Compression/Octane

[Randy Grein]

It's a standard fix and works well. You have to re-index the cams  
though - easy to screw it up. If you're not really comfortable  
pressing the sprockets off have someone do it for you - best is to get  
adjustable sprockets.
Randy Grein, WMRRA #41

On May 13, 2008, at 8:31 AM, Steve Robertson wrote:

> Yes. They are flat tops with no dish at all and minimal valve  
> pockets. I used
> some modelling clay to check the PTV and even with some very  
> aggressive
> cams there was 100thou on the intakes and 60thou on the exhaust  
> valves. I
> don't know where a stock motor would measure, but these pistons were  
> down
> in the cylinder 60thou at TDC.
>
> I wish I knew more how cams work. I'm tempted to remove the exhaust  
> cams
> and replace them with some Gen1 intakes. This would give me about  
> 20thou
> more PTV on the exhaust valves and from what I understand a little  
> bit better
> low end torque while perhaps giving up some top end. Make sense?
>
>
>> so you are running aftermarket pistons?  I am running 100 octane  
>> with no signs of detonation.
>