Which was probably why I replied to someone else’s post, not yours. That person offered something as helpful advice which was unfortunately not a good idea, at least my country’s government and the manufacturer of the main ingredient in the aformentioned additives advise against the use of teflon as a lubricant additive.
somewhat of a highjack here about engine rpms…
my redline (2 liter, 5 sp. manual, Mazda engine) is 7K. So far (in only a couple of months, and this is my first car with a tachometer), I don’t think I’ve pushed it over 4K (at 65 on 5th gear, it runs at 3K). Should I be pushing my revs closer to the redline before shifting? Am I losing efficiency somehow? Long term, am I limiting the engine’s ability to perform at higher revs?
yojimboguy’s questions:
Should I be pushing my revs closer to the redline before shifting?
No.
Am I losing efficiency somehow?
No.
Long term, am I limiting the engine’s ability to perform at higher revs?
No.
Once (if?) hybrid vehicles become common, won’t most engines be subject to instant start-up/shut-down quite often (indeed, at every traffic light, if I read the various proposals right)?
Yes, SirRay, vehicles are being designed as you describe. We need to clarify what most of us assumed from the totality of the opening post, but hasn’t been specifically stated–we’re discussing starting and driving a COLD engine. Warm engine starts are not a concern.
yojimboguy, i mostly shift just before the red line… it won’t do your car any harm to continue driving at 4k rpm, but you won’t get to enjoy the sound of the engine at 7k and for me it’s just not as much fun driving at low revs as it is at high revs… also, your car might have an auto cut-off at the 7k mark wherein it cuts your engine down to 5k or so as soon as you cross the red-line… maybe you could take it to 7k just to see if it incorporates this feature…
[very slight hijack]
i’d like to ask whether turning on the airconditioner when you start a cold engine puts any additional strain on the engine ? and whether i should hold off turning on the ac until my engine warms up ?
[/very slight hijack]
And you wanna know what else it does? The Teflon coats the micron-sized passages in your oil filter. Not good for two reasons: 1) Some passages may clog up, thus reducing flow/increasing back pressure, 2) Passages which are not clogged will be more “slippery,” and thus allow some particles to get through which would not otherwise. I would never put that crap in my engine…
I used Slick 50 in my last car’s engine. This was before I found out it isnt recommended. I’m sure I noticed a difference in acceleration (the engine seemed to rev a bit free-er). But I wouldnt use it again after what I’ve heard.
It gives the engine some more work to do, but it doesn’t stress it in the manner we’ve been discussing in this thread. There’s no need to wait to turn on the A/C. In fact, in many cars the defroster automatically engages the A/C compressor because it helps dehumidify the air.
Now, if the car has been parked in the sun in hot weather and it’s hotter inside than outside, you do want to wait a few minutes before selecting “Max A/C” (most American cars) or “Recirculate” (most Asian cars). Those positions draw air from inside the vehicle. After you’re getting some coldness from the A/C system, this enables getting really cold air. But if it’s drawing in 120 degree air from inside the car instead of 90 degree air from outside, it’s just going to take longer to get cold. Start off with the “Normal A/C” or “Fresh (outside) air” position.
If you have a car that selects between outside air and recirculated air, use the “Recirculate” position only for maximum cooling of the air conditioner. In the “Defrost,” “Vent,” and “Heat” modes, the systems work best with outside air.