why do i keep blowing headgaskets??!

[dmjensen]

so i just blew a second headgasket tonight. im tired of this, what did i do wrong? (besides turbo e30)

i used a goteze headgasket, meteric blues, and i looked over the head, it seemed true and not warped. i torqued them to 30ftlbs wait 5 min, 40, 50, and then 60.

i have 42lb injectors and @ 1bar of boost, the temp needle was alittle below vertical. i tuned it myself and i had it so that under boost a/f was right around high 12s verry low 13s. i have ngk BPR7ES plugs gaped to .023

its blowing under the intake plenum closest to the firewall in the middle of the last cylinder, is there something i overlooked or is this just going to keep happening?

[bimmerteck]

Did you use a straitedge and a feeler gauge to look for warping or just eyeball it?

[dmjensen]

We used a straight edge ruler, but not a feeler gauge.

[The Humjet]

How many times has this happened to you?
I'd get the head pressure tested and resurfaced. Your not gonna see if your head is warped by eye or with a straight edge ruler. These heads and surfaced to a tight tolerance. I like to make sure everything is within .0005" on each corner when I'm resurfacing heads.
I once had to resurface a head for my parents bmw e46 330i when they blew a head gasket. It pushed up .007" in certain areas, I got it set up on the mill as flat as possible and took a cut. First cut didn't even clean up in some areas you could tell this head was bent like a banana. This was a something I couldn't tell by eye when the head first given to me. Took off .014" for it to eventually clean up so it was completely flat.
If your head is in any shape like my parents cooked e46 then you'll be lifting it in no time.

[dmjensen]

This is the second time. So get it pressure tested and possibley resurfaced

[Zacm829]

I would get it both resurfaced and tested. Better peace of mind.

What management are you running? Any boost spikes? Manual boost controller?

[dmjensen]

Megasquirt pnp from whodwho, no boost spikes, and no mbc its a tial 38mm wastegate with a 1 bar spring

[bimmerteck]

We used a straight edge ruler, but not a feeler gauge.

Not a ruler, a machinist's straight edge. It's a tool used with feeler guages to check if surfaces are in fact, straight.

Straight edge from summit racing

[dmjensen]

yup, my dad is bringing one home from school. (shop teacher)

i'll check it and if it is not the head what else would cause this? or is this almost 99.9% the head?

[bernzpeed]

so u might not be operating in the right temperature, have you checked the radiator, coolant and was it bled completely?

[nando]

how about o-ringing the block?

how have you tuned your timing map? could it be knocking?

what about ARP studs instead of metric blues?

[dmjensen]

temp is at the same as it always has so i believe it would be correct, id check but its hydro locked untill i get a chance today

im thinking the PO had the engine oringed because of the condition of the pistons/cylinder walls are flawless

arp's arent an option at the moment due to money shortages

[nando]

o-ringing has nothing to do with the pistons or cylinder walls. you would notice it - it's usually a stainless steel wire that goes in a groove cut around the tops of all the cylinders, sticking up about .5mm, that bites into the gasket to prevent it from shifting around.

[bimmerteck]

The first min. of this video shows how to use a feeler gauge to check for a warped cylinder head using a straight edge and a feeler gauge.

http://www.youtube.com/watch?v=cwn8Epoezog

[Jaxx_]

I feel like you are a little lean if you're at 15psi and 13s. I'd like to be low 12s to mid 12s under boost.