My question is that what kind of power gains do you get from exhaust cut outs. Do you even really gain power or do you lose power from the cut outs. I'm looking to put some on, but want to know if their worth the time and money. If not it when be worth the money to hear open exhaust easiler.

Thanks

It depends on how restrictive your exhaust system is, and where the cutouts are placed.

In my '87 Iroc with 2 1/2" pipes from the headers, to a mandrel 3" single pipe all the way back through the muffler... I put a cutout in where the catalytic would be about 3ft behind the passenger side bank... I gained 12HP with the cutout open.

If your exhaust is not restrictive, it's more for fun. But it's GREAT FUN. I recommened getting one of these: http://www.mccordcg.com/mpp/mpp.htm

It's an electric cutout plate. Instead of uncapping the cutout, you just flip a switch on the fly.

I agree, I have the same electic cutouts on my chevelle and they are awesome!

There are too many variables to say whether opening the exhaust ahead of the mufflers would increase power or not.

The exhaust can be tuned to compliment your engine, but it's way over my head. Vizard has some interesting writings on this. He calls it "5-cycle" engine tuning or something like that.

It would be cool to uncap the headers on the fly, but I don't know what it would do for performance. Even if it would increase the horsepower a tad, would it be enough to overcome the extra weight you just added?

The electric cutout mod reminds me of the GTO option around '70 with the under-dash knob you pulled that I believe eliminated the resonators. I remember a very cool TV commercial back then that showed this.

It's worth .25-.3 on my ETs, so they work for me! I've got them after my H-pipe, and boy does it sound good!

Cutouts are just a few extra inches of pipe vs the pipe that was there before. Couple bolts and a cap, doesn't weigh much at all! Even the electric plates don't weigh much at all.

High said MAYBE 20-30lbs added to the car?

Sounds good so far (in more ways than one).

I don't race, so the cool factor would be enough for me. graemlins/thumbsup.gif

I had the old cable controlled "Y" pipes on a '69 Dodge Polara (383) when I was a teenager. They leaked and the car sounded horrible until I pulled the cables. :D (Probably still sounded horrible)

I even had an air compressor and air shocks that I robbed from a junked Olds F-85. I used to crank up the compressor and slowly pull the cables as the rearend rose up. The things kids do for fun. :D

bruce, the pontiac GTO option you're talking about is called the "VOE" option, offered for a short time in 1970. it consisted of a vacuum diaphram on each muffler, that, when a cable was pulled under the dash, would route engine vacuum to the canisters, and open up an express route straight through the mufflers.

Pontiac put out a commercial during the super bowl that year showing a VOE equipped GTO pulling into a drive in and kicking the pipes open. as soon as Pontiac suits saw the commercial, they took it off the air, and cancelled the option, leaving just a few cars already on the road with this rare option.

It is worht 3/10s on my truck...I have 2 1/2"str8 pipes with flowmaster 40s with turn downs

Originally posted by marinablue67:
bruce, the pontiac GTO option your'e talking about is called the "VOE" option, offered for a short time in 1970. it consisted of a vacuum diaphram on each muffler, that, when a cable was pulled under the dash, would route engine vaccum to the canisters, and open up an express route straight through the mufflers.

Pontiac put out a commercial during the super bowl that year showing a VOE equipped GTO pulling into a drive in and kicking the pipes open. as soon as Pontiac suits saw the commercial, they took it off the air, and cancelled the option, leaving just a few cars already on the road with this rare option. Yep, there were approxamatley 223 of these cars built with the VOE option.

Regarding the "VOE" option on the GTO, does anyone know if the letters represent anything, or similar to an RPO# ?

Just guessing. Something like "Vacuum Opened Exhaust"?

Probably "Vacuum Operated Exaust"

yep, that's it.

Correct me if I'm wrong, but, it sounds like there are a couple people here saying that they have dual? 2 1/2" exhaust pipes and? running the cut outs??? If so, then are they running one or two exhaust cut outs?

If you have dual exhaust, you need two cutouts....

if you have exhaust that collects to one single pipe, then just get one places behind the Y.