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Can a rear spoiler reduce exhaust fumes?


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#61 olzed

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Posted 18 January 2010 - 08:18 PM

People have been giving the answer to most of the fuming problems :rolleyesg

Seal the vinyl covered panel at the bottom interior of the hatch.!

#62 cygnusx1

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Posted 18 January 2010 - 08:27 PM

People have been giving the answer to most of the fuming problems :rolleyesg

Seal the vinyl covered panel at the bottom interior of the hatch.!


Yes, I have done that. http://forums.hybrid...87&postcount=59

#63 olzed

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Posted 19 January 2010 - 11:36 AM

A lot dont want to believe us.!!

#64 erehemantresni

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Posted 22 January 2010 - 03:32 PM

There is a clear path for fumes to enter the car. Up the "hatch latch hole" and into the cabin through the vinyl panel under the hatch. The vinyl panel is no where near airtight. Remove the vinyl panel, put a bead of sealant around the opening, seal off the opening with a sheet of plastic, reinstall the vinyl panel. This eliminates one more path.


-Does someone have a picture of this?

#65 GeeZ

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Posted 22 January 2010 - 06:30 PM

I found that when the previous owner removed the bumper shocks, he did not seal the bolt holes. The exhaust gases were being sucked in thru these holes.
But that has not taken care of all the gas though.

#66 dennisakon

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Posted 25 January 2010 - 07:56 PM

This has been addressed a couple of times..about a yer ago. Was it Mark(?) who said the rear spoiler did in fact reduce the fumes from entering the rear? Must be a common problem. I get sick from the stuff too. My hatch could use some tightening.
JS


True. A rear spoiler will reduce the fumes from entering the vehicle.

#67 leftover z

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Posted 05 February 2010 - 03:22 PM

I wouldn't think a rear spoiler could help unless you are driving fairly fast. I'm going with making sure the hatch is aligned with a good gasket would be best. Or an ugly-ass tailpipe pointing down to the pavement :burnout:

#68 rusty72

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Posted 04 May 2010 - 10:04 AM

if the rear spoiler is mounted to the hatch and the hatch only i would assume that the bulk of the downforce added would be on the hatch thus sealing it better. that might be why it helps with some and not others it may have very little to do with the spoiler delaying the wake behind the car. people have reported that it helps greatly and also that it doesnt help at all but have not shown how the spoiler was mounted.

just a thought.
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#69 panda-z

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Posted 16 September 2010 - 03:21 PM

i have a spoiler on my 280zx and have no fume problems. it definately creates downforce as the base mounts are starting to bend where they are bolted to the hatch. :)

#70 chris280z

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Posted 20 September 2010 - 04:03 PM

Lots of good info on this thread, I also replaced the seals on my tailight assemblies, the drivers side was jeapordized & definetly allowing fumes to enter. There appears to be several areas of concern back there.....thanks to all for the great info. It's all part of the master plan!
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1977 280z V-8 SBC 5spd Tremec/ in process

#71 Edmund

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Posted 25 November 2010 - 08:09 PM

Odd question, but it comes to mind. I'm thinking adding something to the gas that will make color fumes, like green, red, or something else(I saw this on a drift video before, but for fancy reason) This way, I can at least visible trace where the fumes is coming to the cabin. Does anyone have any experience what I can add to gas produce color exhaust fume without damaging the car? Thanks.

Ed

#72 cygnusx1

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Posted 25 November 2010 - 09:25 PM

Exhaust velocity at the tailpipe might also be at play here.  I find that you get MUCH more stink when driving at part and low throttle.  I think that at high engine loads, the exhaust stream is fast enough to get mostly out past the tail-wake.  When the exhaust is moving slowly, it gets mixed into the tail-wake and swirls around the rear quarter of the car..

#73 hartsel

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Posted 26 August 2011 - 07:40 AM

i just read that book, and realized it was written around 10 years ago. who woulda guessed!

#74 yellowoctupus

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Posted 13 October 2011 - 06:23 PM

So, for anyone who wants to take a shot at the actual vacuum caused at the back of your car, I learned this by simple experience. I was driving my 78 a few years ago, and apparently didn't catch the latch on my back hatch. It was shut, it just didn't 'click'. When I was going 90-110 (it was a few years ago, so I'm not sure exactly what speed it was at) the hatch popped WIDE OPEN. ALL THE WAY. I even have good working OEM gas struts on it still, and it POPPPED right open. So, if you take a force gauge (or put yourself on a scale, and see how much more you 'weigh' when you're opening the hatch lid, then see at what speed your hatch opens, that will tell you how much 'upforce' you have at a certain speed. Comparatively, with the addition of a spoiler, the force to open the hatch may increase with the weight of the spoiler, but the speed at which it opens should hopefully be MUCH greater than it was before. Any takers for a some high speed test runs?

th_280z8.jpg?t=1288666770

Phil - 1978 280z + 4.6L SOHC DOHC Ford, just a 300hp Lincoln Engine Folks, nothing to see here....


#75 Twistedlizard720

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Posted 28 January 2014 - 06:32 AM

One thing I didn't see mentioned was a rear window louvre in terms of the aerodynamics. Would a louvre provide enough edges in the contour to break up the airflow over the hatch? Maybe enough to relieve some of the lift or even eliminate the exhaust fume circulation?

 

My Louvre is currently off because it broke when the car was getting transported. Before that, I never remember having fume issues, but now that it's gone suffer from all the noted symptoms. Once I can source a new louvre that's not a totally ridiculous price, I can post my results.


Edited by Twistedlizard720, 28 January 2014 - 06:33 AM.


#76 RebekahsZ

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Posted 30 January 2014 - 05:53 PM

After you install the spoiler, try installing a modern, fuel injected power plant.  Switching to LS power solved all my hatch fume problems.  And the tailpipe is still in the same place.


1972 240z, purchased in 1991 for $900. Bone stock LS2/T56/DBW from 2006 GTO, swap completed in 2011. 400rwhp/435 rwtq. 2400# minus driver. JCI swap, Mantic ER2 clutch kit, JTR headers, single exhaust, Borla muffler, MGW shifter, M2 Differentials shortened Z31 CV axles, Z31 CLSD R200, Chequered Flag Racing billet stubs and companion flanges. MSD 2-step, Hurst roll control, both operated from switches on clutch pedal. 9" Hoosier drag slicks on Weld Draglites, 245/45/16 Hoosier A6/R6 on 16X8+10 Rota RBR. 225/250 sectioned coilovers, Koni 8610-1437RACE shocks, DP and EMI camber plates, MM shortened rear control arms, TTT front control arms, poly and aluminum bushings. Top speeds: Ohio Mile 174mph, C/GMS class record holder, best 1/8 mile 6.96 at 100mph, best 1/4-mile 11.0 at 126mph, best 60' 1.43, best 1/2-mile 148mph at GA 1/2-mile. Home Track-Jake's Dragway, Moulton, AL. SCCA autocross club - TVR, Huntsville, AL. Lets race!


#77 m1noel

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Posted 30 January 2014 - 06:05 PM

This is a really old thread.  But I can tell you that with the window louvers on, my hatch (if not locked down) will open at exactly 80 mph.   That was before adding the spoiler.  I have tested this with the hatch unlocked since adding the spoiler.  No more opening and losing loose papers all over the interstate.


[SIGPIC][/SIGPIC]Mine-78 280Z,Yellow,GTO LS2/T56- LSD, JCI,headers and radiator from JTR, TONS OF HELP FROM HYBRIDZ, tokico springs and struts, sway bars, Corbeau leather, power mirrors, 18" wheels, AZ brakes and rear LCA's, Wolf Creek CV axles. Hers-05 350Z Grand Touring Roadster, Yellow Pearl, six speed, all options, all stock.
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#78 psdenno

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Posted 30 January 2014 - 06:19 PM

This is a really old thread.  But I can tell you that with the window louvers on, my hatch (if not locked down) will open at exactly 80 mph.   That was before adding the spoiler.  I have tested this with the hatch unlocked since adding the spoiler.  No more opening and losing loose papers all over the interstate.


Added weight of the spoiler at the rear edge of the hatch, or downforce generated by the spoiler, or both?
Dennis
1971 240Z Original Owner

#79 yellowoctupus

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Posted 30 January 2014 - 07:13 PM

 

This is a really old thread.  But I can tell you that with the window louvers on, my hatch (if not locked down) will open at exactly 80 mph.   That was before adding the spoiler.  I have tested this with the hatch unlocked since adding the spoiler.  No more opening and losing loose papers all over the interstate.

 

Ha ha, YES!  I'm glad I'm not the only one this happened to. I don't think I had my louvers on yet, but I have a set on now.  (No noticeable difference.)

 

An interesting thing I found out last year is that if you keep your hatch open about 6" you will get air from the back of the car to flow forwards and out the front windows.  I thought it it was a low pressure zone above/behind the hatch that it would draw air from the front windows, and flow out the back, but apparently there's still MORE low pressure by the front windows (coming off the windshield/front of the car).  I don't have fume issues but it was weird to drive on the highway, have the windows and rear hatch open and have no perceptible air movement inside the car.  The flow is low, but enough to create a high pressure pocket inside the car.  You can put your hand 2-3" past the windows before you feel any turbulence again.


th_280z8.jpg?t=1288666770

Phil - 1978 280z + 4.6L SOHC DOHC Ford, just a 300hp Lincoln Engine Folks, nothing to see here....





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