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Discussion Starter #1
Done some reading tonight and it looks like I need to upgrade my ignition system from a 7AL-2 to a MSD-10 plus or Super Mag 4.


What are the pros and cons going with the MSD and the Mag? I am not running a delay box or anything other than a RPM activated switch, so the limited functions of the Mag won't be too big of a deal, at least today.

How much hp or consistency do you think I am leaving on the table with the 7AL-2?
 

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Dont even waste your time, just go with a MSD 25 amp mag. If ur running any kind of boost(25 psi++) at all the MSD 10,MSD8 or msd7 will not fire it correctly and tuning will be a real bitch.....period...Ive built dozens of blown alcohol motors and just Forget the box and put a mag in it ...if ur running 15 lbs or so it might work. if ur running 44psi +go with a 44 mag
 

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Discussion Starter #3 (Edited)
Great input thanks. I am at 1:1 now at about 15psi. I have a 15% over combo I plan on putting on as soon as I have all the other bugs worked out, which I am guessing will put me near 20 psi. I can not say I won't turn it up even more one of these days though. I would need a bigger huffer if I wanted to get over 25psi. Its a 12:1 motor so don't know that I would need much more than 25 psi.

And yes tuning has been a bare with the 7AL. No wonder I am not burning all the fuel in the motor. :)
 

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If it has a Blower it needs a Mag. Don't mess with anything else. Now get them doggies movin YA.....:|err
 

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Discussion Starter #5 (Edited)
Aye Aye captain, a mag it is. Are used ones worth picking up? And if so is there a good place to look for a refurbished one?

Arent the MSD-10+ boxes supposed to have 700mj of spark output for 30degs... thats more than most mags? I get concerned of battery life with the 20 amps of current the box needs though.
 

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blower

I have a blown bbc im making 1400hp at 20psi and i run a msd 7al2 and havent had any problem tunning the motor and runs great, i have heard of having some trouble starting a blown alky motor without a mag. I also know people that run blown alcohol motors with msd 7al boxes its really all about how much cash you have mags cost a good bit
 

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go with a mag the msd box uses 1-2 amps per 1000 rpm`s
a mag does not use any, it makes it.

you get twice as much fire at the plug with a hopped up super mag 3
as you would get with the 7al2 plus you have that draw w/ msd box

now if you have money to burn go with msd mag
JMO
 

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New to blown alcohol myself. Last season we ran a couple races with the motor out of the K5 and it had a MSD pro mag in it. Worked really well so that's what we put in our engine. All the benefits of a mag with a rev limiter and the ability to use a crank trigger and/or a MSD digital box if you want. Pick your size and go with a winner!!
 

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getting ready to drop a 8-71 on my 540, still debating on gas or alchol. motor has msd 6al. wondering dose the same apply to gas as alchol on ignition systems. also will any mag work (joe hunt, vertex, malory sprint mags)?:)hand
 

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getting ready to drop a 8-71 on my 540, still debating on gas or alchol. motor has msd 6al. wondering dose the same apply to gas as alchol on ignition systems. also will any mag work (joe hunt, vertex, malory sprint mags)?:)hand
If you are going to run alky go with at least a 5 amp mag, I am not sure what a super mag put's out ,, what compression is the motor ? how fast are you going to run the blower ? I had problem's with a joe hunt,, just not enough zap,, a friend run's a 7al box and doesn't seem to have any trouble,, ...................Eric:)
 

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Discussion Starter #11
getting ready to drop a 8-71 on my 540, still debating on gas or alchol. motor has msd 6al. wondering dose the same apply to gas as alchol on ignition systems. also will any mag work (joe hunt, vertex, malory sprint mags)?:)hand
From the Magneto FAQ http://www.fuelinjectionenterprises.com/

Circle track: Standard OAC Vertex or Sprint Mag (up to 2.5 amps)
Street/Hot Rod: Any standard OAC Vertex or Sprint mag
Blown gas: 2-3 amp Vertex or Super Mag 2
Mild Blown alcohol (up to 10 PSI of boost): 3 amp Vertex or Super Mag 3
Moderate Blown Alcohol (up to 20 PSI boost): 4 amp Vertex or Super Mag 4
Hard core Blown alcohol (~30 PSI boost): 6 amp OXC Vertex or 6 amp Super Mag 5
Injected Nitro (50%): 4 amp Vertex or Super Mag 4
Injected nitro (up to 100%): 6 amp OXC Vertex or 6 amp Super Mag 5
Blown nitro: 7-8 amp Super Mag 5


I found a used Super Mag 4 that I just bought for mine.
 

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From the Magneto FAQ http://www.fuelinjectionenterprises.com/

Circle track: Standard OAC Vertex or Sprint Mag (up to 2.5 amps)
Street/Hot Rod: Any standard OAC Vertex or Sprint mag
Blown gas: 2-3 amp Vertex or Super Mag 2
Mild Blown alcohol (up to 10 PSI of boost): 3 amp Vertex or Super Mag 3
Moderate Blown Alcohol (up to 20 PSI boost): 4 amp Vertex or Super Mag 4
Hard core Blown alcohol (~30 PSI boost): 6 amp OXC Vertex or 6 amp Super Mag 5
Injected Nitro (50%): 4 amp Vertex or Super Mag 4
Injected nitro (up to 100%): 6 amp OXC Vertex or 6 amp Super Mag 5
Blown nitro: 7-8 amp Super Mag 5


I found a used Super Mag 4 that I just bought for mine.
Nice find on the info,, I can see why I was having problem's, (oac hunt ~18lbs of boost ) Have a pro mag 12 now ,, glad U found a mag to use ,,........Eric:)hand
 
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Never take the Stairs, if the Elevator is working, If you can afford a Fuel setup, use it, theres no loss in to Much mag, and there is Plenty if the Hole wont Fire, I have seen some Mags and Wires only last a short time, and I believe using the most powerful setup right off eliminates some of the guess work, standard fare for me is to have One Mag setup in the Boat, one in the trailer, and one at MSD being checked, same with a fuel pump and I did an Enormous amount of NDT on our engines and driveline back in the 80's, I also balanced Every Rotating part on the Boat....I mean Everything, and most were done seperatly so if we lost something and had to replace it we didnt have to rebalance an entire assy. I also used 3% over on Crank assemblies. IMHO
 

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If you are going to run alky go with at least a 5 amp mag, I am not sure what a super mag put's out ,, what compression is the motor ? how fast are you going to run the blower ? I had problem's with a joe hunt,, just not enough zap,, a friend run's a 7al box and doesn't seem to have any trouble,, ...................Eric:)
my motor right now is 10:1 unblown. was thinking of adding the blower w/ miner changes and running e-85 w/ 10-15lbs boost, or changing the compression to 8.5:1 and running gas (10-12lbs boost race fuel and 6-8lbs boost pump gas) . this boat will see every weekend at the afterbay/lake and racing duty as my schedule allows.:)
 

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my motor right now is 10:1 unblown. was thinking of adding the blower w/ miner changes and running e-85 w/ 10-15lbs boost, or changing the compression to 8.5:1 and running gas (10-12lbs boost race fuel and 6-8lbs boost pump gas) . this boat will see every weekend at the afterbay/lake and racing duty as my schedule allows.:)
Are the piston's nitrous or blower piston's ? what type of fuel delivery on top of the blower ? how much hp do you want to make (ballpark ) ? would you be racing a bracket ( what are you shooting for ) ? ...Eric
 

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Are the piston's nitrous or blower piston's ? what type of fuel delivery on top of the blower ? how much hp do you want to make (ballpark ) ? would you be racing a bracket ( what are you shooting for ) ? ...Eric

the pistons are mahle flat tops, i have two dominators or a was thinking of a bug catcher. im wanting to make about 1000 hp, and go race were ever i fall in a bracket (njba). if i run gas, im goin to set it up to run pump gas at the lake and race gas and more bost for the races.
 

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my motor right now is 10:1 unblown. was thinking of adding the blower w/ miner changes and running e-85 w/ 10-15lbs boost, or changing the compression to 8.5:1 and running gas (10-12lbs boost race fuel and 6-8lbs boost pump gas) . this boat will see every weekend at the afterbay/lake and racing duty as my schedule allows.:)
Don't know anything about E-85, but put an 8-71 on your motor as is, about 5 lbs boost on methanol and you'll make 1000+ HP easy. Our combination is very similar to this. In a decent flat, you should run 8.0's pretty easy with 1000 HP.
 
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I dont believe any engine will live or be reliable with 6-8 psi boost on 93 Octane pump gas, I built a 509 BBC with a B&M Mega Blower for the American Offshore Bunch when they had a shop in Grove Oklahoma, the boat had a 14X34 pitch prop and was radar clocked at 104MPH in a 26' cat, but Ed the owner tried using Av Gas or some other cheaper fuel and ended up murdering the engine, (Head Gaskets, ring lands, and more) then went to another engine shop and did the same thing,..................you cant make Chicken Salad out of Chicken crap
 

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I dont believe any engine will live or be reliable with 6-8 psi boost on 93 Octane pump gas

i have a friend who is running pump gas and 8lbs of boost (28* lock timing) on a gm performance parts crate 502. he had it in a southwind tunnel jet,ran two seasons before pulling the motor to sell the boat.:)
 

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I dont believe any engine will live or be reliable with 6-8 psi boost on 93 Octane pump gas, I built a 509 BBC with a B&M Mega Blower for the American Offshore Bunch when they had a shop in Grove Oklahoma, the boat had a 14X34 pitch prop and was radar clocked at 104MPH in a 26' cat, but Ed the owner tried using Av Gas or some other cheaper fuel and ended up murdering the engine, (Head Gaskets, ring lands, and more) then went to another engine shop and did the same thing,..................you cant make Chicken Salad out of Chicken crap
That all depends on your methods. The B&M isnt a real efficient blower from what I've read, I dont have any experience with them.
With my little turbo engine I've ran as much as 15psi on 91octain-crap pump gas and the plugs looked great. But mine has an air to water intercooler also. I run 12psi all the time with no problems. How much timing was he running in it ? Mine starts at about 34 and drops to 28 when the boost comes on.
 
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