Bumps Suck - what to do about them?

[John_Heard]

Lost 2nd round yesterday, car unloaded again in the right lane at MoKan at the transition bump. I should have softened the shocks up more I guess.

Looking for ideas and suggestions at what to do about down track bumps - what do you do? I've been softening both bump and rebound, that hurts the 60' but helps with bumps but doesn't seem to ever be enough. I can take power out with a gear retard at that spot, haven't tried that yet, but might help some?

Any other ideas? Does a spoiler help? More rear percentage? Would like to fix it without taking power out or tight fitting dots... To much to ask?

Bump is at 175' out or so, right after the 1-2 shift.

[aitch o]

1st - loosen the suspension
2nd - pull out 3-4 degrees timing for 1/2 second over that period.
your car will be faster like that vs. riding the dots.

[8secpumpgas]

Try and drive around them

[supernova]

I think I would work on the front end set up and leave the rear alone. loosen the compressure on the front shock so it floats over the bump. More times then not the front end will upset the chassis and cause the back to unload.
When you travel over the bump at speed it may seem like the rear is the only thing that gets upset. But the front hit the bump first. Think about it, If your car has the front end on the stops and the shocks are tight it will upset the chassis and translate the hit of the bump to the rear end as it hits the bump.

Leave the power and rear end alone and try the front first. Soften it up!

Just my thinking.

[bracketracer]

go in the left lane

We had a bump in our left lane a few years back. My car always seemed to loose .015
of et so I just dialed up.......... ... I just was not comfortable with messing with
anything on the suspension as in the late rounds you just don't have time to anything but
put some gas in it.............

[John_Heard]

I guess bump isn't really a correct description, it's a drop off in that lane where it goes from Concrete to Asphalt

Looks kinda the picture below with the black line being the concrete and the gray the asphalt - Chris you don't have problems with that spot in the track? If you're driving around it are you going closer to the guardrail or centerline?

transistion.jpg (2.65 KiB) Viewed 9102 times

[supernova]

Hi John,
The track I run at has now been revamped to all concrete.
So not much of a problem now. But before it was fixed it did upset some of the faster car
Than mine. I talked in length with a good friend before posting ( he has been tojust about every suspinsion school out there even Dave Morgan's.
Now with that said, we came to a point in conersation that mycar set simular to yours
Will act in the manner. We decided that looking at how the whole Car setup could be the key to the fix when hitting bumps or drop offs in the track. I know that Kents car had the same
Problem and to fix it he had to losen the front shocks and give more room to travel.
Now that my car going together talking about how to fix this kind track problem, I will look at the front and back and see if that are working together. Sometime it's not back that is the issue.

[John_Heard]

I don't have a lot of travel in the front end with the current setup, so yes it might be helpful to loosen the front end up also - good point and I'll keep that in mind.

[supernova]

sorry for the bad typing. I'm doing it on my Iphone.

[vegaracer]

I would pull timing out at that spot if you could. And a wing may help.

[wikd69]

I would pull timing out at that spot if you could. And a wing may help.

Maybe toss in a drumstick while you're at it. That could help.

[ERV JR]

Bitch til they fix the track

[Dave Morgan]

John,
I'd agree with the guys who suggest more and softer travel in the front shocks. At 175 feet, I doubt you're going fast enough to need a wing.
ST
Dave

[John_Heard]

No I doubt a wing would show much improvement if any at that point on the track, I was really thinking of downtrack where it's also spinning. If a wing generated even 20 lbs less lift on the back at the bump point I'm sure that would help some though.