Help with DCR
07-17-2017, 01:54 PM
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Help with DCR I am pulling my cam only ls1 for a freshen up. I currently have a stock '02 LS1 with polluter v2 cam, tsp 1 7/8" longtubes, MWC 9" with 3.73 gears and freshly built a4 with 3600 edge racing converter built for n20. The car is stripped down and lightened up with supporting suspension modifications.
As for my question. I plan on installing new H beam rods(9.125), forged pistons (3.905)reusing the stock crank/ block and tsp 62cc 225 as cast heads. Also of course new bearings and gaskets with the stock ls6 intake and larger injectors. This motor will see 200-250 shot on a regular basis because it is a track only car. I would like to keep the polluter v2 cam but if it will raise the dcr so high that I can't run 93 octane I will swap it. I will be using a stand alone with race fuel for the wet nitrous shot. But would like to keep the engine on 93 octane.
With 2cc flat top pistons I show a SCR of 10.75 to 1. The DCR came up to 9.53 to 1. I may be doing something wrong so any help is appreciated. I used 47.6 inlet valve ABDC as per the cam card.
As for my question. I plan on installing new H beam rods(9.125), forged pistons (3.905)reusing the stock crank/ block and tsp 62cc 225 as cast heads. Also of course new bearings and gaskets with the stock ls6 intake and larger injectors. This motor will see 200-250 shot on a regular basis because it is a track only car. I would like to keep the polluter v2 cam but if it will raise the dcr so high that I can't run 93 octane I will swap it. I will be using a stand alone with race fuel for the wet nitrous shot. But would like to keep the engine on 93 octane.
With 2cc flat top pistons I show a SCR of 10.75 to 1. The DCR came up to 9.53 to 1. I may be doing something wrong so any help is appreciated. I used 47.6 inlet valve ABDC as per the cam card.
07-17-2017, 03:22 PM
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Use the 0.006 lift intake valve close event to calculate DCR. Not the 050 lift event
07-17-2017, 04:48 PM
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Thanks, that is what I was thinking and I didn't want to leave power on the table by not figuring it correctly and setting it up with lower compression pistons. I still have no idea how to calculate advertised duration because Tick uses cam motion cores and not Comp so the cam card does not include an advertised .006 duration.
07-17-2017, 05:44 PM
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