[1970 SS L78]

I purchased a Quanta alternator belt (Number 29-B-603) for my L78 because their belts are supposed to be the most authentic available. Since I'm not using the smog pump the belt is too long. I wold like to use another shorter Quanta belt to match the power steering belt. My inquires for a shorter similar belt haven't been successful. What are you using for an alternator belt for your L78? Size, brand, part number? Thanks.

 

[blm]

Just run a piece of string around the same path as the belt then measure the length of string.

 

[1970 SS L78]

I did the string and came up with 43.5 inches but haven't heard back from Quanta. I really don't want to go to a chain auto parts store and have the kid at the computer come up with a Gates ribbed belt for the alternator that won't match with the Quanta power steering belt.

 

[vortec710]

BEWARE OF CHAIN AUTO PARTS STORE CHILDREN ON COMPUTERS......went to AZone for non-specific parts, JR. had to enter my 70 454...can't be,... the largest motor shown for your rear end lube is 5.7L. Ya gotta love it,.... can't even read cursive but the computer knows all, tells all...what a wonderful world we live in.

 

[Droptop72]

I keep very detailed records of where the donor parts from my project vehicles came from so that when I order parts (which is seldom done at the counter anyway), I just give the make model and year of the donor vehicle and save both of us a lot of confusion and frustration. I also keep an extensive list of part numbers that goes with the vehicle wherever it goes.

 

[71350SS]

To the OP if you measure around the pulleys use a piece of rope that is near to the width of the belt you need so its close to fitting the pulleys.Then you can check on Rock auto more information:

More Information for DAYCO 15395

On the above link you'll see the belt measurement in inches and you can check all the different combo's for the belt length you need then cross reference it to the brand you're looking for.I'm not recommending you buy it but you can use the available info for research.They also list OE part numbers so that might help too.
19 years ago I had a longtime Napa employee tell me that "no way no how" did Chevy ever make an El Camino with a 350 in 1971 when I needed motor mounts for my 400 rebuild. His computer said 6 cyl, 307,or 454 V8's.IDK if Napa cleaned that confusion up by now but I hope they did. Finally I said just order me a set of MM's for a Chevelle with a 350 and said to him " I'll take the blame if they're wrong" and won't bring them back.God only knows what he would have said if I told him they were going on a 400Cube SBC.

 

[1970 SS L78]

Thanks for the help. I finally heard back from Quanta and the B-621belt for a 1971 Chevelle big block measures 3/8 x 43.7 and should work for me. It will look like the power steering belt.

When looking for parts for my 69 Z28, I had a couple of counter guys tell me a 302 is a Ford engine.Hmmm....

 

[LeoP]

I did the string and came up with 43.5 inches but haven't heard back from Quanta. I really don't want to go to a chain auto parts store and have the kid at the computer come up with a Gates ribbed belt for the alternator that won't match with the Quanta power steering belt.

Go to a NAPA store with your measurement!!

 

[Jayhawk500]

BEWARE OF CHAIN AUTO PARTS STORE CHILDREN ON COMPUTERS......went to AZone for non-specific parts, JR. had to enter my 70 454...can't be,... the largest motor shown for your rear end lube is 5.7L. Ya gotta love it,.... can't even read cursive but the computer knows all, tells all...what a wonderful world we live in.

This is the same issue I'm running into when tying to find rear springs for my 70. No engine sizes over 350. What another cancel culture item? If its not in the computers, it never exsisted.....