Alternator question

[dave_s1987]

hey guys, just had a quick question. I finally got my sbc in place and it's time to hook up the accessories. Unfortunately my new motor came with cylinder heads that do not have accessorie mounting holes so I opted to buy brackets to mount it to the water pump.

The brackets got here today and they are too small to fit my alternator. The mounting holes on my alternator are 9 inch apart and the bracket is only 8 inches.

I know this is probably a stupid question but do they make smaller alternators or is my bracket no good?

thanks in advance

 

[Longroof79]

Dave,
Which alternator are you currently using? The reason I ask is because a CS130 alternator has a slightly smaller body than a 12si...and maybe a 10si as well.

I'm guessing you're using a pair of the earlier double hump heads without the accessory holes.

Check out some of streetrod supply shops for assorted brackets

 

[dave_s1987]

Hey thanks for the reposnse. And yes the head are a set of rebuild double hump heads so no accessorie holes for standard mounting unfortunately. i'm assuming it's the 12si or the 10si I have though because it's definitely too big for the new brackets I ordered. I'll have to check it to tomorrow to be sure. Those brackets weren't exactly cheap either so I'm really hoping I can make a deal and trade my old alternator in for a rebuilt without putting out too much cash on top of it. Either that or I'll have to order a second set of of brackets for the bigger alternator.

After figuring out my alternator wasn't going to be mounted today I decided to work on installing my starter instead. Of course the bolt holes don't line up on this either though lol must have a different flywheel on this motor than the one that came with the car. It's just One more thing I'll have to go out and buy I guess.. Just having one of those days today lol

Anyone have any recommendations? Should I get one of those high torque mini starters I keep seeing?

 

[64nailhead]

What is the block from (including year) or casting nmber? Attaching components for SBC's are readily available and usually cheap. Most mini starters work for every block or flexplate application and I'd highly recommend swapping to a CS130 alternator. The biggest issue converting to the CS130 is the mounting ear locations. Most of the older stuff (10SI) is 180 degrees between the ears, whereas the most, not all, CS130's are not.

 

[Longroof79]

Also, when converting over to a CS alternator, it might have to be re-clocked. The vendor I purchased mine from had already clocked it for my installation. The one prior to that was a junkyard alternator that I did have to re-clock it.
Nailhead is correct, the CS alternator you'd need is one with the opposing ears...12 o'clock and six o'clock.

 

[V8 Rumble]

If going cs get one from a 91 ck 1500 7.4l as it is already clocked for 12 and 6 o'clock. I just did this on my malibu. The size difference wasn't significant. Plus you'll need an m8 x 1.25 thread bolt for the top and a sí to cs harness gm part#88861073 also known as pt2145. This harness has the resistor if you have gauges.

You would also need to connect your factory white wire to the fuse box ign terminal or 12v source that comes on to get the alternator to charge of going this route.