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Author Topic:   Alternators - to have or not to have?
posted July 23, 2001 02:13 PM
I'm wondering what you guys do as far as alternators. If you don't run one, what type battery do you use? I'm having a lot of trouble throwing belts and while I know that it would be a band-aid, but I'm thinking of just removing that belt. I have one in between the crank and water pump, but when the alternator belt flies off, half the time it gets underneath the water pump belt and throws it too. Also, any advice on keeping my belts on would be appreciated. This problem came out of the clear blue nothin' and we've tried everthing to get things lined back up.

Al Sherfield
posted July 23, 2001 04:58 PM
Have you tried using a oversized deep groove pulley? It reduces the speed your alt. runs at. I haven't had a problem.

posted July 23, 2001 05:33 PM
Throw that alternator away!
Take it from someone with alot of thrown belt experience I went to the local parts store bought a namebrand 1000cca battery tossed it in the trunk I charge once a week the day before I race (sometimes the day of!) and I have'nt had a problem with the HEI on that SBC since.One note besure you have a good ground on the engine to the frame.
For three years I've been fighting belt problems,this year our rules were changed as to allow aluminum pulleys-Yea!! I made a few changes.
1.Switched to the short pump(corvette) this eliminated the extra weight off the front of the motor.
2. I purchased a aluminum pulley set (25% reduction)make sure it comes with the belts.
3.I shortened the spacer on the fan and extended the aluminum fan shroud back to compensate (I make my own shrouds)
4.I went out and got a PS pump off of a late 70's GM van (make sure it has a two groove pulley) they mount low on the block on the two lower tapped holes on front and one to the exhaust.
With that pump I was able to use the same size belt for both the water pump and the power steering (the belts are only 32" long.
I did this and have'nt thrown a belt since and I run my engines pleny hard for a hobby stock(6900rpm)

Hope that was insightful!
Good luck,Dryslickracer

posted July 23, 2001 05:43 PM
Go with the 25% reduction alum crank pulley and one of the Gel Batteries, good against vibration. has the Interstate Gel Batteries for $89.00 last I checked. Just charge the day before or day of and will be good to go. If in doubt, throw the alternator out!

posted July 23, 2001 06:30 PM
Hey guys...if you run a HEI G.M. distributor it is designed to run on 13.8 to 14.2 volts and will produce a better spark at that voltage. By all means run an alternator.

If you run a short G.M. pump, Speedway has a roadster mount tht puts the alt. on the intake side of the valve cover and out of the way. Also run a big pulley like the one Moroso supplies and you won't have any trouble.

Take my word as I have been both ways, An alternator is better.

The Peddler.

posted July 24, 2001 11:03 AM
loose the alternator and get a good coil and modualr what you will gain in voltage is not worth what you loose from the drag of pulling an alternator

posted July 24, 2001 11:17 AM
As usual, I left a few things out. I run a Proform HEI racing distributor w/an MSD module. Wih the alternator connected, I have 14V on the voltmeter.

Does Speedway have the deeper Moroso pulley? Did you just use that on the alternator with no other changes? I would like to keep the alternator for my own peace of mind, but I don't want to keep it unneccessarily.

[This message has been edited by WesternAuto17 (edited July 24, 2001).]

posted July 24, 2001 11:38 AM
Running the MSD is even more reason to run the alt. Battery voltage can be decieving sometimes. I have seen heavy batteries produce 250 to 300 amps (enough to start most motors) and have a static voltage of less than 12. Your electronic ignition devices need 13.4 to 14.2 volt for optimum performance. Point is, just because your battery will turn the starter, doesn't mean it is charged or has the voltage to run the electronics properly. You would be supprised at the performance difference with the proper voltage to these electronics. Run an alternator and keep the battery charged.

posted July 24, 2001 08:46 PM
I used to do what Peddler did charged my battery before we race. This year my dad decided he wanted to try to run an alternator. He welded a bracket on the rear end and that is where we run it. It runs off the drive shaft. Works great so far. We have been on bumpy and smooth tracks and so far belt is still there. We run a light so if it does stop charging I know something is wrong.

3x Racing
posted July 25, 2001 02:45 AM
I'm wondering what evidence the guys who say to loose the alternator are basing their 'expert' opinions on?? If you can't gain enough power from having that extra 2-4 volts of juice to your coil to compensate for the little bit of drag you get when you run a proper pulley, then throw your HEI in the trash because its BAD!!
I've worked for an engine builder with a dyno for about 3 years and trust me, I've done the testing, RUN THE ALTERNATOR. Get a racing style, one-wire type with the proper deep groove pulley and give your HEI the juice it needs. Every volt into your coil puts out about 50,000 or so volts depending on your coil type. So no alternator means your giving up 100,000 to 200,000 volts at the plug. You must have on **** of an engine to be able to handicap yourself so bad!

posted July 25, 2001 10:51 AM
Alright, I'm convince that I need to keep the stupid thing. Now where can I get these deep groove pulleys you all like so much?

posted July 25, 2001 07:20 PM
Looking around the pits at my track, there are more guys not using alternators than do. I see alot of the dry cell/Optima type batteries, and I haven't seen any of the alternator guys kicking the other guys butts yet. Spend all the time you want on the dyno, results at the track is what made the decision easy for me.

posted July 26, 2001 06:51 PM
Anyone who deals with Moroso parts can supply the pulley.
As far as no one running an alternator, I will say this,,, I have seen the amount of voltage drop on a HEI without the proper voltage input. I have also done the research on the voltage drop off with a HEI above 4500RPMs. Don't run an alt. OK by me,but when the car won't start because you forgot to charge the battery, or the engine starts misfiring because of low battery voltage don't say a word.
Racing is expensive and exhaustive and the more things I can do to make it easier the better.
Have fun
The Peddler

posted August 02, 2001 09:44 AM
peddlers right run it. its said that u lose about 7 horses with using one well the volts that it makes will give u more that 7 in the end. also if u dont use one ur battery wont last but a few seasons due to the constant charge and drain unless u fork out the money for a top of the line batt later scott

posted August 20, 2001 09:08 PM
dont run one you loose hp get a 1000 cranking amp battery

posted August 21, 2001 10:07 AM
hesse if you are smart you can make it so you will never have to pay for another battery again just get a 1000cca from a parts store that has a two year replacement thats waht i did have had a new batery every year and not payed a penny for it i do the same with starters just don't let them know it's in your racer tell them it's for your truck. i have a buddy that mysteriously has the clutch go out of his truck every spring too lol just like the old saying goes cheat a littl lie alot and win a few

posted August 21, 2001 10:22 PM
yep mine has a 3 year limmited warrantey and i have never had any trouble

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