254/258 or 248/250 cam for 408
09-27-2007, 06:40 AM
#1
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254/258 or 248/250 cam for 408 I was wondering if I might be able to get some guidance on a cam selection? I have a 408 with 11.1 Cr. GTP Heads Flowed 330@650 Fast90/90, headers
1 3/4-1 7/8 3 1/2 collectors Race weight 3350. I will be spraying a DP 200-300 shot @ times on it and its a T56. I was wondering which cam to go with . I have both cams already but trying to decide on which one to install. Motor is going in this weekend I am leanning on the Cam Motion cam.
Comp Cam 1 254/258 622/622 111L/S no advance
Intake Exhaust
.006 307 311
Valve timing open Close
@.050 Int. 16 58
Exh. 60 18
Lobe lift Int. EXH.
.365 .366
Custom Cam motion has been on a cam doctor correct specs 248.7 / 250.1 628/631 112 + 4 advance
Lobe center intake EXH.
107.8 ATDC 116.5 BTDC
Valve timing open Close
@.050 Int. 17.2 51.5
Exh. 60.9 9.2
Lobe lift Int. EXH.
.396 .371
1 3/4-1 7/8 3 1/2 collectors Race weight 3350. I will be spraying a DP 200-300 shot @ times on it and its a T56. I was wondering which cam to go with . I have both cams already but trying to decide on which one to install. Motor is going in this weekend I am leanning on the Cam Motion cam.
Comp Cam 1 254/258 622/622 111L/S no advance
Intake Exhaust
.006 307 311
Valve timing open Close
@.050 Int. 16 58
Exh. 60 18
Lobe lift Int. EXH.
.365 .366
Custom Cam motion has been on a cam doctor correct specs 248.7 / 250.1 628/631 112 + 4 advance
Lobe center intake EXH.
107.8 ATDC 116.5 BTDC
Valve timing open Close
@.050 Int. 17.2 51.5
Exh. 60.9 9.2
Lobe lift Int. EXH.
.396 .371
Last edited by Street Racer; 09-27-2007 at 07:20 AM.
09-27-2007, 05:34 PM
#2
The 1st cam is way too big for a 408 with 11.0:1 compression. The second cam has a much better IVC for the FAST 90 on a 408 and the exhaust valve opening and close have a better relation to the intake events for nitrous. No question, the second cam is a better choice.
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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
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
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
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX tuning in person or via email press here.
09-29-2007, 11:49 AM
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We Basically Have The Same Set Up I Think If I Remember Correctly My
Cam Is A 245/255 645/655 @ 114 And I Got 568/520. The Only Main Difference Is The Heads I Have Afr 225. My Car Drives Or Better Yet Drove Prety Good, Had A Speed Density Tune
Cam Is A 245/255 645/655 @ 114 And I Got 568/520. The Only Main Difference Is The Heads I Have Afr 225. My Car Drives Or Better Yet Drove Prety Good, Had A Speed Density Tune
09-29-2007, 09:05 PM
#7
Originally Posted by Patrick G
The 1st cam is way too big for a 408 with 11.0:1 compression. The second cam has a much better IVC for the FAST 90 on a 408 and the exhaust valve opening and close have a better relation to the intake events for nitrous. No question, the second cam is a better choice.
I have the big cam but I also have 13.1 compression on my 408 with stage 3 heads (ls6) and fast 90/90. Is that cam ok for my set up? Sorry don't mean to hi jack.
