Different Torsion Bar Keys

[bigmileage]

Well I'm in the process of finally buying a Ty, reading through the forums more now than before.

I was quickly looking at lowering and noticed the many discrepancies in torsion bar keys that have been discussed on here. Here's a link to what we discussed over on S10forum with part numbers and degree differences in the keys.

http://www.s10forum.com/forum/f220/torsion-keys-how-many-different-stock-ones-are-there-485380/

Just in case the link dies I'll list the quick details.

Consolidated and moved , will update as needed.

Key colors and part#

#15684327 (Blue)
#15684328 (Yellow)
#15712480 (Orange)
#? (White)


Part Number Bar Dia. NOM Torque
LH 15956501 26.63mm(1.05") 1052
RH 15956502 26.63mm(1.05") 1052
LH 15956503 27.94mm(1.10") 1276
RH 15956504 27.94mm(1.10") 1276
LH 15956505 29.36mm(1.16") 1450
RH 15956506 29.36mm(1.16") 1646
LH 15956509 30.69mm(1.21") 1883 <--ZR2/Z85
RH 15956510 30.69mm(1.21") 1883 <--ZR2/Z85
LH 15956511 32.51mm(1.28") 2305 <---ZR2
RH 15956512 32.51mm(1.28") 2305 <---ZR2


apparently, the GM keys are all made from the same
CASTING #, 15530030, then machined to their index angle, color coded, and assigned the below part #'s:

GM Part # Angle Color Code
15045171 4 DEGREES PURPLE
15657374 9 DEGREES BLUE
15603963 12 DEGREES ORANGE
15592573 14 DEGREES GREEN
15592574 18 DEGREES WHITE

and the Ford keys are somewhere
above the GM "white" keys in index
angle from what I gather...

Changing keys - dependent upon which key your truck has and bar size (6 different bars) - would make lowering more comfortable and possibly more drastic as well.

 

[bigmileage]

Re: Different Torsion Bar Keys

Stock SyTy's have about 3" of suspension travel. A: A 3" drop is about as "drastic" as possible without cutting stuff up. B: When the suspension hits the stop, the ride becomes decidedly less "comfortable".

Increasing the spring-rate allows the same amount of jounce energy to be absorbed in less travel. I feel this is the key to retaining some semblance of "comfort" in a SyTy that is "drastically" lowered. But I have yet to see any reports on here where someone figured this out and tried it.

My point was just that, why has nobody tried the key with less degree index and a stiffer bar. There are/were about 6 "standard" bars on S/T trucks, with about 30 different variations.

Drastic being used in the sense that one could get the drop they wanted while still having a better than usual (i.e., standard drop with constant bump contact) ride due to key and bar changes.

In a standard 4wd - on several occasions - I've been able to change bars/keys to achieve similar lift while having totally different ride characteristics. Typically the less stiff bar (not the huge ZM6 bar) with a higher degree key has the best lift with the best travel/ride. it would seem a more stiff bar than stock and the lowest degree key (4*) would achieve the best ride/drop (opposite of a lift setup).

Thanks for posting that info, after all that searching I never found that.