Dead Hooking in 4 link dragster

March 05, 2018, 12:30 PM

Having a small issue with a 4 link dragster. When crossing over and also sometimes just at random the car will dead hook and snatch the front tires right out of the bean and throw out a red light. Anyone ever have this issue? Cause of it and what fixed it?

March 05, 2018, 01:41 PM

TORQIN

any weight on the nose?

March 05, 2018, 02:39 PM

TOP38

If the car is consistent then either add weight to the nose or lower the launch rpm or both.

Where is the fuel tank and battery? Two things that could possibly be moved forward instead of adding ballast up front.

March 05, 2018, 04:19 PM

27Keith

I have had that exact thing happen to me. How red and was your 60' and et off ? Adding weight to the nose will fix it, however I was not happy with that answer. We pay a lot of hard earned money for these toys and a builder telling me to add weight to an already heavy car wasn't cutting it. I worked on the shock, 4 link, rpm. One of the big things I have not tried yet that was suggested was to try a different converter.

March 05, 2018, 04:37 PM

TOP38

The converter plays a role in this too but a number of things do, its not just one.

Some builders build their front sections on the stiff side which only make this worse. Some put the tank behind the driver seat and also the battery to far back, all contributing to a light front axe weight which again make this issue worse.

Not sure why anyone would want the fuel tank anywhere near the driver's eat too! But that's me! It should be up front for a number of reasons.

March 06, 2018, 09:33 AM

Peabody Holdaway

Can the suspension be adjusted to prevent this? Just curious

March 06, 2018, 09:38 AM

DragRaceResults

All valid questions and solutions. Yes the suspension can be adjusted to help this also.

Need a little more info on combination.

SL...

March 06, 2018, 11:35 AM

Peabody Holdaway

What suspension adjustments could be made?

March 06, 2018, 11:38 AM

Bucky

Converter would be one area I would point to.
Also, one of the best things I did to my car was move to a physically smaller battery and mount it n the nose of the car. Less battery weight in my case and a bit more weight from cable.

March 06, 2018, 12:24 PM

TOP38

quote:
Originally posted by Peabody Holdaway:
Can the suspension be adjusted to prevent this? Just curious

Nope!

What’s the car weigh on the front axle?

March 06, 2018, 03:33 PM

27Keith

By asking about suspension are you asking about 4 Link setting, shock adjustments, or the spring on the shock ? I believe you can adjust with all of those as well as the convrter.

March 07, 2018, 06:26 AM

Peabody Holdaway

Anything to do with the rear suspension. I don't know anything about the 4 links or the swing-arm cars. I only owned hardtails. I thought by making some adjustments that would solve the problem. Especially if you could change the bars to move the IC?

March 07, 2018, 08:41 AM

TOP38

quote:
Originally posted by Peabody Holdaway:
Anything to do with the rear suspension. I don't know anything about the 4 links or the swing-arm cars. I only owned hardtails. I thought by making some adjustments that would solve the problem. Especially if you could change the bars to move the IC?

Did you not like my answer above?

If you have a dragster that's too light on the nose your swimming up stream if you refuse to add nose weight. You have a few choices but both are basically numbing up the leave. Lower the launch chip and or change the converter. All race cars need to be balanced!

Some chassis are stiffer than others ahead of the driver's foot box, the stiffer ones will have more issues with this also!

Your typical 7.50 dragster needs a good 500 pounds on the nose or you are likely to have this issue, especially when the air and track are good! Hot greasy summer time tracks usually fix this issue also.

March 07, 2018, 10:02 AM

SmokinChicken

Its a 2003 Undercover 4 link. Fuel cell is behind the seat and battery is mid chassis.

March 07, 2018, 11:21 AM

TOP38

quote:
Originally posted by SmokinChicken:
Its a 2003 Undercover 4 link. Fuel cell is behind the seat and battery is mid chassis.

Smoke

Likely your to light up front! The tank that close to the driver is a double no no to me, to close for safety reasons and they need weight up front. Also without a front mount tank, there is all that room to move the battery up front.

Put it on a scale and get the nose weight.

March 07, 2018, 11:44 AM

Peabody Holdaway

quote:
Originally posted by TOP38:
quote:
Originally posted by Peabody Holdaway:
Anything to do with the rear suspension. I don't know anything about the 4 links or the swing-arm cars. I only owned hardtails. I thought by making some adjustments that would solve the problem. Especially if you could change the bars to move the IC?

Did you not like my answer above?

If you have a dragster that's too light on the nose your swimming up stream if you refuse to add nose weight. You have a few choices but both are basically numbing up the leave. Lower the launch chip and or change the converter. All race cars need to be balanced!

Some chassis are stiffer than others ahead of the driver's foot box, the stiffer ones will have more issues with this also!

Your typical 7.50 dragster needs a good 500 pounds on the nose or you are likely to have this issue, especially when the air and track are good! Hot greasy summer time tracks usually fix this issue also.

I didn't say I didn't like your answer. I was answering another gentleman's question. Just curious to learn more about something I know nothing about.

March 07, 2018, 11:50 AM

SmokinChicken

quote:
Originally posted by TOP38:
quote:
Originally posted by SmokinChicken:
Its a 2003 Undercover 4 link. Fuel cell is behind the seat and battery is mid chassis.

Smoke

Likely your to light up front! The tank that close to the driver is a double no no to me, to close for safety reasons and they need weight up front. Also without a front mount tank, there is all that room to move the battery up front.

Put it on a scale and get the nose weight.

Gonna be tuff for me to get that weight up front. I may try playing with launch RPMS etc. Then at the end of the season get other things done.

March 07, 2018, 12:16 PM

Lenny5160

I'd try moving the top bars up a hole in front to soften the hit.

March 07, 2018, 01:08 PM

TOP38

quote:
Originally posted by Lenny5160:
I'd try moving the top bars up a hole in front to soften the hit.

Unless you can get the tires to spin it won't help,,, and you need to make sure they spin all the time or it could be worse.

Been there and have t shirts available for purchase...

March 07, 2018, 01:35 PM

SP 124X

quote:
Originally posted by TOP38:
Put it on a scale and get the nose weight.

Any ideas on a ballpark weight on the front wheels? My hardtail is also fuel cell behind the seat and battery right in front of the foot box. I had 40lbs in the nose and it was all over the place. I ended up pulling the weight and letting it leave wheels up but still not impressed. If I can't make weight work getting an ignition box that will pull timing will be my next move.