807-13

[BERNIEHUMBER]

HI:Here is a shot of a 807-13. I know some go in with out a modified mount where others need a plate.Which do I have?The car is 2 hrs away so I wanted to go prepared.
Thanks

[jbcollier]

I think that should go straight in.

[jbcollier]

Yup, you're good.

http://www.syer.net/comparativepics.htm

[BERNIEHUMBER]

HI:Thanks.I was looking at that shot of the 821-04 block and every second time I looked I found a problem,you know watch something long enough and you start to doubt yourself!!!
I had a bit of a problem finding the 42 mm intake valves(FI engine) but I would rather deal with a 42 mm than some of the 807-13's with the 40mm.I had to do a bit of porting to make the twin 40 Webers feel at home on the head but this isn't a overnight project.
Thanks again
Bernie

[jbcollier]

Easy on the porting.  You want a nice gentle taper from the carbs through to the valve.  Especially do not lower the "floor" of the port.  This is a common mistake as it "visually" improves access to the valve.  It actually directs flow across the valve which significantly lowers the air flow.  Sorry, just a hobby horse of mine.

[BERNIEHUMBER]

HI:Used a flow bench (inclined manometer in thermo lab where I teach) to do a before and after.Easy to remove, hard to replace.If you mess with the actual seat dimensions, way more harm done than positive effect.
Take care