D1SC 8 to 12 rib worth it?
 

Ok, to make a long story short...421ci stroker,D1SC,3.4" pulley.Usual belt slippage issues.2 men & a small boy to get a 63" belt on it.Would get 12 maybe 13lbs for awhile until it started to stretch but at least it was better then 10.Yes I was very well aware of what could happen but it was good for 3 summers!
Broke the snout off last Sept,luckily I wasn't racing it & happened at low rpm so no other damage.Was a Scat 4340 crank.
So now will upgrade to their Pro Series with a big block snout.Was going to do cogs but Procharger says the D series can't handle it.
I will eventually upgrade to the F1 blower (hopefully break the 1,000HP barrier! makes 800 now) Will do the cogs then.
The 12 rib set up is $1100 here (Canadian, yeah s--t a-s exchange rate!!)
It "should" be a little better at least,but $1100 better?? Don't know when I'll do the F series upgrade,might not be for a couple years.
Did a lot of searching on here, seems like the 12 rib with a spring loaded tensioner is pretty good.

Found this thread pretty informative --- https://www.thirdgen.org/forums/powe...ht=d1sc+12+rib

Seeing if anybody has more recent info etc on the 12 rib with aftermarket spring tensioner. Pics & part numbers are the best! It looks like it fits but it's tight. I also have a Ron Davis radiator. Already changed the drivers side fan to one of their slimmer fans to clear the idler pulleys.

Thanks for any input,appreciate it.

Steve

Re: D1SC 8 to 12 rib worth it?
 

A number of guys have cog-ed their D series blowers.

Id say go for it-

Re: D1SC 8 to 12 rib worth it?
 

i'm in the process of doing an F1A cog setup not done yet but there are guys that have used cogs on d series blowers

Re: D1SC 8 to 12 rib worth it?
 

I am doing a 12 rib as well, but on an F1C. Get ahold of Bob at Brutespeed, he should be able to do a lot better on that price. If you ship it US mail it will save on shipping and brokerage fees.

Re: D1SC 8 to 12 rib worth it?
 

I'm not going to chance the cogs right now on the D1. I'll wait until I do the F1. I like the set up that Tony89GTA did in that thread I posted.I Googled the Dayco tensioner he used & looks like it's actually for a diesel so it's pretty heavy duty. They had a video of how its made & they use a flat wire spring which looks way more robust then the coil springs in others.

video here --> http://www.daycoproducts.com/part?ca...number%3D89401

I think if I can get that to work with a 3.4" pulley, looks like you get a little bit more belt wrap as well.

Not sure on where to get the pulleys yet, will have to phone a couple places. It looks like Tony eliminated all but the one lower idler pulley. If that's the case, then just need to find the blower,crank & 1 idler pulley. Some online listings aren't the greatest. Seems like some list 1 or 2 but not all.

Offset 3.4" 12 rib blower here--> http://www.houseofboost.com/store/su....html?page=all

and here--> http://shop.brutespeed.com/ATI-DPxxx...ATI-DPxxxx.htm

I had a site that had the idler's but lost it,so need to find that & a crank pulley.
Probably e-mail Tony89GTA on here & see where he got those...unless he see's this thread & chimes in!

I will continue the search for parts, but have to wait until the engines back to do the tensioner. Hopefully I can figure out how to post pics here, never have but should!

Thanks again for everyone's input!

Steve

Re: D1SC 8 to 12 rib worth it?
 

Go for 12-rib...

I have zero slippage with my setup, work almost to good :)
But then I have made alot of design changes on the setup.

* Spring loaded tensioner, a must when using procharger

* New bracket holder, alot stiffer and wont flex when revving it ( I broke one of the long bolt that holds the stock blower bracket of once)

* New bracket with a adjustable pulley allowing alot more belt wrap on the blower pulley.

* I now also has a bigger crank pulley, only to gain more rpm...

Re: D1SC 8 to 12 rib worth it?
 

I put the spring loaded tensioner on my d1sc (8 rib) and removed the idler pulley and tensioner pulley both. I have no visible belt dust at 10 psi with a 3.85 pulley turning the blower 55000rpm. It works perfectly!

Re: D1SC 8 to 12 rib worth it?
 

Also wondering how the belt alignment is with the tensioner pulley not having any "ears" on the edges like Prochargers idler pulleys have? Could a guy get a 12 rib wide smooth idler from Procharger (with the"ears" on it) & bolt that on the tensioner?
Or the crank & blower pulley good enough to keep it aligned & stay on the tensioner.

Re: D1SC 8 to 12 rib worth it?
 

I used a procharger idler pulley with "ears" on my spring loaded tensioner. Had to make a adapter to make it fit...

/N.

Re: D1SC 8 to 12 rib worth it?
 

I used the spring loaded tensioner and the wide pulley that are listed in the thread you referenced and that's it. If the crank and blower pulley are lined up the belt will stay on. My car is a 6 speed and I've got over 1500 miles on it set up this way. It's never thrown a belt once.

Re: D1SC 8 to 12 rib worth it?
 

I would have thought you wouldn't need them with a rib belt, but checked my 12 rib setup and it does have "ears" on the idler pulley. I haven;t run it yet myself, but it has been proven by others.

Re: D1SC 8 to 12 rib worth it?
 

I'm wondering if you could use the idler pulley from the 8 rib & bolt in on the new tensioner? Not sure if the pulley is wide enough but it is a lot wider then the 8 rib belt. Like you say, if the crank & blower are lined up,should be ok. My 8 rib ran right in the middle of the idler pulleys & stayed there as evidenced by the wear marks.
Thanks again for everyone's input

Re: D1SC 8 to 12 rib worth it?
 

HP52TA, where did you get your pulleys & tensioner? Were they separate or part of the blower kit?

Re: D1SC 8 to 12 rib worth it?
 

They both came with my bracket from Indiana Musclecar, however they are the same pulleys that Procharger sells in their kits.

Procharger lists all there individual parts in the catalog link below, idler pulleys on page 73. The 12 rib pulley is shown as part #DCA003A-012. I didn't see the tensioner though.

https://www.procharger.com/catalogs/...TAIL-small.pdf

One of these guys should be able to set you up with both, however I would confirm they will work with your existing bracket before purchasing. This tensioner has a manual adjustment but is also spring loaded, so would be a nice upgrade if yours is solid adjustment only.

http://www.indianamusclecar.com/install%20pics.html

http://shop.brutespeed.com/ATI-DC003...DC003A-012.htm

Re: D1SC 8 to 12 rib worth it?
 

Tensioner is listed too as Part # DM003I-000.

http://shop.brutespeed.com/ATI-DM003...DM003I-000.htm

Re: D1SC 8 to 12 rib worth it?
 

Steve, if I were you I would give the 8 rib belt a try with the tensioner first. When I was looking around for ideas I seen some corvette guys use a similar dayco spring tensioner and get good results with it. Using the 12 rib setup comes with its own problems, mainly space but since you have a different fan setup it might work ok for you. Another is the cost of the belts, those things are not cheap and really hard to find in our sizes. Having ripped apart a few of those in my experiments it starts to add up lol.

Re: D1SC 8 to 12 rib worth it?
 

Tony, did you end up eliminating the idler pullies all together or did you leave that smaller one down next to the crank pulley? It's there on one of your pics. I found I can get a 64.0" 12 rib belt for $32 here,I work at a GM dealer & that's through one of our suppliers. Not sure if that will be close to the right length until I get the engine back. I'm running the 3.40" pulley & that's the length you said you used,so hope its close. Does the tensioner push down under load to put more tension on it like in the video? Never actually noticed that on any serp belt...then again I never looked while it's under load!
I can get the tensioner off E-bay for, looks like after exchange,shipping etc $150 ish. I can order it through my work from a Dayco dealer for $190 ish. Not sure about E-bay or other "fees" added on by the time it gets here.
Everything's tight on these vehicles, but looking at your pic it looks like they still fit ok.How wide are the 12 rib pullies exactly?
I have to try something,I really don't think 8 ribs are going to work.

Re: D1SC 8 to 12 rib worth it?
 

Sorry for late response, I haven't been on much the last few years.

I had to keep the one down by the crank since I still have the stock fan setup. You might be able to eliminate it all together if you had thinner fans but it might be good to have at least a idler on there to keep the belt from whipping around.

That's a killer deal on that belt and I'm pretty sure it's that length too.

Yes the tensioner will keep a good load on the belt, you probably never really noticed it on like a accessory serpentine setup since it's not really pulling much of a load compared to supercharger.

There might be another dayco part number that might work the same to give you a cheaper price. Think last I looked they were phasing out the part number dayco that I referred to but not totally sure about that.

I'll would have to get back to you on the size of the 12 rib pulleys, don't have the car with me at the moment.

Re: D1SC 8 to 12 rib worth it?
 

You can always run two 6 ribbed belts. The belts are little cheaper that way. My ds1 came with a 64.5" belt and it's about a 1/4 in to short. So I'm going to run 2 gates belts that's 64 5/8 long. Should work well.

Re: D1SC 8 to 12 rib worth it?
 

I've tried the two 6 rib belt idea before with the stock style tensioner setup. I found the belts would stretch a lot more and I ran out of adjustment. They did stay on with the short time I used it, probably would work well with a spring tensioner setup.

Re: D1SC 8 to 12 rib worth it?
 

I noticed that most of y'all have bracket that runs from the top of the supercharger bracket to define the alternator. Mine doesn't have this feature. Do you know if this will be a problem with out the extra support?

Re: D1SC 8 to 12 rib worth it?
 

It does help to have it on there, anything to firm up the main blower plate the better. I did run without it for a few years but I also had a custom bracket holding it on the bottom. You should still be able to buy the bracket separate.

Re: D1SC 8 to 12 rib worth it?
 

My plate does have the holes for the bracket. I will probably just drill it to fit the bracket.

Re: D1SC 8 to 12 rib worth it?
 

if you don't use that small bracket you'll see the bracket flex a lot when you tightening the belt down

Re: D1SC 8 to 12 rib worth it?
 

I'm considering making the move for 8rib to 12 rib. Reason for making the switch is with my current 8 rib set up I can run 13 to 14 pounds of boost without the belt slipping. If I push it harder, say 17 to 18 pounds of boost then I start getting a ton a belt dust (3.70 blower pulley). I'm currently working on getting pricing on the pulleys. I currently have a dayco spring tensioner on my setup, similar to Tony's set up. The pulley that came on the tensioner is currently 1 3/4" wide which wont work for a 12 rib belt that is 2 1/4" wide. Tony do you know what pulley would be needed to support 2 1/4" wide belt? My other issue is space, I've already notched out a section of my aftermarket fan to get everything to fit. Who else has made the 8rib to 12rib switch?

Re: D1SC 8 to 12 rib worth it?
 

I used this one for my tensioner setup, Dayco 89102 46mm wide pulley.

Re: D1SC 8 to 12 rib worth it?
 

Thanks Tony.