C4 dragging
Thread Starter
Heel & Toe
Joined: Mar 2011
Posts: 15
Likes: 0
C4 dragging
Love the C4, one question though - when I go over speed bumps, many times I scrape something on the bottom of the car. I have not looked to see what scrapes as of yet. Does anyone know, on C4's (mine is an '86 roadster), what exactly is the lowest thing hanging down under there that will scrape first - just trying to determine if its something to worry about or not. Thinking maybe it could be the exhaust system/resonator hanging down at lowest point. Not sure though. Thanks.
Race Director
Joined: Oct 2005
Posts: 11,770
Likes: 175
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
Most C4's will do that if the speed bump is very high.
You don't have a lot of ground clearance to begin with.
And your roadster has a cross brace under the car, that probably hangs down just a tad more.
Best option is to go really slow, and hit move at a slight angle.
I'll still hear a slight scrape sometimes though.
You don't have a lot of ground clearance to begin with.
And your roadster has a cross brace under the car, that probably hangs down just a tad more.
Best option is to go really slow, and hit move at a slight angle.
I'll still hear a slight scrape sometimes though.
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
However looking under my car I found an after market exhaust hanger bolt was my culprit over the long speed humps. Get the car up in the air and look underneath. The scrape points will become obvious.
Le Mans Master
Joined: Dec 2005
Posts: 5,198
Likes: 10
From: Homestead Fl
St. Jude Donor '06-'07-'10-'11-'12-'13-'14
My X brace is banged up from speed bumps on my 91. I developed a rattle when I shift in reverse. Just a little tap,tap, tap that wasn't there until I hit a couple of speedbumps. I don't even like to drive my cars to visit my mother because of the sharp curb angles going into her complex and the monstorous speedbumps they put in the throughways. It's a freakin bang fest (with low cars) where she lives.
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
My X brace is banged up from speed bumps on my 91. I developed a rattle when I shift in reverse. Just a little tap,tap, tap that wasn't there until I hit a couple of speedbumps. I don't even like to drive my cars to visit my mother because of the sharp curb angles going into her complex and the monstorous speedbumps they put in the throughways. It's a freakin bang fest (with low cars) where she lives.
It's happening worldwide,believe me !
Drifting
Joined: Aug 2009
Posts: 1,971
Likes: 243
I go over a dozen speed bumps each time I leave/arrive (condo complex).
Two things help, one I go as slow as possible over them, and two I hit them at an angle rather than straight on.
But, all too often I bottom out. And worse of all, it is the ZF6 that takes the hit! When I last changed the engine oil I also took the time to pull a few small chunks of speed bump asphault off the lowest point at the front of the trans.
Two things help, one I go as slow as possible over them, and two I hit them at an angle rather than straight on.
But, all too often I bottom out. And worse of all, it is the ZF6 that takes the hit! When I last changed the engine oil I also took the time to pull a few small chunks of speed bump asphault off the lowest point at the front of the trans.
Pro
Joined: Jul 2006
Posts: 635
Likes: 1
Unless you drive a convert. and have the x brace the most likely thing to hit is the skid frame between engine cross member and radiator support. I'm mounting wheels in this area as my car is lowered and will be even lower than stock. If you don't want to go to that much trouble It would be pretty easy to mount thin plastic pieces where it hits. That would protect the two areas it drags on. Mine was almost worn to the point of having holes in metal and that was from when it was at stock ride height.
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