BBC pulleys- need a quick lesson

MufflerBearings69 · Posted: Fri Jul 30, 2010 8:48 pm Post subject: BBC pulleys- need a quick lesson

I am swapping out the balancer on the FE, and ATI tells me their balancer uses a BBC pulley.

I was wondering if someone could school me on whether all BBC crank pulleys are pretty much the same or if there are variances to look for in offset and fitment.

Basically, I can count grooves and measure their width, wondering if there are other variables or if they have the nice universal interchange like most SBC stuff seems to.

Thanks

af2 · Posted: Fri Jul 30, 2010 8:58 pm Post subject:

Long and or short water pump?

MufflerBearings69 · Posted: Fri Jul 30, 2010 10:49 pm Post subject:

will that simply change the distance from mounting face to first groove? Seems like 3-bolt mounting is most common?

I sent an email to ATI asking for specifics on the pulley- I want to pull a stocker, blast and powdercoat it and run it. Cant see spending $$$ on a billet pulley, but dont want to go through a few of trials to sort it out.

(especially with the mass amounts of chevy knowledge here!)

Knarley Darley · Member Joined: 22 Apr 2004 Posts: 1149 536969.38 points

On the short pump crank pulley, the first groove is right against the balancer, on the long pump pulley the first groove starts a good distance from the balancer like an inch or some thing like that. One problem I have run into is the diameter is either 7, or 8 inches on the stock pulley which spins everything else pretty hard. If you are making any horsepower the belts will fly off every time you goose it. I usually run a smaller after market crank pulley to slow everything else down a bit, and that has worked good for me.

MufflerBearings69 · Posted: Sat Jul 31, 2010 5:59 am Post subject:

good to know. Sounds like the BBC pulley shouldnt be a hassle so much.

To run my stocker, I have to get the spacer behind machined down .375" and get some sort of adapter/spacer for the pulley... Sounds like more hassle than sorting out if I need a short or long water pump pulley and putting it on

Big Dave · Posted: Sat Jul 31, 2010 1:20 pm Post subject:

First be sure it is a BBC pulley. A lot of used BBC pulleys stared out life on a SBC. You can tell a BBC crank pulley by the size of the hole in the center. Both the SBC and BBC share the same three bolt pattern. The SBC pulley will have a small 5/8th inch diameter hole. The BBC will have a larger over an inch sized hole.

As mentioned there are short water pump and long water pump issues as well as deep and standard Vees in the pulley with a deep V being used on all of the engines equipped with mechanical lifters to keep from throwing the belts. Finally there are differences between A/C and other cars with the difference being the outside diameter which has a matching increased or decreased outside diameter water pump pulley.

So basically there are six different BBC crank pulleys to choose from. Since it is going on a big block Ford I would check the dimensions you need (alignment being more critical than diameter) and search for a pulley by specification.

Big Dave

MufflerBearings69 · Posted: Sat Jul 31, 2010 8:37 pm Post subject:

Awesome. Sounds like I need to get the balancer on the engine, figure out alignment, and find a pulley close to my pulley's diameter. Maybe an aftermarket aluminum pulley will be easier, will have to see what I can find around here Very Happy

Thanks a lot everyone!

Knarley Darley · Member Joined: 22 Apr 2004 Posts: 1149 536969.38 points

The after market Aluminum is the way to go, besides being machined on a lathe so they are true, you can get them in a smaller diameter if it is needed.

MufflerBearings69 · Posted: Thu Aug 05, 2010 3:16 am Post subject:

Well, I am glad I didnt order a pulley yet. ATI balancer is here, and I bolted the outer damper ring to the hub. The face of the hub and the face of the ring are flush.

I then have my center damper bolt and washer to deal with- which are considerably larger in diameter than the 1.100" hole in the typical BBC pulley I was looking at.

I asked them yet again what pulley I need (swp or lwp BBC) and have gotten no reply from email. I have a feeling the guy who answers those has never dealt with the FE (nobody in their right mind does)

So I am going to get the box o' pulleys down and see if the FE pulley bolts up- if so its just offset to worry about...

Why didnt I build something mainstream? Embarassed

MufflerBearings69 · Posted: Wed Aug 18, 2010 1:41 am Post subject:

Ok, so I pulled the Professional Products damper off, got this shiny new ATI piece out, and have put it on the crank with no issues.

Here is where things get odd- the tech guy said I need to run a BBC crank pulley. I cannot see how nor why. I measured the distance from the face of my timing cover to the mounting face of the crank pulley before removing the PP damper- right at 3"

I installed the ATI piece, then torqued all of the bolts that hold the damper to the hub according to their spec, and torqued the crank bolt to spec too, and did the same measurement- 3-1/8" best I can tell.

I know using a straight edge and a tape off the timing cover isnt precision, but belt alignment isnt exactly precision either. I dont throw a ton of weight behind my 1/8" discrepancy since its uncertain how perfect the PP damper lined up.

Ok, so data piece number 2 that should have clicked in my head previous to today- the BBC crank pulley is a 1.100" center bore, while this new damper is stock FE size (didnt measure but same washer under crank bolt leaves same slight lip of hub uncovered)

In short, unless I am missing something, I think the ATI tech guy is mistaken. I dont for a minute claim to think I know better, so I ask what this all sounds like to you guys.

Thanks

10sec.et · Posted: Wed Aug 18, 2010 2:01 am Post subject:

ok, im lost

. what exactly is the problem ? do NONE of your pulleys fit ? what doesnt fit ? can they be re-drilled/machined ? please explain slowly, im easily confused retard

.

MufflerBearings69 · Posted: Wed Aug 18, 2010 12:04 pm Post subject:

Now that I got some sleep finally and stared at it again, I think the only problem is the ATI tech guy... I have to get the accessories all bolted up and try some stock pulleys to see where I am at.

Big Dave · Posted: Thu Aug 19, 2010 12:02 pm Post subject:

I am confused as to why the ATI guy is recommending using a set of Chevy pulleys to start with. It would be mere coincidence that they would line up with the rest of the Ford pulleys. Once again if you get a V-pulley out of alignment the belt will be thrown or at the very least roll as one side tries to climb the wedge of the pulley side because it is pulled that way.

Only reason I can think of to use a Chevy pulley is because they have a Chevy bolt pattern on their balancer to keep from having another part number and part to stock. If that were the case I would redrill the STI balancer for a Ford bolt pattern (though it will void the SFI rating and probably the warranty as well).

Big Dave

MufflerBearings69 · Posted: Thu Aug 19, 2010 8:10 pm Post subject:

You and me both... If I hadnt seen this odd footnote I never would have thought of such an idea.

Didnt get a chance to mock it all up today- hoping to get to it tomorrow early.

MufflerBearings69 · Posted: Fri Aug 20, 2010 12:21 am Post subject:

Got out and mocked it up- everything is good except bolt pattern.

As in, if the FE is on a 3" bolt circle (making up a number for reference) the bolt circle is 2-7/8" I would say. can look down in and see the threaded holes but bolts cannot go in.

So this leads me to a judgement call- Can I just drill the holes out on the pulley? ATI sends some 3/8-16 bolts with 3/8 12-point heads and small flange beneath. Look just like header bolts really. And small washers the same OD as the head of the bolts.

Seems to me I can drill the pulley out and get some good grade 8 SAE washers that will cover nicely and run it?

Thoughts? I was going to call ATI but I dont think they even know what the deal is with this part.