Drop Spindle Discussion

[BigSwede]

Quote:

Originally Posted by nizam It obvious he had drop spindles (just trying to swing it back from OT)

[Grant]

Copied from alfagtv6.com/bb

http://alfagtv6.com/bb/viewtopic.php...a1bc35b9e8ba2c

"No need; Potenziato from the alfabb was kind enough to copy a page from a shankle catalog as well as swap spindles with me (he has RSR coilovers and wanted to get rid of his drop spindles, b/c they put the coilovers out of their range of adjustment).

So after many hours under the car, and with a 9 foot long pole, I was able to twist my 27mm torsion bars enough to remove the A-arm bolts (I think 30 and 33mm torsion bars must requre the engine to be lifted enough to slide in the LCA bolts from the engine bay. Once you lower your 116 with stiffer torsion bars, the LCA bolts no longer clear the LCA! Before I barely was able to get it in by grinding part of each head of the bolts off to eek by the LCA.

Anyhow:

"116 & 119 Alfetta/GTV 6/Milano Torsion bar specifications:

GTV6 Early model:
stock bar:
Rate -- 96lbs/in Diameter -- 23.5mm Length--989mm
Sport Bar:
Rate -- 134lb/in Diameter -- 25.4mm Length -- 989mm
SS Bar:
Rate -- 179lb/in Diameter -- 27.3mm " " -- 989mm

GTV6 Late and Milano:
Stock bar:
Rate -- 93lbs/in Diameter -- 22.8mm Length -- 932mm
*No wonder I hit my oil sump so often with the stock setup!
Sport:
Rate -- 143lbs/in Diameter -- 25.4mm Length -- ""
SS:
Rate -- 191lbs/in Diameter -- 27.3mm Length -- ""

So, I have an '84 and I think that means I have the longer, early style bars.

Another interesting thing I learned was that the GTV6 has stiffer rear springs in the rear than the Milanos do. I'm not sure how much, but the SS springs I have in the rear (143lb/inch) are 39% stiffer than stock on the GTV6 but are 57% stiffer than stock on a Milano. Also, SS springs apparently came in two lenghts, one that lowers an early Milano by 1 inch, and another that lowers it 2 inches.

The dissapointing news is that on my Verde, the drop spindles with bump steer correction reduced my bump steer by a large amount, but at the limit, didn't seem to do that much for my understeer problem. It felt better driving fast on a relatively bumpy road (bump steer correction?) but on a freeway onramp, the front tire howl was still there. I haven't given up entirely yet though, b/c my front camber is at like -1 or less, about the same as I had before. This is kinda funny, b/c on Potenziato's 24V Milano, his camber was roughly the same after he went back to stock spindles as before! The drop spindles were 1 and 1/16th inches longer.

I haven't been able to go to my usual testing spot so I wouldn't call the results conclusive yet, but so far they did less than I was hoping.

I'm going to try to get my camber to around -2.5 or more this weekend but I'm going to my GF's prom so I'm not sure.

Hopefully the results will be better for you Echoleader!
_________________
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I'm kidding -- please don't ban me."

And Louis' humongo brakes!
The D-spindles looks like a larger drop than it is. It has a correction for bump steer too.

Also, Larry mounted the ball joint below the UCA! I didn't notice it until I looked at my own car.

[Grant]

So Prom and all, I managed to get my camber to ~1.8 degrees (Dad used a level, a ruler and some trig). I can't go a whole lot more b/c I originally cut my A-arm spacers down when I lowered the car.

The car does understeer worse than before, but, on tight turns it feels better, and generally feels like I'm going faster aroudn turns...

Someone on the alfagtv6 forum mentioned that with the drop spindles my front roll bar would become even more effective than before due to the higher RC, and I do think that's what is going on here. I didn't take that into consideration when I originally wanted to install them (but I'm just happy they're actually making that much of a difference!) The car seems to roll less than before. While it does understeer a lot, at 8-9/10th's driving the car feels much more composed. Even the pitch of the tire squeal sounds more natural, as the full width of the tire tread is scraping on the pavement, and not the sidewalls.

So, as of now, I think I can either use a softer sway bar up front or figure out a way to stiffen the rear end. I only have one more setting on my RSR rear bar to try and go stiffer, but ultimately I think marginally higher spring rates on the rear is what it's going to take.

[Potenziato]

I just have to say I like the car alot better without the drop spindles. The springs are finally working properly and the brake balance is spot on. The car is much more responsive and the understeer is gone totally. The steering is much, much better and the ride improved too. The car never felt right with the d spindles with two totally different suspensions.

I wouldn't take my words as to the effectiveness of the drop spindle, just with the the kit I was using it didn't work well.

I can't understand why the understeer is so bad with the d spindles. Grant and I both use the 28mm front sway bar which is still softer than the 30mm bar recommended by Ron. Also, I don't think my front springs were barely engaging in the front compared to now.

Grant, if you want to try a 26mm front bar I could lone you one.

[Grant]

Louis, I'm really curious if that will make things better. I'll give you a call this weekend.

I was thinking that maybe the higher roll center made your springs effectively too stiff on the front end only with Ron's setup. Kind of like how the drop spindles are making my front end even more roll stiff, and more willing ot break loose first up front.

It's been interesting, and I'm glad you're happy with your setup finally. Maybe it's time to re-install that "Larry strut brace"?

[BigSwede]

Just to double check, you did adjust the toe after the camber change, right?

[Grant]

No, I left it at 9 degrees of toe out

Just kidding, thanks for the reminder. I set it as well as I could at neutral using an adjustable rod thing. Once I install the full shims I'll go back to the alignment shop and have them finish it up.

[75evo]

Hey Grant,

Come by and you can test drive my 75. No dorifto stunts please.

[slyalfa]

Grant just curious what PSI do you have in the tires?
I notice that I start to get understeer any time my tires are low. I run around 45PSI all round. on my AVS tires.

[Grant]

I'm at 34 all around. I think the reason your car oversteers is b/c your tire pressure is so high!

75evo, I think just getting a ride in your car around a few turns would be enough.

[slyalfa]

45 seem to be I get even tire wear. any lower and I scrub off the inside and out side of the tire. and it will slide all over the place. different tires seem to need different PSI. I had some goodyear(I think) many years ago and they needed 65PSI(65 PSI was stamped on the tire) but with lower PSI on the front the front will just plow and the tires will make a lot of sound. when pumped up they do not make much if any sound when sliding. and seem to sitck better. the front seems to be the most sentive any time they get low, I plow. the back if low seems to just get loud. and I notice that I light them up more when low. This is with stock tire size.

[Grant]

So, this weekend I got underneath the car to adjust my rear sway bar to the stiffest position and see if that would help with my massive understeer.

How happy was I to notice that one of the 14mm bolts that attaches the sway bar end link to the dedion had worked its way off of the car, and probably onto the side of the road somewhere. So all of this time, I was assuming the rear sway bar was on it's 2nd to stiffest setting, and still allowing the car to understeer massively.

I quickly found a 14mm bolt from my parts car, and hooked it up and went for a drive (unfortunately, gone are the expensive looking machined heim joint adapters that I got with my rear RSR bar.) With the sway bar in the same position, I was oversteering by the first turn! It was definitely scary, but atleast it wasn't ploughing like it's been doing for the last few months.

I came back, and set the bar to it's softest setting, and went out for another drive.

Man this thing is fun now! Before I adjusted the rear bar, the inside rear wheel would spin on tight turns, even with my functional LSD. Now with the bar on the softest setting, it still oversteers a bit too much (not so safe, and probably not so fast on the track either) but finally I can dictate whether I want the front wheels sliding, or the rears. I can pitch the car into a turn sideways enough to make even Ron proud, or smoothly enter and leave the turn....it's quite fun indeed.

I didn't have much time this weekend to drive it much but I did manage to make it to Highway 9 (a good reference for you local transaxle guys) for an hour or so. The shankle SS spring rates are just about right for the occasional bumps on the backside of 9 and skyline, but I think they are too soft for any serious dips or rises. I also noticed that with the drop spindles, the car rolls less than before. I can also get oversteer with the bar on the softest postion, like I said above, where as before, I had to have the bar on nearly the stiffest setting jus to keep the car from understeering off the road. It's not perfect, but so far I'm happy with this setup, and I DO think drop spindles made a big difference with my softish spring rates.

I think the mods in my sig. could be a slightly cheaper, and more supple alternative to Ron's coilovers. That being said, I would want coilovers for mostlry track use, even without drop spindles (as I don't think they will do a whole lot.) I think the drop spindles could benefit a coilover car even, as the higher roll center should allow the usage of softer spring up front, which should keep the car from skittering up front on the bumpy stuff.

OK, back to finals.

[BigSwede]

Sounds good!

But one thing is a little confusing, you said: "finally I can dictate whether I want the front wheels sliding, or the rears.". How can you get it to undesteer if it's oversteering a little too much? Are you by any chance referring to power oversteer? With for instance my GTV I can go very fast into a corner but if I drive too fast the rear will pretty much always breaks traction first, if I let it settle I can gently squeeze on the juice and get the rear to stick from the weight shift but not too much or it will start to slide.
Your car sounds ideal, if you can learn to drive with that it's the fastest setup I think.

[Grant]

So I'm not exactly sure what is going on with the car right now as I havne't been able to drive it at the limit as much as I wanted to. But, it does sound a bit like your race GTV. The car really responds to how smooth I am. I should say all cars do, but if I turn into the turn to fast and too sharp, with just enough throttle to keep the same speed, the tail will come out. If I come in slow and gentle like, and give it just enough throttle to keep the same speed, it will push a little. But then, if I come in smooth like above, but get on the throttle too hard or abrubtly, the tail will swing out pretty fast...a little too fast, but I think that's a trait of the dedion or something.

I think the fastest setup would be car that's pretty much neutral I think, as that's maximizing the grip from all 4 corners, but I understand this varies from track to track. As it is, I"m too worried about the rear end coming out on high speed sweepers, so I think it could use some more help in the rear.

At this point, I want to add even more camber up front to start at -2.5 degrees, but then, the tail should be even more willing to come out. I'm wondering then, if I can use a staggered setup (225/45/16 up front, 235/45/16 in the rear) to help counter-act this? By putting more tire on a weak end, can that ultimately give me more speed or do I need to blance the chassis first? Will that cause the rear tires to heat up too much, even though there is theoretically more grip in the rear with the wider tires? I don't have enough racing experience to answer these questions...

[slyalfa]

sounds like mine now.
And I have had one of the links bust holding the back sway.
and I know how bad of a pig it is that way. I almost crashed when that happened.
my normal right turn that I can stay in my lane plowed over 2 exta lanes (lucky no cars in the lanes)

On mine if not in 1st on most turns full power will stick the back.

one thing to think about is the front is almost allways loaded going in to a turn.
as you need to break before the turn and this compresses the front. And the compressed front gives exta grip in the front for a while or untill you give some power.

And something to try(in a safe place). when my back slides out. I can just let go of the steering wheel and grab it again. the wheel will spin faster then I could ever do it.