Pulley 101 .......info for dummies like me

[PQ]

So, recently I discovered kinda what I suspected for a while........

My 2.8" pulley on the front of my Maggie ideally should be creating around 11-12 pounds of boost and not 8.

I have had my TVS2300 Magnacharger on my car for a long time now. LOVE it. But it never sat well with me that I am running such a small pulley to only get an 8-8.5 psi average through a dyno pull.

Now to be accurate, I am running a 3.2 inch pulley on it with my daily driving. Keeps me safe as far as boost goes and the 2.8 is not needed for the street anyway imo. I can throw the 2.8 on in 5 minutes if I want to go to the strip or have some fun.

But the 2.8" pulley produced an average of 8 pounds on the dyno and the 3.2 produced an average of 6 pounds. (see bottom two dyno graphs) Before my cam I had dynoed the car with a 3.6" pulley to a 7-8 pound average. I know I lose some adding a cam and I still have to get my cam specs but it's a mild cam and I can't see losing THAT much boost.

So now I'm going to be buying an OD cog drive for the back and getting a boost gauge so I can see what size pulley will net me an 8 pound average.

Now my ultimate question that drove me to create this thread is what the hell is the point of 6 rib 3.2 down to 2.8 pulleys if they can't pull solid and they slip so badly?

I mean that's some seriously shitty belt slippage to lose so much boost. I just don't feel comfortable with my car tuned for a level based on a slipping belt.

What if the belt decides one sticky day that it wants to grab for a minute? BOOM............... right?

Or is that not possible?

I may need a fuel rail or cut my existing fuel rail but I am going to get a rear OD Cog drive so I can take care of this but WTF? Why the hell are they selling these pulleys if they don't work?

[Ray@RDS]

Its not always about what you are spinning on the outside, but how well those rotors are spinning on the inside. It has been proven that there is resistance inside, Just not noticeable at the 550 rwhp mark.you end up finding that resistance at the outer most noticeable point pullies and belts. give that blower a lift and port match those intake runners then hold on!

[Brolik10]

You will most definitely need the fuel rail indentation with the OD cog!

[Brolik10]

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[Supermaro585HP]

Ok I hope someone can help me. I have a Edelbrock supercharger and want to put a smaller pulley on it. I have a auto tranny. I was told I should put a ZL1 fuel pump on it. What is the smallest pulley I should get and do I need a fuel pump? I use my Camaro as a summer daily driver. Like I said I have a Edelbrock supercharger CAI long tube headers and cat back exhaust. Please help me because I want to get this done as soon as possible because my buddys Mustang is getting some upgrades and I need to be ready.. LOL Thanks If you could PM me that would be great

[Supercharged SS]

Originally Posted by Brolik10

You will most definitely need the fuel rail indentation with the OD cog!

PQ, I think Ted has machined rails in stock and then you can return your core.

If you ever find out why they make such small pulleys that don't work let me know. I'm curious myself!

[Supercharged SS]

Originally Posted by Supermaro585HP

Ok I hope someone can help me. I have a Edelbrock supercharger and want to put a smaller pulley on it. I have a auto tranny. I was told I should put a ZL1 fuel pump on it. What is the smallest pulley I should get and do I need a fuel pump? I use my Camaro as a summer daily driver. Like I said I have a Edelbrock supercharger CAI long tube headers and cat back exhaust. Please help me because I want to get this done as soon as possible because my buddys Mustang is getting some upgrades and I need to be ready.. LOL Thanks If you could PM me that would be great

I'm not sure how the pulley vs boost works with an E force but I wouldn't get one that makes more than PSI. The ZL1 fuel pump is a great idea and there is also a fuel rail upgrade for that blower that Ted has that is something you will need. Ted has all tha stuff on the shelf and can give you concrete info.

[Supermaro585HP]

Ok you said more than PSI. What do you mean. This shit is all new to me. Thanks for the help man.

[Supercharged SS]

Originally Posted by Supermaro585HP

Ok you said more than PSI. What do you mean. This shit is all new to me. Thanks for the help man.

Psi just means boost. So 10 psi is 10 pounds of boost.

[Turbo99]

Originally Posted by PQ

So, recently I discovered kinda what I suspected for a while........

My 2.8" pulley on the front of my Maggie ideally should be creating around 11-12 pounds of boost and not 8.

I have had my TVS2300 Magnacharger on my car for a long time now. LOVE it. But it never sat well with me that I am running such a small pulley to only get an 8-8.5 psi average through a dyno pull.

Now to be accurate, I am running a 3.2 inch pulley on it with my daily driving. Keeps me safe as far as boost goes and the 2.8 is not needed for the street anyway imo. I can throw the 2.8 on in 5 minutes if I want to go to the strip or have some fun.

But the 2.8" pulley produced an average of 8 pounds on the dyno and the 3.2 produced an average of 6 pounds. (see bottom two dyno graphs) Before my cam I had dynoed the car with a 3.6" pulley to a 7-8 pound average. I know I lose some adding a cam and I still have to get my cam specs but it's a mild cam and I can't see losing THAT much boost.

So now I'm going to be buying an OD cog drive for the back and getting a boost gauge so I can see what size pulley will net me an 8 pound average.

Now my ultimate question that drove me to create this thread is what the hell is the point of 6 rib 3.2 down to 2.8 pulleys if they can't pull solid and they slip so badly?

I mean that's some seriously shitty belt slippage to lose so much boost. I just don't feel comfortable with my car tuned for a level based on a slipping belt.

What if the belt decides one sticky day that it wants to grab for a minute? BOOM............... right?

Or is that not possible?

I may need a fuel rail or cut my existing fuel rail but I am going to get a rear OD Cog drive so I can take care of this but WTF? Why the hell are they selling these pulleys if they don't work?

PQ as we told you in the other thread, you need a Super tensioner to go below a 3.4 pulley now the 2.8....not sure why they made that I would say a 3.0 will be the smallest you will ever get to hold.

[2010SSRSM6]

With the 2.8" pulley you should be way the hell up there in boost. You have got to be getting serious belt slippage or your cam is not allowing it to build boost. How much belt dust are you getting?

Have you upgraded your pulley system to an 8 rib or are you still running the 6 rib system? There is an IW 8 rib setup in the members FI for sale section that should help you out.

[Supercharged SS]

Originally Posted by 2010SSRSM6

With the 2.8" pulley you should be way the hell up there in boost. You have got to be getting serious belt slippage or your cam is not allowing it to build boost. How much belt dust are you getting?

Have you upgraded your pulley system to an 8 rib or are you still running the 6 rib system? There is an IW 8 rib setup in the members FI for sale section that should help you out.

I just told FLOMO to pm PQ about it!!!!!

[2010SSRSM6]

Originally Posted by Supercharged SS

I just told FLOMO to pm PQ about it!!!!!

Great minds think alike.

[The Stig]

Ted posted this awhile back. I know it's not really related, but it does answer your question about belt slippage and why tensioners are so important.