Do these belt sizes sound right to you?

[Steel City Pimp]

Ok when I put the pulley on and had my car tuned, I got a belt from napa. I was told it was a 74" belt but when I gave them that part # over the phone to them today, they said it's a 74 5/8" belt. They also told me the next smallest one is a 73 3/4" and the next bigger size is a 75 1/8. Does this sound correct to everyone or is this guy crazy. I always hear people say 74" or 74.5" etc. Im asking because tomorrow my 100mm idler will be here and Im not sure the current belt will be big enough. According to the people I bought the idler from, I will be able to reuse it if I still have room remanding in the tensioner. When looking at my tensioner today I haven't even hit the half way mark so there is still room left in the tensioner. What do you think? Sorry for the long post.

Thanks
:beer:

 

[cobrapete03']

That's what I'm using 74 -5/8"...It will work good...And those other sizes are right...I saw the ordering catalog from Napa with my own eyes...


-pete:coolman:

 

[Steel City Pimp]

Originally posted by cobrapete03'
That's what I'm using 74 -5/8"...It will work good...And those other sizes are right...I saw the ordering catalog from Napa with my own eyes...


-pete:coolman:

Thanks Pete! What pulley and idler are you running?

 

[cobrapete03']

280 and metco 100mm


-pete:coolman:

 

[Steel City Pimp]

Originally posted by cobrapete03'
280 and metco 100mm


-pete:coolman:

Im running a 2.93 and putting a 100mm idler on. Do you think this belt will still work or will I need the 75 1/8" belt???

 

[cobrapete03']

I wouldnt go any higher than 75-1/8" but I think you will find the L pulley and 74-5/8" should work out fine...


-pete:coolman:

 

[Steel City Pimp]

Originally posted by cobrapete03'
I wouldnt go any higher than 75-1/8" but I think you will find the L pulley and 74-5/8" should work out fine...


-pete:coolman:

I hope so! I ordered a larger belt from napa so they would have it in stock in case I need it. We will see tomorrow when the tensioner gets here! Please more opinions guys. Thanks in advance

:beer:

 

[Steel City Pimp]

ttt

 

[03DOHC]

Originally posted by Club "33"
Im running a 2.93 and putting a 100mm idler on. Do you think this belt will still work or will I need the 75 1/8" belt???

The Gates 0745 will fit better with your combo. I don't think the Gates 0740 (74 5/8") will fit. If you can manage to get it on there it'll probably be too tight. Which 100mm idler did you buy?

 

[Steel City Pimp]

Originally posted by 03DOHC
The Gates 0745 will fit better with your combo. I don't think the Gates 0740 (74 5/8") will fit. If you can manage to get it on there it'll probably be too tight. Which 100mm idler did you buy?

Metco Black Powder Coated. Thanks for the info. Im going to have to wait and see. The idler will be here tomorrow.

 

[03DOHC]

I've installed a couple of 2.93/100mm Metco/Gates 0745 combos. The Gates 0745 is the right belt.

 

[broke7]

I just got a NAPA/Gates 740 belt, it says 74 5/8th on the back, but all the major vendors will list it as a 74" Belt


The gates/napa 740/74" belt hasnt failed me yet, ive run my best MPH with it

2.80 RR Billetflow 100mm Idler

 

[trey193]

I agree with Broke the 74 Gates belt is the one to use, All the gates/napa are longer than advertised and will stretch with time as well, get the 74 Mike.

 

[HIGH ROLLER]

If you are using the 2.80 pulley with a 100mm idler you will need the 74 inch napa belt,if you are using the 2.93 pulley with the 100mm idler you will need to go up a 1/2 inch bigger for proper fit IMO. I currently am using the 2.80 pulley with a 90mm idler and using the 74.5 gatorback belt with good results,tensioner is right in the middle where it should be.

 

[Steel City Pimp]

Thanks again guys! The pulley is a 2.93 and the belt that is on there now is the napa/gates 74 5/8" AKA 74"!!!! With a 100mm idler do you guys think this belt will still work??? Will this be to tight??? If you look at the tabs on the front of the tensioner and push on the belt a little, I can see I haven't even used half of the tensioner distance. I think the belt stretches for sure but will this still be too tight??? Im going to go to napa today to pick up the 75 1/8" AKA 74 1/2" belt just in case!!! And to top it off I got the pulley today but there was no bracket. They are going to overnight a bracket but I could be cutting it close for track time. I rather have the extra belt on hand just in case. Now there calling for rain too . Is this God's way of telling me my buddy's et streets are going kill my irs!!!! I got a AAA membership just in case!!

Mike

 

[jtfx6552]

Are you guys talking about 90 and 100 mm idlers in the stock location, or an added idler?

I have a RR 2.75 with a Gates K080074. It seems a little loose. On the dyno at the top of the pull, the tensioner was almost against the stop. I am wondering if I should geta 735, or possibly put my 90 mm steel added idler back on with the 74?

Right now the RR seems to making a of of belt dust, but my boost gauge seems to be registering high, and the dyno curve did not indicate slip.

 

[Steel City Pimp]

Originally posted by jtfx6552
Are you guys talking about 90 and 100 mm idlers in the stock location, or an added idler?

I have a RR 2.75 with a Gates K080074. It seems a little loose. On the dyno at the top of the pull, the tensioner was almost against the stop. I am wondering if I should geta 735, or possibly put my 90 mm steel added idler back on with the 74?

Right now the RR seems to making a of of belt dust, but my boost gauge seems to be registering high, and the dyno curve did not indicate slip.

JT,

Added 100mm idler. I just got back from picking up the 75 1/8" gates aka 74 1/2"!!! I'll let everyone know which one works best. Im thinking Im going to need the bigger one but we will see. Im thinking it's not healthy to max out the tensioner. You guys???

 

[03DOHC]

Originally posted by Club "33"
JT,

Added 100mm idler. I just got back from picking up the 75 1/8" gates aka 74 1/2"!!! I'll let everyone know which one works best. Im thinking Im going to need the bigger one but we will see. Im thinking it's not healthy to max out the tensioner. You guys???

The Gates 0745 is the correct belt for a 2.93/100mm Metco blower idler combo assuming the rest of your pulleys are the stock ones. And it is not good to max out the tensioner. Try to keep it in the middle of its range.

 

[trey193]

JT since you have Cats how much boost are you seeing with the 2.75??? Whats it peak @ and whats it drop to @ redline?

 

[Steel City Pimp]

Originally posted by 03DOHC
The Gates 0745 is the correct belt for a 2.93/100mm Metco blower idler combo assuming the rest of your pulleys are the stock ones. And it is not good to max out the tensioner. Try to keep it in the middle of its range.

Thats what I've been thinking as well. Im using just below half the tensioner span now with the 74".