I was wondering what kind of oil you guys use for your built motors. I'm not interested in debating wether to use conventional or synthetic or what brand. I'm more interested in hearing what weight should be used? I have a built B18B1 with cams, springs, retainers, etc. and a 12:1 compression. I just got the car and changed the oil in it immediately. I chose mobile1 conventional 10w-40. Is this ok or should I be using something heavier or lighter?

 

That is plenty heavy for that motor. I use 10w-30.

 

Amsoil 5w30

 

you bought a car with hi comp and your using conventional?..........

Honda recommends synthetic 5w30 thats what I use.

 

Theres been a thread built a long time ago about this...I suggest finding it.

 

Probably because it was still on break-in.. if not, there's nothing wrong with using conventional. BUT, you should only use conventional on break-in.

Valvoline is probably one of the better conventional oils. We use that for break-in , i know i personally use it on my own motors. From there after break-in i usually switch over to mobil1.

You should be running 10w30 in your b series unless the clearences cause for something different.

 

^^ x2!

 

 

bobistheoilguy.com had tests on most these. redline is a real group 5, unsure on many others. i know mobil 1 became a refined group 3 a few years back.

anyway that site has a lot more oil knowledge than this one

 

Oil weight is totally dependant on your motor. The viscosity (thickness) of your oil, I would assume is determined by compression. Stock B18B1 engines generally run 5w30.

 

So if I was running like 15:1 on a race motor I should run like 20w50 since there's so much compression