gmoran1469

Yup, that's the plan. I have a feeling one too many hard launches on 275 NT-01's took it's toll. Started putting away some cash yesterday.

Any suggestion on which one? 1-piece Alu of course.

Reno Stack

Perhaps your pinion angle is off when you installed the 3rd link?

http://www.steeda.com/store/uploads/...-upper-c-1.pdf

gmoran1469

I set it back to spec, which being a 2-piece DS was a pretty wide range.

Maybe it needs to be set different due to the lowering?

Before I installed the 3rd-link I measured it and put it back to that once installed.

Sam Strano

Sounds like a tune issue to me. Bucking at part throttle, and remember that the throttle is fly by wire. Think about what you were saying the car does and WHEN. It's always on situation where you are opening or closing the throttle. And I bet if you step on the clutch, it'll stop. Further I bet the stock tune won't do it, at least as much... which rules out suspension issues.

gmoran1469

It's not bucking from the engine, it feels like it's in the suspension. The engine RPM doesn't do anything I wouldn't expect it to.

I also tuned it back to stock and did a throttle recalibration and it feels the exact same.

Best way to describe it, the 3-link holds the rear end in place and it feels like it has forward and backward slack (going towards the front and back of the car, so lengthwise), but I know that is not the case.

What I think I am feeling is slack in the DS and it gaining some momentum, then binding.

The bucking also isn't at part throttle, it's when im slightly on it, then slightly off.

Scenario: very slight throttle in 1st (10-12mph), let off throttle, slight clunk forward, get back on slight throttle, slight clunk backward.

I also feel it if I don't let the clutch out perfectly at the exact rpm needed. Or if I don't feather it a little as I release the clutch.

gmoran1469

So why I think it's not the engine and is in the drivetrain/suspension:

1st gear, at a stop. Give it some gas as I ease the clutch out, before the clutch it all the way out, but the car is moving, push the clutch back in and there is a clunk.

That's why I think the DS is binding then releasing slack and I am hearing the release of the bind.

Either that or it's something with the tranny/clutch.

gmoran1469

So while my play money funding slowly builds back up I am thinking more and more about the feeling the rear is giving me.

I took some video of the DS and it looks fine. I don't see any jerky movement in it I could relate to the slack feeling so I am left to thinking it's just me not liking the feeling of the UMI 1055 PHB w/ roto's.

I have a sneaking suspicion it's just the roto's wearing down a bit as time goes on and becoming slightly looser feeling. It happens when the rear end goes up and down (on and off throttle) and I can hear the sound it makes but not the feeling when I am not giving it throttle and I go over a pothole.

The more I learned about the way the PHB and 3-link system worked the more I started to lean towards it just being the PHB.

Watt's link in the near future perhaps.