 160* but I still had "tuning problems" with the 160* T-stat. I found it easier to tune with a 180* t-stat, got even better perfomance and mileage with than the 160* t-stat.

But, back to your original question; your fan temperature on (and especially off) setting is the biggest problem if the eprom adjusted for the fan temp (which is generally what they only do from what I've seen).

 

Thanks Glen, I knew I could count on you.

 

Somebody asked Pat Goss last weekend and he said it definitely will. Anything to add more power to the car is going to hurt gas mileage is basically what he said.

 

I don't know who Pat Goss is, but if he thinks installing a chip will cost you gas mileage, or that running a hot thermostat will cost you gas mileage, then i wouldn't let him check my oil.
...ed

 

What's the big deal of putting the 180 in there. It only costs like 4bucks and you can install it in 3 mins. (w/out having to drain the coolant).

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Pat Hirsz
www.iit.edu/~hirspat/MyPage2.htm

88 305TBI
Mods:Hooker Aerochamber 3" exhaust, gutted kitty, March pullies, no smog, 180 thermo,
14x4 K&N, 3.42 gears,
Eibach springs with KYB's all around,
Harwood cowl hood, Z-28 wing, fresh paint(black)
120,000 miles, 5spd, T-tops
Run a best of 16.7 @85mph before gears

92 RS, 305TBI, auto, 3.08 gears, 180 thermo, glasspack (no muffler)

 

The reason the chip calls for a 180* stat is because the way the chip works. From what I understand the chip advances the timing. If your car is running to hot, you will get detonation.