Q about amperage to run a 4 pill

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projectcop
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Q about amperage to run a 4 pill

#372210

Post by projectcop »

Hi all;
I am getting ready to do a radio install in my 98 corvette. I am considering running a 4 pill amp (wont use it a lot) along with a cobra 148. I have worked out in my mind all of the things I need to do a no-hole install.
My only question is about the alternator. The alternator in my car is rated at 105 amps; and the optional alternators available from the factory were 120 and 140 amps. I have seen up to 200 amp alternators on-line available for this car.
Will my 105 handle a 4 pill? Or should I get a higher amp alternator? And if so, which one? I know that if I use a bigger alternator, I should use a heavier guage charge wire, but how big?
Any help would be appreciated.
Thanks all
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015reddog
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#372211

Post by 015reddog »

I'm pretty sure you would need to go bigger. The question is how big? I am thinking about changing the alt in my car from about the same as yours to a 200 amp. I'm thinking at least 50 amps more than what your car needs by itself. I'll be running a 1x4 in mine. I'm sure someone that knows more than I do will chime in soon.
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MDYoungblood
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#372218

Post by MDYoungblood »

I believe I would rethink a 4 pill and go with a 2 pill instead. The electronics in the 98 Vette' aren't shielded well to begin with, keying a 4 pill might stop it in its tracks. Your main concern should be to get the antenna problem straightened out first.
Yes go with a bigger alternator, let the battery start the car and then the alternator run it.

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ogdoa
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#372223

Post by ogdoa »

All that fiberglass aint going to shield anything and if its a newer one you may have computer problems. Someone told me that I would have problems running one in my explorer because of shielding....I can just imagine how much worse it would be in a vette.
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PA629

#372227

Post by PA629 »

My experience FWIW.

I have a 4x2879 Class C comp-style amp driven by a dual final Galaxy export radio. This same set-up was used in two different vehicles. The first was a 4 cylinder Dodge sedan with a small CCA battery, 95A alternator, and 8 ga. wiring direct to the battery. The second vehicle was a 6 cyl. Chevy SUV with a larger CCA battery, 150A alternator, and 4 ga. wiring, also direct to battery. The output wattage was exactly the same for each vehicle, as observed using the same meter for both. You can draw your own conclusion, YMMV. :icon_e_wink:
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projectcop
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#372259

Post by projectcop »

Hmmm,
I do have an older 2 pill lying around here somewhere; but maybe I'll just run the 148F with the RFX85. The antenna issue will be solved by putting a trailer hitch on the car and attaching the antenna directly to the hitch, so that should work out ok.
I'm wondering if a bunch of ferrite cores on the coax would help?
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southwind

#372261

Post by southwind »

:bounce: A lot of good suggestions here, but with a good antenna system and either 6 or 8 gauge wire, you should be able to skip with no problem. With a good pounding radio and close to 100 watts you should have a good mobile set-up and less potential problems. JMHO. :cheers:
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1206FL
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#372262

Post by 1206FL »

Don't use an rfx85 if you can help it. If you intend to go that route get the rfx150. Much easier to install. Gotta have fans on the back though. JMHO.
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KP68
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#372272

Post by KP68 »

All depends on how hard you're going to drive the amp. If you're going to run it like most CB'ers, as a general rule of thumb, roughly 20 amps per pill. (2879's.)
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