[QUOTE=deuce_454;269182]

i dont agree that moving the trailingarms will affect the hit of the car like moving the arem on a 4 link.. and the reason fro this is that the trailing arms mount to the uprights and they do not absorb any of the forces involved in turning the wheels.. that reaction is handled by the longitudinal arm mounted to the diff case... the trailing arms only handle thrust from the wheels on acceleration and enginebraking, and the rotational forces excerted when applying the brakes..

I do agree that you don't alter the tire loading effects caused by the rotational forces of the rear end by moving the front of the IRS 4-link, but you do change the instant center of the rear suspension. This alters the percentage of loading caused by mass of the vehicle on the rear tires during acceleration. Some circle track cars use this principle (moving the 4-link pick-up) to load the outside rear tire during acceleration. Most use a full floating rear end which, in effect, stops the rotational forces from transfering through the four link, much like an IRS.

Pappy

[QUOTE=mfain;269225]

Quote:

Originally Posted by deuce_454 (Post 269182) i dont agree that moving the trailingarms will affect the hit of the car like moving the arem on a 4 link.. and the reason fro this is that the trailing arms mount to the uprights and they do not absorb any of the forces involved in turning the wheels.. that reaction is handled by the longitudinal arm mounted to the diff case... the trailing arms only handle thrust from the wheels on acceleration and enginebraking, and the rotational forces excerted when applying the brakes..

exactly.. so its only the "lift" caused by "pushing" on a non horizontal pair of links.... so the antisquat effect is caused by the thrust acting over or under the C or G..

Well I'm only in the thought process of my build right now so I'll proly change my mind several times.

If you need a point of reference go here:

http://www.stevesnovasite.com/forums...64#post1299964

Jasons already grafted a C4 front end onto his '63.....

John

Recently used this setup on a 58 vette with C4 rear transplant. Very easy to install. Didn't cost much either. Tray Walden is owner.

http://www.streetshopinc.com/c4str8axl.html

that is not a really well engineered package... its nice, but for a lateral-g car that gets beat on and driven... i wouldnt trust a shop that solidmounted the pinion like that.. and relied on the shockmounts for springs and bumpstop...

the corvette spindle isnt designed to carry the weight on the shockmount... and how on earth can you use a solid mount on the pinion of the diff case, when the rest is rubbermounted ??

the ladder connecting the tranny and rear end on a c4 isnt there to impede the exhaust, but to transfer the torque from the pinion...

a quick calculation... engine tq:500, 1.gear ratio:3.07, rear ratio:3.33 => wheeltourque:5111 ft/lbs... distance from pinion support to axle~1foot.. => load on frint x member in first gear 5111 lbs...
with the corvette ladder arrangement the distance is closer to 5 feet, and the resulting load is ~1000 pounds, wich is fine for a double sheer mount 3/8 inch bolt in a rubber bushing...

if the tube is a 40x3mm steeltube the moment of resistance is 1178, and the press is 5111 lbs = 22.7kN assuming the length of the x member is 1m the moment is 11.3kN/m the stress in the tube at that point is 9650n/mm2 = 1400ksi.. :willy:

this means that the first time you get traction in first .. it will bend as you are far beyond the yield strength of weldable steel

if you were to do the same with a cantilevered spring or airbagged controllarm to cary the load where the spindle/upright is designed to ttansfer load... and some longitudinal controllarm to transfer the torque... youd be fine..

but doing an IRS install requires alittle grey matter activity

(alot of the street rod stuff out there simply isnt safe.. well its fine for a trailerqueen, but much of it is in the words of ralph nader "unsafe at any speed")

Great info Deuce - Thx much !

Jim

I've got a C4 Dana 44 rolling around the shop - for like 5 years now - after listening to Deuce -- it's no wonder I've never stuck it under anything!! :rofl: :rofl:

after doing the math.. im all fired up about installing one.. care to sell me yours ? :D

I'll start crating her up! It even has the 3:42 gears...

I'm serious - I've been pushing it around here for 4 or more years now and I'm not going to use it. My new chassis for the 37 has a Ford 9".. and leaf springs... Low tech at it's finest. :rofl: