I'm Baffled !
Thread Starter
Racer
Joined: Aug 2004
Posts: 410
Likes: 8
From: San Antonio TX
I'm Baffled !
After seeing the new 06 Z07 in BG last May and seeing what Dwight had done to block off two of the outlets on his B&B to reduce the resonance, I decided to fabricate some automatic baffle plates for my 91 ZR-1.
The resonance is much improved at 1800 rpm!
I'm happy to share the info to fab this up.
This setup can either be configured to close the baffles with a decrease in manifold pressure (high vacuum conditions) or reverse the operation and have the baffles open with the secondary throttle plates in the heads. You just have to plumb into the correct vacuum system depending on what you want.
To test the system out I connected the 2 vacuum actuators to a hand pump so I could open or close the baffles while driving under different conditions.
To see any of the installation you have to get really low behind the car.
The vacuum control modules came from Advance Auto Parts # VCD311. These are fully open by 11" of vacuum. The round baffles were cut out of stainless steel with a 2 1/2" hole saw and filed to deburr, then brazed the center hole closed made by the hole saw (map gas torch & brazing rod w/flux). The shaft is 1/4" cadmium plated steel. Too much shaping done on the shaft to use stainless. From the pics, you can see the baffle is notched top and bottom then fitted to a flat spot on the shaft, just like a throttle plate. I covered the shaft with heat shrink tubing to eliminate the metal to metal rattle. The linkage is fabbed up from anything you have. You can even use metal tubing and flatten both ends. I used threaded rod with a threaded coupler.A flat washer brazed on the end of the coupler and one on one end the threaded rod. The top of the shaft has an aluminum bushing with a set screw and a small screw in the top edge to connect the linkage to.
If you have some mechanical abilities and some tools to cut and grind, you can do this.
At some later date I will try to disassemble one side and post pictures of the parts.
The resonance is much improved at 1800 rpm!
I'm happy to share the info to fab this up.
This setup can either be configured to close the baffles with a decrease in manifold pressure (high vacuum conditions) or reverse the operation and have the baffles open with the secondary throttle plates in the heads. You just have to plumb into the correct vacuum system depending on what you want.
To test the system out I connected the 2 vacuum actuators to a hand pump so I could open or close the baffles while driving under different conditions.
To see any of the installation you have to get really low behind the car.
The vacuum control modules came from Advance Auto Parts # VCD311. These are fully open by 11" of vacuum. The round baffles were cut out of stainless steel with a 2 1/2" hole saw and filed to deburr, then brazed the center hole closed made by the hole saw (map gas torch & brazing rod w/flux). The shaft is 1/4" cadmium plated steel. Too much shaping done on the shaft to use stainless. From the pics, you can see the baffle is notched top and bottom then fitted to a flat spot on the shaft, just like a throttle plate. I covered the shaft with heat shrink tubing to eliminate the metal to metal rattle. The linkage is fabbed up from anything you have. You can even use metal tubing and flatten both ends. I used threaded rod with a threaded coupler.A flat washer brazed on the end of the coupler and one on one end the threaded rod. The top of the shaft has an aluminum bushing with a set screw and a small screw in the top edge to connect the linkage to.
If you have some mechanical abilities and some tools to cut and grind, you can do this.
At some later date I will try to disassemble one side and post pictures of the parts.
Last edited by zr1-2go; Jun 23, 2005 at 12:29 AM.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Originally Posted by zr1-2go
After seeing the new 06 Z07 in BG last May and seeing what Dwight had done to block off two of the outlets on his B&B to reduce the resonance, I decided to fabricate some automatic baffle plates for my 91 ZR-1.
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Race Director
Joined: Sep 2004
Posts: 13,793
Likes: 0
From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by cuisinartvette
Wow, nice setup. I was expecting to see some homebrewed thing like a string hooked to a potato or something. You did a clean job 
I was kinda thinking the same thing... that project turned out real nice so when you taking orders 
Thread Starter
Racer
Joined: Aug 2004
Posts: 410
Likes: 8
From: San Antonio TX
Originally Posted by kwik_ta
I was kinda thinking the same thing... that project turned out real nice so when you taking orders Not a huge investment in parts but LOTS of time in making the linkage parts and baffels by hand. I'm not finished with the design yet...still need to make some improvements in a few places.
Thanks for the confidence!
Thread Starter
Racer
Joined: Aug 2004
Posts: 410
Likes: 8
From: San Antonio TX
Originally Posted by Atok
Nice, very nice! Where did you get that front air dam? I kind of like it.
Racer
Joined: Nov 2002
Posts: 478
Likes: 0
From: langhorne
Originally Posted by cuisinartvette
Wow, nice setup. I was expecting to see some homebrewed thing like a string hooked to a potato or something. You did a clean job
Man that is a nice Vette! Love the paint... I guess it's a ZRGS1