i have a b20b that i am going to be putting in my 89 hatch and i was fitting up one of my headers. but when i tried to put them on the header flange hits the block deck in three spots. is this normal on the b20b? here are some pics sorry there crappy shot with cell
hope these make sense

 

Cheap header, just grind the bottom of the flange on the header to clear. With most cheap headers also the bolt holes are enlarged so make sure it's in the right spot and centered on the gasket.

 

they fit fine on my b18
my RMF v1 header was not cheap. and i would like to not grind on that header if i don't have to

 

Grind the header or the block or don't use it. Those are your options.

 

+.500" Thicker head gasket ��

 

Just grind a little on the flange. Put a 45 degree angle where it touches. You won't even be able to see it when it's installed.

 

my order of fixing it

1- thicker gasket
2- grind header flange
3- modify the block.

dont forget to clean all those metal shavings out of the ports.

 

thanks pyroproblem and blackeg.
is this a normal problem on the b20b. my b18a does not have the ridge like the b20.

 

just modify the header. where you need to remove material from the flange won't effect it from sealing. Only an idiot would change the head gasket for that.

 

this was supposed to be a sarcastic response, but the little winky face didn't come out correctly.

 

no way in hell am i going to change the head gasket.
i was just wondering if this is normal for this motor. maybe it's the p8r head thats a little different. i know it is a different casting.

 

Just grind the bottom of the flange of the header like we said, you don't need to take much, just 45 degree the bottom of the flange if it's thick enough. It's a simple fix and it won't affect anything.

 

I know what to do to make it fit.I would like to know if this is common for this motor

 

The problem is not your engine, it is the flange on your header. The issue you are experiencing is common on all "B" series applications because they all have the same areas on them that can, because of casting shift during production, stick out below the bottom edge of the cylinder head. Chinese built headers, as well as uber-cheap Ebay headers typically have larger flanges than well designed headers, and thus, increase the possibility of interference when installed.

Modify the back edge of the header as suggested above for a quick fix. Sending it back to the supplier for a replacement one will almost certainly end with the same problem again.

 

What header is this?

 

plm

 

I ran the same set up a few years back. Shave the header.

 

I also have that problem when I swap from b18 ls long block to the p8r b20 long block. At first I noticed that the header was not seating properly flush/flat on the head when I was tightening the nuts. So I removed all the nuts and see what was causing it to not seat flat and I noticed that the bottom of the header flange was causing it to tilt. So I tried pulling the header up while it's in the studs of the head and it finally seated nice flat. So check that first.

 

thanks for the feed back