3.2 front pulley on Maggie

[11syn3rgy]

Hey guys,

I'm well aware the "best" way for me to increase boost (without belt slip) is to OD my rear set up, but if I have the JRE Super Tensioner, is there any chance that my set up will hold a 3.2 front pulley? I hear other blower set ups run smaller diameter pulleys but maybe they have a different design that helps with belt wrap? The reason I am asking is I am currently tapped out at 91/93 octane (9.5 psi). I have a separate "race tune" set at 97 octane and it would be easy enough to change the front pulley if I wanted to. Not so easy to change the rear set up before each race. Just thought I'd throw it out there in case I'm not the only one running into this. I'm trying to see if there is another option other than installing a new fuel pump. See the signature line for my current mods.

Thanks!

[2SSCAMARO]

Overdrive the rear for sure. Preferably cog drive and you will never get any slip. You will never have to mess with the back again. Just change your front pulleys as necessary. I have 3.4, 3.6, 3.8, and 4.0 front pulleys. You'll also need to keep on hand at least two different front belt sizes to properly fit the various size pulleys. A 3.2 on the front is just asking for belt slip even with a super tensioner.

[11syn3rgy]

Originally Posted by 2SSCAMARO

Overdrive the rear for sure. Preferably cog drive and you will never get any slip. You will never have to mess with the back again. Just change your front pulleys as necessary. I have 3.4, 3.6, 3.8, and 4.0 front pulleys. You'll also need to keep on hand at least two different front belt sizes to properly fit the various size pulleys. A 3.2 on the front is just asking for belt slip even with a super tensioner.

Yeah, I'm sure you're right. I was just curious if anyone was running the 3.2 at the track only. I wouldn't try and running it all of the time. It was just a thought. Thanks!

[11syn3rgy]

Does the rear "cog" set up produce more whine? I kinda like how stealthy mine is right now

[swiftkart]

It does at first, but after the cog belt breaks in it gets quieter, at least mine did.

[2SSCAMARO]

If some one tells you that a 3.2 does not slip, I would like to see a quarter mile log after the belt has been at the track a couple of times. The rears cog belt does "whine" more than the micro v belts. A cog belt that is over-tensioned whines louder than a properly tensioned belt and an under-tensioned belt produces little to no whine. This is typically what they sound like when properly tensioned.

[11syn3rgy]

Originally Posted by 2SSCAMARO

If some one tells you that a 3.2 does not slip, I would like to see a quarter mile log after the belt has been at the track a couple of times. The rears cog belt does "whine" more than the micro v belts. A cog belt that is over-tensioned whines louder than a properly tensioned belt and an under-tensioned belt produces little to no whine. This is typically what they sound like when properly tensioned.

Ok, thanks man. Great video. Car sounds bad ass. Unfortunately, that's still more whine than I'd like. I'll probably just stay with my current set up and look to add E85. I appreciate the input.

[2SSCAMARO]

It's your call but my opinion is that the cost of the E85 conversion outweighs the increase in performance gained. You can run the 3.2 pulley, still gain some boost and after X amount of passes expect some slippage and replace the belt as needed for track passes. Use the worn belt for the street....so what if it slips a little during WOT. How many seconds can you hold WOT on the street anyway! As far as fuel goes, I would be keeping a close eye on the fuel pressure during WOT if you try the 3.2. There comes a point when just one more pulley down becomes too much for your current set up to handle safely.
Also, you can still overdrive the rear with non-cog 10 rib pulleys if you don't want the whine of the cogs.

[11syn3rgy]

Originally Posted by 2SSCAMARO

It's your call but my opinion is that the cost of the E85 conversion outweighs the increase in performance gained. You can run the 3.2 pulley, still gain some boost and after X amount of passes expect some slippage and replace the belt as needed for track passes. Use the worn belt for the street....so what if it slips a little during WOT. How many seconds can you hold WOT on the street anyway! As far as fuel goes, I would be keeping a close eye on the fuel pressure during WOT if you try the 3.2. There comes a point when just one more pulley down becomes too much for your current set up to handle safely.
Also, you can still overdrive the rear with non-cog 10 rib pulleys if you don't want the whine of the cogs.

Yeah, all good points. I'll ask my tuner about his opinion on running the 3.2 front pulley for "track only" events. I have a feeling what he's going to say. If I run the OD rear pulleys and the 3.8 on the front, what will that give me for boost? My current set up (3.4 front pulley) produces 9.5 psi.

[pdiddy]

Od rear with 3.8 front on mine is 9.5-10psi depending on the day

[old motorhead]

With overdrive ribbed pulleys and a 3.8" front pulley, you're looking at the equivalent of a 3.27" front with 1:1 rears. The overdrive rear pulleys are 3.49" on the jackshaft and 3.0 on the back of the blower. The math is 3.8/3.49X3.0=3.27. A 3.27" pulley (if they made one) vs your 3.4 should yield a little more than an extra # of boost.

Cogged rears are a little different in that you have to count the cogs to get the o/d ratio. I used to remember the cog numbers, but have lost too many brain cells since then

[11syn3rgy]

Originally Posted by old motorhead

With overdrive ribbed pulleys and a 3.8" front pulley, you're looking at the equivalent of a 3.27" front with 1:1 rears. The overdrive rear pulleys are 3.49" on the jackshaft and 3.0 on the back of the blower. The math is 3.8/3.49X3.0=3.27. A 3.27" pulley (if they made one) vs your 3.4 should yield a little more than an extra # of boost.

Cogged rears are a little different in that you have to count the cogs to get the o/d ratio. I used to remember the cog numbers, but have lost too many brain cells since then

This is great information. Thanks man!

[2012LS3VERT]

Originally Posted by 11syn3rgy

Hey guys,

I'm well aware the "best" way for me to increase boost (without belt slip) is to OD my rear set up, but if I have the JRE Super Tensioner, is there any chance that my set up will hold a 3.2 front pulley? I hear other blower set ups run smaller diameter pulleys but maybe they have a different design that helps with belt wrap? The reason I am asking is I am currently tapped out at 91/93 octane (9.5 psi). I have a separate "race tune" set at 97 octane and it would be easy enough to change the front pulley if I wanted to. Not so easy to change the rear set up before each race. Just thought I'd throw it out there in case I'm not the only one running into this. I'm trying to see if there is another option other than installing a new fuel pump. See the signature line for my current mods.

Thanks!

To answer the question about the other blowers with smaller pullies, yes, just about all the other designs have better belt wrap than the jackshaft Maggie. However, you will get some slip, I actually had a little with my 3.4 pulley, before I went OD cogs. With the tensioner, you should be a little better off. I ended up switching to rear cogs. Your option there is to go with rear cogs and a 3.8 (about 9.5-10 psi) for the street and a 3.6 at the track, then you can still easily change them.

[old motorhead]

Also, get you a high quality belt. A Gatorback, Gates green, or Gates blue. The OEM type belts will usually hold a little while and then get sloppy after a few thousand miles and a few hard pulls. I'm a fan of the Gatorback belts. They hold well and don't stretch as much under load as the stock type belts. Use the smallest one you can pry on there