Anyone convert from carb to FI?
09-24-2022 | 09:08 AM
#11
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Joined: Dec 2013
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From: Greenfield, Me.
Has anyone attempted a lean cruise tune?
I’ve also seen some car guys do it. Apparently the exhaust valve gets hot. Also some Aussie cars were tuned like this from the factory.
I think youd find your common cruising RPM and look at the map sensor to dial out like 5% fuel? Not sure how lean you could go. I’m still around 2/3 max fuel rate at my cruise RPMs.
I’ve also seen some car guys do it. Apparently the exhaust valve gets hot. Also some Aussie cars were tuned like this from the factory.
I think youd find your common cruising RPM and look at the map sensor to dial out like 5% fuel? Not sure how lean you could go. I’m still around 2/3 max fuel rate at my cruise RPMs.
Boat motors don't equate to cars, as boat motors are always under heavy load,....
09-24-2022 | 09:14 AM
#12
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If carb and FI are tuned to same AFR there are zero difference to fuel consumption. You can install AFR gauge in your boat and tune carb perfectly. I had Baja 29 OL with twin 600hp carb motors, holley 950’s. I tuned it 14.5AFR idle, 3000-4000rpm 13.2-12.8AFR, 4000-WOT 12.7-12.0. Four channel EGT gauge help tuning alot. Egt was in all situations below 700Celsius. It tell how rich you must go.
09-24-2022 | 10:07 AM
#13
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From: St. Pete Beach, FL
09-24-2022 | 12:01 PM
#14
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From: Chicago
If carb and FI are tuned to same AFR there are zero difference to fuel consumption. You can install AFR gauge in your boat and tune carb perfectly. I had Baja 29 OL with twin 600hp carb motors, holley 950’s. I tuned it 14.5AFR idle, 3000-4000rpm 13.2-12.8AFR, 4000-WOT 12.7-12.0. Four channel EGT gauge help tuning alot. Egt was in all situations below 700Celsius. It tell how rich you must go.
09-24-2022 | 12:12 PM
#15
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From: On A Dirt Floor
I have my carb’s and others tuned in well.
I figure it's easier to save 30-50% or more in fuel costs by getting (voting) Uncle Pedophile and his cronies out of office. In fact will save that and more on everything else to.
Political ? Yes ! Real info on subject ? Yes !
Fuel injection has it’s place. So don’t carbs. In general, not exceptions, what ever you or your engine tuner can tune best, is what is better.
:wink
I figure it's easier to save 30-50% or more in fuel costs by getting (voting) Uncle Pedophile and his cronies out of office. In fact will save that and more on everything else to.
Political ? Yes ! Real info on subject ? Yes !
Fuel injection has it’s place. So don’t carbs. In general, not exceptions, what ever you or your engine tuner can tune best, is what is better.
:wink
09-24-2022 | 12:51 PM
#16
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From: Finland
After i replied to this thread about bbc intakes poor fuel distribution, i went for a ride and boom. Cyl 3 spark plug exploded. Luckily only at 3500rpm cruising speed. Hopefully it was caused by loose spark plug
09-24-2022 | 01:48 PM
#18
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From: Taunton Ma
maybe it’s the angle of the pic, but that ground strap looks like it has rust on it. I’ve seen plugs come apart like that from water and detonation
09-24-2022 | 02:05 PM
#19
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From: Indiana
Fuel injection is nice with out a doubt. Do you save enough to justify the expense of conversion? I doubt it, but there are other reasons to go FI. I still say gasoline is the cheapest part of boat ownership. Enjoy!
09-24-2022 | 03:29 PM
#20
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From: NW Michigan
I faced the decision on my NA 565 builds. I chose old school because that’s what I am and know. I have 2 circuit 1150’s that are crisp and Valako did a tremendous job not only with the porting but all burning very close. All plugs near identical. If your savvy with the FAST type systems go for it and I’m sure you’ll be happy but you’ll also have a bunch of time and money into it. Be easy to do the math on the fuel saved vs the cost of. Definitely not going to pay off for years.
JMO
JMO
