Carb opinions 540's 700 hp...
03-19-2015, 08:39 AM
#31
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How about dynoing with your 800, and again with a dominator. Takes 5 minutes to swap carbs. See if its worth it to you or not. I'm sure someone has a carb u can borrow for the dyno
I look at it this way. You built new 540s to replace the old 548's that made 600hp. You spent a lot on new cylinder heads, paid extra for the CNC chamber porting, a custom cam for the engine , all in an effort to improve airflow. Why stop at the carb? If the heads (just throwing numbers out there ) are worth 25hp over the old heads, and the custom cams worth 25 HP over the old cams, what if your carbs are gonna cost you to lose 25hp? When you add it all up the carb upgrade would have been the cheapest power upgrade out of the package. Now if its 10hp then maybe not worth it.
On a 6000rpm 540 with AFR heads and a custom cam, making say around 700hp, you just may see a nice jump in power by bolting on a dominator. 600hp 540, prob not. Have guys made great power with 4150s, of course. Only way to know is to test. If your on the dyno and get your carb tuned at say 12.5 Afr at 6000, and swap it out for a dominator, you'll have to tune the dominator for a 12.5 Afr at 6000 as well for a direct comparison. I've seen where guys did this test, had the 4150 tuned perfect, then slapped a dusty old dominator on with a pig rich setup, see no gains or even losses, and say the dominator sucked. Not a fair comparison.
I look at it this way. You built new 540s to replace the old 548's that made 600hp. You spent a lot on new cylinder heads, paid extra for the CNC chamber porting, a custom cam for the engine , all in an effort to improve airflow. Why stop at the carb? If the heads (just throwing numbers out there ) are worth 25hp over the old heads, and the custom cams worth 25 HP over the old cams, what if your carbs are gonna cost you to lose 25hp? When you add it all up the carb upgrade would have been the cheapest power upgrade out of the package. Now if its 10hp then maybe not worth it.
On a 6000rpm 540 with AFR heads and a custom cam, making say around 700hp, you just may see a nice jump in power by bolting on a dominator. 600hp 540, prob not. Have guys made great power with 4150s, of course. Only way to know is to test. If your on the dyno and get your carb tuned at say 12.5 Afr at 6000, and swap it out for a dominator, you'll have to tune the dominator for a 12.5 Afr at 6000 as well for a direct comparison. I've seen where guys did this test, had the 4150 tuned perfect, then slapped a dusty old dominator on with a pig rich setup, see no gains or even losses, and say the dominator sucked. Not a fair comparison.
Last edited by MILD THUNDER; 03-19-2015 at 09:04 AM.
03-19-2015, 08:48 AM
#32
I know Dale is a go to guy for cars not sure about boats, none of my past engines needed crazy tuning or a big carb, my 600's ran sweet with hp500 carbs with doing wot runs **** off then pull plugs... But in this case I wanna make sure I don't starve engines for air or fuel, I can run my 800's to get by if needed I built engines around using dominator or equivalent ... I don't wanna spend lots of money and be close to max, rather have room for later ...
Guys say 900 is enough, others say 1050+ very respected people told me Dominators.... It's not really the carb being issue I wanna know if I am keeping my intakes or not...
Guys say 900 is enough, others say 1050+ very respected people told me Dominators.... It's not really the carb being issue I wanna know if I am keeping my intakes or not...
You'll learn more about carburetors in 1/2 hours than you can imagine.
03-19-2015, 08:57 AM
#33
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The Quick fuels are really nice units, still confused how they had perfect AFR`s on the dyno for a 1200hp motor and a 1000hp motor out of the box with no changes.
Tim, I`d say you`d be perfectly fine with a QF 1050
Thy`re real preeeeety too
03-19-2015, 09:01 AM
#35
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03-19-2015, 09:08 AM
#37
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How about dynoing with your 800, and again with a dominator. Takes 5 minutes to swap carbs. See if its worth it to you or not. I'm sure someone has a carb u can borrow for the dyno
I look at it this way. You built new 540s to replace the old 548's that made 600hp. You spent a lot on new cylinder heads, paid extra for the CNC chamber porting, a custom cam for the engine , all in an effort to improve airflow. Why stop at the carb? If the heads (just throwing numbers out there ) are worth 25hp over the old heads, and the custom cams worth 25 HP over the old cams, what if your carbs are gonna cost you to lose 25hp? When you add it all up the carb upgrade would have been the cheapest power upgrade out of the package. Now if its 10hp then maybe not worth it.
On a 6000rpm 540 with AFR heads and a custom cam, making say around 700hp, you just may see a nice jump in power by bolting on a dominator. 600hp 540, prob not. Have guys made great power with 4150s, of course. Only way to know is to test. If your on the dyno and get your carb tuned at say 12.5 Afr at 6000, and swap it out for a dominator, you'll have to tune the dominator for a 12.5 Afr at 6000 as well for a direct comparison. I've seen where guys did this test, had the 4150 tuned perfect, then slapped a dusty old dominator on with a pig rich setup, see no gains or even losses, and say the dominator sucked. Not a fair comparison.
I look at it this way. You built new 540s to replace the old 548's that made 600hp. You spent a lot on new cylinder heads, paid extra for the CNC chamber porting, a custom cam for the engine , all in an effort to improve airflow. Why stop at the carb? If the heads (just throwing numbers out there ) are worth 25hp over the old heads, and the custom cams worth 25 HP over the old cams, what if your carbs are gonna cost you to lose 25hp? When you add it all up the carb upgrade would have been the cheapest power upgrade out of the package. Now if its 10hp then maybe not worth it.
On a 6000rpm 540 with AFR heads and a custom cam, making say around 700hp, you just may see a nice jump in power by bolting on a dominator. 600hp 540, prob not. Have guys made great power with 4150s, of course. Only way to know is to test. If your on the dyno and get your carb tuned at say 12.5 Afr at 6000, and swap it out for a dominator, you'll have to tune the dominator for a 12.5 Afr at 6000 as well for a direct comparison. I've seen where guys did this test, had the 4150 tuned perfect, then slapped a dusty old dominator on with a pig rich setup, see no gains or even losses, and say the dominator sucked. Not a fair comparison.
Money and wanna get boat going because I can swap I takes and carbs mid summer easily... I know the 800's are way to small...
