I just got off the phone with a very nice and knowledgeable ATI Tech.

Rather than rehash the past, long story short is I got screwed by the original teeth count I received of 38 26, I have never been able to get anyone to answer that until today.

According to them everyone gets a 38 27
https://my350z.com/forum/showthread....0&pagenumber=1

"Unless specifically requested" well my installer gave me a car with 4 pulleys, the wrong one on there and a blown engine. Even ATI claims they would have known better.

It should have been a 38 27 it wasn't and never was it was one tooth less at 200asl!

Anyways that was settled in court and a non issue but this is why it is important.


"You cannot go above 65 teeth to keep the system in balance! I didn’t know this and I have never seen it mentioned anywhere!

This is why my friggen belt is too tight, it's why my boost is too high and why I was lean and that is why I was making all the does your pulley wobble posts! It wasn’t balanced!

The tech was very nice, he wants to make my kit right and helped me and taught me some cool tricks too for getting the pulleys off w/o removing the bracket (both of them.)

My car is tuned for 9 lbs by Technosquare. I went down there with a 41 and 26 and made 11 PSI! 67 teeth!

Tadishi being the Ultimate Tuner that he is kept the A/F and timing good (others I know would have grenade’d it.) No one here will ever convince me Tadishi doesn’t know this car!

When I got home I switched the 26 to a 27 to lower the boost, now it is 10 pounds and I need 9 right?

Well do the new math.

41 + 27 = 68 teeth BAD... To lower the boost I raised the teeth count past 65!

The belt will eventually break; it's out of balance and needs to be fixed.

I explained to the tech that I was flashed for 9 lbs and was staying that way no matter what and this is his recommendation.

Run the 38 (Ughh here we go again with the labor) where the 41 is with the 26 I got with my second order (also placed by the installer not me and probably ran too!) BOOM!

38+26 and I should be right at 7-9 lbs depending on rpm’s and mine is 7100.
Count the teeth total 64, almost perfect!

So that is my plan to get to 9 lbs, more work; I see light at the end of the tunnel on my stock internals without messing with the fuel system (besides TS and P.E. of course.)

I hope all of this taking the long way home steps I am doing is helpful to some new guy who just want to make 7 or 9 lbs safely. Skip past all of the BS I have done add larger injectors and reflash your ECU then keep your teeth count correct while under 65 teeth total because they don't even make a bigger belt for our kit….

So there you have it, 9 pounds safely. The only thing missing was the fact that I started from the very beginning with the wrong teeth and I don't even blame ATI for that after this talk.

And remember, "There aren't any authorized installers only authorized dealers", don't let some installer say otherwise.

Words to live by man, because this has been one serious project but I am just a pulley swap away from a very safe 9 lb setup.

The beauty of it is that when flashed to 9 lbs I am open loop anyways at that level and beyond so any A/F that would be incorrect because of this while in closed loop never effected me

So if and when I get time it's back to swapping pulleys.

This all started by me asking for a different pulley. ATI didn't try to sell me one; they help me fix my current setup with what I already have. Kudo's to them.

38 +26 64 that will be my setup when I am done and I will be able to run it all day.

Next up? HR4 BOV. I hope all of this isn’t a big “duh” to all of you, it wasn’t to me.

12SECZ

 

DUH!!!!

Max, I'm not totally clear on what you are trying to say. Do you have pictures of the belts and where they go, labeled with the tooth count you are talking about?

 

3rd paragraph up in my original post above has a link on that sorry for the confusion.

 

This was bothering me last night as I froze my azz off.

How can we all have the same belt and 65 teeth from 7 PSI all the way up to 15 PSI?

i KNOW SOME HERE REBUILT THEIR MOTORS OR ARE IN THE PROCESS OF DOING SO HOW ARE YOU GOING TO RUN 15 psi WITH 65 TEETH AND THE SA

ME BELT.

You know what, sorry for the cap I am not retyping that, I am not yelling my fingers are numb from the cold and I am going to sleep,. I could retype it all but you get the idea.

15 PSI 65 teeth = how?

Be back in about 8 hours ahhh sleep.

 

Maybe it works like sprockets on a motorcycle. A larger crank pulley and a smaller supercharger pulley both increase boost and yet potentially keep the same overall number of teeth. No?

 

This is correct. It could potentially get even more complicated on the S/C because they use a 2 stage belt drive (4 pulleys total), but maybe the middle pulleys in the drive never change - not sure about that.

For instance, you could have a 38 and a 26 tooth pulley, which would give you a 1.462:1 ratio (this is an example, and I'm ignoring middle stages of the actual procharger setup). You could use the exact same pulleys, but reverse their order, and now you have a 0.684:1 ratio (same belt size, same number of teeth). A 39/25 setup would yeild 1.56:1 and a 40/24 setup would give a 1.667:1 ratio, all with the same number of teeth.

On belt lengths, as long as you have enough adjustability you can adjust to keep the same belt length. Look on a mountain bike for example. They have a huge tensioner adjustment, but can use the same chain for not only a huge number of ratios (what are they up to now, 27 or 30 speeds?), but for a huge difference between the maximum and minimum ratios as well (granny gear vs. high speed gear).

-D'oh!

 

Thanks for the bike gear anolgy, yes it makes sense now, my belt is maxxed out now at full tension with nowhere to go.
Others will eventually have stretched belts so bad they will need new ones I guess.

 

TTT (To the Top)

OK I just learned that some are getting sent a 40 tooth pulley for 9 pounds, I was sent a 41. More teeth on this pulley equals more boost no wonder I made 11 pounds!!!

Pisses me off in a way but I have come too far to let that bother me.

So now I have
41 + 25 = 11 pounds
41 + 26 = 10 pounds (belt waaay too tight and rubs.)
41 + 27 = 9 pounds (had to custom order a larger belt, still waiting on it. ATI sent me a free 27, I originally was given a 26.

So I get a 26, everyone else gets a 27. Others get a 40, I get a 41. Almost makes me want to make a phone call but I am gonna let it go man...

Please if anyone is running more than 7 pounds with the Procharger then post your exhaust setup, intake setup, pulley teeth count and boost level.

It can only help serve others and hopefully detemine what is the best setup for future ATI owners ot those wanting more boost.

If my belt fits and works well then I will share with the group the part number, there are still about 80 of them in another state in a wharehouse (Gates Belt) and is is 7/8 in bigger giving you more flexibility when running differnt pulley combo's.

I have a 38, 41, 25, 26 and 27.

I am using the stock fuel pump and a 9 pound Technosquare reflash with P.E. 380cc injectors and my car just through a rich condition code

I would think at 440cc's others would see this code too? I am not real concerned about the code right now, actually I was lean with a white plug at 11 pounds so I am happy to see that code when I dropped to 10.

 

I might be able to cough up some info too cause the UPS guy just brought 2 big boxes to my door step. Unfortunatly im sick as a dog so im gonna staying in bed. Until then, are you looking for teeth counts Max?

 

Yes absolutely !! Hope you feel better.

 

Wait, did I jut read you got the blower?

Congrats man! 350+ RWHP here you come! Maybe more but at least that at a minum (woop V8 territory daily.)