maestro1024

I have been trying to get my mustang running for a while and yesterday it did run for several minutes.

One issue(amoung others), was the instrument cluster said the heat was way up. But it was not that hot (was not running that long and engine was not hot.

Was going to pick up a new thermostat. Problem is CJ pony parts has a bunch listed. What are the differences between the different ones. Are they all the same with different ranges or do only some of them fit differen cars?

I have 67 289 GT if it matters
http://www.cjponyparts.com/Category....50&sb=&pgnum=1

001mustang

Small block ford needs 195F thermostat.
Engine wear rates increase as engine temp drops below 200F; Continental Motors study.
SBF bad about sludge buildup; hotter oil minimizes sludge.
Water formed from combustion process needs to be driven out by high oil pooling temps; avoid frequent short hops or start ups w/o driving.

OEM gauge accuracy affected by sender range, connection quality, wear.

Buy a cheap IR gun. Check engine, trans, rear end temps.

My data:

Oil stays clean.
Max oil pan temp = 180F (32F ambient)
Head temp=215F (32F ambient)
Intake front driver side=156F (32F ambient)
Intake near tstat= 195F (32F ambient)

2+2GT

I agree. I had it from a Ford engineer who worked on these cars, and he was quite adamant that they were designed for a 190° thermostat. Mileage, performance, reduced sludge buildup, and reduced oxidation of oil were all cited as reasons.

Makes the heater work really well, too.

Jonk67

You can pick them up at most any parts store, STANT #45359 (premium) or #13009 (economy) be sure to get a gasket if they don't come with one. Be sure it's installed with the pointed side towards the rad. and there should be a ~1/8" weep hole around the edge so that water is always squirting through.
Agree with above, go 190*-195* engine will run best.
Jon

maestro1024

I have a friend who recomended a 180(deg) thermostat.

What are the pros and cons of the 180 versus a 190 or 195.

If I put a 180 on their, the engine will stay cooler? That seems like a good thing. Why would I want 190 or 195? Is it related to keeping oil moving at the hotter temp?

I am ignorant. Just want to understand why to pick one versus the other. How big a deal is it?

2+2GT

I have a friend who recomended a 180(deg) thermostat.
Is he smarter than the Ford engineer I knew?

What are the pros and cons of the 180 versus a 190 or 195.
180 will give you less hp, less gas economy, more sludge in the oil.

If I put a 180 on their, the engine will stay cooler?
Sure, if the cooling system is working properly. If your radiator isn't cutting it, though, it doesn't matter what thermostat you use.

That seems like a good thing. Why would I want 190 or 195? Is it related to keeping oil moving at the hotter temp?
Well, I'm a big fan of getting better hp, better mileage, and less crud in the oil. Having a heater that works well is a plus, too.

I am ignorant. Just want to understand why to pick one versus the other. How big a deal is it?
Well, considering the small cost and work to install the one the engine was designed to use, I can't see much point in using the wrong one. Typically, when people have an overheating problem, they try using a cold thermostat. It doesn't work, because, unless the problem was an inoperative 'stat, the cooling system sucks, and a 'stat can't fix that.

maestro1024

Thanks for all the info I picked up the higher rated one.

frdnut

It really depends on what you do with your car and how hot it is where you live...Engines make more hp when they are cooler(within reason)....It is a common dyno trick when looking for big hp numbers..Also some mustangs have a barely adequate cooling system and running a 195 may be too hot for them...I have always ran a 180 or 160 degree thermostat but my cars are only driven in the summer with an eye towards max performance...

001mustang

Max HP is not everyone's goal; more handy on the dyno than MLK Blvd.

NHRA Prostock 1400HP drag car ran super thin oil and 100F engine temps.

NASCAR 800 HP stock car ran thicker oil and 220-240F engine templ.

frdnut

No I never said that it was everyone's goal...It was suggested in the post above that lower temps would give you less hp...I was just pointing out that that isn't necessarily true..