 
     |
| Northstar 6 Speed (Page 4/20) |
|
Zac88GT
|
OCT 05, 12:29 AM
|
|
|
Well i take 1 step forward and ten steps back. i bolted on my struts/spindles today to double check my calculated measurement for axle length and low and behold, the axles don't F***ING line up. A crutial measurement that i assumed to be the same was the distance from the input shaft to the axle splines, this turns out to be different. So now i have to redo all of the engine mounts and make a new dogbone to move the engine back 1 inch. I sure hope theres room in the engine bay for that it was pretty tight before. I'm sooo pissed right now.
|
|
|
|
Zac88GT
|
OCT 05, 01:22 AM
|
|
|
On second thought, moving the engine back 1 inch would require all new engine mounts, new dogbone, possible interference with the power steering pump pulley and strut tower, possible interference between rear head and firewall, I am making new headers anyway but the old ones would not line up anymore. I would also have to make a new cold air intake tube, and the decklid strut would probably cause an issue as well. Basically everything i did to get the northstar in there originally would have to be changed and i'm not prepared to do that much grinding, welding and fabrication all over again. With the shortest axle being probably somewhere around 10" between pivots and a 1" offset thats less that 6* equivelant steering angle. I've decided i'll just let the cv axle take up the angle since i dont think 6* is to big of a deal. If the cv wears out a little quicker than if it were straight, big deal, it's a hell of a lot easier to change one of those every 5-10 years than remaking everything.
|
|
|
|
fieroguru
|
OCT 05, 07:20 AM
|
|
Some will say that the axles need to be perfectly aligned, but I tend to disagree. Your 1" offset to the front is the same as if someone lowered their car 1". With all the lowered Fieros running around, there has not been a huge rash of CV failures on the lowered cars. Not all CV's are created equally, but the front axles on a chevy 4x4 run at a significantly greater angle than 6 degrees from factory.
What is the distance from the crank centerline to the center of the front cradle bolt? My halfshafts are also at an angle to the front, the car is lowered about an inch, and the engine is lowered within the chassis, so my halfshafts could be at a slightly larger angle (never measured it), but they have been that way behind a SBC for 20,000 miles without any issues (and 5K of that was puliing a 1000 lb trailer).
|
|
|
|
Joseph Upson
|
OCT 05, 07:23 AM
|
|
| quote | Originally posted by Zac88GT:
Well i take 1 step forward and ten steps back. i bolted on my struts/spindles today to double check my calculated measurement for axle length and low and behold, the axles don't F***ING line up. A crutial measurement that i assumed to be the same was the distance from the input shaft to the axle splines, this turns out to be different. So now i have to redo all of the engine mounts and make a new dogbone to move the engine back 1 inch. I sure hope theres room in the engine bay for that it was pretty tight before. I'm sooo pissed right now. |
|
Sorry to hear that, I know the feeling when it isn't right and there is no option aside from cutting and welding after you've done so much of it already. I used the shift cable from the 4 spd muncie from advance auto on my 6 speed, I didn't know of any other options used on the Fiero that had the proper ball cup size. Is there no way you can cut the mounts in two and weld them back together offset?
|
|
|
|
Zac88GT
|
OCT 05, 11:04 AM
|
|
Modding the tranny mounts for an inch backwards wouldn't be that bad but the engine mounts would be trouble, ecspecially the frame part of the rear engine mount because of where it is and the shape of it.
Plus the engine would have to be raised for the oil pan and tranny to clear the suspension mounts. The more i think about it the less concerned i'm becoming, I think it will turn out allright. Joseph, i used 2 getrag 5 speed select cables, proper cup size and they're quite long so they're not an issue routing around the bohemouth N*. When i had the 5spd tranny in there the select cable was fine but the shift cable had to be re-routed to go through the original select cable hole in the firewall to get it closer to the tranny. It was a real tight fit over the top of the head and onto the 5 speed. But with two select cables and the different bracket geometry it should be great. I'd like to see the difference in length between one of the cables you used and one that i used.
|
|
|
|
HTXtremes
|
OCT 07, 08:08 PM
|
|
|
|
|
Zac88GT
|
OCT 10, 10:27 AM
|
|
I have the axles ready to attach somehow. I will post the exact lengths once they're together and i know they'll work. I'm not sure how i'm going to put them together yet. They are about a .005" press fit into a 1/4" wall hydraulic tubing sleeve. The tubing itself should be strong enough considering that torsional strength increases to the 4th power with radius. I figure that even with the metal compositions being different the tubing should transmit 2-3 times more torque before breaking than the solid 1" axles. I'd like to try and not distrub the temper in the axles, they are hardened about 1/4" deep as you can see in the pictures. I'm not sure if i should press them together and rely on the friction fit to transmit the torque or press them together and weld them at both ends. If i just rely on the friction and then do spin then they might spin weld in place and could become stronger than just a bead around the outer edge. I'll have to look more into this and start another thread about spin/inertial welding and friction fits.
|
|
|
|
darkhorizon
|
OCT 10, 11:47 AM
|
|
There have been a few that have tried welding axle shafts in the past, and they never followed up on their results. This most likely means that they succeeded, but I would like to see that its a proven method, as it is significantly easier trying to get axles in these 6speeds.
Edit, Would it be possible to get some splines cut into both the "tube" and the axles? Instead of a pressed juncture, why not have a pressed, splined, welded juncture?[This message has been edited by darkhorizon (edited 10-10-2007).]
|
|
|
|
fieroguru
|
OCT 10, 02:39 PM
|
|
You could drill a couple of holes in the sleeve, assemble the axles and then plug weld the axle to the sleeve to ensure they do not spin. The press fit would help lessen the torque the welds and area around the welds would experience.
|
|
|
|
Zac88GT
|
OCT 10, 08:18 PM
|
|
| quote | Originally posted by darkhorizon:
Edit, Would it be possible to get some splines cut into both the "tube" and the axles? Instead of a pressed juncture, why not have a pressed, splined, welded juncture?
|
|
A spline would be the best in this situation, but if machining a spline was a possibility than i would have just cut the shaft to the right length and remachined the spline for the inner tripot assembly. Unfortunatly this whole process is to get around the machining of splines. (i dont mean to sound sarcastic or anything, that truly would be the best way to attach the collar) I have a feeling that i'll end up welding them, but if i do i will be sure to document the abuse that i put them through  and if they hold up.
|
|
|
|