4 Link System - Step by Step

[Jeff 4100]

Jeff, if the extra weight you're carrying is ballast you've added to gain more traction then yes, taking it out might slow the car down.

Yes Mike!! It was placed there just to gain more traction!

How much weight have you added for ballast? Is it 100#? Have you tried only 50# of ballast since the other changes you've made?

It is almost 140 pounds. No, I never tested my car with less ballast yet...But, look my car weight without the ballast:
LF=670
RF=740
RR=584 (!!!!!!)
LR=729
Without the ballast, I don't know what I can do to solve that big weight difference on the RR wheel...
Help me!!!

All these things need to be figured out during testing on the track. Do you have any opportunity to test the car without being in competition?

No. We'll be disassembly the engine...I think I won't have a time to test before the race...

I'll let you discuss the preload issue with Billy if that's a strategy you wish to try. I think there are less complicated methods you haven't explored.

Ok Mike. I'd just like to hear your opinion about it...I haven't my car scale yet...and without it I can't test the Bill's suggestions...

Getting the car's weight reduced, tire pressure changes, gear ratios, increasing front suspension travel, and improving weight bias will give you good results.

Yes! These changes will be my way for the next race...

Posting some very clear photos of the tire tracks left on the track could give us some idea of what might be needed.

Ok! I'll run behind it!!

Thanks!!

[Mike Peters]

How much weight have you added for ballast? Is it 100#? Have you tried only 50# of ballast since the other changes you've made?

It is almost 140 pounds. No, I never tested my car with less ballast yet...But, look my car weight without the ballast:
LF=670
RF=740
RR=584 (!!!!!!)
LR=729
Without the ballast, I don't know what I can do to solve that big weight difference on the RR wheel...
Help me!!!

The large weight difference could be caused by preload in the suspension links or a spring that is in a bind. Make sure all your suspension components have freedom of movement the next time you weigh the car. Adjust all the links and make them loose so you can easily turn them by hand before putting it back on the scales. Make sure you tighten them when you are done.

Posting some very clear photos of the tire tracks left on the track could give us some idea of what might be needed.

Ok! I'll run behind it!!

Thanks!!

Funny Jeff!!! I see you've caught on to our humor!!!

[BillyShope]

LF=670
RF=740
RR=584 (!!!!!!)
LR=729

You've got a lot of what the oval track racers call "positive cross." I can't remember: Do you have adjustable coilovers? If so, the above can be quickly changed to:

LF=742.5
RF=667.5
RR=LR=656.5

If you don't have the adjustable coilovers, you can still get these numbers, but it means a whole lot more work.

This is assuming, of course, that you even want equal rear tire loading statically, which would only be the case if you have some means of dynamically canceling the driveshaft torque's tendency to unload the right rear.
http://www.racetec.cc/shope

[Jeff 4100]

The large weight difference could be caused by preload in the suspension links or a spring that is in a bind. Make sure all your suspension components have freedom of movement the next time you weigh the car. Adjust all the links and make them loose so you can easily turn them by hand before putting it back on the scales. Make sure you tighten them when you are done.

Unfortunately, my car scale won't arrive until the next race...
But, I'll try to lend one of it during the weekend of the race...

Funny Jeff!!! I see you've caught on to our humor!!!

I'm very happy to be understandable for you...
Next year I wanna be there...so, I need to adapt for my new friends!!!


Thanks!!

[Mike Peters]

Unfortunately, my car scale won't arrive until the next race...
But, I'll try to lend one of it during the weekend of the race...

Jeff, you've done very well in making improvements. The scales should give you several clues in making some more improvements. In the meantime, I think you mentioned your next race is December 10th, correct? I know you're anxious to make as many improvements as possible but, sometimes it's better to understand how much each improvement has gained. Don't change so many things that you don't understand how much gain each improvement made. I am going to be very curious what the increased compression will do for your performance.

Next year I wanna be there...so, I need to adapt for my new friends!!!
Thanks!!

Let us know when you're coming up here Jeff. That would be great!!!

[Jeff 4100]

I think you mentioned your next race is December 10th, correct?

Yes!!!

I am going to be very curious what the increased compression will do for your performance.

Me too, my friend!!!

Let us know when you're coming up here Jeff. That would be great!!!

MIke, I wanna go there in my next vacations...I think it would be at june or august...
I'd like to do the Dave Morgan's Seminary, watch a Drag race and visit as much friends as possible...what do you suggest for me there in Kansas??

Regards!!!

[Jeff 4100]

What I was getting at was that there is a reaction to every force or torque. The driveshaft torque tends to unload the right rear tire. The reaction to that driveshaft torque is taken at the engine/transmission mounts. From there, it is absorbed into the chassis and reappears as deflections in the front and rear suspensions.

Mike/ Bill,
How is the way that you use the engine movement to get more weight transfer??
I'm asking it because I have my engine totally stopped over the mounts...the engine doesn't move when it is turning (like an original engine does over the original mounts)...the engine is wrapped!

How do you fix your engine into your car?? Do you use rubber mounts?? Does the engine work free and its movement you can see easily??

I don't know If I made me clear...I wanna know if the engine needs to be free and its movement is important to the weight transfer...
Thanks,

[Jeff 4100]

I know you're anxious to make as many improvements as possible but, sometimes it's better to understand how much each improvement has gained. Don't change so many things that you don't understand how much gain each improvement made.

Mike,
Let's talk about my shocks...Look my current setup:
LF - 80/20
RF - 60/40
LR-RR - 90/10

What do you think?? I'm running with this setup since 2 races ago...

Thanks,

[BillyShope]

How is the way that you use the engine movement to get more weight transfer??

You can't. The height of the engine (from the track surface) never changes, so the car's center of gravity height doesn't change, so weight transfer is not affected.
http://www.racetec.cc/shope

[Mike Peters]

Mike,
Let's talk about my shocks...Look my current setup:
LF - 80/20
RF - 60/40
LR-RR - 90/10

What do you think?? I'm running with this setup since 2 races ago...

Thanks,

I'm puzzled as this is not the normal set-up for shock installation. You have 90/10 shocks on the rear of the vehicle? This is the first time I think I've ever heard of someone installing that shock valving on the rear of the car. Also, if you do have 60/40 valving on the right front of the car, you are giving up some weight transfer capability as that valving would be too stiff for allowing the front of the car to rise during launch. The 90/10 valving shocks need to be on the front and shocks like 60/40 or 50/50 should be on the rear of the car.

[Mike Peters]

How is the way that you use the engine movement to get more weight transfer??
I'm asking it because I have my engine totally stopped over the mounts...the engine doesn't move when it is turning (like an original engine does over the original mounts)...the engine is wrapped!

How do you fix your engine into your car?? Do you use rubber mounts?? Does the engine work free and its movement you can see easily??

I don't know If I made me clear...I wanna know if the engine needs to be free and its movement is important to the weight transfer...
Thanks,

Keep the engine solidly mounted as you currently have it. You do not want the engine to move freely. The force transfer Billy is describing is transmitted through solid engine mounting. If the engine was able to move on rubber mounts, it would not direct it's energy through the chassis as well.

[Mike Peters]

what do you suggest for me there in Kansas??

Regards!!!

That may be the hardest question you've asked Jeff. Not much here in Kansas to visit. Not that we wouldn't want to see you but, if I were you, I would plan my vacation around a big race like Orlando or the SCSN race in Las Vegas where there is also some other great attractions to see. Orlando has all kinds of things to see in addition to a big race and so does Las Vegas. I think it's great you want to visit us but, Kansas is not known for a great vacation spot for people coming to the U.S. Just something to think about.......

[BillyShope]

The force transfer Billy is describing is transmitted through solid engine mounting.

I was including rubber mounts. Rubber or solid, the height of the engine's center of gravity does not change.
http://www.racetec.cc/shope

[Mike Peters]

I was including rubber mounts. Rubber or solid, the height of the engine's center of gravity does not change.

Billy,

I'm trying to explain this so Jeff can understand. He's a sharp guy but, sometimes has a bit of trouble in translations. He's asking if he should switch to rubber engine mounts because he thought you were suggesting engine movement improved weight transfer and he should, therefore, switch to a pliable substance for engine mounting. Please don't pick apart my statements to Jeff for minor technicalities and trust that I know the engine's C/G wouldn't change regardless of engine mount material (even toasted marshmallow). Jeff asks me (off the board) to translate your posts as he's trying to learn all he can. I do the best I can with the time that I have without trying to complicate things even further.

[BillyShope]

...he thought you were suggesting engine movement improved weight transfer....

Sorry. Didn't realize he misunderstood me.
http://www.racetec.cc/shope