What can go wrong in the Head?

99SE-L · 09-12-2003, 12:40 AM

I'm not hearing anything irratic from the head. The SR20 is always loud. But I've been only able to get 87mph trap speed with a barrage of goodies. I suspect the loss in power comes somewhere from the head because I once over revved and had to replace my cams and a whole bunch of rocker arms and valve shims. That was 20k miles ago. Now i got 30k miles on my car. Can anyone give me some ideas of what might be going wrong and how I would be able to tell? Could I have skipped a tooth? But my low end power seems pretty good still.

These are my mods. AEM CAI, Hotshot Header, Greddy Catback, UR pulleys, 10lb Konig Helium rims, bored and polished maf, polished TB, 18* timing, bypassed TB coolant lines, 80lbs of weight reduction not including from rims. Ghetto Ground Wire Kit. Mobil 1 0w30 synthetic and MT90.

thepep · 09-12-2003, 08:58 AM

Do a compression test and if you are concerned about cam timing, pull the valve cover and make sure the cams/timing chain are in the correct orientation.

Steve

99SE-L · 09-12-2003, 01:06 PM

Quote:

Originally Posted by thepep

Do a compression test and if you are concerned about cam timing, pull the valve cover and make sure the cams/timing chain are in the correct orientation.

Steve

I will go do a compression test later today. I'm about to install a 91intake cam on my car this weekend. I have never opened the valve cover on my car before. How can I tell by looking at it that the cams/timing chain are in the correct orientation and that it did not skip a tooth?

NCSUse-r · 09-12-2003, 01:25 PM

since you are worried about having skiped a tooth it would probably be a good idea for you to remove the whole timing chain cover (PITA) so you can make sure you have everything aligned correctly. Your chain will have marks that correspond to marks on the crank and cam sprockets.

1fastser · 09-12-2003, 01:48 PM

FSM helps too. To truly know you should pull the front cover like NCSUse-r said. With the #1 piston at TDC, there will be a slightly different color link on the chain that corresponds to the mark on the sprocket. The crank will have the notched, half-moon key thingy at 12 o'clock and another mark at 4 o'clock (IIRC). The 4 o'clock position should line up with another slightly different color link on the chain.

Did I miss anything?

laterz...Jody

99SE-L · 09-12-2003, 04:26 PM

Quote:

Originally Posted by 1fastser

FSM helps too. To truly know you should pull the front cover like NCSUse-r said. With the #1 piston at TDC, there will be a slightly different color link on the chain that corresponds to the mark on the sprocket. The crank will have the notched, half-moon key thingy at 12 o'clock and another mark at 4 o'clock (IIRC). The 4 o'clock position should line up with another slightly different color link on the chain.

Did I miss anything?

laterz...Jody

Hey thanks guys.