DCR guys in here!!
DCR guys in here!! I already got my small bore AFR 225's milled 0.018" down to 62cc.However I originally had 11.10cr with the 205s at 66cc and GM MLS gasket.This time around I am going to put a cometic 0.045" with the now new milled heads at 62cc,with quench right at 0.033".SCR would be right about 11.61 now.Does anybody how much the DCR is going up with the current cam I have "TXGIANT" The availabe octane around here is 93.I want to run a smaller cam so I can get better thottle response ANY Ideas??/
You would need to know how much advance is in the cam and what the advertised duration is. I'm assuming your pistons are .012" out of the hole, but what cc are your piston tops?
Advertised duration is the .006" number. Probablly 300+ with that cam. My calculator puts you at 11:87:1 SCR, and my "guesstamate" on your DCR is around 7.8.1. This is assuming your cam has a advertised duration of 301*. Either way, you'd need alot of compression to make that cam work good. Having no advance and being cut on a 114 has made for a very late IVC. You'd need about 13:1:1 SCR to give that cam a decent 8:5:1 DCR.
While you're swapping heads, consider swapping cams. There's lots of more proven choices for making huge area under the curve with 408s at your compression. If you want a recommendation, send me a PM.
__________________
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.
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Verdad Gallardo Ive spoken to Patrik about the cam swap he suggested this:239/248 .649/.615 111LSA (+1) Comp LSK/XE-R lobes
All this now makes sense,I think Im going with it,I hope it feels just as crisp as it feels now
Originally Posted by Patrick G
The IVC of your current cam is 56 degrees ABDC which is WAY too late for a 408. It should be closer to 50 degrees. Your exhaust valve opening is a little too early, robbing you of valuable torque. Overlap at .050" is 21 degrees.
I suggest more lift, less duration, and a narrower LSA.
This will put your DCR at 8.59:1, your IVC at 49.5 degrees ABDC, your EVO is 5 degrees earlier and your overlap is still at 21.5 degrees. This means your every day street manners should be the same or slightly better than your current cam
I suggest more lift, less duration, and a narrower LSA.
This will put your DCR at 8.59:1, your IVC at 49.5 degrees ABDC, your EVO is 5 degrees earlier and your overlap is still at 21.5 degrees. This means your every day street manners should be the same or slightly better than your current cam
Last edited by Patrick G; Jul 6, 2006 at 06:15 PM.
Originally Posted by Beast96Z
Going from 7.8 DCR to 8.6 will be alot more "crisp".
Hey Artic what are ur cam specs?I am about to call comp cams, how will they know the valve events Patrick suggested or do they automatically know with the the figures posted above?I am hoping it will still run like a champ with 93 octane as far as drivability is concerned 
When calling Comp, ask for the following lobes:
#2130 intake
#3734 exhaust
111LSA
1 degree of advance ground in
Also, check with Thunder Racing or TSP before you order. They may charge you less than Comp will. And Thunder will even give you a printout from their Cam Pro Plus so you know the exact specs of the cam you received.
#2130 intake
#3734 exhaust
111LSA
1 degree of advance ground in
Also, check with Thunder Racing or TSP before you order. They may charge you less than Comp will. And Thunder will even give you a printout from their Cam Pro Plus so you know the exact specs of the cam you received.
__________________
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.
Originally Posted by marine02ss
Hey Artic what are ur cam specs?I am about to call comp cams, how will they know the valve events Patrick suggested or do they automatically know with the the figures posted above?I am hoping it will still run like a champ with 93 octane as far as drivability is concerned
