Bigeddie

Fellas my radiator decided to burst open and i decided to upgrade to alum radiator and dual fans.. that being said i will need to upgrade my alt. The cs-144 option won't be able to work for me because i have tall valve covers.i will be getting a 140 amp alt don't know which but i know i need to upgrade my wiring or at least add wires or something. Someone please tell me what to do give me a checklist. I've read like 20 of these and i cannot wrap my brain around it because the thread sometimes turns into people "debating" about what way is better. So anyone that has done this please help

cagotzmann

I went with a serpintine kit
https://www.corvetteforum.com/forums...n-my-78-a.html
The alternator in the kit is the following
http://www.summitracing.com/int/part...2464/overview/
It is wired to the existing stock system with no modifications.
I am using the dewitts dual spal setup. The only mod is the electric fan connections for the dual spal setup.

Bigeddie

I forgot to mention I have a pretty nice system and just bought the"speed direct" headlight harness and will eventually upgrade my headlights

terrys6t8roadster

I have the dual spal fans, a radio upgrade, and who knows what else will be added over the years. JEGS sells a kit to upgrade the Delcotron alt to a 100A output for $40. This winter I will be replacing the output wire from alt to starter with a larger guage. T

resdoggie

I removed my a/c but still have the three pullies. I moved my alt forward to run off the centre pulley which had been used for the a/c belt. I also used a billet alum alt bracket which uses two bolts on the front of the head on the left side. You will get the required clearance for your vv covers if your setup is similar. I have the std 63A alt.

REELAV8R

Mostly your concern for more power from the alternator will be at idle RPM's. Probably any alternator would do the job above 2000 RPM.

140 amps would be more than you would need with electric fans IMO.

I put in a 110 amp alternator 3 wire set up (same as stock) It's still a 10si alternator so same dimensions as stock and produces 65 amps at a 600 RPM idle with full output achieved by 1200 RPM.
I run two 11" cooling fans that draw15 amps apiece while running (25 amp start up). Even at idle, voltage never falls below 13ish +volts. This is with lights on and A/C also running. I don't have any other big draw items on the car like a sub woofer so this alternator with stock wiring works fine.
Bought it on ebay, chrome exterior $69. similar to this one.
http://www.ebay.com/itm/NEW-CHROME-BBC-SBC-CHEVY-ALTERNATOR-110-AMP-3-WIRE-HO-/131109927929?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e86c2bbf9&vxp=mtr
Of course it has Chinese components and is probably made there so your results may vary.

74modified

When I upgraded, I swapped out my ammeter (74) for a voltmeter because I was adding several new circuits and a much larger output alternator. You don’t always need to do this – I am sure some will disagree. With just the fans, you should at least upgrade the alternator output wire to match the max current of the new unit. The new supply to the fan relays is where you should be careful. Pull from somewhere that will not overload existing circuits.

speedreed8

i used a cs130 also from local alternator/starter repair shop. just swapped pulleys from old alt.(v belt) to the new one. bolted right in place with stock brackets. i run my dual spals directly off the alt..w/ 10 ga. wire,& circuit brks. through 2 relays. i also added an additional 10 ga. wire and fuse link, paralleling the oem charge wire down to the starter + bolt. just for added insurance, because the fans will run with just the key on(when eng. is hot) and is pulling just off the battery...

mikep3

CS130, 105 amp, I run AC and dual fans with no problem at idle. The 10SI OR 12SI units just do not perform like the CS130...

Bigeddie

Fellas like i said will be going a different route with alternator. i was asking about upgrading wires and making sure the extra current with new alt doesn't burn up anything.do i just wire dual fans to alt? what about my sound system

jb78L-82

Post #8 is your answer-from Speedreed8. Wire directly to the alternator with relays and a parallel 10 GA wire to the positive of the starter along with the stock OEM wire to the starter…Done. Relatively easy and a little overkill on the starter wire+OEM starter wire but smart insurance….

The13Bats

I did this on my 69 and the new wire I ran was...hum...the gauge was 10 I believe it was large and many said overkill but that in this case in far better than undercut.
I ran it a stupid long way when the car gets back I am going to go shorter with it...

hipocars1

Here's the "Recommended Minimum Charging Cable Gauge Size"
chart published in the Delco Remy Service Test Specifications, Bulletin No. 1G-187, dated 1/1/77.

doorgunner

I bought a 140 amp Jegs alternator that had the same bolt pattern as the original alternator (I may have re-clocked it so the connector wouldn't be facing the exhaust manifold). I removed the serpentine pulley and installed the Corvette V-pulley onto the new alternator. I modified the lower alternator bracket to move the alternator away from the tall valve cover and the exhaust manifold. Then I lengthened the upper bracket that has the adjustment slot so the new longer belt would tighten correctly.

The old alternator & the "new" 130 amp units....






I found a nice chrome alternator bracket under 4 different layers of paint once the old alternator was out of the car...






The pulleys have been swapped (I set the serpentine pulley on the old alternator just to keep track of it).....






The 140amp Alt. is in place....I did flip the chrome bracket to move the alternator away from the tall valve covers and lower it about 4 inches because the bottom of the alternator was rubbing the corner of the valve cover---It also sat "too high" for my liking. It is now a safe distance above/away from the exhaust manifold.





The members above list the wiring upgrades....it's up to you as to which wiring method you choose.

7t9l82

i used the 110 amp alt and ran a separate wire from the alternator to the starter. i upgraded my headlights with the danial stern components and made my own harness. i used wiring components from a marine electronics store.it wasn't hard and much cheaper than the kitwww.danielsternlighting.com/