ZZP Pulley Puller Question/belt change? 3.4 Here I come

[Liquifire]

This is a two part question:

1) I am planning to change my stock pulley out to the 3.4 MPS system and will probably go with the zzp mps and rent their pulley puller to change them out. What is the backing plate, what does it do, and do I need this to pull off the stock pulley or to put on the MPS hub?

2) If I run the 3.4 can I run the stock belt or will I need to get a new belt. If I need to get a new belt, who has them cheap? Any part numbers would be appreciated. I got this part number from zzp's website: 4060660- Is this the gatorback? Is this what I need? Who has it the cheapest?

I wont be doing this until I get the PCM from 3800 so it is still a couple of weeks off. Does anyone know how long they have been out of stock with the 3.5? I want to run the 3.4 but if I am knocking I am going to go with the 3.5.....yes I will get 104's and the pcm before dropping the pulley size.

Thanks again

[minichopper6hp]

I personally didnt have to change the belt to run a 3.4, its a little on the low side of the tensioner though. The belt number you posted above comes up as a gatorback 66 inch belt. You dont need the backing plate to install a mps hub, just to remove it.

[OH4CompG]

1. the plate is for removing an MPS hub so the puller has something to grab.

2. AFAIK you can run the stock belt but may have belt slip. I don't recall the smaller belt off the top of my head. Napa can look up a smaller size if need be.

3. I know a few people that are running a 3.4 without even a plog and getting no knock. You should be fine as long as you have a good tune. Watch for knock all the same though.

[Liquifire]

so I don't need the plate to remove the stock pulley....good. Does anyone know how long the stock belt is off hand? Is the gatorback a good brand of belt? I have it on now on the stock set up and have had no issues...

[TheOtherNick]

I run a 660 belt. It is pretty damn tight on the 3.5

[GTPJOE90]

gatorback is made by goodyear i think so yeah its a good belt im in the same boat as you man 3.4 here i come "in about a month - 2 months.

[Going Too Phast]

The part number from ZZP is for the belt made by Gates. ZZP has an article I believe where they claim that the Gates belt grips better than anything they tested (Gatorback, etc.). I got the Gates belts from ZZP and they seem to be good quality. NAPA's belts are supposed to be Gates IIRC. You don't need to get a new belt if yours is in good shape and if you switch to a 3.5 inch tensioner pulley. That is what I did. ZZP has them or if you got the part number I'm sure you could find it local. I think some people also swap one of the existing idler pullies which is already 3.5". I went that route instead of getting a smaller belt so I could use the stock belt size and it gives you slightly more belt wrap on the pulley, not that it should be a big issue at ~3.4" pulley sizes but it won't hurt.

[blueguy]

If your current belt isn't that great...then just pick up a new one anyways.

Also...if you want it to be pretty good and tight you can get a 658 IIRC...it is made for a 3.5"-3.25" area. Belt slip sucks...I had a 658 on a 3.1" and if I let off the throttle under a pretty good load...even in 2nd gear...you'd hear it...it sucked...so I got a belt for a 3.0" and actually noticed a little bit better response.