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Thunderbolt.......any upgrades?
I've got a 1990 (91?) fairly stock 454 mag. The only upgrade is a slightly larger carb than stock (I think it's Holley dp 750 or so?). It is possible there could have been a mild cam upgrade in the past, but not sure of this (ie. timing cover and intake had been removed at some point and a super nice lopey idle.)
Anyway, boat runs great.........I've never touched the ignition system. I know the thunderbolt is a very good and reliable system. Are there any minor changes to the ignition system that might be recommended (for reliability and/or performance)? What about the coil? Fuel: 87, 91, 93 octane? Sure get a lot different info on this one. Thanks! :ernaehrung004: |
Originally Posted by bigbang
(Post 3647721)
I've got a 1990 (91?) fairly stock 454 mag. The only upgrade is a slightly larger carb than stock (I think it's Holley dp 750 or so?). It is possible there could have been a mild cam upgrade in the past, but not sure of this (ie. timing cover and intake had been removed at some point and a super nice lopey idle.)
Anyway, boat runs great.........I've never touched the ignition system. I know the thunderbolt is a very good and reliable system. Are there any minor changes to the ignition system that might be recommended (for reliability and/or performance)? What about the coil? Fuel: 87, 91, 93 octane? Sure get a lot different info on this one. Thanks! :ernaehrung004: |
Yeah, I've got some high end plug wires on it already.......and I'm running ac r43ts plugs. Didn't know if a different coil would be any better, or if there's anything under the cap that could be improved.
Thanks. |
Originally Posted by bigbang
(Post 3647721)
Anyway, boat runs great.........
http://www.mercurymarine.com/service...?category=fuel |
Originally Posted by offthefront
(Post 3647773)
If aint broke dont fix it .....if there has not much modifications I would think 91 would be fine ...original Merc specs say you can run 87 .....m
http://www.mercurymarine.com/service...?category=fuel Yeah, I think 87 gas can be a bit dicey, since the quality and true octane content from the refinery can vary considerably. At $5 a gallon, what's another 10 cents for better gas. |
Originally Posted by bigbang
(Post 3647721)
Anyway, boat runs great.........I've never touched the ignition system. I know the thunderbolt is a very good and reliable system. Are there any minor changes to the ignition system that might be recommended (for reliability and/or performance)? What about the coil?
Thanks! :ernaehrung004: |
Fixx
Originally Posted by bigbang
(Post 3647815)
exactly, you're boat must have been broken when you put pro-charges on it. :rolleyes:
Yeah, i think 87 gas can be a bit dicey, since the quality and true octane content from the refinery can vary considerably. At $5 a gallon, what's another 10 cents for better gas. |
Originally Posted by Rookie
(Post 3648013)
If it is stock I would not change anything with the ignition. If you were spinning 6000RPM then I would consider something else. The thunderbolt is more than adequate and efficient for you setup. Also if you start bumping up the octane in your mag you might have a problem with black soot building up on your transom.
Also, gas doesn't very. That is just myth. It is actually always higher octane than stated. Don't want to start in that topic but it's established. |
Originally Posted by bigbang
(Post 3647721)
I've got a 1990 (91?) fairly stock 454 mag. The only upgrade is a slightly larger carb than stock (I think it's Holley dp 750 or so?). It is possible there could have been a mild cam upgrade in the past, but not sure of this (ie. timing cover and intake had been removed at some point and a super nice lopey idle.)
Anyway, boat runs great.........I've never touched the ignition system. I know the thunderbolt is a very good and reliable system. Are there any minor changes to the ignition system that might be recommended (for reliability and/or performance)? What about the coil? Fuel: 87, 91, 93 octane? Sure get a lot different info on this one. Thanks! :ernaehrung004: |
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