Boost loss

[9397SVTs]

Sounds pretty good as well.

 

[98 Saleen Cobra]

@98 Saleen Cobra ?

On it!

OP what size belt are you running? and are you a 8rib? Tensioner needs to be at about 90-95% maxed out. That's how I run mine.. 2.75" upper and 15% O/D crank 8 rib gates belt..

It's so tight I can't get it on without removing the AC pulley.. It needs to be tight AF.. I know that they make a 113.X and a 112X you're going to be in that range for the 8rib..

Also what tensioner are you running? needs to be a thump tensioner.

Someone who said that the having a tight belt will kill main bearings in in correct as long as there is some play in the tensioner it'll tension what it's designed to the key is that the belt will stretch and is less prone to slipping because really 95% tension when the belt is new turns into 80% tensioner after like 1-2 passes.

 

[JGDogg10]

On it!

OP what size belt are you running? and are you a 8rib? Tensioner needs to be at about 90-95% maxed out. That's how I run mine.. 2.75" upper and 15% O/D crank 8 rib gates belt..

It's so tight I can't get it on without removing the AC pulley.. It needs to be tight AF.. I know that they make a 113.X and a 112X you're going to be in that range for the 8rib..

Also what tensioner are you running? needs to be a thump tensioner.

Someone who said that the having a tight belt will kill main bearings in in correct as long as there is some play in the tensioner it'll tension what it's designed to the key is that the belt will stretch and is less prone to slipping because really 95% tension when the belt is new turns into 80% tensioner after like 1-2 passes.

112.4” gates HD. Yes it is 8 rib. I had the thump tensioner maxed out and needed two people to pull the belt over the water pump pulley. It’s a 15% od with a 2.95 griptech. I’ll see if I can get a video up, but the belt is tight enough to make a bass guitar noise when you touch it ha.


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[JGDogg10]

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[98 Saleen Cobra]

Can you draw out your belt routing?

 

[98 Saleen Cobra]

Shot you a DM. Going to be easier to text or talk on the phone.

Svtp I’ll make sure he reports back the findings

 

[96dreamer]

The rpm belts don’t come in a long enough length. Yea I was wondering about that. It’s weird because i had on regular belt on that was bigger than this new green belt and it is making about the same amount of boost. Wasn’t quite as tight as this one


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FYI I've got an 8 rib 114.5" gates rpm belt on my setup

 

[JGDogg10]

FYI I've got an 8 rib 114.5" gates rpm belt on my setup

Oh damn nice. I haven’t looked at them in a while I guess. When they first came out they were very limited on sizes and they were all smaller. I’ll check it out

 

[JGDogg10]

Just looked on gates website and the biggest 8 rib rpm belt they say they have is 108.8”..

 

[96dreamer]

Yeah that list is not up to date. The rep for gates used to post on here every now and then and would take requests for belt lengths. I believe the 113.1" is because of a request I made in the past but never ended up using.

 

[JGDogg10]

Yeah that list is not up to date. The rep for gates used to post on here every now and then and would take requests for belt lengths. I believe the 113.1" is because of a request I made in the past but never ended up using.

That’s badass. Might need to figure out exactly what length I need and then hit them up.

 

[01yellercobra]

On it!

OP what size belt are you running? and are you a 8rib? Tensioner needs to be at about 90-95% maxed out. That's how I run mine.. 2.75" upper and 15% O/D crank 8 rib gates belt..

It's so tight I can't get it on without removing the AC pulley.. It needs to be tight AF.. I know that they make a 113.X and a 112X you're going to be in that range for the 8rib..

Also what tensioner are you running? needs to be a thump tensioner.

Someone who said that the having a tight belt will kill main bearings in in correct as long as there is some play in the tensioner it'll tension what it's designed to the key is that the belt will stretch and is less prone to slipping because really 95% tension when the belt is new turns into 80% tensioner after like 1-2 passes.

I don't know that I'd say incorrect as I had the chewed up front main bearing to show for playing the tight belt game. So I'm not just saying things because of what I saw on the internet. I don't want Justin to go through what I did.

When I swapped to the 8 rib I ran a Thump tensioner and a standard belt. I was pullied for 19-20psi with an F1A on a big bore stroker, full exhaust, and ported intake. So it was spinning good. And the tensioner was always in the halfway point and I could get the belt off and on by myself. And when I pulled that shortblock apart (for other reasons) the bearings were fine.

I will admit one of the reasons I like Procharger is because of the more aggressive step up ratio. Don't need to run such a small blower pulley.

 

[JGDogg10]

I don't know that I'd say incorrect as I had the chewed up front main bearing to show for playing the tight belt game. So I'm not just saying things because of what I saw on the internet. I don't want Justin to go through what I did.

When I swapped to the 8 rib I ran a Thump tensioner and a standard belt. I was pullied for 19-20psi with an F1A on a big bore stroker, full exhaust, and ported intake. So it was spinning good. And the tensioner was always in the halfway point and I could get the belt off and on by myself. And when I pulled that shortblock apart (for other reasons) the bearings were fine.

I will admit one of the reasons I like Procharger is because of the more aggressive step up ratio. Don't need to run such a small blower pulley.

I’ll agree with that, wish the ratio was a little more aggressive.

So just a quick update, I was using a 114.5” belt at the beginning and was having to space out my ac compressor. Took all the spacers out and put on the 112.4” belt which was tight, but I think when I was putting it on the belt might have been hung up on something so felt tighter than it was. Sent some videos and pics to Chris(98 saleen cobra) and my tensioner was def not at a place where it was as “maxed” as I thought it was. Went out and bought a 110.2” belt because that’s the next size down, wouldn’t even come close to getting on. So back to the 112.4” belt and I spaced out the ac compressor just under 1/2” with billet spacers. The belt was hard to get on, but went on and my tensioner still has a little bit of room, but it’s def tighter then at the beginning. Finished that last night and got an updated tune yesterday, so loading the new tune and will drive it shortly. I’ll update after the drive. Fingers crossed it works. Otherwise I’m at a loss. Chris was running an almost identical setup and had no slip, so hoping for the best

 

[omj]

Does a RPM belt slip less than the green or standard belt?

 

[JGDogg10]

Does a RPM belt slip less than the green or standard belt?

From what I understand, there is little to no stretch on it. So stays tighter. But need to make sure you have the most correct size for the setup

 

[JGDogg10]

Well drive the car, same issue. Makes me believe it’s not belt slip. The first combo of belts and spacers was no where near as tight as the new combo and still made the same amount of boost. Wouldn’t make sense for the belt to be even tighter and not see any difference whatsoever in boost numbers. Still gonna take the car for one more run tomorrow after cleaning the hell out of the supercharger and surrounding areas to see if there is belt dust that shows up…

Now I’m just pulling at straws to see what else could be causing this.

I’m open to everything, throw some ideas out. At this point nothing is off the table..

 

[JGDogg10]

So ended up driving it tonight, pulled super hard again in 2nd gear, saw around 19-20lbs and third was a dud, around 15 or so. No signs of belt dust that I saw or felt. Gotta be something else.

 

[98 Saleen Cobra]

I don't know that I'd say incorrect as I had the chewed up front main bearing to show for playing the tight belt game. So I'm not just saying things because of what I saw on the internet. I don't want Justin to go through what I did.

When I swapped to the 8 rib I ran a Thump tensioner and a standard belt. I was pullied for 19-20psi with an F1A on a big bore stroker, full exhaust, and ported intake. So it was spinning good. And the tensioner was always in the halfway point and I could get the belt off and on by myself. And when I pulled that shortblock apart (for other reasons) the bearings were fine.

I will admit one of the reasons I like Procharger is because of the more aggressive step up ratio. Don't need to run such a small blower pulley.

I gotcha, thats interesting because really the belt sitting where ever on the tensioner as long as it has play is still tensioning at whatever it's designed to be tensioned at.. I run mine at about 90-95% on a fresh belt then it stretches and sits at 85-90% after some passes.

I've been working with Justin (OP) the past few days.. All but ruled out belt slip..

He's running the stock H-pipe with cats, and EGR and all the smog shit for Cali.. There might be some other issues happening with the EGR valve that he's going to try. Also the Vortech is a used unit and it doesn't sound great I'll be honest... But the boost dropping in 3rd is weird and I don't believe is blower related.

 

[robvas]

Could your crank pulley be slipping?

 

[JGDogg10]

Looking at the assembly of the crank pulley, not sure it’s possible to slip because of the torqued bolts going through the outer shell and into the hub with the belt riding on that outer shell.