Patrick G or PREDATOR-Z = DCR help!!!
Patrick G or PREDATOR-Z = DCR help!!! You all are the go to guys for this...
I'm having a heck of a time calculating my DCR. I found & used the excel spread sheet based on Comp grind cams.
Here is what I have for my setup:
Heads are 241's milled down to ~58cc (~11.5 CR)
Stock GM MLS gaskets
Cam is F13 (230/232 .595/.585 114*)
Punched in the #'s I knew into the spread sheet & got an error on the DCR tab (orange) but got it to work on the DCR Manual Calc (Blue Tab). I calculated out the following:
Static Compression Ratio 11.58
Dynamic Compression Ratio 9.00
Static looks right but got a DCR of 9.?.?.? That has to be not good b/c I thought mid to upper 8's we about the max for 93 octane pump gas.
If I did it correctly & my DCR is 9 I am worried it will be too high.
If so how do I fix it? Thicker gasket? Could I remove some of the material in red to increase the CC size? Would that mess up the swirl & flow of the heads? HELP
I'm having a heck of a time calculating my DCR. I found & used the excel spread sheet based on Comp grind cams.
Here is what I have for my setup:
Heads are 241's milled down to ~58cc (~11.5 CR)
Stock GM MLS gaskets
Cam is F13 (230/232 .595/.585 114*)
Punched in the #'s I knew into the spread sheet & got an error on the DCR tab (orange) but got it to work on the DCR Manual Calc (Blue Tab). I calculated out the following:
Static Compression Ratio 11.58
Dynamic Compression Ratio 9.00
Static looks right but got a DCR of 9.?.?.? That has to be not good b/c I thought mid to upper 8's we about the max for 93 octane pump gas.
If I did it correctly & my DCR is 9 I am worried it will be too high.
If so how do I fix it? Thicker gasket? Could I remove some of the material in red to increase the CC size? Would that mess up the swirl & flow of the heads? HELP
Last edited by cdoggy81; Oct 14, 2008 at 08:02 PM.
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
I would need the .006 advertised durations of that cam.
If you are indeed over 9.0 DCR, you can retard the cam a bit like 2* or 4* to lower DCR.
Also you can un TR6 plugs (colder than stock) to help with detonnation and through tuning (reduced timing)
If you are indeed over 9.0 DCR, you can retard the cam a bit like 2* or 4* to lower DCR.
Also you can un TR6 plugs (colder than stock) to help with detonnation and through tuning (reduced timing)
That is a Futral cam. They use Cam Motion to grind their cams. XER is Comp Cams.
F13
.050" 230\232
.200" 151\150
.006" 280\284
Assuming -.007 deck height, .0053 compressed head gasket and 114+4 (a guess) I came up with 11.58 and 8.81.
Last edited by DrkPhx; Mar 16, 2008 at 08:38 AM.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
DrkPhx, THANKS for the #'s!!! 
OK, so it is looking like 8.6 to 8.8 DCR. Is this too high?
No chamber work done, just milling the heads. If I need to do something what can be done? Can I open them up in the red area in the pic? Will that effect the flow?
Thanks for all the help guys
OK, so it is looking like 8.6 to 8.8 DCR. Is this too high?
No chamber work done, just milling the heads. If I need to do something what can be done? Can I open them up in the red area in the pic? Will that effect the flow?
Thanks for all the help guys
You all are the go to guys for this...
I'm having a heck of a time calculating my DCR. I found & used the excel spread sheet based on Comp grind cams.
Here is what I have for my setup:
Heads are 241's milled down to ~58cc (~11.5 CR)
Stock GM MLS gaskets
Cam is F13 (230/232 .595/.585 114*)
Punched in the #'s I knew into the spread sheet & got an error on the DCR tab (orange) but got it to work on the DCR Manual Calc (Blue Tab). I calculated out the following:
Static Compression Ratio 11.58
Dynamic Compression Ratio 9.00
Static looks right but got a DCR of 9.?.?.? That has to be not good b/c I thought mid to upper 8's we about the max for 93 octane pump gas.
If I did it correctly & my DCR is 9 I am worried it will be too high.
If so how do I fix it? Thicker gasket? Could I remove some of the material in red to increase the CC size? Would that mess up the swirl & flow of the heads? HELP
I'm having a heck of a time calculating my DCR. I found & used the excel spread sheet based on Comp grind cams.
Here is what I have for my setup:
Heads are 241's milled down to ~58cc (~11.5 CR)
Stock GM MLS gaskets
Cam is F13 (230/232 .595/.585 114*)
Punched in the #'s I knew into the spread sheet & got an error on the DCR tab (orange) but got it to work on the DCR Manual Calc (Blue Tab). I calculated out the following:
Static Compression Ratio 11.58
Dynamic Compression Ratio 9.00
Static looks right but got a DCR of 9.?.?.? That has to be not good b/c I thought mid to upper 8's we about the max for 93 octane pump gas.
If I did it correctly & my DCR is 9 I am worried it will be too high.
If so how do I fix it? Thicker gasket? Could I remove some of the material in red to increase the CC size? Would that mess up the swirl & flow of the heads? HELP
had an 01 motor that was -.008
the 98 motor i have now is right at the same, that's why I was using that deck height, i believe the older the graphite gaskets were .053, the new GM MLS i read are suppose to be .060, but cant confirm that measurement
the 98 motor i have now is right at the same, that's why I was using that deck height, i believe the older the graphite gaskets were .053, the new GM MLS i read are suppose to be .060, but cant confirm that measurement
