Cogged Belts and/or suitable ribbed

[stevieturbo]

I bought a kit of parts, to fit a V7 YSi to my LS1 engine, using 50mm cogged drive. Crank is a large 86T, SC 34T
Id like to have options of using around 9-14psi without slippage issues, which I read so much about. Possibly more boost at a much later date.

As things stand, the belt supplied is too short. Its a Gates 50mm, 1600mm long.
I contacted Gates here in the UK ( its stamped Made in UK ), and they say the longest belt of that type is 1610mm.
I need a belt about 1635-1640mm long to get the correct belt path.

Does anyone know of a supplier of a longer belt that will work ??

Markings on belt are..

1600 8M 50 7 483DS, Gates, Made in UK

If another belt isnt available, is there a 8/10 or even a 12 rib setup available ??

Im using a powerbond crank pulley, which has 6 x 3/8" UNF fixings for additonal pulleys, onto which my cogged pulley bolts via a spacer
http://gallery112848.fotopic.net/c332887.html

current configuration....insulating tape replaces SC pulley, as it wont fit on with that belt.
http://gallery112848.fotopic.net/p10596488.html

If the belt is fitted without tensioner, it is actually tight already and very very difficult to get on. It fouls the water pump pulley coming off the crank, and would also fould PAS pump nose.

Obviously the people who supplied these parts should resolve this problem, but Id like to know what options are available. As can be seen, I have room for a 50mm wide belt, so I think any 8-10-12 rib would do. The wider the better.

Thanks, Stevie
<!-- / message --><!-- sig -->__________________

[BLOWNBY]

If you are only looking for 14 lbs max then all you'll need is an 8 rib setup with an 8" crank and like a 3.13 SC pulley. You should have very minimal slip if any with this setup. If you have the room then go with a 10 rib setup.

12 rib and 50mm cog is too much for this. 10 rib is almost to much. Plus there is no need to deal with the potential headaches with cogs for that little boost. Plus it is easier to find the exact length belt you need in 8 & 10 rib than 12 or cogs. A lot more choices available.

[stevieturbo]

I really dont get this.

I read so many posts about slippage issues, and people adding various tensioners etc to get more belt wrap to prevent slippage, on both 6 and 8 rib setups, with cars pushing even 6-700rwhp using different blowers. Ive heard of some with slippagge at much lower power outputs..

Then searching old threads elsewhere, people where saying why doesnt anyone make a cogged setup for an LS1 to prevent this, and they would love to try one ?? These threads ended with people saying they had ordered some from, but ended there. No idea if they ever got up and running.

What exactly are the problems with a cogged setup ??

Why would you say a 10 rib or 12 rib is too much ? Surely over-engineering in this area will extend belt life, reduce slippage, and generally make for better service ??

I have room for a 50mm Cogged, so would have plenty of room for a 10rib Poly-V asssuming someone makes a pulley to bolt to my crank pulley

14psi or so will no doubt give me plenty of power, but I do want a setup that can easily handle more if I decide to push further, without worrying about slippage, or belt throwing or breaking etc.

[BLOWNBY]

LAst year I made 670 rwhp with 20 psi. I ran a 8 rib 8" and 2.7 ". I had some slippage issues. The 2.7 is a small pulley to get good bite with. If your looking for 14 psi, then a 3.13 should put you there. This is much bigger than a 2.7. So you'd have less slippage issues than I had due to the larger pulley and less drag from the blower at 14 psi. So you'd have very minimal slippage issues. Thus I'd say the 10 rib at 8" an 3.13 would work perfectly.

If you go to a 12 rib setup it is hard to find makers of a 12 rib belt plus finding the exact size you need. This is true with cogged setups. Plus with cogs a lot of people seem to throw or chew teeth of the belt. (not always, but the potential threat is there).

In the 10 rib you'll have various manufactures making these belt in virtually evry 1/2 increment needed.
http://www.superchargerhelp.com/showthread.php?t=6834

This year I plan on making 22-24psi on a 10 rib setup. I will be having ASP make me a custom 8.5" crank pulley so I can run a larger 2.95-3.10 SC pulley vs the 2.7. I expect to have virtually no slippage issues. I too have been kicking the cog idea around all winter and last year, but have opted to go the 10 rib route. I want to stay away from cogs if possible. I believe this setup will solve all my problems.

[stevieturbo]

I did email ASP about options too...

Can they make any pulley to spec then ?? ie, could they make me a 10rib pulley to bolt to my crank pulley adaptor, that the cogged pulley currently bolts to ?

Diameter isnt a problem, as the cogged crank pulley I have is almost 9", so this would help even more allowing larger blower pulleys for more belt wrap.

What sort of price would a custom pulley be ??
Heres a pic of the crank pulley setup. Powerbond crank pulley. Spacer, then the 86TCogged pulley. Secures with 6 x 3/8" UNF bolts.
I would need only the cogged pulley replacing
http://gallery112848.fotopic.net/p8886909.html

[BLOWNBY]

I would imagine they could make what you need. You'd have to check with them for sure. They quoted me like $350 for the 8.5" or so size in a 10 rib. They should be able to make what you need. 8.5, 8.6, 8.7 etc.. When you find out what they can do, I can help you determine pulley sizes. Maybee you should go like 10 rib 8.6" & 3.33" Definitly no slip and ~14 psi. I figure about $500-$525 for a custom crank and SC pulley, idler and belt. Cogs would have been even more. Sounds like a lot but just for a regular 10 rib setup was like $300. So an extar $200 and not having to worry about slippage and always replacing belts is worth it.

[stevieturbo]

I'll wait and see what CAPA say, as if they cant solve my problem, I want a refund on the parts they supplied me, then I can source elsewhere.

This was the one part I expected to be easy, as I ordered a complete kit, so as to make it hassle free.
Typical!!!!!

[BLOWNBY]

The lovely world of aftermarket!!:laugh:

[stevieturbo]

The plot thickens......

Not sure if I should or shouldnt do this, but here is the most recent email response I have received about this matter.
Now, I think you have an idea of my problem. Id like a second opinion on this reply, as I find it difficult to believe.

Quote
"This pulley kit on a std engine will make about 15psi boost.. What you should have got is a smaller crank pulley and smaller s/charger pulley.. We dont really recommend fitting a V-7ysi to a near std engine, be very careful that you dont cavitate the supercharger unit and destroy it.. I suggest our smaller gilmer pulley (crank 78T and 30T s/c) will be what you need.."

Now, IMO this will give even more boost. It will leave the belt slack, by approx 12 teeth. 12 x 8mm = 96mm. Thats nearly 4 inches. I wouldnt have anywhere for that 4" to go with a similar pulley arrangement. It also doesnt leave much scope for more boost, as 28T is the next smallest pulley, which is a large jump.

Opinions ???

[BLOWNBY]

This furthur points to why the 10 rib will be easier to get going and maintain. Hard to find proper cogs belts as you change your setup. Here is a link about cogs on a YSi. You maybe able to get some more insight from this guy as he has run cogs on a YSi.

http://www.superchargerhelp.com/show...4&page=1&pp=15

He talks of the advantages(more boost sooner) and disadvantages (throwing and tearing teeth off), as opposed to the 8 rib setup. The 10 will help to bring on boost sooner as well. Plus he has some boost #'s 73/30 tooth made him 18 psi. (54,901 rpm's Blower speed) your 86 & 34 tooth would put it at (54,104 rpm's) So it should make similiar boost to his setup at 16-17 psi. The 78 & 30 would be like (55,614 rpm's) That would be like 1 more pounds of boost. Again these boost # are not exact as estimates as there are so many variable to this.

Plus he was saying with the bigger crank pulley on cogs you run into more issues as opposed to a smaller one. And you definitly have a big one!

I would go with the 10 rib setup as before. Especially if the car will see more street than track. My opinion. Again I have looked cogs hard and long and will be opting for the 10 rib setup.

[stevieturbo]

Sod it...ASP have given me a good price on cutting my 86T for a ribbed setup.

I'll juts get that done, It will save lots of hassle in the long run. Going to get it grooved all the way across, so I have the option of 12rib later too, and should make for more alignment options.

Thanks for the advice. I'll post an update when I get the pulleys back from ASP.

A Damn sight more helpful than CAPA, thats for sure !!!!!!!!

[BLOWNBY]

Thanks for the advice. I'll post an update when I get the pulleys back from ASP.

A Damn sight more helpful than CAPA, thats for sure !!!!!!!!

Good to hear that we were able to help. What size pullies are you going to get?

[stevieturbo]

Whatever they make me !!!!

Until they machine the crankshaft, dont know what its final size will be. Then I'll get some blower pulleys to suit what i want.
Will aim for 7-8psi for use with the std engine, and 12-13psi for when I put together the low compression engine, and take things from there.

[stevieturbo]

Measured things tonight. Crank pulley will probably end up closer to 8" after machining, possbily slightly smaller.
I'll get it posted off to them tomorrow, and hopefully they can do a quick turn-around and I get it all put together.
At least thats one item that looks like being sorted out.

[331stroker]

[QUOTE=BLOWNBY]If you are only looking for 14 lbs max then all you'll need is an 8 rib setup with an 8" crank and like a 3.13 SC pulley. You should have very minimal slip if any with this setup. If you have the room then go with a 10 rib setup.

Hey, I have a question about the 3.33 SC pulley with the 8" crank.. Will I have clearence issues with the water pump ?

Does anyone know or have done this before ???

Appreciate it !