Being unfamiliar with these cars. Even after owning mine for 3 years... I had sludge all in my coolant. Car was over heating at freeway speeds. So I assumed head gasket. Pulled the the head, gasket was fine, had the head pressure tester, everything good. After doing some research I found out the problem was the oil cooler....

Fun right? Now that's heads off and already at the machine shop I went ahead and had him do a valve job, I've never seen exhaust valves this small! Ordered arp studs from Full Lock automotive (awesome guys great pricing here highly reccomend them) new head gasket (thicker because I thought my head was warped), new oil filter housing and oil cooler. It's an r50 housing will that work on my 04 MCS? Anyway I'm stock fuel system, 17% pulley, with this valve job how lean with my car be 3 angle exhaust side and 5 angle intake side. Will it be safe to drive? Car has a fresh bottom head, I'm changing S/C oil, timing chain tensioner and a bunch of gaskets. Stock cam right now as well, plan on running the nitrostick ns2 then getting it tuned on ecutec.

 

You said the block is fresh? Oil in your coolant means you have a crack somewhere.

 

Moving this to the Stock Problems/Issues folder.

If the head gasket is good then either you have a crack or depending on the year of the car, and you car looks super clean in that first picture, it could also be the oil heat exchanger. I will see if I can pull the thread on the second issue for you.

 

Here is the thread for the other possibility based on the year.

https://www.northamericanmotoring.co...acks-this.html

 

Here's a link to a recent thread of mine, where the oil cooler ended up being the culprit.

 

Was your radiator support already cracked before you took it apart?

 

Yeah bottom end is fresh, I know that block it good, I ran a block test on the car. Got the head backnyesterday and he took .004 off, and the valve job is beautiful! Car has cp Pistons, mahley rods. Stock compression and dicplacent, had the walls honed when I built the bottom end. Oil cooler showed up today, still waiting on head gasket and S/C oil from Revolution mini works. I just want to stop spending money at this point. Already did water pump, new radiator, metal thermostat housing (I don't run a thermostat, car isn't a daily driver), replaced every single o ring in this this all new gaskets, I've spend a lot of money... my main question I guess is how lean will my car be with this valve job, running a 17% pulley, stock fuel, stock cam? Car is eventually getting new cam, tune etc. and what size/brand injectors are recommended, should I get a new fuel rail?

 

Yes, the radiator support fan shore has been cracked for a while, car is on air ride suspension, aired all the way up still sits pretty low

 

Stop spending money on this issue. I will never stop pouring money into this car. I have a 2jz swapped 96 Nissan 240sx that I love to death but my mini is still my favorite car.