Make it handle

[jimmydean]

So no anti squat with a parallel 4 link? How would you account for that in a drag race application? The low CG? I am learning so much cool stuff from this thread.

[robnolimit]

Originally Posted by jimmydean

So no anti squat with a parallel 4 link? How would you account for that in a drag race application? The low CG? I am learning so much cool stuff from this thread.

Yes they run parallel bars, when viewed from the top, but from the side view, they are not. Slicks, and the low CG help. The key is to run the lowest Anti-squat you can, and still hook up hard. Front/rear weight, CG, Tire, it all comes into play.

[Matt R]

So I have a question about the best way to go about gaining more anti squat with the 4 bars. Would it be better to lower the rear mount of the upper bar or raise the front mount of the lower bar? Is it just more of a matter of experimenting with a particular set up?

Matt

[robnolimit]

Originally Posted by Matt R

So I have a question about the best way to go about gaining more anti squat with the 4 bars. Would it be better to lower the rear mount of the upper bar or raise the front mount of the lower bar? Is it just more of a matter of experimenting with a particular set up?

Matt

As a of thumb, try to keep the lower bar near level with the ground. Then adjust the upper bar, or raise or lower the entire lower bar.

[robnolimit]

Wow, not too many comments on the 4-bar/3-link info. Are we still thinking?

[PBFAB.COM]

I have something that could be discussed.... how does the positioning of the link bars at the axle tube come into play? For example, how does the width between the two pivots (side view) effect the function; how does the distance from the axle tube center-line to pivot points (side view) effect its function... etc.

[JNJchev77]

Originally Posted by robnolimit

Wow, not too many comments on the 4-bar/3-link info. Are we still thinking?

Got one.....

Is there a way to properly increase anti squat when running a bagged app, laying frame, with a 4 bar/link? Just wondering how possible that would be with the amount of travel there is in that type of suspension?

[jayman68]

Originally Posted by robnolimit

I know you may hear about the rear 'swing' effect of weight if you move it too far behind the axle. - dont worry about it. Make sure it's safe. With the tank, keep it a bit forward of the rear crossmember, just incase you get into an accident. Move everything you can, every little bit helps. Even think about shifting the motor/trans to the pass side 3/4", for side/side balance. should be a fun driver

Is this to balance for driver weight, weight in the truck, or a combo of both?

[skoffice]

These sites helped me a TON when building my setup. I have a triangulated 4 bar.

Here is the calculator for anti-squat and roll center
http://mysite.verizon.net/triaged/4l...tml/index.html

Here is a great site that helps describe how to get a car to hook up
http://www.baselinesuspensions.com/i...A_Drag_Car.htm

[robnolimit]

Originally Posted by jayman68

Is this to balance for driver weight, weight in the truck, or a combo of both?

Yes, it's to offset weight. Usually there is only the driver. Remeber that the pedals, booster/master, column and wheel are on the right side. Even with the battery, fuel pump, and othe components moved back and left, it's hard to get a balance. Moving the eng/trans helps. - an old MOPAR trick.

[robnolimit]

Originally Posted by skoffice

These sites helped me a TON when building my setup. I have a triangulated 4 bar.

Here is the calculator for anti-squat and roll center
http://mysite.verizon.net/triaged/4l...tml/index.html

Here is a great site that helps describe how to get a car to hook up
http://www.baselinesuspensions.com/i...A_Drag_Car.htm

great info.

[robnolimit]

Originally Posted by JNJchev77

Got one.....

Is there a way to properly increase anti squat when running a bagged app, laying frame, with a 4 bar/link? Just wondering how possible that would be with the amount of travel there is in that type of suspension?

Approach this as a static drop. The only time you really need to focus on the geometry us at Ride Hieght. - you just can't corner that fast with the frame dragging the ground. - lol. Start with the lower bar level at RH, and the upper bar running down hill (in front) appx 5*.

[jimmydean]

Originally Posted by robnolimit

Yes, it's to offset weight. Usually there is only the driver. Remeber that the pedals, booster/master, column and wheel are on the right side. Even with the battery, fuel pump, and othe components moved back and left, it's hard to get a balance. Moving the eng/trans helps. - an old MOPAR trick.

I won't be trying to make it handle THAT well. awesome suggestion though. I can't wait to get this thing together, I am chomping at the bit.

[JNJchev77]

Originally Posted by robnolimit

Approach this as a static drop. The only time you really need to focus on the geometry us at Ride Hieght. - you just can't corner that fast with the frame dragging the ground. - lol. Start with the lower bar level at RH, and the upper bar running down hill (in front) appx 5*.

I'm definitely not a frame dragger and don't like my ride with the nose up lol, just like em low, really low!

[robnolimit]

Originally Posted by porterbuilt

I have something that could be discussed.... how does the positioning of the link bars at the axle tube come into play? For example, how does the width between the two pivots (side view) effect the function; how does the distance from the axle tube center-line to pivot points (side view) effect its function... etc.

Great questions.
First, bar mount width. Side - side. As the rear moves up and down, becuase of the arc of the bar, the axle moves a little bit forward or backward, depending on the bar geometry. Longer bars move less, and shorter bars more. If both tires move up the same amount (suspension compression) the axle moves a bit forward, and stays square to the truck. But, if only one side is compressed, like in a corner or a bump, the rear end can 'steer' itself. As the bar spacing gets closer together, from the top view, the more this 'steering' is noticed.

As far as the pivit point locations go, I think it would be best to have the upper bar pivit point, and the lower bar pivit point be the same distance from the axle center. That being said, most vehicles would have big packaging problems with an upper bar 6" above the axle CL. - This is MHO - no testing. But I can prove this thought. A 4 bar that places the upper bar even with the CL has a lot of issues. Tremendous force is lost as the axle wants to rotate under the bar, instead of a push-pull of the two bars. This tends to let the rear squat, and unload the tires.

[robnolimit]

one of those nights. We went over to A.M.P. (Adams Motorsports Park) last night, even though it was drift night, they let us run the time-attack loop if we show up. We wanted to run the JT with it's wider track set-up. A local guy Kenny B. was there with his S-10. ?? Kenny has been coming in and buying some Afco, Howe, and Speedway parts from us in the last few months. I thought he was building an IMCA Mod, but I guessed wrong. His short bed, std cab is a budget build screamer. Worked over front suspension, read this, build a metric mod front on an S-10, add a big sway bar, and the rear is really simple too. He kept the leafs, added a spring slider to mount the housing (speedway dirt track parts), and added a torque arm. The 4.3 is mildly worked, still EFI, and a 5-speed. Kenny tells us he's at the $3k mark now, and it's a dayly driver. He ran many laps in the 49 sec mark, right along side the JT. Note the S-10 has sticky Falken rubber, 255/45/17 all around. Next he says is a cage, rear sway bar, and adjustable shocks. I'm really sorry I didn't get any picts or video, but we will in the future. He says he'll be at our track day on march 29th. Anyway, a fun and surprising night. It was col to see this home built, well thought out, p/u running good, maybe we can help him get into the Truckin' Throwdown III

[robnolimit]

Oh yeah. The JT ave lap was 49.58, almost .3 sec faster than it's best lap ave. (pev best 49.85). The only change lately has been to widen the track 2" ft/rr. We did this with some billit wheel spacers that we had. Not my favorate way, but we wanted to check it out before we considers a new set of wheels.

[SCOTI]

Originally Posted by robnolimit

Oh yeah. The JT ave lap was 49.58, almost .3 sec faster than it's best lap ave. (pev best 49.85). The only change lately has been to widen the track 2" ft/rr. We did this with some billit wheel spacers that we had. Not my favorate way, but we wanted to check it out before we considers a new set of wheels.

New wheels in the same size but different off-set to increase track width or new wheels that are also wider & thus impacting track width?

[robnolimit]

The current wheels are 9", we may go to 10" all around, with a little less back space, so both gains if we change.

[gofastnut]

I gotta start going to the track on "amateur day", Thunder Hill in Willows, and see what people are running. Hopefully something a little different like the S10 guy, or somebody cool like Rob.

[Grimee]

Hey Rob
have you heard anything about a Throwdown in Ca this year?

[CSGAS]

Originally Posted by robnolimit

one of those nights. We went over to A.M.P. (Adams Motorsports Park) last night, even though it was drift night, they let us run the time-attack loop if we show up. We wanted to run the JT with it's wider track set-up. A local guy Kenny B. was there with his S-10. ?? Kenny has been coming in and buying some Afco, Howe, and Speedway parts from us in the last few months. I thought he was building an IMCA Mod, but I guessed wrong. His short bed, std cab is a budget build screamer. Worked over front suspension, read this, build a metric mod front on an S-10, add a big sway bar, and the rear is really simple too. He kept the leafs, added a spring slider to mount the housing (speedway dirt track parts), and added a torque arm. The 4.3 is mildly worked, still EFI, and a 5-speed. Kenny tells us he's at the $3k mark now, and it's a dayly driver. He ran many laps in the 49 sec mark, right along side the JT. Note the S-10 has sticky Falken rubber, 255/45/17 all around. Next he says is a cage, rear sway bar, and adjustable shocks. I'm really sorry I didn't get any picts or video, but we will in the future. He says he'll be at our track day on march 29th. Anyway, a fun and surprising night. It was col to see this home built, well thought out, p/u running good, maybe we can help him get into the Truckin' Throwdown III

I'd had a few dreams of almost the same formula, just with coilovers and a pair of trailing arms in the rear to go with the torque arm...tell me, did it look like he'd widened or flared at least the front fenders?

I figured if I ever had the chance to really go that route I'd find some of those flared fiberglass fenders for off-road S-10s...the IMCA Metric Mod is based on G-body geometry which is almost identical to the S-10 (parts will bolt on) but a little wider and this idea stayed in the dreaming stage so I don't know by how much.

[robnolimit]

Originally Posted by Grimee

Hey Rob
have you heard anything about a Throwdown in Ca this year?

Yes I have. Thjere will be one. I have the tentative dates, but I don't have the OK to tell everybody. I think by the end of the month, only 10 days, the news will be out.

How's you'r new project comin?

[robnolimit]

Kenny's S-10 has stock fenders, he used wheel offset to cope with the additional width.

[robnolimit]

Looks like GoodGuys is changing the rules for their autocross events. This could be 'Rob Rule #2. From now on, if you win your respective class, like 'truck' you will be moved into the Pro class. The vendor class will be replaced by the Pro class, and all displaying vendors will run in that class. This is to stop guys like me from dominating the class, and giving others a shot at the winners circle. ( I may not like it, but those are the rules now) So, get your trucks ready and get out and have some fun.