Engine to frame alignment

[rcotner]

I noticed something strange when installing my exhaust. The flange connecting the headers to the first section of exhaust is oriented at a different location relative to the frame on the drivers side compared to the passenger side by about an inch. Inspection of the engine shows about the same difference from the passenger side valve cover to the firewall compared to the drivers side valve cover to the firewall. The transmission is relatively well centered in the frame. Is it possible that there is that much error in how square the frame is to the engine mounts? As is I will have to shorten the passenger side exhaust about an inch to match the drivers side. That does not seem right... Weird! Any help out there?

[Silent T]

The heads on all V8's are not "squared" in relation to the block - more like a parallelogram.. The number one cylinder is slightly ahead of the number 2 so therefore that head is slightly forward of the other - some more pronounced than others. One head will be closer to the firewall.
As long as your engine centerline is set - which sounds like it is from the trans observation - you should by just fine.
Exhaust manifolds are usually different from side to side as well...

[michael everson]

Usually the offset is the same thickness as the connecting rod. The left and right banks cannot share the same spot on the crankshaft. Hence the offset.
Mike

[erlihemi]

I would have thought that if your building a "standard kit" FFR would have made up the difference in the first pipe off the flange. As mentioned above the heads are offset so maybe FFR intended a particular manifold combo. Easier to shorten than stretch!!

[rcotner]

Thanks for all of the feedback. I learn something new every day. The headers are asymmetrical relative to the bell housing, obviously because of the cylinder offset.