Club Cobra - trimming the header pipe

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trimming the header pipe

Hello all,
I am fitting the side pipes and trimming the headers a bit to get them up and under the car correctly. How close can I come to under edge of the fiberglass body before I set the car on fire? I was told only a finger of spacing was needed. How much are the pipes hanging below the boxed frame if you view from front to back. Thanks mike

Quote:

Originally Posted by 289ERAkit (Post 1213013)

A finger is plenty. And both sides don't have to be the same. Remember, only the driver's side is going to torque over.

http://www.clubcobra.com/photopost/d...0/pipes003.jpg

http://www.clubcobra.com/photopost/d...0/pipes002.jpg

http://www.clubcobra.com/photopost/d...0/pipes001.jpg

Would it be different with an ERA 289 model? I thought the header pipes came together at a collector inside the fender and then exited underneath the fender instead of through a cutout, like the 427 model does?

...but, what do I know, I'm just an ERA owner wannabe, never been close to one of their 289 models, only drooled all over myself as I look at the photos on ERA's website (almost daily, though!!)...

Cheers!

Dugly :cool:

So long as you get them so they just look right, I don't think it really matters. Here's the pic that they use for the FIA comp pipes and the back hanger. I'd just hook it all up, stand back from it, eyeball it, and if it looks good and you can get a finger between the pipes and the glass, leave it alone.:cool:

http://www.clubcobra.com/photopost/d...rearhangar.jpg

Hi Mike, I'd recommend 3/4" min to about 1". Make sure the timing is set, I've seen them scorch a good paint job from slipped timing. Yes his is an under car FIA exhaust, how's it coming together Mike?

My FIA has stainless pipes that are not aligned with the body. The distance from the collector to the bend is too long. I will be taking it in for alignment soon.

My thought was to cut the expanded collar off of the side pipe and work the side pipe into the proper position and re-weld the collar back on to the side pipe such that the pipe is parallel to the body.

Is it correct to shorten the collector? - would make it a lot easier - seems un-natural.

Quote:

Originally Posted by ERA2076 (Post 1213095)

Is this on the passenger side? My 427 street roadster with ERA undercar exhaust headers suffered the same problem on that side. My theory (?) is that the fabricator is not taking into account that the motor is offset 1 inch to the passenger side - thus the pipe ends up extended out too far and too near the body rocker panel area. If its on the driver side then my theory is shot.

I carefully marked mine for up/down and had it put in a pipe bending machine and bent 2 deg (roughly and it now fits fine). However, it now has a typical slightly curshed profile on the inside from the pipe bender that I hate. Not visible except from underneath but still there.

A better solution is to cut the pipe where it joins the 4-pipe collector, carefully grind the pipe until you have the angle and clearance corrected, mark index points on the pipe/collector, pull it off and lightly tack weld it and test fit it before pulling it off and finishing the weld. You may not even need to cut the pipe completely loose 360 deg. If you just need a 1/2 inch or so of movement you can probably leave a half inch or so at the front uncut as a hinge and to keep everything jigged up correctly. The when the metal is cut out this may give you enough movement to line it up and re-weld it.

By the way - if you trim the engine header pipes to move the collector and headpipe in a 1/2 inch, you will also raise the level of the headpipe by 1/2 inch since the exhaust come off the engine at about a 45 deg angle.

Have you checked to make sure the engine is dead level in the chassis? If it's rotated even slightly, that gets magnified way out there at the end of the exhaust head pipe.

http://www.cobracountry.com/cobra4sa...b-1332x686.jpg

DanEc - above you can see. I am not sure we can just trim the pipe. I am concerned with this much mis-match that the pipe will move too much in the horizontal plane. In other words if we trim it and get it to the right height, I may have pulled the pipe to far in board with respect to the exhaust end. That is why I am thinking more difficult cutting and welding may have to be done. We will try trimming first. Both sides of the car are the same. I have not checked the engine for level - I will.

x-chr

DanEC - Here you can see the mismatch. Unfortunately they are aligned axially along the body pretty well. As you eluded we cannot just shorten the head pipe as it will pull the pipe in board with respect to the exhaust end. I have a good exhaust specialty shop close by. Am going to have them take a look. I have seen some CSX cars that look like this.

http://www.cobracountry.com/cobra4sa...b-1332x686.jpg

I like this.

http://www.cobracars.be/_wp_generated/wp2e0cf7bb_0f.jpg

Hi,
Sorry.... i went missing over the weekend.
Yes the engine is level and I have trimmed away what I believe is the right amount and seems to be a fat finger away from the fiberglass body edge. I ended up using a $10 harbor freight cut off air tool and removing the spark shield. The pipes are 3" and the cut off disk is 3" so I took an old exhaust pipe and hacked on it till the cut off wheel was somthing less that 3". Then.... took a quater inch off at a time working from inside the header. I'll post pic's next week of how I laid the pipes out while on the lift next week.

I had a local guy peek at this job and he was concerned of the body's lower fiberglass edge catching fire, so...I thought it a good point to question. If your headers clunk the body under acceleration.... you should probably fix it. I guess the correct timing will keep the pipes from becoming cherry hot ..? Good point not to mess with the timing too much. All else is going well...
Thanks for your input. mike