Was just curious what you guys thik the best way to warm up a cold engine is. When i say cold i mean like 20 degrees out. I am guessing that for a built motor (just like a stock one) it is probably just light load but i have heard otherwise. I have even heard people go so far as to wait until their motor is 100% warm. Just wanna hear some opinions

 

i would let it idle for 1-2 minutes, then drive under 3500 rpm's until your temp is right. at least 5-10 minutes with zero boost. letting it idle for too long isn't the right thing to do.

 

Warm it up on the 2 step at least 6500 rpm's for 2 minutes Maybe?Well if not then try letting alittle heat get in it, like when the temp needle budges from the stop little less than a quarter the more the better, than just dont beat on it till the temp get half way. Jason

 

ok, well another question on this then. I let my car sit for a minute or two, needle comes up a bit. A drive and won't take it past 3k, but the thing never warms up unless i stay sitting in traffic. But then once i start moving again, the temp drops back down to the line. Once i start moving the engine goes cold again, i can't figure it out, you guys got any suggestions.

 

you got me lost there buddy, I have neer heard of acar getting cold when you drive it??

 

yea, it drives me crazy, it might get warm, but once i start getting up in speed maybe 45+ that needle starts to drop back down. This is a built gsr block in a civic coupe with radiator from when it used to be automatic. I know the radiator is thicker, but i didn't think it would keep it running cold.

 

Yea, I just let it idle for about 2-3 minutes. Then drive off slowly til it warms up. keeping the rpms low. My parents leave their car running for 10-12 mins at a time, and I keep on yelling at them for doing that. I guess living in Wisconsin with the winters that we got up there really had them brainwashed. I'm glad it's still in the 60's here in GA.

 

maybe your thermostat is stuck open? sensor is bad?

 

would it really even get up to operating temps and then just drop like that when i start moving again if the thermostat went bad.

 

I just let it idle for atleast 4-5 minutes when its cold or until the needle moves.. summer days I just start it and drive it easy until it comes up to temp.

 

exactly what I was going to say. Your thermostat is stuck open, or you have your HEAT ON TOO HIGH. Happens to me too when it's real cold out. Turn the heat either to #1 until she's warm or off. You will see-- makes a BIG difference on how quick she warms up when it's coooold outside!

 

must be the thermo then, i have the temp all the way on blue, never can touch the heat cause the second i do, the needle drops off.

 

Check and make sure your thermostat was reinstalled.
They could of overlooked it when building the motor.

 

I leave my thermo's out so I can idle and not watch my temps go up and down. I've burnt a few fans that way watching the yo-yo. You just have to let the oil warm up that's all. The reason we have specific temps is so the oil is a little easier to flow. If you run thinner oil you can run lower temperatures(via no thermostat). Once it hits the bottom line your engine i around 100*-110*F and you can drive it normally.
The added wear thing is because the oil is too thick to flow properly. If you switch to thinner oil your temps will climb faster and it'll generally run hotter.
I appolgize for any comments that offend anyone,but I'm amazed how much know how and knowledge from the old-school of Hot-Rodding was lost and isn't pasted down.

 

wow, thanks for the info tzsir. So your saying once the temp gauge is at the line and run the car hard? It's a built block and i don't want to risk hurting anything by racing it when the needle is down there.

 

you are correct in a few things, but what effect does water temp have on combustion? It's a fairly well known fact that prime combustion occurs with 160-170 degree water temps.

 

the reason it cools off when you drive is cause more air is flowing through the radiator and your fan probably isnt kicking on when your still until it gets hot

 

Actually in a turbo charged engine the prime combustion temp. is quite a bit lower do to detonation, and the amount of air in the cylinder. Yes, with N/A engines it is 160*-170*F. This is because of the higher level of fuel atomization that occurs at these temps. If you go higher the mixture becomes too thin and doesn't burn fast enough to really make any power. That's when you start adding more fuel to avoid lean burn conditions. This is why you increase your A/F ratios with forced induction, but if you lower the temps. you can run less fuel. The company I used to work we used to do all kinds of testing with A/F ratio's with gasoline and diesel. We even experimented with Direct injection with gasoline. Very similar to the Misubishi GDI, but without the crappy flowing chambers. The Mitsu chamber's are designed for peak power in lean burn conditions, and fall on their face when you go too far past the 13.8:1 stoich barrier.
Yes my English sucks (not my first language), and yes I come off as a ***** sometimes. I do have a lot of experience with turbo's and efficiency.
Been there, done that.

 

interesting

 

So you leave the thermostat out completely? Do you ever see any ill effects with cyl temps being any higher? I took the thermostat out of mine a while back and the gauge went down but combustion temp went up... Im thinking this was because there was less restriction and the coolant wasnt soaking up enough heat.. it was passing by to quickly to make full use of the cooling system. A slightly cooler thermo did the trick.

 

If you let it set and idle all the time for a long time, i have heard this can wash cylinder walls....anyone have any feedback on the validity of that?

 

Its not going to wash the rings from idling.. unless you are totally untuned barely running with a good sized injector. With correct fuel tunning you wont wash the cyl.

 

I let it idle for a second and then hold the engine at 3000 rpm until the water temp gauge moves and points at the bottom line on the gauge...

 

I let the injectors prime, start it, let it idle for 1-2 minutes, then drive off shirting at 2500rpm and less than 10% throttle, then when the water temp needle has lifted off of the peg and is beginning to move I'll take it as high as 4000 with 30% throttle until it's completely warmed up, then 9700rpm's and 100% throttle it is!

 

Running without a thermastat or it stuck open, "can" create hot spots in the head/block. Becuase the coolant is flowing to fast, upsetting the thermal dynamics of the heat exchange(sp).