What size pulley do you start overspinning the blower?

[DSG03Snake]

I want to predator/pulley soon, I want extra power but my main concern is relability and keeping the car in good shape. I don't want to overspin my blower and end up buying a new one 20-40k miles down the road. At least not until I decide what I want to do with the car, and I'm not really sure I want more then 420-440rwhp (sae obviously) right now.

What size pulley would be the safest? 2.93? 3.10?

Thanks.

 

[04-MystiChrome]

Ya I just read a thread here that a 2.93 overspun the blower
thru 36k miles and it's history. I wonder what the 2.8 & 2.7 are
gonna do in the future. Time will tell-But I still like the 2.93 as
the best compromise of performance & longevity.

 

[ghostrydyr]

What size pulley would be the safest? 2.93? 3.10?

This is easy 3.10.

If 14000 is max blower for eaton (not sure how accurate). If it is the case then with the 2.93 you will have to shift early like 56000k engine rpm to 59000k rpm.

With the 3.10 it would be @ 59000k - 62000k engine rpm.

 

[cobravenom39]

Its not that big of a deal

YOu can buy an eaton from ebay for around $500. I gotta 2.75 and when mine poops, I'll just replace it or buy a kb.

 

[mike79]

Wow really? A 2.93 means you have to replace your blower at around 36k?

 

[hj16]

Originally posted by mike79
Wow really? A 2.93 means you have to replace your blower at around 36k?

Sure:rollseyes

 

[combatstang]

Originally posted by hj16
Sure:rollseyes

exactly sure!!?

if you port the blower that will help big time!!

Marc

 

[DSG03Snake]

Originally posted by ghostrydyr
This is easy 3.10.

If 14000 is max blower for eaton (not sure how accurate). If it is the case then with the 2.93 you will have to shift early like 56000k engine rpm to 59000k rpm.

With the 3.10 it would be @ 59000k - 62000k engine rpm.

Thanks

 

[Chonger]

Re: Its not that big of a deal

Originally posted by cobravenom39
YOu can buy an eaton from ebay for around $500. I gotta 2.75 and when mine poops, I'll just replace it or buy a kb.

Yeah. What he said.

It is obvious a 2.80 will put more wear on the eaton than a 2.93 or 3.10 will. That is the price you pay for the extra HP and TQ right now. That is a choice you have to make. I realize I have cut the lifespan of my eaton by going to the 2.80. In my case I drive about 8K miles a year and plan on going to a KB before the eaton takes a dump on me.

 

[mike79]

Wow, I was gunna do a 2.93, but I guess I'll toss a 3.1 on their instead!

 

[Torch10th]

Who really keeps the Eaton on the car for 40K after putting a pulley on it anyway? I mean realy? If you have the mod bug you are always going to want more. i was in teh same situation, didn't know if I really wanted to pulley down because I don't want to break anything. AFter reviewing my driving habits, how often I drive the car, and what I was wanting, I decided on the 2.8, and the SCT tune. I say go with the 2.93, as said above it's the best compromise between performance, and reliability.

 

[mike79]

Originally posted by Torch10th
Who really keeps the Eaton on the car for 40K after putting a pulley on it anyway? I mean realy?

I would :shrug: Not everyone plans on buying a new blower or tossing on a KB. Some can contain the mod bug!

 

[Nuclrslug]

Why not just rebuild the Eaton? A few bearings etc and you're as good as new. Does everyone go to the dealer to get their spark plugs changed? Things have changed a little but it's still the same old air+gas+spark+compression=power. No DiLithium crystals yet. I guess I just like to tear into my own stuff. I'm not happy unless I've torn it apart, held it in my hands and put it back together again.
I helped a buddy rebuild a Teflon tipped B&M for a BB Chevy a while ago. Simple stuff. Remember, the popular Roots style blower that we now use started off life on 2-stroke Detroit Diesel engines. Some enterprising hot rodders rigged up their own manifolds and drive systems and bolted them to 4 stroke gas engines. Then people like Weiand, BDS etc started casting their own cores. It's old tech, just takes balls to dive into one.

TRIVIA: What's is the first widespread use of N2O? The German Luftwaffe used it in WWII just before the jet age. American pilots in Mustangs (Serindipity?) said the the Germans would roll black smoke and dust them when they hit the laughing gas.

 

[DSG03Snake]

Originally posted by Nuclrslug
Why not just rebuild the Eaton? A few bearings etc and you're as good as new. Does everyone go to the dealer to get their spark plugs changed? Things have changed a little but it's still the same old air+gas+spark+compression=power. No DiLithium crystals yet. I guess I just like to tear into my own stuff. I'm not happy unless I've torn it apart, held it in my hands and put it back together again.

Well personally unless you have done it before it would probably take a while, and I can't really afford downtime until I get a little hybrid or something as a daily driver.

I'll be the first to admit I am NOT good with my hands and working with things, which is why I pay someone to do it, hoping they will do it right and I wont have to second guess my own work.

 

[ygohome]

My eaton is having issues...

http://www.svtperformance.com/forums/showthread.php?s=&threadid=97157

I'm ordering the 03 Cobra Replacement Nose Drive (the snout) for $330. "This nose drive replacement uses new aluminum powder coated castings, input shafts, bearing and seals. Supercharger drive pulley is a 8-rib 2.93"

I'm not sure where to purchase the rotor packs from though incase the nose/snout bearings wasn't the issue.

 

[03gobluecobra]

If in actuality you would be happy with 420-440, why not just consider other ways to get there. I'm at 414(with a broken in engine) with steeda cai and stingers. I could still do a chip, x-pipe, headers, throttle body, or ported eaton, and i would think most of those would put me over 420, or if I did all maybe even over 450. No danger of overspinning the blower. You wouldn't make as much torque as with a pulley, but that might just help keep the tires from spinning so easy.

But like we all know, modding is addictive, especially when a pulley is so cheap and effective.

 

[Nuclrslug]

Originally posted by DSG03Snake
Well personally unless you have done it before it would probably take a while, and I can't really afford downtime until I get a little hybrid or something as a daily driver.

I'll be the first to admit I am NOT good with my hands and working with things, which is why I pay someone to do it, hoping they will do it right and I wont have to second guess my own work.

I understand and I'm not trying to belittle anyone but here's my situation: I'm poor, good with my hands (don't ask my girlfriend to verify) and want to go as fast as possible with "X" dollars. I'd rather do it myself because I know I care more about my stuff than some monkey in any given performance shop would. More power to you I just get off on doing it myself.
My definition of "Americana" is building a small block Chevy including boring (balancing and hanging rods is the only shop work performed), shipping it down to Florida, installing it, driving it back to Michigan for final tune and driving it 2,500 miles to California. It's a sense of accomplishment that I enjoy. I lost interest in my Olds because it's "done". I love going fast but chasing it is at least half the fun.
My definition of fear: Tearing a Holley 850 double pumper apart on top of said SB Chevy along a highway in Oklahoma with semi's doing 75mph 2 feet from your ass because I blew a power valve.
My Definition of frustration: Trying to fing a power valve for said holley in Oklahoma (found one in New Mexico). Broken off tooth picks plugging fuel ports got me there.
YeeHaw! The good ole' days.:rockon: :rockon: :rockon: :rockon: :rockon: :rockon: :rockon: :rockon: :rockon: :rockon: :rockon:

 

[Black306]

Originally posted by DSG03Snake
I want to predator/pulley soon, I want extra power but my main concern is relability and keeping the car in good shape. I don't want to overspin my blower and end up buying a new one 20-40k miles down the road. At least not until I decide what I want to do with the car, and I'm not really sure I want more then 420-440rwhp (sae obviously) right now.

What size pulley would be the safest? 2.93? 3.10?

Thanks.

Any pulley will "overspin" the blower. If the "limit" is 14,000

(7.625 (stock lower) / 3.4 (stock HD upper)) * 6,500 engine RPM = 14,577 blower RPM

Personally, if I go with a pulley, it'll be a 3.2. I'm semi-concerned about over spinning the blower too. However, since I only shift at just past 6,000RPM, that'll be only ~14,750 blower RPM.

 

[ghostrydyr]

03gobluecobra

I agree with you. Also 420rwhp is a lot, as a matter of fact good enough to beat a lot of cars on the road. A good pulley and it doesn't even need a tune xpl: for poor Cali folks 91 octane) is the 3.4 pulley and you can get 420 rwhp and 400-405 rwtq.

With the 3.4 you will not over spin the blower till around 66000 engine rpm. Assuming 14000rpm is overspinning the stock eaton.

 

[mike79]

I thought the stock blower pulley was a 3.6?