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Cockpit exhaust fumes

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Detroit solved this problem years ago by shooting the exhaust out to the side parallel with the rear bumper,that way it tangles with the guy in the other lane ;-)Its not hard to do just put a 90deg bend at the end,
 
That might look ok on pickups but I dont see too many cars running that set up, especially all the newer sports cars and sedans---everything is out the back, it looks better out the back, but then like always-- to each his own.
 
shooting the exhaust out to the side parallel with the rear bumper..

Wonder what that would look like?
Have had 2 Mustangs, both GT's. One was a 2000 both pipes pointing straight out the back with the tips pretty much flush with the rear valance-never an odor. The other an '88 with both pipes having downward pointing spigots surrounded and not visible thru the valance-never an odor. The '88 is a hatchback with a spoiler mounted.

•Previous commenters are on to something about the location of those TR6 pipes.
•Previous commenters are on to something about the shape of the 'kammback'.
•Previous commenters are on to something about the sealing of the TR6 trunk.
Love it.

Tosh
 
[ QUOTE ]


•Previous commenters are on to something about the location of those TR6 pipes.
•Previous commenters are on to something about the shape of the 'kammback'.
•Previous commenters are on to something about the sealing of the TR6 trunk.
Love it.

Tosh

[/ QUOTE ]

I turned the trunk weatherstrip around so that the gap was near the fuel filler rather than the lock. Can't say it was much, if any, different. The strip wasn't in new condition but the section along the back seemed to be pretty good and should be sealing OK.

I still don't really understand how you can get so much suction to bring the fumes forward into the cockpit when you're going down the road. But it does seem to smell stronger behind the seats.

Pete
 
Pete,
The "joint" on my seal is at the rear by the latch and the ends are butted tightly.
I would like to see a bit more adjustability in the latch. That is, pull down tighter than it does.
Your comment also brings up a point that has always bothered me about that trunk seal.
Specifically, it just looks pretty skimpy to me. I would like to find a seal that has more "foamy" compressability. Something that will squish tight yet still not interfere with trunk alignment.
Haven't seen that yet but I'm lookin'.

Tosh
 
Tosh, My trunk was a bit harder to close after I turned the seal around. Seems like it should be sealing well enough. I'm not sure what to try next. Pete
 
Heard ya on tha Pete.

Ya know if it were not so cramped and claustrophobia inducing I'd be tempted to crawl in there, get my son to drive down the road @ 60 or so and see if there are spaces that open at speed.
Not gonna happen though.

Tosh
 
You mean your not supposed to reek of exhaust after a drive? I run a Monza exaust on my TR4 and the tipped up tips just make the problem worse. I would think a turn down would help things, or maybe pointing out the side. Didn't TR250 exaust pipes exit at the corner? You could experiment using an elbow and a short length of straight to try both ideas. My next exhaust system will incorperate one or both of these ideas. One other idea would be to try larger sun visors as they probably effect air flow over the car.
 
[ QUOTE ]
You mean your not supposed to reek of exhaust after a drive?

[/ QUOTE ] LOL
Well, I..ah..didn't think so.
As they say in software development .
Fumes?..'it's not a bug it's a feature'.

Incidentally, I drove a TR4 for years back in the 60's and I be damned if recall ever being bothered by exhaust fumes. (Notice I said being bothered by exhaust fumes that doesn't necessarily mean there werent any.)
Back in those days it there was always some kind of smoke goin' up your nose and it was probably hard to differentiate one source from another.
Keep on.
 
Would that it is that simple. How do you know? Please elaborate.

Tosh /ubbthreads/images/graemlins/confused.gif
 
Actually, that is a great point previously unmentioned. The connections could be leaking. If they are, then any other leak will allow exhaust into the cockpit. Even the seal around the trans tunnel.

To get the best seal with the standard U-clamps you need to tighten them, loosen them back up, turn them 90 degrees and then crank'em down again. So make sure your final position is one that allows the most ground clearance.


/ubbthreads/images/graemlins/cheers.gif
 
Swift6; can do that. Thank you.

(The British style clamps make a tightening maneuver such as you describe somewhat of a challenge on those dual/tandem pipes.)
Upon examination there is evidence of blowby @ some of the joints.
What is confounding is that sitting still there are no fumes apparent.
Seems to me, if this is the source, that they'd waft up through the joints when idling at stop.
Yes, no, maybe?
/ubbthreads/images/graemlins/confused.gif
 
Could be a flow/volume issue for that. At idle there might simply not be enough to force it's way past the joints. Air and water flow the same, path of least resistance etc... The back pressure from the muffler at speed could be helping force the exhaust out of the joints. Especially if the internal baffles have begun to collapse in the muffler.

Yeah, the clamps are not that easy to do on the dual but it can be done. It really does make a difference to use that method of clamping.

/ubbthreads/images/graemlins/cheers.gif
 
Okay, first order of business: tighten, loosen, rotate, tighten.
I think I can remember that.
(Would be really nice to do it w/o twisting off the studs.) /ubbthreads/images/graemlins/nonod.gif

tosh
 
Sorry - this thread is back... /ubbthreads/images/graemlins/smile.gif

I stuffed the area around the fuel tank with some foam and bubble wrap, as well as a polythene sheet. I really think it's making a difference in breaking the cockpit suction. There seemed to be strong positive pressure from the trunk into the cockpit when going down the road with the windows open at all. How the fumes are getting in the trunk at all still mystifies me a bit, but maybe the light gaskets are leaking. I found it very difficult to seal it off using poly sheet and tape- hard to find anything to get the tape to stick to properly, plus there are the corners that go over above the wheel arches on each side which are hard to block off.

Pete
 
[ QUOTE ]

What is confounding is that sitting still there are no fumes apparent.
Seems to me, if this is the source, that they'd waft up through the joints when idling at stop.
Yes, no, maybe?
/ubbthreads/images/graemlins/confused.gif

[/ QUOTE ]
So --- Stuff a rag in the tail pipe. Some folks use a potato. /ubbthreads/images/graemlins/grin.gif Then check for leaks in the joints. This should increase the pressure enough to detect leaks at idle.
D
 
Dave,

The presence of leaking joints is not an issue to me, the question is how in the H-E-2xhockey sticks the odor migrates into the cockpit @ speed.

I know that some of the joints are leaking as evidenced by the black carbon streaks on the pipes in that area and that they need tightened...more.

Think I will plug the drain holes in the trunk. These are the only openings that do not have rubber plugs installed.
If blowby fumes under the car are an issue, then those drain openings could be significant.

Best, Tosh
 
Hey Spnr Mn, Don't apologise this has been an hellaciously pregnant thread.

Your observations lead me to think that if I were to fill the area from the taillights to the rear shelf with expanding foam I might lick this problem.

..or maybe not.

Best,

Tosh
 
I think the windshield causes a low pressure in the cockpit, top up or down.... speed makes the differential greater.

I bet side pipes would stop it /ubbthreads/images/graemlins/lol.gif
 
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