What belts for Evosport UDP's?

[Justin(OKC)]

I've searched and am just not having very good luck. I am having to replace my water pump and am going to go with the Stewart unit, but I want to do the other parts as well to make things new again. I'll get a new thermostat, but I need belts. The issue is that I know the stock belt sizes will not work with my UDP's. Does anyone know what sizes I need to order? Your help is greatly appreciated

[Aradaiel]

Why won't they work? The tensoner should take up the slack, no?

[Justin(OKC)]

I could have sworn that the belts were smaller with the UDP's. Are they not? I didn't install them on this car but I know I had to use smaller belts on other cars that I have done UDP's on.

[hc1001]

u can email them and they will tell u the sizes...
they have different sizes for different alternators, and package.
i have a bosch udp kit.
e36 M3 Performance Pulley Kit with Bosch Alternator - 6 Rib 62'/1570mm = $20.00
e36 M3 Audiophile Pulley KIt with Bosch Alternator - 6 Rib 61.2'.1555mm = $20.00

if u dont have a bosch alternator, jus email them with your last name and they should be able to pull up your order. or jus tell them what alternator and package u have.

[marc1119]

The belt is "longer" with a UDP kit..because the pullies are larger, that is what makes the accessories underdriven...

I too, run Evosport pullies, alt, ps, and H20 pump.... my kit came with a 62 inch 6 groove belt also...

is there no part number or "mm" size stamped on the old belt any longer? Is it worn off?

The A/C belt is still stock................. 5 groove 35.5 inch (IIRC)...


So when you say belt SIZES...It only applies to the main accessory belt..The A/C belt remains stock size..Nothing changed in the underdrive upgrade..to the crank pulley or A/C pulley...

[Justin(OKC)]

cool, thanks guys!!

[Justin(OKC)]

I'll tell you, people at part stores are just unbelievable. I call Evosport to verify what I need and they tell me it is a 62" 6 rib belt. So I go to PepBoys...they can't do anything without a part number. So, do any of you guys know the part number for this belt? Thanks!!

[Justin(OKC)]

For someone's future reference it was a 6PK 1577 belt It was actually a 62 5/8" belt. If anyone would like the other number on the Gates belt, I can get it for you.

[Toon///Man]

For someone's future reference it was a 6PK 1577 belt It was actually a 62 5/8" belt. If anyone would like the other number on the Gates belt, I can get it for you.

Thought you were selling her, Justin?

[Justin(OKC)]

I thought I had it sold. I guess, if the right offer comes along I will part ways with it. I'm afraid I will miss the car too much. I'm considering getting a 335i sedan for a daily driver and promote the M3/4 to weekend/sunny day duty. When the new M3/4 comes out....all bets are off. If it is way too heavy, I'll consider selling this M3 for a new M coupe. I'm just keeping my options open. The car is paid for so really, I can do whatever I want with it. My water pump went out and I put in a new Stewart pump....wow, that thing makes the stock pump look like a toy!! My car is not sick anymore, so I'm looking forward to doing some driving!!!

On a different subject, send me an email or a PM and tell me what kind of law you practice.

[Toon///Man]

I thought I had it sold. I guess, if the right offer comes along I will part ways with it. I'm afraid I will miss the car too much. I'm considering getting a 335i sedan for a daily driver and promote the M3/4 to weekend/sunny day duty. When the new M3/4 comes out....all bets are off. If it is way too heavy, I'll consider selling this M3 for a new M coupe. I'm just keeping my options open. The car is paid for so really, I can do whatever I want with it. My water pump went out and I put in a new Stewart pump....wow, that thing makes the stock pump look like a toy!! My car is not sick anymore, so I'm looking forward to doing some driving!!!

On a different subject, send me an email or a PM and tell me what kind of law you practice.

Yeah, I've installed 2 Stewarts and one is going in my car in a couple of weeks. I blew the headgasket (I hope that is all) instructing BMWCCA at MotorSports Ranch in August and radiator is full of oil. :( I'm gonna replace everything cooling related during the repair/rebuild.