cold start up
 

hi i've just finished building my ej20 with forged internals etc etc. however i am now worried about cold starts. the car is going to be my daily driver just wanted to know if im too keep on with the, warming of the ar before drivering off to work in the mornings??

Always warm up mate, try not to use boost until warm then take it easy for a few miles to warm diff,gearbox.

never leave a car to warm up on the drive. you do more harm that good. always drive striaght off. of course dont go mental for a couple of miles.

really?? i thought that you were to let it warm up before moving? so this is wrong, driving the car off boost until warm is the way to go?

"never leave a car to warm up on the drive. you do more harm that good. always drive striaght off"

dj219957 can you explain the above ?

I always thought it was a bad idea not driving straight off and letting any engine just warm up on the drive, something to do with the oil churning over in the sump and apparantly this isnt good for it in some way, also i would of thought that the top end would be receiving less oil than the bottom due to no revs and no oil getting thrown up top?

When you start the car the engine revs sit at about 12 - 1300, then as the engine warms the choke will come off. imho driving straight off would cause more wear as the pistons have not expanded through warming and piston slap is still evident more so in a forged engine.

Not allowing the pistons to expand at low revs would cause the pistons to rattle as they travel, bearing in mind you would be poss revving to 3000rpm without boost. Your oil is being circulated with no probs otherwise you could not sit in traffic for extended periods of time.

no, the idea is to get the engine upto temp as soon as possible. most engine wear occurs during the cold phase and the sooner you get out of that the better. all the talk of pistons makes no sense.

"Not allowing the pistons to expand at low revs would cause the pistons to rattle as they travel, bearing in mind you would be poss revving to 3000rpm without boost. Your oil is being circulated with no probs otherwise you could not sit in traffic for extended periods of time. "

but they are still gonna slap if you leave it on the drive! and for longer if left on the drive to warm. the pistons will expand very quickly if you drive off.

you want to get that oil upto temp quick so it can work at its best. as said work the engine but dont go out on full chat.

agree with dj

Agree, get moving but gently, plus sitting there on idle has more chance of sooty values, bores, leading to pink/knock. More important is, never rev/drive hard from cold and dont rev when about to turn off, plus lots of nice oil changes of course/general maint to keep her running sweet and enjoy. My forged items knock sometimes just for few seconds at start, with puff of blue out the exhaust and engine is new...that's the norm, I dont idle her for ages, just drive off with light throttle.

Its easy, get in car, start car, put seatbelt on, check mirror(s) do your reverse/forward/indicate bit and off you go :D thats as long as you need to leave your car before you drive off ;)

Tony:)

ok so why on earth when i purchased the car the subaru garage (leicester) that i got it serviced at told me to run the car till warm before moving and wait till the fan came on before turning off!

couldn't be arsed with that so i got a turbo timer. but i hate the bloody thing and thinking about not rewiring when the car is complete.

you think they know what they are talking about?

Most of the dealerships ive had dealings with (subaru and others) dont know sh*t about the cars they sell. Take it to a good specialist and take advice from them.

I wouldnt listen to dealers, especially the salesmen. They know didly squat.