daver

Ok, a few poeple have said that the b20b crank pulleys are much bigger and heavier than the ls pulley. I've compiled a list of specs comparing my '96 jdm b20b pulley to my '90 ls one. I'm not sure, tho, if the engine even came from a crv (low rise intake mani here) so there could be different b20b pulleys out there. The purpose of this comparison, tho, is for people deciding whether or not its "safe" to use the ls one on the b20b for engine vibration dampening/counter balancing duties. On with the show...

'96 b20b:

weight: 6.75lbs
inner pulley dia: 6 5/8" (alternator)
mid pulley dia: 6 1/4" (a/c)
outer pulley dia: 3 5/8" (p/s)

90 ls

weight: 6.5lbs
inner pulley dia: 5 7/8" (alternator)
mid pulley dia: 5 1/2" (a/c)
outer pulley dia: 3 7/8" (p/s)

All weights are exact- measured on a balance scale and the diameters are measured to the edge of the belt-retaining lip with the exception of the ls p/s lip, which was wider to accomodate a thicker v-groove belt (so i took off 1/4" to equalize it). Also, the actual p/s pump pulleys are the same at 4 1/8", but the b20 alternator pulley is a mystery because the skanks stripped it.

So from this i think the ls pulley will be fine (unless your worried about weight distribution haha), assuming the belts will fit properly. It would probably be better, in fact, to keep the ls alternator spinning slower (unless you have a mega stereo). I have a bunch of spare belts lying around now, so hopefully the slack adjustment can compensate for the b20 pulley and the ls alternator. I chose to keep the b20 pulley because its in much better shape as i can actually see the timing marks. So add a 1/4 lb to the ls weight for all the rust loss. Get the ls pulley...

Conversely the a 92 civic dx crank pulley weighs 4lbs and the diameters are all different, but in the same neighbourhood as the other two (plus it won't fit either, smaller hole).

d

Mista Bone

only use a DX pulley on a 1.5L else risk destroying the main bearings.

daver

(plus it won't fit either, smaller hole).

Mista Bone

I was refering to the 1.6L SOHC folks that like to use a LW pulley and might be tempted to use the DX pulley on a 1.6L.

Here is why..........

daver

some scary pictures. Looks like they're relics from the titanic

b20guy

1/4 lb doesnt seem like much...why then are people saying its "much heavier" and "massive"?
is the 90 ls same as the 94+ ls?
is the 96 jdm b20b same as the usdm b's or z's?
too many variables dammit!

OK, assuming the pulley ratios are good for an LS crank pulley on a B20 block, driving DX accessories, is the 1/4 lb difference (if that's universally true for LS vs. B20 cp weights) enough to cause what you, Bone, are warning us of, re: 1.5 cp on a 1.6 block bearing damage? What was the difference in those SOHC weights that caused that kind of damage. Also is the weight of the crank pulley the ONLY factor in determining a crank pulley's damping effectiveness?

Oh, and Daver, thanks for taking the time for the measurements.

crvcivicsiintegt

so what is the right crank pully to use let me

tinkerbell

sorry, this probly the wrong place to ask, but how can using a lightweight pully cause damage to bearings like this?

thanks,

t..

Mista Bone

the lightweight pulleys do NOT have the extra 4-5 lbs of rubber dampening that is need to control crankshaft vibrations.

With the B motors being "short" stroke motors, they are usually safe.

BUt just look at some of the FAST 9-10 sec. cars, they all run FACTORY dampers.

tinkerbell

my 1st gen B16A does not have ANY rubber dampening at all.

the B20 pulley i have does.

should i not use the un-damped pully?

t..