70 GTO question

[Belair62]

does a 70 GTO take a different bumper jack than a Lemans ?

[GTO_DON]

No its the same jack. let me know if you need one........

[Belair62]

Yep.....

[GTO_DON]

bob pm me...... http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[Belair62]

What's the correct air cleaner lid diameter for a RA III ? The beat up crappy one on the car is 13 1/4..the one I was sent is a 14 inch unit http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[Mr70]

Who Ya kidding Bob.
It sounds like you are cloning a 70 GTO from a 6Cyl Chevrolet Malibu.This could very well be the longest Topic in sYc History!
Making PopCorn here.... http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

[Seattle Sam]

[ QUOTE ]
Who Ya kidding Bob.
It sounds like you are cloning a 70 GTO from a 6Cyl Chevrolet Malibu.This could very well be the longest Topic in sYc History!
Making PopCorn here.... http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]

Probably wouldn't be such a bad idea, but I heard he's using a '66 Malibu! http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif
-Sam http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[DaJudge]

Bob,
I just measured the original one off my Judge, it is 13 1/4 in diameter. http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[Belair62]

What the heck would I do without you Mike ?! You have answered every single question I have come up with...looks like I got the wrong one...FYI...the RA system is up and running now...column is together and that damn key buzzer works properly now...on to the gas gage and dome light now !among 200 other things.

[Keith Tedford]

Get yourself a GM service manual for the GTO. It has the electrical schematics for the whole car. I just sorted out a birdsnest butcher job in our '69 el Camino and the manual was excellent. We have the manual for our '72 Lemans Sport and it is even better than the Chevy manual for details. Even the wheel codes were listed. I picked up these books at swap meets. Most GM literature vendors seem to have copies.

[Belair62]

Got them Keith....I hate wiring schematics !!!

[Belair62]

OK...saw something in the 70 GTO assembly manual that surprised me...a vacuum operated muffler system ! What the...did this actually get produced ? it opened the baffles in the muffler to reduce backpressure..vacuum diaphrams on each muffler !! Strange set-up.

[MrsBillyBobcat]

Bob,

Only a few early '70 GTO's were fitted with "Vacuum Operated Exhaust" (VOE), before GM put the "kabash" to it. The system used a "tiger button", which resembled a RAM AIR pull knob. When pulled, vacuum went to a solenoid which moved a baffle inside the muffler. The baffle directed exhaust through a lower restriction area of the muffler, which also enhanced the sound. To see the neat application for real, click the link below to watch the 1970 GTO commercial titled "The Humbler", which was also pulled by GM. The VOE and the commercial were too suggestive of racing, so GM dropped them.

The Humbler (http://mypage.bluewin.ch/Pontiac/Download/Commercials/TheHumbler70Gto.wmv)

Rita http://www.yenko.net/ubbthreads/images/graemlins/smile.gif

[Belair62]

Now that would be cool to find NOS huh !!!

[skierkaj]

I'll say, wonder what the prices would be. Ungodly amounts of cash would be able to buy it, but making it last would be another story. That would be a cool thing to find on any car. . . what years did they make that system? Was it only Pontiac, or did the rest of GM have similar systems?

[442w30]

It was available only on the GTO in 1970, and about 250 were made. My friend has one NOS.

[Chris396]

Ha ha those old commercials were so cheesy.

[Mr70]

http://www.yenko.net/ubbthreads/images/graemlins/haha.gif And I wouldn't have it anyother way. http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

[Bill Pritchard]

I remember seeing a feature car in one of the Muscle Car magazines a few years ago that was so equipped. Just incredible the crazy stuff you used to be able to get, although I must say I never heard of it back in the day.

Rita, you get the Gold Star for the day for coming up with the link to that commercial http://www.yenko.net/ubbthreads/images/graemlins/worship.gif http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

[MrsBillyBobcat]

Thanks Bill! http://www.yenko.net/ubbthreads/images/graemlins/wink.gif I thought that was a cool commercial http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif It was filmed here at the "Big Boy" on Woodward.

Rita http://www.yenko.net/ubbthreads/images/graemlins/smile.gif

[DaJudge]

I had the opportunity to buy an NOS VOE set up from Dennis Kirban years ago for about $500.00. I passed on the VOE and got an NOS shifter and wood wheel. The VOE was unavailable with Ram Air and the Judge option, because the actuator button's bracket was similar and mounted in the same place as the Ram Air bracket. Should have ponyed up the cash back then what a cool option to own now.Oh well hind sight is alway 20/20. http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif

[Belair62]

I thought the VOE switch was right next to the Ram Air knob that movie Rita posted...

[DaJudge]

I noticed that as well, but from what I have researched and have been told over the years you could'nt. Maybe that was a prototype car. Who knows but I will check with a few other sources to verify what I have said . Mike

[Belair62]

I put the upper foam seal in the RA pan tonight...very relaxing and enjoyable job http://www.yenko.net/ubbthreads/images/graemlins/rolleyes.gif http://www.yenko.net/ubbthreads/images/graemlins/no.gif

[DaJudge]

You need an extra arm putting in the upper seal and pan. I asked some questions regarding the VOE set up. My info which came from Kirban and sources some 12 -15 years ago may not be correct. I spoke to GTO_Don who asked Jim M about this topic it seems you could get both options together. There is even a RA IV that has the VOE and Ram Air options. It was such a short lived option due to states complaining about noise levels that many people did not know about it. What a killer option to have on a Judge!

http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif

[Belair62]

No..I just put my arm in the microwave and shrunk it to get in there again since I forgot to tighten the darn cable hold down at the flaps !!! Fun !!! I still need a remote mirror....

[DaJudge]

Now I anm confused about the VOE option. Tom Demauro's book quotes John Sawruck as saying that the VOE mufflers when actuated would reposition the baffles from the quite Lemans muffler tone to the more agressive stock GTO tone, and they were not available on Ram Air cars. http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif But if a Ram Air IV car has it listed on it's paperwork somewhere I guess it got installed under the radar. http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[Belair62]

Very cool...I just couldn't believe the diagram on the system in the manual...wow.

[VintageMusclecar]

[ QUOTE ]
Bob,

Only a few early '70 GTO's were fitted with "Vacuum Operated Exhaust" (VOE), before GM put the "kabash" to it. The system used a "tiger button", which resembled a RAM AIR pull knob. When pulled, vacuum went to a solenoid which moved a baffle inside the muffler. The baffle directed exhaust through a lower restriction area of the muffler, which also enhanced the sound. To see the neat application for real, click the link below to watch the 1970 GTO commercial titled "The Humbler", which was also pulled by GM. The VOE and the commercial were too suggestive of racing, so GM dropped them.

The Humbler (http://mypage.bluewin.ch/Pontiac/Download/Commercials/TheHumbler70Gto.wmv)

Rita http://www.yenko.net/ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]

Very, VERY cool, thanks for the link!

Man that thing sounded sweet! http://www.yenko.net/ubbthreads/images/graemlins/burnout.gif

Eric

[Judge Man]

Hi Guys,

I have a few very interesting "Distribution Bulletins" regarding the 611 VOE Exhaust option on the GTO. The option was available on (STANDARD 400 engines only) beginning on October 21,1969. It was discontinued on December 10,1969 for GTO's headed to the State of PA. I have not found the bulletin regarding the availability in other States. I will post these bulletins if I can figure out how to do it. I have no idea how to do an attachment. Mike is correct and did allude to cars "under the radar". As with any Pontiac, you can never say never when it comes to options.

[musclecarz]

I have only seen 2 actual VOE cars and both were GTO's and one was a chrome bumper car, The option was quietly promoted for obvious reasons. There was a vacuum actuator on the rear of each muffler much like the vacuum motor on a Chevelle Cowl flapper, Late in 1969 Pontiac made a TV add that ran during the superbowl, It showed a GTO rolling thru the drive-in, The driver reaches down and pulls the cable under the dash much like the RA cable and the exhaust note picks up and heads turn in the drive-thru!! Very cool, But Alot of people watching the Superbowl were not impressed,Including Pontiac Exec's, and the Monday after the Superbowl was the last day for the rare option. NOS parts for this option are very rare and most of the time must be hand made. I have seen only a few scattered parts NOS through the years and never an actual muffler, There's a repo project for someone!! http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[Tom Hand]

Judge Man,
I am building some new "VOE GTO" mufflers and would love to have copies of anything you might have regarding them. We are building them in other sizes to enable them to work a bit better when open.
Please, if you are still on this site, contact me if you do not mind.
Thank you.
Tom Hand

[Belair62]

Damn...you Pontiac guys are getting the heavy hitters over here..I remember Tom on the Pontiac sites ? Welcome...and that would be an unbelievably cool option to reproduce

[Tom Hand]

Belair62.
They are really cool. Sound slicker than heck too. We have a set on a 69 CJ 428 Torino, a 55 Chevy, and on a OEM GTO 70 VOE car. Two more sets go to real VOE cars, one on another GTO and another on a street rod and the final ones on a Truck.
Very labor intensive to make for sure but cool to have. I can get them together with up to 2.5" in and out where stock was 2" in and 2.25" out.
I have several photos. This set is a one-of-a-kind, offset-center, 2.5" in and out and they are on the Torino.
Tom

[Belair62]

How do these work Tom ?

[442w30]

I wonder which RAIV GTO VOE you speak of? I ask because I know of one and it's a dealer-installed car. I'd be willing to bet this is the same car.

[Tom Hand]

BelAir, they use a former heater/ac vacuum actuator to pull a rod that opens a valve inside the muffler letting the exhaust bypass two of the pass tubes internally. Essentially, it is like running a straight pipe and a very very quiet perf. muffler and being able to switch between them using a vacuum switch.
Tom

[Tom Hand]

And here is a bit of data on how the 2" in, 2.25" out versions worked on my 69 340 Cuda and a shot of the car they are on, a true 70 VOE GTO four speed.

1969, 340 cu. in. 10.5:1 Chrysler engine in Plymouth Barracuda with 2.25” stock, 1969, 340 tailpipes with large rectangle chrome tips, measured at 10 feet from tailpipe outlet.

Closed Open
Idle (700 rpm) 68 dBA 78 dBA
2200 rpm 81.5 dBA 92.5 dBA
3500 rpm 88 dBA 99 dBA

They sound very good.

[Tom Hand]

Belair62, here is a closeup shot of the inlet so you can see the actuator and how it attaches.

[Tom Hand]

And here is the shot of the mufflers from the rear so you can see the spring portion; stand by for one more from the front.
Tom

[Tom Hand]

And here is the last shot showing the overall front configuration... We are currently finishing one more "stock set" and then will build one custom set for a local street rodder. Later this summer, we plan to build a handful more for our own cars and a couple of musclecar enthusiasts.
Tom

[Belair62]

Nice work Tom....any idea of how many VOE cars were sold ???
How does the vacuum actuall hold the valve open on low vacuum situations ?

[Tom Hand]

Official documents show 233 and there were also dealer installed units. I bet the total is less than 270 but that is my guess only.
They have a vacuum can between the manifold's vacuum source and the switch and they have a check valve between the manifold vacuum source and the can. The can is evacuated and then the check valve keeps the engine's loss of vacuum (increase in pressure) from affecting the actuator and letting it go back to normal mode. As long as the can is evacuated and you have no leaks in the system, they stay open. I have pulled a vacuum on these and let them set overnight. The next day, they are still wide open so the system works pretty well.
Tom

[Tom Hand]

We completed another set and here are the sound levels recorded on my 69 340 Cuda.

Closed Open
Idle (700 rpm) 68 dBA 78 dBA
2200 rpm 81 dBA 91 dBA
3500 rpm 88 dBA 99 dBA

This set will be installed on one of the true VOE 1970 GTO's still left.