Thread: Disco 2 engine Mods V8

That is weird , my answer just disappeared!

Anyway I said that it is a waste of time to put in a bigger exhaust valve unless a lot of work is done on the port, as they are TERRIBLE.

I gained a dyno proven 7% with opening out the inlet ports , blending the seats, cutting out the guide from the inlet, and doing a LOT of work on the bowl and roof of the exhaust port. Do not touch the guide as it is a heat sink.
After putting about 48 hours in on the heads, I would recommend having it done profesionally by someone with flow bench.

By the way , my inlet valves were really too small for the seats, and the head place could only do 2 angles on the valve seat. A bigger INLET valve could easily be accommodated by the seat and allow room for a five angle job..
IMHO, unless you need new valves it would be a comparative poor priority to put in new exhaust valves compared with spending that money and more on hand finishing the heads.
Regards Philip A

Originally Posted by Pedro_The_Swift

depends on your definition of simple,,

machine the heads
or
deck the block
or
weld the combustion chamber

the first two are simple machining jobs,,
the 3rd requires skill.


they all require head removal
which is simple,, if your initials are JC

" Thou hast useth my name in vain, prepare for thy punishment; be it by rod or staff???"
- boomed a voice from up yonder, causing the utterer, namely the lowly and unworthy pedro the swift to prostrate himself and offer up appeasements upon the altar of the almighty God Isuzu ...



JC