get a catch can for both the valve cover vent and pcv

 

bluish = oil
black =run rich

 

we did a copression test today... 1-2-3 cylinders are reading about 160-150-155 but my cylinder 4 was reading 130 then we drop a little oil and test it again...and it gave us 140! Is 140 bad? how bad?

 

oops

 

^ ???

 

Didnt Dynoflash (AL) have a video or something showing that it is a big no no to run any type of cone filter for a period of time cause the car will be lean.

I remember reading or watching something he did showing that after 30k and no tune with the cone filter the engine blew up or had low compression

Maybe Al can chime in here

 

there are a bunch of things that could have happened, i doubt the "cone filter" had anything to do with this specificly. my guess is the overall lack of a tune and/or bad gas causing detonation which cracked a ring.
no use crying over spilt milk now, time to rebuild.

 

his compression would be lower than that if a ring was cracked

 

^ how low is low?

 

Obviously there might be an issue with cylinder #4. You need to do a leak down test next, I would think.

 

I just did a comp test this morning - mind you this is about 800 ft above sea level in MI. Numbers were 160, 166, 163, 165.

Here is the shop mani info:
Standard value (at engine speed of 250 r/min): 1,128 kPa (163 psi)
Minimum limit (at engine speed of 250 r/min): 951 kPa (138 psi)

8. Measure the compression pressure for all the cylinders, and check that the pressure differences of the cylinders are below the limit.
Limit: 98 kPa (14 psi)

 

Q here - what kind of oil are you using (just checking)?

 

mobil 1 synthetic

 

sounds like a headgasket, but there could be a few things wrong. Unfortunately there is only one way to find out... take off the head and look at everything. You might as well get a new headgasket and some headstuds now. If you take it to a shop, please take it to a good shop not just any "import" shop.

 

there is a 10% tolerance, so you are well out of that range. That is not good.