[Jack Gifford]

Tom- Not important questions, just want to know more- after all, when I eventually run them, people may expect me to know a little about them!

Did you pattern them after the original VOE design? I can't recall ever seeing any info on the internals of the originals. Were they originally stainless? Were they put on anything other than GTO's?

Can you dispute/support any of the myths about the short life of the option- "The Feds shut it down", etc.?

Will yours be delivered with a "tiger"-labelled button? (Just kidding!)

Thanks, and keep us posted!

[Tom Hand]

Tom- Not important questions, just want to know more- after all, when I eventually run them, people may expect me to know a little about them!

Jack, anything I can answer, I will. Not many secrets here.

Did you pattern them after the original VOE design? I can't recall ever seeing any info on the internals of the originals. Were they originally stainless? Were they put on anything other than GTO's?

Yes sir, the offset- offset versions are very much patterned after the OEM versions except upgraded with today’s better acoustic materials and methods. They had a few test units on big cars and maybe a Firebird or two or so I heard from some other Pontiac engineers. I have been working with the original inventor and patent holder, Jim Hall. We have been working rather closely on the design and any changes he has suggested, I have tried to incorporate them. Jim said the originals were muffler stainless (409) but were still not resistant to the more corrosive exhaust back then.

Can you dispute/support any of the myths about the short life of the option- "The Feds shut it down", etc.?

They lived from November 1969 until January to March 1970 I have read and heard. All tooling and spares not already in the system were supposedly destroyed. Fixturing and spare parts were removed. Mufflers already in the GM parts system were supposed to have been left. Drawings were supposedly taken out too. A couple of key occurrences were rumored to have stopped this option. Restrictions in PA and some advertising snafus got them banned. Likely as not, the drive by sound was actually checked with them in the open mode. This probably did not go over well.

Will yours be delivered with a "tiger"-labeled button? (Just kidding!)
Ha! Easy to make the decals, hard to make the bracket and switch.

Thanks, and keep us posted!

[Jack Gifford]

Jim Hall of Chapparal (sp?) fame? I watched him start a race at Nuerburgring in '65 or '66. What a contrast of exhaust notes- Jim's bellowing V8 vs. Honda's 16(?) cylinder engine spinning 18,000 RPM or whatever! Also very disappointing that he was out after one lap (I think) with a driveline failure.
Did Jim actually own the VOE patent, or was he contracted to GM, along with patent ownership?

[Tom Hand]

Wrong Jim Jack. Oberg Muffler Co. owned the muffler patent but Jim was the inventor. It expired in 1988.

[Tom Hand]

Well, I have some great news to report. We have the first set on a car, they are running, and they work fabulous. Let me share a few details and then some photos and numbers.
These were redesigned, offset-inlet, center-outlet, 2.5" in and out versions of the stock 70 GTO mufflers. We built them like this to test the offset-center configuration and to retrofit this car (which had prebent pipes to fit offset center).
The car is an original owner, 428 Cobra Jet Torino. Dave had been complaining for years that he wanted noise that he could turn on and off; hence no muffler existed that could provide both levels of sound (other than the VOE-type units). This car is so nice, it was scary to touch.

[Tom Hand]

Now, here are some interesting numbers which will help you all compare sound levels. I tested these on three different cars, my 69 340 Cuda, Dad's 474 Pontiac Wagon and Daves' 428 Cobra Jet Ford, all at 10 feet.

340 Cuda Closed (dBa) Open (dBa)
750 rpm 72 80
2200 rpm 85 93
3500 rpm 93 101

Dad's with his Walker 17749 Dynomax Super Turbos
750 rpm 75
2200 rpm 88
3500 rpm 94

Dad's with VOEs
Closed Open
750 rpm 74 81
2200 rpm 88 96
3500 rpm 95 102
As a reference, the loudest Flowmasters on Dad's wagon run around 101 to 103 dBA at 3500 rpm.

Dave's 428
Closed Open
750 rpm 72 81
2200 rpm 84 93
3500 rpm 89 98


What these numbers show is this: these mufflers provide the best of both "world's of sound" levels. They give you the almost-stock sound of Walker's Super Turbo 17749s in the quiet mode and the bellowing loudness of the chambered-type mufflers when in the loud mode. In Dave's Ford, you can talk and listen to the stock radio and hear only the rear end slightly howl when in the quiet mode. When switched to loud, they resonate and roar and bellow and cackle just like most chambered mufflers do. Really cool to cruise around in for sure!

The drawbacks are that these will not be exceptionally high flowing in the open mode and being stainless steel, and "Hand made", they cost way more than off-the-shelf mufflers. We had no time to air flow test them but I suspect they will be as low as most of the offset-inlet chambered mufflers.

Here are some shots to show the car. It was 20 degrees F and I did not feel like spending too much time driving around looking for perfect spots to shoot photos.

We start the next ones soon for Tom, Jack, Forrest, and Bob. News will be shared as I have it!

[Jack Gifford]

Looking (and sounding!) good, Tom.
So the average sound level increase is around 8 dB, which is a little more than seven times the sound intensity. I assume all those readings are steady engine speed with no load? I would guess that the "loaded" sound difference would be even greater- any feel for that yet?
Got your message, Tom, and I'll call you Monday.

[Tom Hand]

Jack,
Good observation and yes, steady engine speed, no load. It is very hard to consistently load an engine at the speeds we test so we have stuck with static tests. And yes, under load, the loud mode tends to sound much louder but I have no way to verify this objectively as of yet.
The offset-offset versions were about 3 dBA louder on the average when open and that is what I need to discuss with you. I think it would be best to make all of these with the offset-offset configuration to make sure the sound differential justifies the cost. I have already changed all drawings and will be getting with the water jet cutter Monday to start. I think in your case, with the vehicle you have, the offset-offset version can be easily made to work but I want to make sure; that is why the need for the call.

[Jack Gifford]

Tom- I lied! Didn't call you today, because I need to crawl under the truck (which is stored away in the barn) before we talk. I need to look again at whether I would be happy with offset/offset mufflers. No promises as to when it will be- it's been cold enough here to need to bring the brass monkey in at night! Hopefully in the next few days, though.

[Jack Gifford]

Finally eyeballed under the truck tonight. Yeah, there's plenty of room to use offset-inlet/offset-outlet mufflers. Based simply on the spatial layout, my first choice would be center/offset. But if you feel it significantly compromises the design, I'll go with your recommendation Tom.
I'll try to remember to give you a call Thursday.

[Tom Hand]

Jack, I am here, schools are closed, kids are home, 8" snow on the ground!
Tom

[70ra455]

Tom:

Could you PM me on how I can get in on this? I own a '70 455 Ram Air 4spd Convertible that didn't have the VOE option originally (but would have if I was the orignal owner since it was made in November '69.) Original exhuast setup currently but for VOE would make necessary changes.

Let me know either through PM or email at cornellh@ptd.net

Thanks Phil

[70ra455]

Tom:

I haven't forgotten my promise to get one of those switches. I'm still on the hunt and if I can possibly do it I will have one made up. I've already got lot's of input for putting a non-original switch on it but I don't want to have to go the electrical route.

Don't forget to put me down for a set of those mufflers!

[Tom Hand]

Good day all; I want to share another update. We finished two more and have two more in work. Sound tests on the 2.5" in and 2.25" out version mirror those previously fabricated. We see around 8.5-dBA average difference between loud and quiet with quiet being very quiet.
This set should be on its way home to Michigan this week and the next set either to Pontiac Jack soon. Two more pair follow that are the stock VOE sized and then we have one more 2.5" offset offset pair to finish.
Airflow through these is comparable to stock when closed and comparable to the typical "chambered" offset-center muffler when open. This is why I would not really consider them a true "performance" muffler like a Dynomax UltraFlo or Goerlich straight-through version.
Tom

[Tom Hand]

New photos added above.

[70ra455]

Hi Tom:

I'm excited. You still have my name on your list I hope!! (Phil from New Jersey for '70 GTO Convertible so looking for stock sizes and layout.)

And yes I'm still working on switch!

[Tom Hand]

Phil,
I have two ready to remove from the Cuda and strip off the protective wrapping, clean up, and box to send to Pontiac Jack. We have another set of stock-sized ones started for a true VOE car in Iowa. They may be done next week and then we can get on with the last stock-sized set for our patient friend Forrest Fulton .
Please email me; I am contemplating ordering a few more parts to build a set for my Cuda and one for our welder's 88 Blazer and may order a few more parts for folks like you and interested enthusiasts in Michigan.
By the way, I found a new switch and may be able to borrow it and a bracket for photos. Interested?
Tom
thand@kc.rr.com

[Tom Hand]

Got two delivered to New York, safely I might add, and two are on the way to Michigan.

[Jack Gifford]

Wow! They look awesome just lying in my garage!
Can't thank Tom enough.
Only got as far today as hooking MityVac to one, using air hose & blowgun as a sound source, and listening to the different output sounds.

[Tom Vaught]

I too want to thank Tom Hand and his guys for the VOE-II Stainless mufflers sent to me. Very nice pieces.

I may have to try the air hose deal Jack as it will be a few months before the pieces are installed on my car.

Tom V.