Head Gasket Blown on an M54

[Jackcat559]

Well compression & leak down test shows that my head gasket has blown between two cylinders with 20-25 less psi than the other four. I'm putting together a parts list of things needed to replace the gasket. The car is also running 6-8 psi with a VF kit and no plans of going any higher. I was going to order a new head gasket and gasket kit from BMW this week, and already have a Stewart water pump ready to go.

Do I need need studs for the head? If so which ones?

How much should it cost to send the head to the machine shop? Would it just be more cost effective to go for a stage 1 head from http://www.technikpower.com/site/pro...odel_name%3D10 ?

Any other recommendations?

Thanks!

[BMWManiac]

Stick with the stock stuff....plenty strong for 6-8 psi

[UltimateM]

Did the car overheat? The M54 is known to have issues with the head bolt threads pulling out of the block when they overheat. This should be checked before you pull the head by trying to loosen and retorque your head bolts.

[Jackcat559]

Stick with the stock stuff....plenty strong for 6-8 psi

Good to know, thanks

Did the car overheat? The M54 is known to have issues with the head bolt threads pulling out of the block when they overheat. This should be checked before you pull the head by trying to loosen and retorque your head bolts.


Nope never over heated, but I'll check the bolts. The car has 150,000 miles so the gasket doesn't seem too crazy.

[Jackcat559]

How about machine shop costs on average for the head?

[tlmitf]

when you get your head done by a shop - specify what RA you want.
Dont ask me what number you need, i honestly dont know for a BMW head.

[Jackcat559]

"ra" ?

[gerry_miranda]

Ra - Roughness average http://www.schmitt-ind.com/pdf/Roughness.pdf
An expression of measured surface roughness or texture, typically, of a polished or machined metal surface. The arithmetic average value of the departure (peaks and valleys) of a surface profile from the center-line throughout the sampling length, generally expressed in micro-inch (0.000,001-inch) or micro-meter (or micron) (0.0003937-inch) units.

[Jackcat559]

Gotcha, thank you. I guess it's also time to do some research on FI & heads since they will be off any way. Always new stuff to learn.



Would a cometic gasket be any better than OEM? They are in the same ball park price wise.

[mm325]

I would think stock HG with ARP studs would be more than adequate. I'm paying to this thread. attention since I'll soon be an e46er and eventually will use another CF s/c.

[bigugly]

i can get yer head done supa nice.....

decked
valve job
5 angle custom cut
relief cut
radius exhaust cuts
porting
polishing
flow benching

all ranges from 600-3200 depending on how wild you wanna go with it.

[Jackcat559]

unfortunatly a rebuid and something small will have to suffice due to budgetary restraints

[JackEatsEmoKids]

Jackcat, how do you like the 530 with the VF?

If I don't go turbo I was thinking of a VF kit and intercooling it.

[Jackcat559]

It has actually worked out pretty well over the past 3 years. I've never been able to plot a good charge cooler into the system. The piping weather air to water or air to air is a challange. ESS has a charge cooler in their stage 2 system with a twin screw, but that's 8 G's.

You're in the perfect spot for a turbo set up. You have the technical skill and Nick G's shop is up in Pompano, FL. He's one of the best US tuners out there