Thread: and one for the math wizards.....

Tweet

I've been going over a lot of old build sheets and track performance records trying to figure out some correlation for rear 4 bar length as it relates to engine set back and wheelbase.... I've been through all my books and they all say pretty much the same thing, mainly emphasizing the angle of the bar, especially the upper bar, and how the bar angle and wheelbase effect lift and weight transfer working off the centerline of the car....

I'm trying to come up with some kind of formula that would take into account the centerline, instant center, wheelbase, % of engine setback, and bar length and angle.... Or am I just looking for data that isn't there?????

PS, if you're wondering what to get me for Christmas, a data acquistion system sure would be nice!!!!!

Dave, I don't know if it's in here somewhere because I have not read all of it, but if not, at least it will keep you busy for a couple of weeks....
http://home.earthlink.net/~whshope/
http://www.hotrodders.com/kb/suspens...ering-articles
http://www.hotrodders.com/kb/suspens...ing-articles-2
http://www.hotrodders.com/kb/suspens...ing-articles-3
http://www.hotrodders.com/kb/suspens...ing-articles-4
http://www.hotrodders.com/kb/suspens...ing-articles-5
http://www.hotrodders.com/kb/suspens...ing-articles-6
http://www.hotrodders.com/kb/suspens...ing-articles-7
http://www.hotrodders.com/kb/suspens...-steering-tech

well what i did was mark all my bar mounting points for my rear end and frame mounting points laid them out on the shop floor and run them thru till they came to gether and seen were they hit .i mark out were the wheel base was and were the engine sat and i found out were i wanted to put the new mounting holes for better hook this may not be what you want but it work for me. i am lifting about center of the oil pan now were before it was just in back of the drive set know it hooks alot better then ever

Thanks Tech, you always come through for me!!!!!! Don't really know what I'm looking for actually, just charting some things and want to see if there is some fact to back it up or if I'm seeing things!!!!!!

Wow, lots of great stuff in there, I guess Insomnia isn't all bad, huh????

Looks like I have a bit of searching and reading to do!

The best one is probably Billy Shopes homepage. I just added it at the top.

Originally Posted by pat mccarthy

well what i did was mark all my bar mounting points for my rear end and frame mounting points laid them out on the shop floor and run them thru till they came to gether and seen were they hit .i mark out were the wheel base was and were the engine sat and i found out were i wanted to put the new mounting holes for better hook this may not be what you want but it work for me. i am lifting about center of the oil pan now were before it was just in back of the drive set know it hooks alot better then ever

Yeah, kind of what I'm after... I keep diligent records on the cars I build. The ones that get raced I keep track of, too. Whether Steve and I own them or they are built for some of the racers we know. Anyway, after all the different combinations I've tried, trying to bring all the performance data together and see if I can form some sort of logical pattern as to what different bar lengths and angles do when matched up with engine setbacks and wheelbases. Hopefully, I can establish some kind of baseline and see not only what combinations work, but why they work.... I like to do the research stuff, and occasionally it leads to some facts that a casual observation may not bring to light..... I've still got the build sheets and track performance data from a '56 Ford with a CAE straight axle that my Dad and I built when I was in high school.......though not a lot of that data is relevant today.....

Originally Posted by techinspector1

The best one is probably Billy Shopes homepage. I just added it at the top.

I think you gave me that one other time Tech, ????? Somebody sent it to me anyway. Needed it again though. My old computer crashed and I no longer had the link for it..... Thanks again!

Just as a side note, Billy was one of the original Ramchargers!!!!!!!!!
http://www.hotrodders.com/forum/members/billyshope.html

Really? I sure didn't know that!!!!

At coffee Friday we were talking, sure wish the "Over the Hill Gang" name wasn't already taken!!!!! I'm 57 and the rest of the group calls me "kid". Our average age is 63!!!!! I guess we'll have to settle for being the local version of it!!!!

Originally Posted by pat mccarthy

well what i did was mark all my bar mounting points for my rear end and frame mounting points laid them out on the shop floor and run them thru till they came to gether and seen were they hit .i mark out were the wheel base was and were the engine sat and i found out were i wanted to put the new mounting holes for better hook this may not be what you want but it work for me. i am lifting about center of the oil pan now were before it was just in back of the drive set know it hooks alot better then ever

Exactly Pat, here's the way Billy explains it.......
"In the side view, visualize a horizontal line through the center of gravity (about camshaft height) and a vertical line through the front tire patch. Then, a line...called the "no squat/no rise line"...passing through the intersection of these two lines and the rear tire patch.

Finally, visualize lines passing through the centerlines of your links. There will be an upper line (through the upper two links) and a lower line (through the lower two links). If you don't want the car to squat or rise, arrange the links so that the intersection of the upper line and the lower line falls on the no squat/no rise line. If you want it to rise, put the intersection above the line; squat, below the line."