new tensioner/belt ideas

[dmw319]

long story short, i dont like the way the tensioners setup for the powerdyne is set up and after the belt loosens up some from use, you can only tighten it down so much cuz theres no room for leverage and i havent been hitting full boost... so well me and a fellow mechanic at a GM performance shop have been thinking of ways to redo my tensioner for my serpentine belt. we came up with some cool ideas, all of which required a substancial amount of time and money (1.bolt tightened with ratchet, only problem is you could EASILY overtighten and we all know what problems we would run into their or b. swapping all pullyes on the system to their opposite which would make the pulley on the s/c ribbed and basically flip the belt around). but another easier way we thought of was to get a) a stronger belt that is less resistant to stretching after a good amount of use like a gates blue belt or b)find a way to get a custom belt that is ribbed on both sides (lots of VWs have belts like this) that way my smooth s/c pulley will be running on a ribbed belt side instead of a smooth one. the problem is.. i need the belt to be about 102-102.5" and i cant find anything in that size. anybody know of any stores or sites that could help? or any other cool ideas would also be appreciated..

[Mighty Thor]

Re: new tensioner/belt ideas

(1.bolt tightened with ratchet, only problem is you could EASILY overtighten and we all know what problems we would run into their or b. swapping all pullyes on the system to their opposite which would make the pulley on the s/c ribbed and basically flip the belt around). but another easier way we thought of was to get

If you guys find a way to improve this then I'll be all over it. I don't recommend you over tighten it because it will put a lot lateral stress on your accessories, esp. the Alt.

I would recommend you spray the belt with a belt dressing a day before the race, run it, then loosen up the tensioner. On the day of the race, tighten it till there's little play on the belt.

a) a stronger belt that is less resistant to stretching after a good amount of use like a gates blue belt or

In the beginning we discussed about belts and I have concluded that Gates belt is the worst. They stretch out and then they tighten. They also get hot. Many PD SC agreed with me. Dayco is the best and so is Gator. These belt don't stretch out as much and are a lot more sturdier and doesn't heat up or stretch out too much.

b)find a way to get a custom belt that is ribbed on both sides (lots of VWs have belts like this) that way my smooth s/c pulley will be running on a ribbed belt side instead of a smooth one. the problem is.. i need the belt to be about 102-102.5" and i cant find anything in that size. anybody know of any stores or sites that could help? or any other cool ideas would also be appreciated..

This was another thing that was discussed in the beginning. A '94 Corvette used a double ribbed belt (Gates). It's a hard find, but I found one at Corvette Specialty for $50. The problem is it's about 6"-8" too short. I contacted the manufacturer but they are not willing to go bigger because it will not be cost effective for them. We also discussed about ditching the water pump with electric one to see if this belt would work. But so far nobody has tried it.

[NCState98]

Re: new tensioner/belt ideas

I think you're running into all the same questions and ideas that eventually pass through the head of every powerdyne owner. I was pretty close to coming up with a way to run a ribbed belt, and even have the ribbed pulley for the SC and other various pullies to play around with for tensioners and an electric water pump, but as you know I got bored with that and am gonna play around with a procharger instead. IM me sometime Dave and I'll let ya know what I had come up with.

[dmw319]

Re: new tensioner/belt ideas

thanks for the reply guys. i got a one inch shorter belt today to see if i could try and just tighten my belt up to try and get more psi out of it. so now im running a 102" belt, but im still only seeing 3-4 psi and the belt screeches when i rev in neutral. it doesnt slip on the road, but i cant get enough boost :(

[dmw319]

Re: new tensioner/belt ideas

tightened down that sucker more today and now im seeing 5-6 consistenly. but i should be seeing 9-10 :(

[Mighty Thor]

Re: new tensioner/belt ideas

I think you're running into all the same questions and ideas that eventually pass through the head of every powerdyne owner. I was pretty close to coming up with a way to run a ribbed belt, and even have the ribbed pulley for the SC and other various pullies to play around with for tensioners and an electric water pump, but as you know I got bored with that and am gonna play around with a procharger instead. IM me sometime Dave and I'll let ya know what I had come up with.

From what I know Mach Kit experience more slippage than PD. It's probably because they are using the stock tensioner and there's little you could do about that one.

DMW319 what kind of belt did you get? New belt stretches, just a couple more tightening.

[dmw319]

Re: new tensioner/belt ideas

i got just a regular old belt, not even the polycog. only cost 26 bucks at pepboys.

[BryanMills]

Re: new tensioner/belt ideas

I've been making my own PD mounting kit, which is finally finished . I'm just waiting for a warmer NH day to install it. The whole reason behind making my own was to use the stock tensioner and make the mounting more rigid. I made an offset lower mounting bracket so that the plate will mount 1" higher (to get it away from the oil filter) and about 1 inch to the left so that I can use the idler pulley mount as one of the mounting points since that is a very solid mounting point. The third mounting point is on the alternator so that the stock tensioner will have an unobstructed movement. If I find that I need more tension, my plan is to add a bracket to the tensioner pulley bolt and add more spring force there. However, I believe there will be enough leverage if I select the correct belt length.
Hopefully, I will have it installed by Spring. If it works, I'll post how to make all the pieces and where I bought all the stock. Two of the brackets are fabricated from 1/4" X 1" steel (can't weld aluminum with my machine) and the other braket is a 2.5'" piece of 1" OD aluminum tubing with an ID of 1/2". That's the part that attaches to the idler pulley.

[BryanMills]

Re: new tensioner/belt ideas

The Goodyear Belt chart shows the following belt sizes:
Part Number---Metric P/N-----Size
4061020-------6PK2590-------102"
4061025-------6PK2605-------102.5"
4061030-------6PK2615-------103"
4061037-------6PK2635-------103.75"

Get the idea?

I got mine from Summit Racing but I had to wait about 6 weeks to get it.

[dmw319]

Re: new tensioner/belt ideas

makes sense, but dont you run into the receiver drier for the A/c system and its bracket when you move the blower to the left? i have that problem now with the stock brackets!

pictures are going to be the best way so the rest of us can see. good luck!

[BryanMills]

Re: new tensioner/belt ideas

I don't have a powerdyne plate. Never did. I made my own from 3/8" aluminum so my SC is mounted in a different location on my plate than yours would be. I haven't checked for the AC drier obstruction yet. But when I eye-balled it, it looked OK. I'll find out when I do the install. If I do have a problem, I'll just have to deal with that.

If you think about it, there is quite a bit of room where the SC will physically fit in that engine compartment; it's just a matter or attaching it to valid mounting points so it will actually work without moving. That is where the limitation comes in. My lower bracket is L shaped and welded to the side of a round steel tube to give it the offset that I needed to completely clear the oil filter.

Getting creative with the brackets will allow you to put the plate wherever you want. Remember, there are valid mounting points on the other side of the engine that can be brought over with tubing mounted from one side of the engine to the other to make a super strong mounting rail if that's what you needed. I considered that at one point but settled on an easier method.

[Mighty Thor]

Re: new tensioner/belt ideas

I've been making my own PD mounting kit, which is finally finished . I'm just waiting for a warmer NH day to install it. The whole reason behind making my own was to use the stock tensioner and make the mounting more rigid. I made an offset lower mounting bracket so that the plate will mount 1" higher (to get it away from the oil filter) and about 1 inch to the left so that I can use the idler pulley mount as one of the mounting points since that is a very solid mounting point. The third mounting point is on the alternator so that the stock tensioner will have an unobstructed movement. If I find that I need more tension, my plan is to add a bracket to the tensioner pulley bolt and add more spring force there. However, I believe there will be enough leverage if I select the correct belt length.
Hopefully, I will have it installed by Spring. If it works, I'll post how to make all the pieces and where I bought all the stock. Two of the brackets are fabricated from 1/4" X 1" steel (can't weld aluminum with my machine) and the other braket is a 2.5'" piece of 1" OD aluminum tubing with an ID of 1/2". That's the part that attaches to the idler pulley.

I'm very curious. Post some pics now.

When Vector Perf. first made the PD kit for our V6 in late 95 they were using the stock tensioner and they experienced a lot of slippage. Even their LT1 PD kit which runs on the rib side was the same.

Good luck

[The Crow]

Re: new tensioner/belt ideas

This weekend I installed a 102.5" belt using the John D wrap and replaced the stock tensioner pulley with a smaller pulley. I get little to no slippage and I am hitting 6.5 to 8 psi constantly. I love it!! I am so happy with my kit now.

[dmw319]

Re: new tensioner/belt ideas

what size pulley is on the stock tensionr and what size did you put on? what size is your s/c pulley?

[The Crow]

Re: new tensioner/belt ideas

I got the original SC pulley from RKSport, 6.5 psi. I don't know the size of the stock tensioner or the new one that I installed. I will measure them and post them up.