Updated Valve event / DCR / SCR / Header length spreadsheet
Originally Posted by matts22
Great stuff guys...
I did notice a problem though. When you go under the tab "Compare DCR" there is no formula in cells B42 and G42, clearance volume. This should be the same as in B42 of the "DCR" tab, which is =SUM(0.7853982*(B17^2)*B21) (and for the G column, just substitute G for B in that formula.
If this isn't fixed, it will throw off the SCR and DCR values in this tab.
I did notice a problem though. When you go under the tab "Compare DCR" there is no formula in cells B42 and G42, clearance volume. This should be the same as in B42 of the "DCR" tab, which is =SUM(0.7853982*(B17^2)*B21) (and for the G column, just substitute G for B in that formula.
If this isn't fixed, it will throw off the SCR and DCR values in this tab.
Also found that ICA uses column B as well. Should be G
What are we looking for when comparing cams using the same heads. I know we want a DCR close to 8.5, but what else?
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Joined: Oct 2005
Posts: 430
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Hi J-Rod.
This did everything I wanted some months back, so maybe I'm just looking for something different now. All I want is to look at various DCRs vs. SCR and IVC. All that the speadsheet should need is stroke, rod length, SCR and IVC @ 0.006", 0.050" or 0.200" to do this. How do I skip over the other couple of dozen specs? For example, do I have to 'invent' an intake cam duration and ICL to get the desired IVC to appear in the box, or...? Ditto how/where can I enter the SCR I want to use without having to create it from a handfull of volumes plus the engine bore & stroke?
Thanks.
-MB
This did everything I wanted some months back, so maybe I'm just looking for something different now. All I want is to look at various DCRs vs. SCR and IVC. All that the speadsheet should need is stroke, rod length, SCR and IVC @ 0.006", 0.050" or 0.200" to do this. How do I skip over the other couple of dozen specs? For example, do I have to 'invent' an intake cam duration and ICL to get the desired IVC to appear in the box, or...? Ditto how/where can I enter the SCR I want to use without having to create it from a handfull of volumes plus the engine bore & stroke?
Thanks.
-MB
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Originally Posted by The stunningman
Ditto I can't get it to open It sends me to another D/L board(?) where I can't figure out what to do. 
Is the server down? I tried to right click and save and I get an error about the server being down or unrecognized.
I'm trying to calculate my dcr and scr change from going from a stock 0.056" gasket to a 0.040" gasket.
Thanks.
I'm trying to calculate my dcr and scr change from going from a stock 0.056" gasket to a 0.040" gasket.
Thanks.
i have been noticing theres a problem with the calculation of scr, and if you look under head gasket volume thats where the problem is its way lower than it should be, so i clicked on it and it says inconsistent formula.
TECH Fanatic
Joined: Mar 2003
Posts: 1,946
Likes: 1
Let me make sure I using this spreadsheet correctly:
If my pistons are .007 above the deck of the block (sticking out) I enter that as -.007 in the spreadsheet, Right??? Not as a positive value, because you are calculating how much of the gasket/chamber volume the piston is taking up...???
For example: ( the below would should pistons sticking-out of the block by .007)
Bore______________________________________4
ST = Stroke_______________________________3.622
RL = Rod Length____________________________6.098
Number of cylinders_________________________8
Deck Height_______________________________-0.007
Piston Dome or Dish (- for a dome + for a dish)__0
Compressed Head gasket thickness____________0.06
Cylinder Head Chamber Volume________________64
???
If my pistons are .007 above the deck of the block (sticking out) I enter that as -.007 in the spreadsheet, Right??? Not as a positive value, because you are calculating how much of the gasket/chamber volume the piston is taking up...???
For example: ( the below would should pistons sticking-out of the block by .007)
Bore______________________________________4
ST = Stroke_______________________________3.622
RL = Rod Length____________________________6.098
Number of cylinders_________________________8
Deck Height_______________________________-0.007
Piston Dome or Dish (- for a dome + for a dish)__0
Compressed Head gasket thickness____________0.06
Cylinder Head Chamber Volume________________64
???
Last edited by SideStep; May 1, 2007 at 12:31 PM.
12 Second Club
Joined: Mar 2006
Posts: 302
Likes: 1
From: Sarasota, FL
Is there any reason the sheet does not consider top ring volume? Or is that hidden somewhere I haven't seen it?
Adding it to my version of the sheet, I get a stock SCR for an LS-1 of 10.13 as opposed to 10.31 without it. That's assuming a top ring down distance of 0.250", which seemed a reasonable number. I don't have the actual stock dimension, does anyone?
Adding it to my version of the sheet, I get a stock SCR for an LS-1 of 10.13 as opposed to 10.31 without it. That's assuming a top ring down distance of 0.250", which seemed a reasonable number. I don't have the actual stock dimension, does anyone?
I take it was omitted as to error in the direction of safety. I would think over time a little carbon is going to build up somewhere in the chamber increasing compression ever so slightly. So having a little cushion is fine with me.
This spreadsheet gives out fairly high dynamic compression numbers... A stock LS1 with the 230+ degree duration cam gives me very close to 8.5:1 dynamic. Correct me if I am wrong but that is a said "limit" for pump gas, which would not make sense with a cam that big on a stock SCR LS1.
Originally Posted by SySt666
This spreadsheet gives out fairly high dynamic compression numbers... A stock LS1 with the 230+ degree duration cam gives me very close to 8.5:1 dynamic. Correct me if I am wrong but that is a said "limit" for pump gas, which would not make sense with a cam that big on a stock SCR LS1.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.