Wheel hop

[bigjae46]

What would be the best way to test that? Bonus points if it doesn't involve removing the diff from the car lol

Jack up one rear wheel and turn the wheel on the axle nut with a torque wrench. Should turn smoothly especially if the diff is not new.

[heinzboehmer]

Jack up one rear wheel and turn the wheel on the axle nut with a torque wrench. Should turn smoothly especially if the diff is not new.

Transmission in gear I'm assuming, right? Also any specific torque I should be looking for or just kinda make sure it's not binding?

[bigjae46]

Transmission in gear I'm assuming, right? Also any specific torque I should be looking for or just kinda make sure it's not binding?

Typically about 60-70 ft/lbs when new. Less as the clutches wear.

[Casa de Mesa]

Typically about 60-70 ft/lbs when new. Less as the clutches wear.

Brilliant. I'll do this. Is this with the tranny not in gear? Thinking it wouldn't turn at all if it was in gear.

[bigjae46]

Brilliant. I'll do this. Is this with the tranny not in gear? Thinking it wouldn't turn at all if it was in gear.

That's what I get on the bench. I install the flanges. I lock one flange in the vise and then turn the other one. I'm guessing the reading would be MUCH higher if the transmission was in gear?

[heinzboehmer]

That's what I get on the bench. I install the flanges. I lock one flange in the vise and then turn the other one. I'm guessing the reading would be MUCH higher if the transmission was in gear?

Oh I thought that you would want to lock everything except one output flange so that you can measure the torque needed to slip the clutches. But yeah I guess 60-70 ft lbs with everything locked would be quite bad

[Casa de Mesa]

That's what I get on the bench. I install the flanges. I lock one flange in the vise and then turn the other one. I'm guessing the reading would be MUCH higher if the transmission was in gear?

Yeah that's my possibly faulty thought too, because in theory you'd be testing the amount of clamping force of the clutches alone without any other resistance.

With this method, it seems like this would be only be an indicator. I would think forces are much different when torque is applied to via the drive flange and in the real world with the diff up to operating temps. Reason being, 60-70 ft/lbs before breaking loose into 1-wheel peel seems really small. So actual conditions will be different, and this truly will only measure pre-load. Which... is the whole point.

[bigjae46]

Yeah that's my possibly faulty thought too, because in theory you'd be testing the amount of clamping force of the clutches alone without any other resistance.

With this method, it seems like this would be only be an indicator. I would think forces are much different when torque is applied to via the drive flange and in the real world with the diff up to operating temps. Reason being, 60-70 ft/lbs before breaking loose into 1-wheel peel seems really small. So actual conditions will be different, and this truly will only measure pre-load. Which... is the whole point.

I'd be looking to make sure the diff isn't totally locked up.

[Epoustouflant]

Hey Br!

What are the driving behaviours you’ve changed to avoid the hop?

This will help drill it down.

Hope you’re enjoying the holidays.

[Casa de Mesa]

I'd be looking to make sure the diff isn't totally locked up.

This much I know already - the diff is definitely not totally locked up.

Hey Br!

What are the driving behaviours you’ve changed to avoid the hop?

This will help drill it down.

Hope you’re enjoying the holidays.

Hey Matt! Holidays are going great, hope yours are too!

Getting wheel hop on the right rear (*nearly* sure it's only the right rear) whenever the tire breaks traction. That's whether its from a dig/launch racing a Civic, or if I poke the bear and purposely try to light the tires up in dramatic fashion while leaving a stop light in front of the local constabulary, or if I try to hoon it and hang the ass end out around a traffic circle at the elementary school drop off lane. Thus, changing my behavior/driving around it means not doing anything that involves throttle oversteer which means greatly limiting my fun. Maybe it's an anti-jail device.

[Thrifty S50]

I mentioned sways earlier as I know in the truck world, they make a massive difference in wheel hop when doing stand still burnouts. I figured maybe it got bent or something. The car should be able to do stand still burnies with ease w/out wheel hop Dry or wet. I do it often. It shouldn't hop mid drift either, ive never experienced hop during drift, but am on a considerably less grippy tire (255 Federal RS-R). Id be curios if airing up you're tires reduces the hop. I know you redid the rear end as well, did anything pop up during alignment? If I were you, just to rule out suspension components I would throw a go pro under the car, or tape it in the wheel welll and rip a fat burnout and see if theres a visible weak link. Gonna be a process of elimination, but once solved please record and post a victory burnout for us lol

[heinzboehmer]

Casa de Mesa, I've had a similar issue (along with a noise) for a bit now and I just figured out what it was. Turns out the bolts holding the lower control arms to the subframe were very loose (< 25 ft lbs). Tightened them to spec and no more vagueness or noise or wheel hop or anything.

Kind of a long shot, since it's doesn't seem to be a common failure (and it could well have been my fault), but thought I'd let you know as it's an easy thing to check.

[Casa de Mesa]

Casa de Mesa, I've had a similar issue (along with a noise) for a bit now and I just figured out what it was. Turns out the bolts holding the lower control arms to the subframe were very loose (< 25 ft lbs). Tightened them to spec and no more vagueness or noise or wheel hop or anything.

Kind of a long shot, since it's doesn't seem to be a common failure (and it could well have been my fault), but thought I'd let you know as it's an easy thing to check.

Oh wow, that's an interesting one I'd not heard of before.

You're talking about the inward bolt that mounts to the subframe on the equivalent of these arms:

https://www.ecstuning.com/b-turner-motorsport-parts/rear-adjustable-camber-arm-street/tsu9940b77/

Those are the exact RLCAs I have and I've wondered if it's the bushing going bad. Every other bushing is brand new... except for those which have about 10 years and 50k miles on them.

I'll look to see if they backed out - I used an oil/paint pen to mark the fasteners when I torqued them during the rear suspension overhaul. I'll re-torque them regardless. Appreciate this Heinz!!

[heinzboehmer]

Yep! That's the bolt.

I also paint marked everything when I did my vincebar, so I thought the bolts were fine. Wasn't until I put a wrench on them that I found they were super loose.

[Casa de Mesa]

Weird they were loose. OK, I'll definitely give it a go!