why colder stat and plugs?

[Donald]

Why run a colder stat and plugs with the Reinhart chip? Does that not make the engine think it is in warmup mode and keep the fuel mix richer?

How about running chip only?

[tetsu]

Cooler stat keeps the engine cooler cooler = denser air charge = more power.

Cooler plugs help prevent ping which activates the knocksensor which kicks back your timing and kills performance to avoid detonation.


Did I miss anything?

Johnny

[SergntMac]

nope, except that were talking only 8 degrees on the stat...

[03 Merc]

Any particular reason it is only a 8 degree change? Or is that all that's available? It seems to me that with tolerances you might not be gaining much with that change..

[SergntMac]

Any answer I give now is just my guess, I am not that up to snuff on this.

I think the colder stat and plugs work together to bring the motor down to the beginning of the timing adjustment window and provide more headroom for adjustments as the motor quite naturally warms up from floging. I'm relying on the word of the chip's creator, Dennis Reinhart, that colder plugs and stat are just fine tuning for the chip which allow the chip to be more productive. Dennis also said that changing stat and plugs without the chip, is clearly not beneficial, and may come to cause detonation damage over long term use.

I'm getting an air/fuel study later this AM, maybe those numbers will help better explain what's going on. With regards to running just the chip alone, yes, that's fine. But, for the cost of the stat and plugs, why not give the chip it's maximum playing field? Chip alone seems good for 20-25 HP and gobs of TQ, why not go for 30 HP? IMHO.

[MassMarauder]

Sergnt - I guess you would be the one to ask...being from the Big Windy.
I'm from Mass. I'm going to go with the full Reinhart pkg. The stat is the only component that I hestitate to use. I'm concerned that I won't have hot enough heat from my heater. What do you think?

[ONEBADMK8]

You can get a respectable gain from just plugs and stat alone. I prefer the 160 and Autolite 764 plugs gapped at .048.

[RF Overlord]

MassMarauder:

Dennis told me that I might want to skip the t-stat since we actually get winter up here, unlike in FL, etc. Definitely do the plugs, though...

Sergnt...I thought the stock 'stat was a 192° and the Dennis was a 180°?

[SergntMac]

I hear ya Mass, these colder climates have to be respected. I did notice a change on the wait for heat. RF, you're probably right on the 192, it's what I was told, so, the real question is weather (pun intended) or not a 180 degree stat is sufficient for colder climates, and here's another of my informal studies. (I do a lot of this informal s**t)

I'm the kind of driver that doesn't wait on warm up, I start and go. I was used to getting heat by my first land mark, railroad tracks about a mile from the house, about five minutes into the drive with traffic lights and all. On our last "zero" day, I got first heat just before the I-57 on-ramp, about 2.5 miles away, or, 10 minutes into the drive. Perfect timming, I love the on-ramp stuff, and the car should be warm for that.

So, I'd say that the 180 causes a delay in producing heat, not a remarkable reduction in operating temps that the 160 stat OneBad suggests will produce. I can live with this minor delay in zero weather, by the time I'm into serious traffic, I have clear windows and no gloves, so, it seems to me that the 180 could be an all season stat.

RF's advice is sensible too. Why not wait until spring for the upgrade? Stat/plugs aside, when you chip up, and maybe gear up too, negotiating ice and snow is a whole 'nuther program.

Another half a buck of MHO, cha-ching.

[MAD-3R]

If you keep putting your spare change in, you'll be broke. But we are all "enriched" by your contabutions :)

[Heavy351]

I have used everything from 160 to 210 on my carb fed CVPI. Factory thermostat is higher in temp for emissions reasons, downside is lower power.

My stock thermostat was 195- nice and toasty and you would have to turn it down after a while. 205 made the car nearly undrivable (pinging) in any kind of mild weather. I put the 205 in so I could pass the tailpipe test then removed it. Never even attemped 160 in the winter (left deposits on the plugs even in the summer) Settled on 180 for year round use as it was just hot enough to keep the combustion chambers clean.

Now with the computer you don't get that kind of lattitude in tuning and if the motor is too cold you won't get "closed loop" (what is the temp threshold for OBD-II?) operation and your gas mileage and emmisions will totally suck.

8 degrees is nothing, remember the water in your heater core is at least 175 when the fan blows air through it. If you ever find yourself turning down the heat with the stock unit I would be suprised if you even noticed any difference.

[MassMarauder]

Thanks for the feedback. I'll probably try that 180 stat in the spring. When next winter arrives...we'll see what happens. The reality of the matter is that I'm not likely to take the MM out on those frigid days. That's why I kept my Town car.....that and the fact that the dealer didn't want to give me sqaut for it. Worked out good because I didn't want to part with that car anyway. Just LOVE that floaty boaty ride.

[RancorKeeper]

I run a 160 Tstat in my Caprice & I noticed a definite difference in warm-up time my first winter, but after I completely flushed the system, including the heater core, I gained back whatever I might have lost. My heater is now blowing warm air in about 6 minutes. Hot air takes another 2 or 3 minutes. As Heavy351 said, factory Tstats are high for one reason - a hotter combustion chamber burns off more fuel, which is better for emissions. IMO, colder plugs aren't gonna do any good until you really crank up the timing and start experiencing pinging on tip-in. In my experience, they don't do anything for WOT knocks and pings.

[RF Overlord]

Originally posted by MassMarauder
I'll probably try that 180 stat in the spring. When next winter arrives...we'll see what happens.

That sounds like a plan...I don't wanna have to keep changing 'stats every spring and fall...

[schuvwj]

Here is what Fordchip.com says about thermostats:

There are a lot of questions that come up about thermostats. Can you go too cold? What thermostat should I use in my car? Let's put these questions to rest.

A colder thermostat will NOT cause your car to run open loop all the time. The engine goes closed loop based on time, not temperature. A colder 'stat may not make the car run much cooler unless you calibrate the electric fans to turn on sooner. If you have enough air flow (when cruising down the highway) then the engine will run cooler. Around town, in city traffic, it probably won't run much cooler without the fans turning on sooner.

On a supercharged engine, the spark calibration is rarely, if ever, at Maximum Brake Torque spark, or MBT. This is because of higher air temp going into the engine along with higher cylinder pressures. Both of these make the engine more likely to knock. With this type of application, a colder thermostat will allow the engine to run more spark, thus gaining power. It may only be 2-3 degrees, but on a blown engine, that can be as much as 10 ft-lbs.

The hotter the engine runs, the more efficient it is. This assumes that you are not knock constrained like on a blown engine. So, if your engine is naturally aspirated, and it is not knock constrained, then you want to keep the hotter thermostat. If you live in a warm climate, like Texas, then you can probably benefit from a colder thermostat, and thus more spark. The hot air in these type of climates tend to make an engine more likely to knock so a colder 'stat helps in these special situations.

[Donald]

Well, overall seems inconclusive. :-)

I live in the desert. So in the summer the 180 makes sense. But it is now around 45 at night and 65 in the day. So which stat fits that bill?

I think I will go ahead and install the stat and plugs.

[LincMercLover]

Dennis SHOULD have made the chip FOR the 180 (or whichever stat you prefer) stat, which means an adjustment in the fans. If you're really concerned about it, just put a manual fan switch in the car, just don't forget to use it!

[SergntMac]

Everyone has their opinion here, and that is good. I love sharing ideas and experiences here, but, in any reasonsble discussion, the proof of a theory is in the performance numbers...period.

I got my first dyno about two weeks ago, and posted a rather long and confusing thread about the experience. Yesterday, I had another "pro" go over my dyno data and explain to me what these numbers really mean, and confirm some first dyno readings. I'm a tad smarter now (which couild be dangerous) and I am very pleased with the gear/chip/stat/plug upgrade kit from Dennis Reinhart.

RWHP 266.4
RWTQ 285.0
AFR 14.92
Certified top speed with 4:10 120 MPH@6000 RPM
0-60 times 6.03 seconds, in 6/100th mile
Speedo error 40 MPH read is 38.83 MPH

Over the bone stock MM, the upgrade kit is very productive, and well worth the money, IMHO.

[cyled]

I found this that explains about cold plugs and even the gap. The guy is talking about NGK plugs, but it still seems relevant.

Plug Faq (http://www.extrememotorsports.com/plugfaq.htm)

Here is another article from NHRA

Creating the right spark (http://www.nhra.com/dragster/1999/issue25/racing_technology.html)