To people with worked G180's or G200's

[Josh]

Ok here a decent question... Anyone with a worked G series engine must have come accross this problem and I have NEVER seen it covered in this forum. Here goes; How have you guys gone about making up for machining thats gets done on a worked G series engine. By that I meen decking the block and machineing the cylender head you are moving the timing sprockets closer therefore retarding you cam timing (depending on how much you block and head have been machined) Someone MUST know about this and have a decent solution...

Hope someone can help me out

Josh

[Pervert]

Thicker head gasket?? dunno mate, but i neva really did think about that. Good question i'd like to see the replys to this one.
cheers

[Ben Wight]

The same thing happens in any OHC engine where the cam is driven from the crank.

The budget way to increase compression is to machine the head or block, but as you pointed out, this disturbs your cam timing. You need to adjust the cam timing back to manufacturers specs, or to the specs that make it most efficient.

this can be done a few ways, the easiest being to jump a tooth on the cam gear, each tooth is 10 degrees, so its a pretty coarse adjustment.

The best way is to get an vernier timing set, which allows an adjustment of 4 degrees viam a multi keyed sprocket gear. Crow make one, and its about $110.

www.crow.com.au

Ben

[Greg]

Hmm, I hadn't thought of that too much before either. I guess that might be why the powerband of my motor changed after the rebuild (G180). In stock form she'd rev a real lot, but now she makes peak at about 4800rpm and doesn't want to go over 5000. Real torquey down low though. I might invest in one of those vaneir timing gears before I get it dyno'd then...

Greg

[Josh]

thats excatly what happens, I know the stroke of a G180 is longer making more toque but it's also the other factors that come into place when people say these engines dont wanna "rev up". Oh course the guys running turbos know this already