what size belt for m90 with 2.57 pulley? need help asap

[snopro442]

I have the m90 roush s/c on my 06 gt and the rest of the pulleys are all stock size, I installed a 2.57 pulley and now the belt is to big, anyone else do this and have to change the belt size? if so could you please post the part number or any info that you have about doing this? thanks for your help.

 

[skwerl]

You need to change the idler pulley directly below the blower snout to a 90mm. You can buy a bling pulley online for big bucks or you can go buy a generic idler pulley from the corner auto parts store.

One of the guys over on fnsweet forum posted a thread a while back with all the M90 belt sizes and part numbers for different years. For most of them Roush is your only source because they are an odd size. I bought a spare and keep it in my trunk just because a broken belt could put my car down for a week.

 

[KyleB]

I literally just gave a vmp oversized idler away...

 

[Captainstr8edge]

You need to change the idler pulley directly below the blower snout to a 90mm. You can buy a bling pulley online for big bucks or you can go buy a generic idler pulley from the corner auto parts store.

This.

 

[DiMora]

You need to change the idler pulley directly below the blower snout to a 90mm. You can buy a bling pulley online for big bucks or you can go buy a generic idler pulley from the corner auto parts store.

One of the guys over on fnsweet forum posted a thread a while back with all the M90 belt sizes and part numbers for different years. For most of them Roush is your only source because they are an odd size. I bought a spare and keep it in my trunk just because a broken belt could put my car down for a week.

That's me.

Here...have fun, guys:

Roush 6 rib belts:
2005/2006 FEAD M90 belt: RPP# R07020015 -13-AA / PN 401967 / 131.732"

2007/2008 FEAD M90 belt: RPP# R07020032-13-AA / PN 402065 / 132.441"

2009/2010 FEAD M90 belt: RPP# R07020063-13-AA / PN 404078 / 132.638"
2007/2008 TVS / P51 belt: RPP# R07020041-13-AA / PN 403805 / 134.370" / (135" OC)*
There is also another 6 rib TVS single belt Phase Two belt that came out PN 421160 3378MM / 132.992”
Roush P51B Dual Belt:
1st Sheave: PN 404168 Stock Mustang GT Belt
2nd Sheave: PN 404306 1670MM / 65.748”

Goodyear 8 Rib Gatorback belts (no 6 ribs available in Roush lengths from Goodyear):
4081295 8PK3290 8 129.5 130.25
4081360 8PK3455 8 136 136.75


DAYCO 8 rib belts (Top width 1.10” .169” thick) (No 6 ribs in Roush length from DAYCO):

[FONT=&quot]5081325 132.50 8 W Profile EPDM, Aramid Reinforced Rubber [/FONT]

[FONT=&quot]5081363 136.30 8 W Profile EPDM, Aramid Reinforced Rubber [/FONT]

[FONT=&quot]GATES belts (6 and 8 rib):[/FONT]

[FONT=&quot]K061360 [/FONT][FONT=&quot]136 5/8 6 Micro V belt Width 13/16 (20mm) 40°rib angle[/FONT]

[FONT=&quot]K081331 [/FONT][FONT=&quot]133 3/4 8 Micro V belt Width 1 3/32 (28MM) 40°rib angle[/FONT]

[FONT=&quot]K061360HD[/FONT][FONT=&quot] 136 1/2 6 13/16 (20MM) 40° FLEET runner Heavy Duty[/FONT]

[FONT=&quot]K081331HD[/FONT][FONT=&quot] 133 ¾ 8 1 3/32 (28) 40° FLEET runner Heavy Duty[/FONT]

Keep in mind that with an X-Acto knife and some patience, you can easily cut a 10 or 8 rib belt down to a 6 rib by removing the extra unwanted ribs. Like this:

OP...you were given the easy answer - you need an 85 or 90MM idler immediately BELOW the supercharger snout pulley. Autozone, O'Reilley's, Schuck's, Pep Boys, Advance Auto etc. will all have what you need for cheap.