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Discussion Starter #1
I have the cooler thermostat and hsrk. Lots of black stuff inside my tail pipes. This is coupled with the superchips cortex. I took off the hsrk and my mileage went up and most of the black stuff went away. the still slightly rich condition is probably due to the cooler thermostat.

if you have a special tune you probably can correct for this. but if you have nothing or a superchips cortex tune the pulse of the fuel injectors will be too long and you will run rich.

in a sense a trade off. timing may not be pulled. however you will lose power as unburnt fuel may be passing out your exhaust.

what say you
 

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I think you're really reaching for a conclusion by making a deduction on the cooler thermostat & HSRK. I think the stock computer tuning can easily compensate for these two minor mods.

If you feel strongly about it though, I'd like to see more data examining the mpg setup either way.
 

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I can haz Horsepower?
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I would keep the HSRK and the stock thermo, but that's just me.
 

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Yeah, 160 is too cold IMO.
 

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I have the cooler thermostat and hsrk. Lots of black stuff inside my tail pipes. This is coupled with the superchips cortex. I took off the hsrk and my mileage went up and most of the black stuff went away. the still slightly rich condition is probably due to the cooler thermostat.

if you have a special tune you probably can correct for this. but if you have nothing or a superchips cortex tune the pulse of the fuel injectors will be too long and you will run rich.

in a sense a trade off. timing may not be pulled. however you will lose power as unburnt fuel may be passing out your exhaust.

what say you
To be honest, that doesn't make a lot of sense to me. If you're running rich, the front O2 sensor is going to read this and lean your fuel trims to narrow in on the proper stoichiometric ratio. I wouldn't think any of the problem can be associated to the HSRK, especially mileage loss. However, I agree that the most likely culprit is the thermostat. It's possible the colder engine isn't having complete combustion. The O2 sensor isn't going to read raw fuel being dumped out through the exhaust and your catalytic converter might end up incinerating it, resulting in black tips and poor mileage. The O2 sensor also won't be able to modify your fuel trims properly if it's raw fuel being exhausted. I'd say put a warmer thermostat in, but that's my opinion. I believe there are probably others with a lot more knowledge in this area though.
 

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Discussion Starter #6
I do not know. I always thought the O2 sensors were to read the aftermath of what was going on in the engine and to give you a code if something was wrong. I am not getting any codes.

One thing though. When I go to the track I go early. I let the car cool down. When it is the first run my thermostat is reading the car is cold. But yet that is usually my best time! I do not hot lap it and I let it sit 30-40 minutes between runs. Yet on average when the temperature gauge reads normal, half way, my times are not as quick. Go figure.
 

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Discussion Starter #8
I believe just the opposite. As it warms up it leans out.
 

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Another reason why i never moved my factory iat sensor.

I have never seen any issues from running a cooler thermostat, but i could see running both it and the hsrk kit together causing a issue. The ecm adds fuel while the car is cold to help with warm up and the converters getting up to temp.

I have not lost any mileage with my thermostat and i am able to run about 1-4° more timing than with the stock stat.
 

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Discussion Starter #11
I was reading some other analysis's. I did a google and just wanted to see what other people and mechanics were saying. Most said the IAT if moved to a cooler area will richen up your vehicle. However if you have a custom tune I think you can have the best of both worlds. This thread was addressed to us who are running superchips or have no tune at all. Nice to hear all the opinions though. Maybe a mechanic can answer and give his/her opinion.
 

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Discussion Starter #12
r33pwrd, no worries. try running your own cpa firm, being 51 with a stay at home wife and 3 and 5 year old girls. My brain is failing as I write this.
 

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I think you're getting confused regarding the benefits of a cold intake (HSRK) and a cooler engine temp (160 tstat).

Cold intake is good, cooler denser air = more power. Cooler engine is debatable. I don't think a 160 tstat is really going to add much advantage once the car has reached operating temps.
 

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From what I have read about this (I have never run a 160 stat myself) the post above about the engine never warming up is right. With the 160 stat (or no stat as some run) the engine controller never detects a fully warmed engine and will be running richer as a result. Sometimes that is good for raw performance since you will be less likely to ping and pull timing, but general drivability and economy ususally suffer.
 

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i have both on my car my IAT is right behind the roto filter and i had a SLP 160* thermo car runs at 176-178..

black on ur pipes is prob from getting on it and ur car is gonna go into PE mode and add fuel, and who knows what AFR cortex runs...
 

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Discussion Starter #16
good point Shane. Superchips probably has it fattened up to avoid warrenty problems. thats why i said if you had a custom tune with both these mods you are ahead of the curve.

one more thing. i put it on the 93 tune. 91 octane. was prepared to get off of it. no problems. not even in 100 degree heat. ran a run without 100 octane gas. 13.85. added to gallons of 100 octane. 13.86. no timing retard or power loss on the 91 octane. I think it is because of the 3100 feet static elevation and a da of 6000. Less oxygen in the air. So less of an explosion. Less power means less octane needed. What do you think?
 

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Discussion Starter #18
so is that rich? I guess rich and the anti knock index have nothing to do with each other. Strange I am getting no ignition retard or knock with 91 on a 93 tune. Probably the elevation.
 

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so is that rich? I guess rich and the anti knock index have nothing to do with each other. Strange I am getting no ignition retard or knock with 91 on a 93 tune. Probably the elevation.
gen4 cars seem to run best at 12.5 on the street and strip it seems i try to get mine as close as possible to 12.5 on my Wb....

id be curious to see the newer SC tunes for the intakes and what not..

and really u wont pick up more power from more timing than 25 it seems.. just more chance of knock..


if ur not getting knock then higher octane fuel is really gonna do nothing for u
 

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Discussion Starter #20
found my own answer. stock is 11.3. wot is 11.8. so superchips leans it out a little to get more power.
 
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Typhoon43
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