rr racing udp (underdrive pulley)

If the rr is the same diameter as the ur then I can hook ya up with belt numbers. I think they are in a how-to thread but think how-to was written based upon the ur pulley, not the rr. **EDIT** I was wrong. the how-to was for rr & here's a quote from the thread about belts........"Dayco part numbers 5050450 and 5040355 are what I have installed currently with my RR-Racing UDP. Dayco is carried by the Advance Auto Parts around here." And IIRC the gatorbacks I just bought for mine with the ur udp are the same as those mentioned in the quote.
 
Last edited:
I really want to do this mod...especially for ~$100. My only concern is slight loss in AC. It's been mid 90's so far here, and every little bit of AC is smiled upon.
 
i12drivemyMP5 said:
If the rr is the same diameter as the ur then I can hook ya up with belt numbers. I think they are in a how-to thread but think how-to was written based upon the ur pulley, not the rr. **EDIT** I was wrong. the how-to was for rr & here's a quote from the thread about belts........"Dayco part numbers 5050450 and 5040355 are what I have installed currently with my RR-Racing UDP. Dayco is carried by the Advance Auto Parts around here." And IIRC the gatorbacks I just bought for mine with the ur udp are the same as those mentioned in the quote.

same #s you mean?
 
Watarski said:
I really want to do this mod...especially for ~$100. My only concern is slight loss in AC. It's been mid 90's so far here, and every little bit of AC is smiled upon.
I live in TX & it's always hot here. I use AC all year without problems.
 
how hard is the install? i read the how to but it seems kinda hard. how many pulleys are actually being replaced along w/ how many belts? just 1? or 2?
 
where can gatorbacks be bought? that thread is too confusing for me to even being to decipher. numbers galore and no one seems to know which numbers go with which manufacturer and which company's udp... Gatorbacks numbers for RR-racing udp?
 
Gatorbacks at Autozone, about 50.00 for both. From that thread it seems that the same belts will go with both unorthodox racing & rr udp's WITH AC. Goodyear: 4050457 for the AC/PS and the 4040360 for the Alt/WtrPmp
Gates: K050446 and K040355
 
ac = air conditioner.

PS = power steering. One belt powers those, running to those pulleys.

The other powers the alternator and water pump.
 
amsgator said:
so what are the gatorbacks numbers? what do you mean rr udps w/ AC?
Some people have AC, those belts are longer. Some people don't have AC, those belts are shorter. I gave you numbers for ur OR rr udp assuming you have AC. If you don't have AC, then go back to that thread I posted. There's a post with part numbers for cars without AC in it somewhere.
 
i do have ac. :) so there is only 1 pulley but 2 belts? o sorry i didnt see you had goodyear there, sorry!
 
amsgator said:
i do have ac. :) so there is only 1 pulley but 2 belts? o sorry i didnt see you had goodyear there, sorry!
Yes, 1 UDP, 2 grooves, 2 belts. 1 goes around the udp/water pump/alt & the other goes around the udp/power steering pump/AC, just like the factory ones, only a little shorter.
 
i12drivemyMP5 said:
Gatorbacks at Autozone, about 50.00 for both. From that thread it seems that the same belts will go with both unorthodox racing & rr udp's WITH AC. Goodyear: 4050457 for the AC/PS and the 4040360 for the Alt/WtrPmp
Gates: K050446 and K040355

FYI...the last 3 digits are the total diameter/length of each belt. So 457 and 360 and 446 or 355 (cm I guess?)
 
Back