Compression Calculators
But just in case, here is a link to a good SCR/DCR calc from the advanced tech section.
https://ls1tech.com/forums/advanced-...readsheet.html
Assumptions:
1. 0 piston to deck height, supply piston compression height for a more accurate calculation
2. Head gasket is a Cometic .040/3.910
I need advertised cam duration numbers to calculate DCR
. I wouldn't worry about DCR
, it doesn't mean anything.
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Any more advance and it detonates. If I run race fuel mix, I can go another 2* with no issues.
So I guess you guys do not believe detonnation exists either.
The thing is it is not the same for all motors (depending on chamber design, quench etc...) so I do agree that there is no real rule of thumb, but there are limits which you do not want to cross.
One important aspect of running high compression and controling detonnation are cam specs, and the valve event to watch is IVC.
Late IVC will fight of knock better than early IVC cams. The ratio of the cylinder volume at IVC over the volume above the piston at TDC represents the dynamic compression ratio. That is the corrolation of DCR/octane and detonnation.
That is why I designed my cam with 49 IVC and that I have little issue even in hot weather.
224/222 making 463rwhp of neck snapping throttle response (370cid)
So yes DCR matters.



