Cutouts

[69clone]

Hey guys,
I'm thinking about throwing some cutouts on my car for when i'm messing around with friends or at the track. I've heard the electric ones can rust up, Plus there like 400 bucks and i really don't wanna spend that kind of money. So i'm leaning towards the lever kind that way i don't have to worry about getting dirty and can easily change to open headers at a redlight when that fart can pulls up next to me. So i'm just wondering if anyone uses any kind of cutouts? Are they hard to install?
Btw I know it's illegal and i can get a ticket but for the most part i think cops around here are decent, at least when it comes to classics, i see pro street cars driving around town every now and then with open headers.

 

[69 Runner]

While it might sound cool to have open exhaust, you realize you could hurt the performance of your car by not having enough backpressure.

 

[khryslerkid]

Just place them a foot or so back from the flange and you'll have enough resistance. You just use them for a short anyway. It's called having fun! I remember running into town with open headers when I was a kid. Made it kinda hard to hear the radio but you got a lot of attention.

 

[69 Runner]

Sure. Back in the day I had Mickey Thompson "Power Y" headers (the longest headers on the planet) on my runner, and I occasionally opened them up. But it screwed with the jetting and wouldn't run at WOT unless I went to a really cold plug.

You have fun with that

 

[69clone]

Thanks 69runner I understand it won't build pressure but if I get them I'd only be using them to p off my friends, when someone asks me to start it up lol or like kid said driving through town.

 

[Meep-Meep]

In my experience cutouts or opening up the headers always made more power at high RPM.

In the 80's with my 383 I had the typical $75.00 system that used turn downs right before the rear axle. What I did was cut the exhaust pipe right past the rear torsion bar anchors and welded a coupling to one end of the pipe to form a slip fit. The system was secured with springs for street driving and the cross over held the individual pipes together when I uncorked it. I'd go to the track, undo the springs and give the pies a kick to pop them loose and off I went. I ran a piece of light duty chain along the seat bolts and that held the pipes up so they didn't hit the ground.

When I put in the Max Wedge using the same 1-3/4" headers and exhaust from the 383 the system would un-cap itself at the top of 2nd gear!! Scared the crap out of me the first time it happened but I felt a surge in power when it came loose. After a while it got pretty funny street racing with automatic back pressure operated cutouts! Back pressure is bad, but what's more important is a proper length pipe to put the pulsating exhaust in resonance with the target RPM. Just like tuned intakes exhaust follows a similar rule and the window of opportunity is about 1000 RPM. Cutouts are a long way from ideal exhaust tuning but if they relieve some restriction they are not a bad thing.

If you have Flowmasters supposedly they don't detract from performance and from what I have read they add to it. Dunno, but I have 3" Flows on my 66 and it seems pretty happy. In that case rattle some windows in the fart can cars!

 

[69clone]

In my experience cutouts or opening up the headers always made more power at high RPM.

In the 80's with my 383 I had the typical $75.00 system that used turn downs right before the rear axle. What I did was cut the exhaust pipe right past the rear torsion bar anchors and welded a coupling to one end of the pipe to form a slip fit. The system was secured with springs for street driving and the cross over held the individual pipes together when I uncorked it. I'd go to the track, undo the springs and give the pies a kick to pop them loose and off I went. I ran a piece of light duty chain along the seat bolts and that held the pipes up so they didn't hit the ground.

When I put in the Max Wedge using the same 1-3/4" headers and exhaust from the 383 the system would un-cap itself at the top of 2nd gear!! Scared the crap out of me the first time it happened but I felt a surge in power when it came loose. After a while it got pretty funny street racing with automatic back pressure operated cutouts! Back pressure is bad, but what's more important is a proper length pipe to put the pulsating exhaust in resonance with the target RPM. Just like tuned intakes exhaust follows a similar rule and the window of opportunity is about 1000 RPM. Cutouts are a long way from ideal exhaust tuning but if they relieve some restriction they are not a bad thing.

If you have Flowmasters supposedly they don't detract from performance and from what I have read they add to it. Dunno, but I have 3" Flows on my 66 and it seems pretty happy. In that case rattle some windows in the fart can cars!

Thanks Meep-Meep,
Yeah i don't have flowmasters, Not sure the size of my headers but they run to 2.5" exhaust into cherry bombs... I'm not really worried about any proformance gain or loss it's just going to be for fun, But of course i'd like to see if it makes a difference in the 1/4. I was wanting to put the cutouts around the door area so if i do open them on the road i can really hear it LOL.

EDIT: Anyone know where i can find a 2.5" manual lever cutout? I only found 2"...

 

[MarPar]

I ran a piece of light duty chain along the seat bolts and that held the pipes up so they didn't hit the ground.

Sorry to hijack the thread, 69. :eusa_whistle:

But i was wondering if there was any other way other than chains, to hold the pipes firm to da car. Cuz when i jam on the loud pedal, you can hear the pipes thump on the bottom of the floorboards. :3gears:

 

[69 Runner]

chains????????????

If your exhaust is mounted properly end to end, it won't bang on anything when you hit the loud pedal

 

[Dennis H]

QTP's. Quick Time Performance. They have been on for years and are absolutely trouble free. Nothing beats a rolling smoky burnout with them open.

 

[Meep-Meep]

Sorry to hijack the thread, 69. :eusa_whistle:

But i was wondering if there was any other way other than chains, to hold the pipes firm to da car. Cuz when i jam on the loud pedal, you can hear the pipes thump on the bottom of the floorboards. :3gears:

If your pipes thump the floor there is not enough room to allow for slight movement, or your motor mounts are spongy causing too much movement. The chains were only to hold the front half of the system when I pulled it apart from the header end otherwise they were just dangling :icon_hang: It was a quick and easy solution and had nothing to do with holding the system in place under normal conditions. For that I had springs!!