Does any head produce better economy?
#1
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Presumably this would show up in lower bsfc, however part throttle is more important than WOT here. This is for a CI 6L, rated at 300hp. More hp isn't needed, per se, although a few more would help. Wouldn't want to reduce power though.
In a 2000 Yukon 2500...just wondering if newer designs could improve economy enough to justify the cost (at 20¢ per mile for fuel, it wouldn't take that much of an improvement).
In a 2000 Yukon 2500...just wondering if newer designs could improve economy enough to justify the cost (at 20¢ per mile for fuel, it wouldn't take that much of an improvement).
#2
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You would lose power but go with a head that will lower your compression (i.e. larger chamber) and that could improve economy. I highly doubt you will find many ways to increase performance or keep it the same and get good fuel economy. If that were the case, they would've made them like that.
#3
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When CARB was certifying the AFR 205 heads, they found that they not only were cleaner than stock LS1 or LS6 heads, they also returned 2mpg more than stock. For these reasons and many others, the AFR 205s received the CARB certification for being emissions legal. That's like having your cake and eating it too.
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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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
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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
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.
#4
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I was thinking the AFRs and TFs (and maybe the Darts) would have more efficient combustion and maybe better swirl. However, they all seem rather large at the 300hp level. With the right cams, they are over 500 crank hp.
The CARB test was a complete emissions street cycle, correct?
The CARB test was a complete emissions street cycle, correct?
#5
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I went with the Dart 205's and also picked up some mileage, I am getting 34.5 in sixth gear now. I think the higher compression had a lot to do with it but am not sure. I do know my mileage average as well as cruising has improved so a set of heads can help from what I have observed with my car.
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Originally Posted by DavidNJ
Presumably this would show up in lower bsfc, however part throttle is more important than WOT here. This is for a CI 6L, rated at 300hp. More hp isn't needed, per se, although a few more would help. Wouldn't want to reduce power though.
In a 2000 Yukon 2500...just wondering if newer designs could improve economy enough to justify the cost (at 20¢ per mile for fuel, it wouldn't take that much of an improvement).
In a 2000 Yukon 2500...just wondering if newer designs could improve economy enough to justify the cost (at 20¢ per mile for fuel, it wouldn't take that much of an improvement).
212 Cam ,AFR 205's -gained 80hp/65tq and the owner gained an average of 3-4mpg. Can't beat that
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a small runner size like the dart/afr 205's help..Setting your quench nice and tight in the .035 to .045 range helps..And increasing your compression also helps..These three things will increase combustion efficiency which is what you are looking for with increased gas mileage...People get into trouble here when they chose a camshaft..Plain and simple the more overlap you have,the more gas mileage you will lose..With my setup that i have tuned with hp tuners..I got my gas mileage back to stock,but it wasnt easy and took lots of work..
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#8
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Originally Posted by SVT THIS
You would lose power but go with a head that will lower your compression (i.e. larger chamber) and that could improve economy.
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#10
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Originally Posted by Slowhawk
We just did a 06 V-max 6.0 truck.
212 Cam ,AFR 205's -gained 80hp/65tq and the owner gained an average of 3-4mpg. Can't beat that![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
212 Cam ,AFR 205's -gained 80hp/65tq and the owner gained an average of 3-4mpg. Can't beat that
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
Headers and/or exhaust also in the swap? Did you use the newer Comp XFI Extreme Truck grind (212/216, .520/.524, 115 LSA), or one of the more aggressive XFI RPM HI LIFT cams (212/218, .558/.563, 115 LSA)?
Thanks in advance!
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Originally Posted by SVT THIS
You would lose power but go with a head that will lower your compression (i.e. larger chamber) and that could improve economy. I highly doubt you will find many ways to increase performance or keep it the same and get good fuel economy. If that were the case, they would've made them like that.