Changing the pulley- pics & notes.

03SoCalCobra

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(Note- this is written for people don't have a lot of experience or who are not very comfortable with the proceedure.)

Pictures will be in the second post after this!

The only tools you need for the pulley swap are the pulley puller (ASP or PulleyBoys); the new pulley, a little anti-sieze or oil, two wrenches, a new belt and a cold beer (that'll come in handy shortly). Total time on your first try will be 30-45 minutes; after that you can probably do it in 15-20 max.

I used an ASP puller; the overall operation is the same with both PB and ASP although the size of the wrenchs will differ.

Step 1. Disconnect the battery cable (either one). Assuming you already have the belt guard removed by taking off the 3 nuts, remove the pilot screw from the middle of the pulley, it comes of easily.

Step 2. Remove the blower belt. The idler tension arm is on the left as you're facing the engine. At then end of the arm where the pulley is, you'll see a square hole. Pop your 1/2" socket wrench in and push down- this will release the tension and allow you to slip the belt off (it's easier to slip off one of the smooth pullies first to get more slack to take it off the blower pulley). Leave the rest of the belt on.

Step 3. Measure the distance between the back of the stock pulley and the blower housing. I used a piece of cardboard and a marker. Lay the cardboard across the top of the pulley with the back of the cardboard resting against the front of the blower and mark where the pulley edges are. This will help line it up during re-install of the new pulley. (My instructions said the new pulley would be flush with the shaft which wasn't exactly correct).

Step 4. Slip the large U-shaped piece behind the blower pulley and assemble the puller by adding the two (ASP) or three (PB) guide bolts and the main center bolt that does all the work. Once assembled, the whole thing moves as one unit- the pilot screws just align the back plate with the front plate, you don't tighten them very much.

Step 5. Thread the main, large bolt into the now-vacant pilot screw hole in the end of the blower shaft (you'll have a large bolt that tapers at the end into a smaller screw which fits the pilot hole). I went finger-tight then backed it out a 1/4 turn for some wiggle room. The big bolt must not turn during install/removal.

Step 6. At this point, you should have a large nut and washer between the front bar (ASP) or plate (PB). Put oil or anti-sieze on the threads and both sides of the washer. The job requires a lot of force and you don't want the added overhead of friction between the nut and washer.

Step 7. Secure the big bolt so it doesn't move. I used a 15/16ths socket and breaker bar (ASP), just let it rest on top of something solid. I also added a small strip of electrical tap on top of the socket so i could make sure the nut wasn't rotating.

Note- I also put a piece of electrical tape on top of the blower snout right behind the pulley so i could gauge progress as the pulley was comming off. Not required, but it give a little piece of mind that all that effort is actually moving something.

Step 8. Using another wrench, crank on the nut thats between the pulley and the front puller plate. This will a) press on the blower shaft and b) apply pressure to the front plate which will pull on the guide bolts connected to the back plate behind the pulley and viola...

Note- I used a 12" crescent wrench and braced myself against the quarter panel (watch out for buttons on your pants) and pulled... HARD... You'll get to a point where you think you'll break something (this is where the beer comes in handy). You need to psych yourself up and just keep cranking. My 1" thick piece of aluminum bar on the ASP setup actually started bending before the pulley moved. IMHO, getting over the mental part is harder than the physical part.

Step 9. This is where that electrical tape on the blower snout comes in handy. You'll start to see a widening gap as the pulley comes off and the effort will decrease greatly the more the pulley slides off.

Step 10. Reinstalling the new pulley is the same operation in reverse- easy in the beginning, very hard at the end. You only use the front puller plate/bar with the nut on the other side. Now the big bolt (while still not moving!) is pulling on the blower shaft rather than pressing on it.

Step 11. After the new pulley is on (using line of site, your cardboard or ruler to make sure it's lined up with the other pulleys), make note of how the belt is routed then slip it off the other pulleys and remove completely (twist it sideways to get it off the idle tensioner, it's a tight fit behind the arm).

Step 12. Install the new belt. This is relatively easy since you have smooth pulleys and grooved pulleys and the smooth parts are for the back of the belt and grooved for the inside part of the belt.

That's it! Put the battery cable back on, fire it up and make sure the belt is working and in alignment. I don't have my chip yet (hello? JDM?) so I drove it fairly easy for the first few days to let the freshly-reset engine computer to get cozy with the new airflow.

Forget gears with this mod, IMHO. First is over really quick and the pull in 2-6 is nothing short of amazing :eek: :eek: :eek: I have as much pull in 6th as i did in 5th before the mod.
 

03SoCalCobra

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And the coorispoinding pictures, enjoy!

pulley1.jpg


Note the bent bar- Pulley Boys steel plate shouldn't do this

pulley2.jpg


pulley3.jpg


pulley4.jpg


pulley5.jpg


Gauge actually goes higher, i just wanted to show the effect at low rpm.

pulley6.jpg
 

Mac03Cobra

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:thumbsup:

Well done....

How much difference do you think the chip will make?, and is
it really needed?

Any concerns with overspinning the rotors?

Again, nice job.....

Mac03Cobra..
 

f4sfed

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I ended up putting on the same pulley (2.93). I wasn't going to at first, but I was readin' where there are Lighting guys/gals running their blowers up to 17psi! And they don't have iron blocks with Manley forged connecting rods (at least I don't THINK they do). :lol: So I figured I'd be safe with 12psi. As far as the blower rpm, do a search...I've read threads on blower speed, and it calmed my nerves (obviously enough to do it). :)
 

Z06_2002

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03SoCalCobra,

Awesome instructions and pictures, thank you. I cannot seem to make the pulleyboys puller line up correctly with the pulley stem. I am running into the coolant lines and will not allow the back to drop down far enough. Any ideas?
 

03SoCalCobra

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Originally posted by Z06_2002
03SoCalCobra,

Awesome instructions and pictures, thank you. I cannot seem to make the pulleyboys puller line up correctly with the pulley stem. I am running into the coolant lines and will not allow the back to drop down far enough. Any ideas?

It appears all the pullers were made for the Lightning which appearently has more clearence. That's exactly the same problem i had the the ASP puller. The bolt holes on the PB puller look pretty close to the bottom. I'm not sure you have enough space to cut it without getting too close to the holes, but that's just what i see off the pics on their site so you may be in better shape (i'd loan you mine if you were near So.Cal).

You'll have to hack some off the bottom of the inverted U so the puller settles behind the pulley and allows all 3 guide bolts to line up when the large bolt is screwed into the blower shaft. I lucked out and had a friend with a milling machine do aluminum ASP part, but any machine shop should be able to do it in 5 minutes for a very minimal charge.
 

FlashSVT

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You'll have to hack some off the bottom of the inverted U so the puller settles behind the pulley and allows all 3 guide bolts to line up when the large bolt is screwed into the blower shaft. I lucked out and had a friend with a milling machine do aluminum ASP part, but any machine shop should be able to do it in 5 minutes for a very minimal charge.
I took 1/2 an inch off both sides of the "U" on my ASP puller and it worked fine.
 

totaled

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03SoCalCobra,

Great instructions and pictures :thumbsup:

Flash, I was hoping after reading your post the other day the Pulley Boy puller would be the perfect puller sorry to hear it didn't work out.
 

FlashSVT

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Flash, I was hoping after reading your post the other day the Pulley Boy puller would be the perfect puller sorry to hear it didn't work out.
Me too. The ASP puller I had from my Lightning worked, but i needed to do a lilttle trimming. It also bowed like crazy. I'm having a shop make me a "bar" in steel for the next time I use it.

I heard that Rick @ Amazon Racing is coming out with a steel puller as well that will work fine with the Cobra.

See ya . . .
 

Z06_2002

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Hey you guys, just got finished with the pulley swap and I was able to use the pulleyboys tool. Simple mod, dremel tool and taper the two rear edges of the plate by about 1/8 of an inch. New pulley is on, going to do the chip right now, and if I feel real ambitious I will do the off road x pipe tonight also. Hey Brian at pulleyboys.com was extremely helpful and fast. Totally cool guy.

03SoCalCobra, couldn't have done it without your excellent instructions! Thank you kindly.

:beer:
 

n0xlf

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I'm sure this has been posted a million times on here, but can someone throw the part number for the new belt on here? Excellent post that I plan on printing and would like to throw that on here somewhere...

And where's the cheapest place to get the 2.93 pulley?
 

ronreid03

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Great Write up! Thanks a bunch. This will make a lot of folks nerves settle down when we change our pulleys!

Can we get this copied to the "how to" section so it doesn't get lost over time?

Ron Reid
03 Yellow Convertible
 

03SoCalCobra

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Originally posted by Z06_2002
Hey you guys, just got finished with the pulley swap and I was able to use the pulleyboys tool. Simple mod, dremel tool and taper the two rear edges of the plate by about 1/8 of an inch. New pulley is on, going to do the chip right now, and if I feel real ambitious I will do the off road x pipe tonight also. Hey Brian at pulleyboys.com was extremely helpful and fast. Totally cool guy.

03SoCalCobra, couldn't have done it without your excellent instructions! Thank you kindly.
:beer:


Hey Z, how did all the mods go??
 

FlashSVT

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Simple mod, dremel tool and taper the two rear edges of the plate by about 1/8 of an inch. New pulley is on, going to do the chip right now, and if I feel real ambitious I will do the off road x pipe tonight also. Hey Brian at pulleyboys.com was extremely helpful and fast. Totally cool guy.
Cool, maybe his next batch will come "Cobra-Ready" :)
 

vcmoore

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Originally posted by n0xlf
I'm sure this has been posted a million times on here, but can someone throw the part number for the new belt on here?

Yes could someone please post the part#. I too am running the 2.93 pulley, but I've been using the factory belt...
 
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n0xlf

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I found it - For the 2.93, the Goodyear Gatorback 4080745... $26 at Autozone if you can get one..All of the Autozones around me say that they can't even order them because their supplier shows out of stock..

Where did you get your 2.93 pulley from? Seems like press fit ones are hard to find..UPR has one for $119 I think, but they seem to be about the only place..
 

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