Vortech cog belt problems. Need advice
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 1,019
Likes: 4
From: az
Vortech cog belt problems. Need advice
My car is getting the finishing touches and it is destroying cog belts. It seems to only strip the teeth off the belts and leave the outside edge of the belt in tact. I am using a basically stock C5 Vortech kit with a T Trim and 32 and 24 teeth cog pulleys. I am using a smaller than stock belt that fits this application. The same thing happened with 34 and 26 pulleys also but it took longer. The motor is a forged 427. I guess I'm looking for others that have had cog belt problems also to tell me what caused their problems and how it corrected. I know this set up is not very good but it's what I have and there is no turning back at this point. I cannot figure out why the teeth would be stripped off and leave the outer portion of the belt in tact. Thanks for any help.
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 1,019
Likes: 4
From: az
Melting Slicks
Joined: Apr 2005
Posts: 3,418
Likes: 1
From: Chicagoland Area IL
Try backing off on COG belt tension as they do not stretch like Micro-V and too much tension can be detrimental. Also check cog pulleys for damage as this can shorten belt life considerably.
Mike
Mike
Melting Slicks
Joined: Jul 2004
Posts: 2,844
Likes: 144
From: Northern Ireland
He said get rid of the cog, and build a ribbed supercharger drive. NO cogs.
Cogs apparently require 100% perfect pulley alignment, and can be troublesome.
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Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 1,019
Likes: 4
From: az
The cogs are fine. Gates thinks that the belt isn't tight enough. They are looking at the belts to diagnose the problem. Then there is a possible problem with the brackets flexing. It's funny how Vortech will give advice and sell parts and then run away when it doesn't work the way they say it should.
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 1,019
Likes: 4
From: az
Call DTE!
Collections Hold
Joined: Aug 2002
Posts: 2,899
Likes: 6
From: Fort Wayne Indiana
A couple of things....
Our HD Vortech S/C Belt Drive Kit we engineered a couple of years ago was designed to correct the common issue of serpentine belt jumping and shredding that was common to those jackshaft-driven S/C kits Vortech produced for the C5 Corvette platform. Most serp. belt issues didn't begin to manifest themselves until the power level and engine RPM capability was increased to where they overloaded the "as delivered" kit offering from Vortech. More engine power, led to additional belt stretch under load, which led to increased belt instability at high RPM, which ultimately led to pre-mature belt failure/jumping/shredding.
*Our supplimental HD Belt Drive Kit corrected that negative issue 100%...
Now, the problem the poster is having is something entirely different than what our kits was engineered for and he's having some of the same problems we also had here when this type of Vortech S/C system was used on very high powered, big block engine's using the T-trim head unit.
In order to create enough boost to feed a big block LSx engine, a higher airflow capacity T-trim head unit must be used and it must be spun very hard to produce that higher boost level to make big power. (10+ lbs.) The combination to do this typically took a large cogged pulley on the jackshaft, (32 or 34, with 34 being as big as could be fitted in there) in tandem use with a small cogged pulley on the S/C head unit. (28 or 30, with 28 being the max. recommended pulley size so blower over-spinning would'nt result)
That S/C set-up requires *A LOT* of torque to spin it at 6000+ RPM to sustain the high boost levels a big block engine like that needs and unfortunely, the little, narrow cogged Gilmer-style belt that drives that S/C is just far too small to support that stress for very long. Combine that with the reduced surface/contact area of that cogged belt that barely wrapped around the small 28-tooth cogged S/C pulley~ you now have the problem of the belt getting the rubber "teeth" stripped right off the underside of the belt, with the outer layer still being intact due to this overload event.
Over the years, we tried every imaginable concept or component to try to combat this cogged belt failure problem, but none of them were really very successful for the long term because the belt was just to small to support the tensile stress of the application....period. Hence, as of a few months ago, we abandoned that S/C design for high powered, big block applications because of that.
The Vortech S/C kit is very well engineered for the C5 Corvette application and performs exceptionally well for stock or nearly stock applications using low (10 psi or lower) boost levels- even with the T-trim head unit. We've comfortably produced 575+ RWHP consistantly without any negative issues what-so-ever on many cars we built here for years.
However, once we crossed that power/cubic inch/RPM threshold to where the little, narrow cogged Gilmer belt was over-stressed for the application, cogged belt durability spiraled downward fast and it was a nightmare to maintain.... Plus, since all the jackshaft bracketry is so tight in fitment, there is no possible way one can fit a wider serpentine -OR- Gilmer belt in that application. Basically, you're effectively "stuck"....
I just don't think that kit was engineered to support that kind of stress loads/power output for those very high powered, big block applications when it was intially designed by Vortech and I suspect that's why they've switched to the A&A and ECS way of conventional S/C head unit mounting on the new kits they offer for the C6 Corvette platform.
Good luck with your project, but at the risk of being called pesimistic, you'll not be able to overcome the durability deficiencies of that design for high-powered applications like you have, unless you re-mount the S/C head unit in a conventional manner like A&A or ECS does.
Been there..tried that...it doesn't work.... (orginal Vortech design described above..)
Regards,
Phil
Our HD Vortech S/C Belt Drive Kit we engineered a couple of years ago was designed to correct the common issue of serpentine belt jumping and shredding that was common to those jackshaft-driven S/C kits Vortech produced for the C5 Corvette platform. Most serp. belt issues didn't begin to manifest themselves until the power level and engine RPM capability was increased to where they overloaded the "as delivered" kit offering from Vortech. More engine power, led to additional belt stretch under load, which led to increased belt instability at high RPM, which ultimately led to pre-mature belt failure/jumping/shredding.
*Our supplimental HD Belt Drive Kit corrected that negative issue 100%...
Now, the problem the poster is having is something entirely different than what our kits was engineered for and he's having some of the same problems we also had here when this type of Vortech S/C system was used on very high powered, big block engine's using the T-trim head unit.
In order to create enough boost to feed a big block LSx engine, a higher airflow capacity T-trim head unit must be used and it must be spun very hard to produce that higher boost level to make big power. (10+ lbs.) The combination to do this typically took a large cogged pulley on the jackshaft, (32 or 34, with 34 being as big as could be fitted in there) in tandem use with a small cogged pulley on the S/C head unit. (28 or 30, with 28 being the max. recommended pulley size so blower over-spinning would'nt result)
That S/C set-up requires *A LOT* of torque to spin it at 6000+ RPM to sustain the high boost levels a big block engine like that needs and unfortunely, the little, narrow cogged Gilmer-style belt that drives that S/C is just far too small to support that stress for very long. Combine that with the reduced surface/contact area of that cogged belt that barely wrapped around the small 28-tooth cogged S/C pulley~ you now have the problem of the belt getting the rubber "teeth" stripped right off the underside of the belt, with the outer layer still being intact due to this overload event.
Over the years, we tried every imaginable concept or component to try to combat this cogged belt failure problem, but none of them were really very successful for the long term because the belt was just to small to support the tensile stress of the application....period. Hence, as of a few months ago, we abandoned that S/C design for high powered, big block applications because of that.
The Vortech S/C kit is very well engineered for the C5 Corvette application and performs exceptionally well for stock or nearly stock applications using low (10 psi or lower) boost levels- even with the T-trim head unit. We've comfortably produced 575+ RWHP consistantly without any negative issues what-so-ever on many cars we built here for years.
However, once we crossed that power/cubic inch/RPM threshold to where the little, narrow cogged Gilmer belt was over-stressed for the application, cogged belt durability spiraled downward fast and it was a nightmare to maintain.... Plus, since all the jackshaft bracketry is so tight in fitment, there is no possible way one can fit a wider serpentine -OR- Gilmer belt in that application. Basically, you're effectively "stuck"....
I just don't think that kit was engineered to support that kind of stress loads/power output for those very high powered, big block applications when it was intially designed by Vortech and I suspect that's why they've switched to the A&A and ECS way of conventional S/C head unit mounting on the new kits they offer for the C6 Corvette platform.
Good luck with your project, but at the risk of being called pesimistic, you'll not be able to overcome the durability deficiencies of that design for high-powered applications like you have, unless you re-mount the S/C head unit in a conventional manner like A&A or ECS does.
Been there..tried that...it doesn't work.... (orginal Vortech design described above..)
Regards,
Phil
Last edited by DTE Powertrain; Jun 12, 2007 at 09:12 PM.
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 1,019
Likes: 4
From: az
A couple of things....
Our HD Vortech S/C Belt Drive Kit we engineered a couple of years ago was designed to correct the common issue of serpentine belt jumping and shredding that was common to those jackshaft-driven S/C kits Vortech produced for the C5 Corvette platform. Most serp. belt issues didn't begin to manifest themselves until the power level and engine RPM capability was increased to where they overloaded the "as delivered" kit offering from Vortech. More engine power, led to additional belt stretch under load, which led to increased belt instability at high RPM, which ultimately led to pre-mature belt failure/jumping/shredding.
*Our supplimental HD Belt Drive Kit corrected that negative issue 100%...
Now, the problem the poster is having is something entirely different than what our kits was engineered for and he's having some of the same problems we also had here when this type of Vortech S/C system was used on very high powered, big block engine's using the T-trim head unit.
In order to create enough boost to feed a big block LSx engine, a higher airflow capacity T-trim head unit must be used and it must be spun very hard to produce that higher boost level to make big power. (10+ lbs.) The combination to do this typically took a large cogged pulley on the jackshaft, (32 or 34, with 34 being as big as could be fitted in there) in tandem use with a small cogged pulley on the S/C head unit. (28 or 30, with 28 being the max. recommended pulley size so blower over-spinning would'nt result)
That S/C set-up requires *A LOT* of torque to spin it at 6000+ RPM to sustain the high boost levels a big block engine like that needs and unfortunely, the little, narrow cogged Gilmer-style belt that drives that S/C is just far too small to support that stress for very long. Combine that with the reduced surface/contact area of that cogged belt that barely wrapped around the small 28-tooth cogged S/C pulley~ you now have the problem of the belt getting the rubber "teeth" stripped right off the underside of the belt, with the outer layer still being intact due to this overload event.
Over the years, we tried every imaginable concept or component to try to combat this cogged belt failure problem, but none of them were really very successful for the long term because the belt was just to small to support the tensile stress of the application....period. Hence, as of a few months ago, we abandoned that S/C design for high powered, big block applications because of that.
The Vortech S/C kit is very well engineered for the C5 Corvette application and performs exceptionally well for stock or nearly stock applications using low (10 psi or lower) boost levels- even with the T-trim head unit. We've comfortably produced 575+ RWHP consistantly without any negative issues what-so-ever on many cars we built here for years.
However, once we crossed that power/cubic inch/RPM threshold to where the little, narrow cogged Gilmer belt was over-stressed for the application, cogged belt durability spiraled downward fast and it was a nightmare to maintain.... Plus, since all the jackshaft bracketry is so tight in fitment, there is no possible way one can fit a wider serpentine -OR- Gilmer belt in that application. Basically, you're effectively "stuck"....
I just don't think that kit was engineered to support that kind of stress loads/power output for those very high powered, big block applications when it was intially designed by Vortech and I suspect that's why they've switched to the A&A and ECS way of conventional S/C head unit mounting on the new kits they offer for the C6 Corvette platform.
Good luck with your project, but at the risk of being called pesimistic, you'll not be able to overcome the durability deficiencies of that design for high-powered applications like you have, unless you re-mount the S/C head unit in a conventional manner like A&A or ECS does.
Been there..tried that...it doesn't work.... (orginal Vortech design described above..)
Regards,
Phil
Our HD Vortech S/C Belt Drive Kit we engineered a couple of years ago was designed to correct the common issue of serpentine belt jumping and shredding that was common to those jackshaft-driven S/C kits Vortech produced for the C5 Corvette platform. Most serp. belt issues didn't begin to manifest themselves until the power level and engine RPM capability was increased to where they overloaded the "as delivered" kit offering from Vortech. More engine power, led to additional belt stretch under load, which led to increased belt instability at high RPM, which ultimately led to pre-mature belt failure/jumping/shredding.
*Our supplimental HD Belt Drive Kit corrected that negative issue 100%...
Now, the problem the poster is having is something entirely different than what our kits was engineered for and he's having some of the same problems we also had here when this type of Vortech S/C system was used on very high powered, big block engine's using the T-trim head unit.
In order to create enough boost to feed a big block LSx engine, a higher airflow capacity T-trim head unit must be used and it must be spun very hard to produce that higher boost level to make big power. (10+ lbs.) The combination to do this typically took a large cogged pulley on the jackshaft, (32 or 34, with 34 being as big as could be fitted in there) in tandem use with a small cogged pulley on the S/C head unit. (28 or 30, with 28 being the max. recommended pulley size so blower over-spinning would'nt result)
That S/C set-up requires *A LOT* of torque to spin it at 6000+ RPM to sustain the high boost levels a big block engine like that needs and unfortunely, the little, narrow cogged Gilmer-style belt that drives that S/C is just far too small to support that stress for very long. Combine that with the reduced surface/contact area of that cogged belt that barely wrapped around the small 28-tooth cogged S/C pulley~ you now have the problem of the belt getting the rubber "teeth" stripped right off the underside of the belt, with the outer layer still being intact due to this overload event.
Over the years, we tried every imaginable concept or component to try to combat this cogged belt failure problem, but none of them were really very successful for the long term because the belt was just to small to support the tensile stress of the application....period. Hence, as of a few months ago, we abandoned that S/C design for high powered, big block applications because of that.
The Vortech S/C kit is very well engineered for the C5 Corvette application and performs exceptionally well for stock or nearly stock applications using low (10 psi or lower) boost levels- even with the T-trim head unit. We've comfortably produced 575+ RWHP consistantly without any negative issues what-so-ever on many cars we built here for years.
However, once we crossed that power/cubic inch/RPM threshold to where the little, narrow cogged Gilmer belt was over-stressed for the application, cogged belt durability spiraled downward fast and it was a nightmare to maintain.... Plus, since all the jackshaft bracketry is so tight in fitment, there is no possible way one can fit a wider serpentine -OR- Gilmer belt in that application. Basically, you're effectively "stuck"....
I just don't think that kit was engineered to support that kind of stress loads/power output for those very high powered, big block applications when it was intially designed by Vortech and I suspect that's why they've switched to the A&A and ECS way of conventional S/C head unit mounting on the new kits they offer for the C6 Corvette platform.
Good luck with your project, but at the risk of being called pesimistic, you'll not be able to overcome the durability deficiencies of that design for high-powered applications like you have, unless you re-mount the S/C head unit in a conventional manner like A&A or ECS does.
Been there..tried that...it doesn't work.... (orginal Vortech design described above..)
Regards,
Phil
Drifting
Joined: Mar 2005
Posts: 1,737
Likes: 0
From: Northern VA
So are you saying a 32/28 pulley combo will work? I had the problems with a 34/26 and 32/24. Right now Gates is looking at the belt to determine what happened to the belt. My issue here is with Vortech. They told me I needed a T Trim blower for this combo and they told me this blower would produce the 10+ pounds of boost I was looking for and they knew I was using the stock brackets and even advised me of where to go to have pulleys made. They knew, or should have known, the limitations of their products and to advise me without this knowledge is irresponsible. As a company they are well aware that their customers are going to want to upgrade. They are all too happy to sell bigger blowers and different pulleys and then when there is a problem they run for the hills like they have no responsibility. The T Trim is not adequate for a 427 CID motor to produce a solid 10+ psi and they knew it had to be over driven to get there. Customers depend on manufacturers for advice and my trust was greatly misplaced in Vortech.
Melting Slicks
Joined: Apr 2005
Posts: 3,418
Likes: 1
From: Chicagoland Area IL
Without knowing your space or clearance constraints, I would look at increasing pulley sizes as much as possible to increase number of belt teeth in engagement. This should help to keep from stripping teeth off.
Also look into European GT3 as Gates US admits it's stronger. If you want PM me and I'll forward info.
Under a steady state load you should not be exceeding belt torque limit even 25 mm wide one. I suspect it's the shock loads in dealing with inertia that is your problem.
Also check for any distortion in brackets as your belt can easily put 800+ lbs of load on shafts.
Mike
Also look into European GT3 as Gates US admits it's stronger. If you want PM me and I'll forward info.
Under a steady state load you should not be exceeding belt torque limit even 25 mm wide one. I suspect it's the shock loads in dealing with inertia that is your problem.
Also check for any distortion in brackets as your belt can easily put 800+ lbs of load on shafts.
Mike
Last edited by Skunkworks; Jun 13, 2007 at 12:42 PM.
