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Hackster's LSA / T56 2 door

infront of the axle is **** for these cars

I think what's needed here is an explanation on how to have both ground clearance on the lower coilover mount and enough travel at the same time, and you seem to be holding out on us, Benny.
 
I'm sorry the banter got in the way man, I'm excited to see where this lands though, I'm sure the vast majority of TB has a lot to learn here, and Im sure as hell ready to learn.
 
Forgive the ignorance but is the stock design really so bad for faster lap times? Is there a particular flaw that makes the performance ceiling that low? I can't help but think about the DTM race car, didn't it retain the stock setup? Or perhaps only due to regulations that prevented it from doing the mods that you're looking at?

Either way, stick with it, whatever doesn't work will be a learning experience and you'll be that much better next time around! Go smash around on that sweet yellow prerunner you have and I'm sure you'll be stoked to build the sweetest time attack 242!
 
To answer a few questions these are all just my opinion, not fact.

The ZL1 lid wont fit under the hood by any stretch of the imagination. Also, I am not a fan of the hoses coming right out the front of the engine.

The truck arm is not a very tunable setup and needs to be done with some flexibility in the arms themselves. They are not easy to execute in the aftermarket.

The Factory trailing arm setup / semi triangulated setup is not a bad start, however the front mounted shock, rear mounted coil spring, zero adjustment and soft bushings are all what stopped me from keeping them. They are difficult and complicated to make work with a coilover.


I have consulted with a few friends and discussed my application with them. The general consensus from people who build fast track cars was to add adjustment to the panhard bar mount, and increase the travel of the rear shocks if I could.

Since there is not much if any information out there regarding this I figured I would share what I am doing and why and where I got my information from.

I have taken a few of Ron Suttons classes, they are very good and he is a great reference when it comes to going fast, he understands the limits of working around an existing chassis. He has an immense write up on Lateral G that outlines a lot of what he covers in his classes. If you have a few days to kill read up on it, its an epic write up.

http://lateral-g.net/forums/showthread.php4?t=42423

The idea he promotes is getting the front suspension dialed in with the property geometry and use the rear suspension to tune it for a well balanced car, thus including some adjustment in the rear suspension is key.

Being able to adjust the panhard bar, both height and angle is one of the keys to being able to make the car handle better, it drastically effects the roll center of the chassis and can add or remove grip with just a slight height adjustment. This is after you have the right spring rates, shock valving and all the other things to make a car handle. This is how you make an ok car great, or great car outstanding. You can make it loose, tight or neutral with just these adjustments.

So knowing what I know, I should have ditched the stock panhard bar and mounts before I even started but I got lazy and wanted to move on. Good thing I have some good buddies that said cut that **** out and do it over with an adjustable panhard mount ya jack ass.

I cut off the stock mount and have ordered a slotted style panhard mount for the rear axle, I am hoping it will work well with what I have so far, but am not afraid at all to chop it up.

I will be building my own panhard for the rear of the car, using 1.25" DOM tubing with weld in bungs, 5/8-18 LH for the chassis side, 3/4 RH thread for the axle side. These parts are all commonly available. I am running high misalignment on the chassis side to bush the 5/8" hole down to 1/2" or near the stock size panhard hole. The axle side is just 3/4 bolted on no misalignment needed.

The new panhard will not have a bend in it, will be straight and hopefully allow me to keep the beefed up aluminum moser cover.

So now we move on to getting some more shock travel. Down travel was not going to cut it, so up we go.

After lots and lots of careful measuring and putting this off, I decided to cut into the lower rear framerail of the car and french the shock mount up in the rail. If my calculations were right, this will raise up my shock mount about 1.5".

It was an absolute horrible job on the first side, the second side I took a different approach and it was much more tollerable.

The upper shock mount ended up dead centered front to rear in the rear frame crossmember, this worked good for through bolting through the frame. The first side I did I drilled 4 small holes and connected with a small cutoff wheel, then used a die grinder and deburring bit to open the hole up for the clearance I needed. The second side I located the front edge of the opening and the rear edge of the opening and used a 1.5" hole saw, drilled two holes and used an air saw to get me close, then finished up with the die grinder. It took a fraction of the time.

In case anyone is wanting to do this on their own, the inside of the framerails when cut open measures 1.95", so whatever shock you are going to use, get or build spacers to make your upper shock mount that width, I need to turn a couple spacers still.

I used the same 1.5" hole saw to drill an access hole in the crossmember to access the nuts of the bolt for the shock, this is just big enough to fit a modified wrench up in to tighten the bolt. I do not believe that this hole has any effect on strength of the crossmember.



You can see in this photo that I had to take a little bit off of the bottom of the outside of the framerails in order to give the shock the clearance it needed to swing in all directions and have lots of clearance. I am working off of the garage floor so this is not a fun job by any stretch of the imagination.



So with the access needed, the holes all cut, I wanted to reinforce not only the outside of the frame rail, but also to reinforce the bolt going through the framerail.

So I came up with these guys, I believe it will stiffen up any of the strength I removed and spread the load out on the framerails just fine.





The frame has a slight contour to it so these plates need a little bend in them.

These are just .120 mild steel plates.

Here you can see the clearances I will have, this is more swing than the shock will ever have.







I am going to return the 4.1" travel rear shocks and substitute a 6.1" shock in its place, I will be sticking with the Ride Tech shocks. If you took the time to read through the Ron Sutton write up , it is one of the very few quality shocks built in the US and is totally tunable.

Is this perfect, I am sure its not, is it something I believe I can work around and make fast around a track, I think so.

For those of you that are still reading and want to know what kind of measurements this is. This is built at a ride height of 4.5" to the bottom of the pinch weld on a 25" tall tire, 3" of uptravel and 3" of down travel (Assuming that I dont have to limit the uptravel once its all in the car. Keep in mind with the chocks are behind the axle so actual centerline travel of the rear suspension will be slightly shorter than that.

Brakes for the rearend showed up, backing plate bracket is wrong, so those need to go back but they look awesome.

Hope that parts show up this week to get this all buttoned up, I am so sick of crawling around under the back of this car.

Sean
 
This thread (and especially the above post) is a fantastic addition to the community. Always excited and amazed by your builds.
 
Nice work there! Some old guys taught me to use cardboard to work on or sit in the shop floor. It may not sound like much but if the floor is cold you don't feel it, its easier on your body and if you spill oil on it or gets dirty you can just get another piece. Used to use creepers but like the cardboard better.
Thanks for that link as well.
 
My man!!!! Damn that looks good. I like the reinforcement plates. I'm gonna have to take a look at that thread on lateral g.

It's good to see you back at it, making it look easy as usual :lol:
 
This thread (and especially the above post) is a fantastic addition to the community. Always excited and amazed by your builds.


Thanks, I try to improve on each build I do. I think this is better than the last one =)

Nice work there! Some old guys taught me to use cardboard to work on or sit in the shop floor. It may not sound like much but if the floor is cold you don't feel it, its easier on your body and if you spill oil on it or gets dirty you can just get another piece. Used to use creepers but like the cardboard better.
Thanks for that link as well.

I have buddies that use it, my problem is I dont like clutter, so I get rid of everything I dont need so I dont keep extra stuff kicking around. It definately helps when its cold out. When its hot out the concrete is kind of nice =)

My man!!!! Damn that looks good. I like the reinforcement plates. I'm gonna have to take a look at that thread on lateral g.

It's good to see you back at it, making it look easy as usual :lol:

I am glad it looks easy, cause cutting those holes and making it all look good overhead was a nightmare.

Looks better.

Don't forget to remove the factory shock mount.

Thanks, I had not gotten around to pulling them yet, want to have some way to fill the hole still.

Nice adjustment of the design. Really like the detailed write up. Thanks!

Glad people are finding it handy!!

Been hot up here for the past week and being in the AC business I get super busy. Not much time to work on it this week, need to pickup some tube for the panhard bar, all the rest of the parts showed up yesterday for it. Waiting for the mount still. Rear brakes are wrong so gotta revise that whole situation send them back and get the others ordered.

Car isnt going to be done for LS Fest by a long shot. I thought I would be able to make more progress but its been slow, and its a lot of work. I wont have all my parts in time to get it done.

Good news is I ordered the longer coilovers today, should have them by the weekend so possibly Ill be able to get the rearend in the car, just wont have any brakes on it, can measure for a driveline though at that point.

Hope everyone is having a good week.

Sean
 
Just some input for the thread. I believe your engine is a ly6 variation of the LS engine. also I have a pair of manifolds off Saab with 5.3 and the drivers side is abouts as close as it gets these could possibly clear the steering shaft without modification. Not sure but it's just a guess. Hackster thank you for the thread. I'm about to start my own 240 build as well and you have covered lots of the bases and taken out some guess work
 
Was digging in my magazines and found a Chris Alston catalog. I'm sure you've heard of them. Maybe look at their stuff for some ideas?

They have some great stuff, Helping a friend install one of their cages in a 68 camaro. They more than anything provide me with good ideas than parts to order.

It looks fantastic, let the haters hate! It's probably going to work better then 99.9% of their 240s :)

Haha, true but I still read them with the idea of making me and my build better. Sometimes I wish I didnt give a ****, but I do.

Just some input for the thread. I believe your engine is a ly6 variation of the LS engine. also I have a pair of manifolds off Saab with 5.3 and the drivers side is abouts as close as it gets these could possibly clear the steering shaft without modification. Not sure but it's just a guess. Hackster thank you for the thread. I'm about to start my own 240 build as well and you have covered lots of the bases and taken out some guess work

Yes sir, you are correct, its an ly6. I have not seen the saab manifolds, but they are going to need to hug pretty close to the engine to work. I have an unmodified solid steering shaft installed and about 1/4" of clearance to the Hooker Cast manifolds. Happy to help, glad its useful to someone!!

Post tub pictures! I need inspiration before I start hacking mine up before I get it painted

Dude, I didnt snap any of the progress so far. I have the 10" wheel and the 275 stuffed up in there at this time and it seems to fit pretty well. I have to push the axle back another .25" for clearance to the front but I have room with my adjustable lowers to do exactly that. I need to snap some shots of the work but its anything but pretty at this point and not sure exactly how I am going to patch up the giant hole.

First of all, I ditched the factory panhard bar and mount and ordered one off of the internet. its a single shear style but super beefy and has a .75" bolt through a slotted adjustment hole. This will allow for infinite adjustment of the panhard bar and make tuning much easier in the long run and I dont need to do it over again. This also allowed me to get the mount out from the axle and run a straight panhard bar.

For those following along and wanting to replicate, this is what I am using. .75 x.75" LH Thread Heim Joint (FK) .75 LH Thread weld in bung for 1.25x.120 tubing. .625x.625 (5/8 x 5/8) RH Thread heim joint with .625x.5 High Misalignment bushing and .625 bung for 1.25" x.120 wall tubing This widens the heim to get closer to the stock width. My tube for the track bar ended up at 22.25" long and allows good adjustment to lengthen or shorten for centering the axle.

Dont mind the springs they are too long but you get the idea of what I have going on here.



With that out of the way I could get to the other part I was dreading and that is cutting up the rear fenders for some tire clearances. I did some of the towery method, I marked a line on the outer lip and cut off with the cutoff wheel and separated any remaining spot welds with the air hammer and chisel. Then cut the top a couple inches away from the flange area. Its a ****ty job but it needs to be done.

I then test fit, needed more room. Beat the inner flange a bit, then rolled the outer lip flat. I then put the bottle jack and 2x3 on the inside support and gave her a little push.

What this netted me was 12.25" of rear wheelwell opening between the inner and outer. I have shortened up my lower control arms and thus pulled the wheel and tire forward. It gave me far more clearance at the back near the butt cheek. I dont plan on cutting the metal there as I will be utilizing flares to clear the rest of the tire.

The only pic I took......sorry Ill get more next week.



I had to shut it down though, have a track day on Friday, then goodguys puyallup next weekend so was on Camper, tow rig, trailer, track truck prep for next weekend.



I went from just one beater torn apart to 2 beaters all torn apart, what the hell am I thinking.

It needed a nut and bolt done on it, new front rotors and pads, and a shifter adjustment. Waiting for parts to show up and I should be able to get it loaded up Tuesday night.

Even took it out for a long drive Friday night. Living in the middle of nowhere has its downsides. We drove it just under 200 miles and didnt even make it to a big event, not much going on car wise outside of Portland in Oregon. I sure miss Portland.

Sean
 
That rear setup looks absolutely perfect. And that is a metric **** ton of rear tire. It's gonna look so damn good. And I am gonna shamelessly copy your design.

And that truck is beautiful.
 
That rear setup looks absolutely perfect. And that is a metric **** ton of rear tire. It's gonna look so damn good. And I am gonna shamelessly copy your design.

And that truck is beautiful.

Thanks man, I think it will work. After seeing the 275's stuffed up there I am halfway tempted to run them without cutting the fenders but I totally feel like a sell out if I do. The reason I posted it all up is so that people can copy it, no need for shame at all. If I wanted to keep secrets, well I certainly wouldnt post all this **** up on the internet =)

Pic with the rear tire in the wheel-well - is that full droop or is the rear weight on the jack/rearend?

I have a little over a half inch of uptravel left in this photo, its pretty close to full bump right here. I am beginning to be limited by things like the top of the diff hitting the floor of the car and having the pinion flange be too high at full bump. Without cutting the entire floor and tunnel out of the car, this is about as low as I feel comfortable going. I am still probably going to have to do some trimming.

Sean
 
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