Cowl Shake

[Russ Dickey]

Guys, I did a search on cowl shake and didn't find anything, so I thought I'd place a new post. Can you guys define for me exactly what cowl shake is? I think I've got a pretty good idea, but I just want to make sure.

When going over some really bumpy roads, my Cobra gets a slight shudder in the cowl area (between the back of the hood and the windsheild). It's not real bad, but it's enough to make the hood shake side-to-side enough that it's worn down the paint where the hood meets the inner lip on the fender. Is this cowl shake?

If so, how do I stop it? I've adjusted my hood latches and made them tighter, and that seems to help keep the hood still, but now when going over a bumpy road, the hood latches work themselves around into the unlatched position. Anybody got any ideas???

Thanks and Happy Holidays to all!!

Russ

Unique 289FIA - Viking Blue

[WBofTN]

Russ:
I put 2 rubber bushings on top of the latch prongs. I then adjusted the
latches to make a snug fit. Also, these bushing are handy for driving
with your hood slightly open (just lay down the hood w/ the latches in the closed position). This will drop you engine temp 5 degrees or
so in heavy traffic by letting the heat out.
WB

'93 Unique 427/351W/4sp

[GeorgiaSnake]

Russ
Cowl shake is generally caused by lack of rigidity. The car is twisting along the longitudinal axis. The only way to lessen it is to increase the rigidity of the frame. The bodies of our cars offer little or no rigidity as they are simply bolted in a few places. Increasing the attachment points would do little, as the body is basically a shell and not a structural member.

I have thought about bonding the doors to the body and additional points to the frame but think that would increase the likelihood of creating stress points and cracks. I avoid the bumps to keep the shake down.

Randy


Unique 289 FIA
Southern Automotive 396
Team III 16's
Brilliant Silver

[Okiesnake]

Like Wes, I added rubber stops that I made from rubber stopper plugs. I actually added 4 - two at the top and one on each side. You can custom fit them to length with a dremmel cutting wheel. I glued them in place and also inserted a small sheet metal screw from underneath the channel and into each stopper.

[clayfoushee]

If you don't already have them, you should consider lockable hood latches. I learned early on that they will work themselves loose eventually, thus I now keep mine locked when driving the car.

Clay

Unique 9299, 427FE side oiler, top-loader (close), 3.31 rear

Annapolis, MD

[Brent]

Lets face it. A 500HP fiberglass car driven on the street will shake. Doors will rub,hoods will shake,gauges will flutter,and heads will turn. Just another day in a Cobra!!!!


Brent

[Tony Radford]

In my case, I determined that a lot of the rattling sound came from the attachment point of the long rod that holds the hood open. I mounted a spring to one of the existing bolts on the driver's side foot box. Chill inserted some bushings and quieted his that way.

427SC, Torch Red / white stripes
427 Windsor Stroker from Southern Automotive
Delicious example of Beauty + Power.