Hooking up with nitrous and a 3200 stall

[Pro Stock John]

I've done a few things to help my car weight transfer, have the front sway bar off for example.

Does it usually spin at launch or on the 1-2 gear change?

[Joe M 2012 2SS]

Originally Posted by WoodBoss

Nice, hope to see you out making some runs soon. Those gears are going to be pretty stout.

I suppose I may pick up a tenth or so with the gear Frank, but won't run until they are broken in. So it will be a while. Maybe this Fall?
Don't forget to call or PM me when I can come up and polish your car on a Saturday.

Originally Posted by Pro Stock John

I've done a few things to help my car weight transfer, have the front sway bar off for example.

Does it usually spin at launch or on the 1-2 gear change?

It spins through 1st and into 2nd. This happens when I get the 1 wheel burnouts. I'm hoping the Truetrac will fix the 1 wheel peels. It usually dead hooks when both spin during the burnout.

If it doesn't after the Truetrac and 3.91's, I'll try removing the front sway bar.
Thanks for the tip John. I like the drag wheel setup Frank (Wood Boss) got from you, next Spring I'll be wanting one too!

[Pro Stock John]

My local track, hooking on 28" DRs has been hit or miss, completely depends on track prep. I had my best passes on slicks. A local buddy went to a 295/15 DR and he hooked a lot more consistently. So I think spinning can be track issue, not just your burnout, health of your posi.

[WoodBoss]

Originally Posted by Pro Stock John

My local track, hooking on 28" DRs has been hit or miss, completely depends on track prep. I had my best passes on slicks. A local buddy went to a 295/15 DR and he hooked a lot more consistently. So I think spinning can be track issue, not just your burnout, health of your posi.

John do you flash your converter and dead hook or do you power brake it?

[Joe M 2012 2SS]

Originally Posted by Pro Stock John

My local track, hooking on 28" DRs has been hit or miss, completely depends on track prep. I had my best passes on slicks. A local buddy went to a 295/15 DR and he hooked a lot more consistently. So I think spinning can be track issue, not just your burnout, health of your posi.

The 305/45/18 MT ET Street R tires I currently run are 29". Prep at Shadyside is always very good.

The tire that doesn't spin (usually 3 of 4 passes) when doing a burnout is the drivers side. When it does actually spin and heat up, the car dead hooks every time (16 psi).

I point the drivers side rear view mirror so I can see it when I'm at the dragstrip, to see if it spins during the burnout, and also to make sure I have the car just outside the water box in the damp area before burning out.

A buddy of mine has an auto scat pack challenger, he also gets 1 wheel burnouts, but most of the time he gets both wheels spinning on burnouts.

He runs 17" ET street R's that are 28" tall (16 psi). His car does the same thing when he gets the 1 wheel burnouts, it wont hook.

[Joe M 2012 2SS]

What a nightmare this has turned out to be.

I called around every shop I could find in my area, and couldn't find anyone who knew how to do the job.

So I started searching for shops outside 30 miles from my home, and did find one who said he had done several G5 Camaro's....$800 to install.

The day I was going to call to set it up, one of my co-workers told me of a shop 10 miles from my home, and praised the guy for doing excellent work, and told me he wouldn't charge me that much. I called and spent a good amount of time talking with the guy, and he told me no problem...$650.

OK so now I won't need to rent a car, and the cost will also be $150 less.....good deal right?......WRONG!!!! When I go to pick it up the price is changed to $750...What could I do? He had my car..I had nothing in writing....so I paid him.

It gets worse.....MUCH WORSE!!!!....I got the car back on Wed 5-2. It had a whine from 35 mph up. So it may just need to go through the break in period (per Motive gear) of 4 heat cycles. Nope.....gears still whining.

I jacked it up and the "play" in the rear wheels versus what it was originally is ridiculously looser.

So the guy came by today. I jacked it up and showed him this. We went for a drive, he heard the whine. Upon getting back to my home he gives me my $750 back....but says since he didn't buy the gear he cannot reimburse me for it......blames the issue on the Motive gear being bad.....I don't believe the gear was bad.....he told me he fully checked it before installing it when I spoke to him on 5-1......so whatever

So now I'll have to take it to the shop I was originally going to take it to.....and buy another gear....They aren't cheap....Dynosteve gave me a good deal on the one I bought......but since it wasn't installed correctly, Motive isn't going to guarantee it.

So now I get to buy another one.

I'm also wondering since it is whining, if metal shavings are getting in the trutrac, and messing it up as well.

Unreal..........

[JMI]

From personal experience(25+ years) working on Diff's we hadn't had much luck with Motive in the last few years.With a perfect install,they were still noisy.We just use the GM when customer wants 3.91 ratio .We had very good luck with Yukon when we use a different gear ratio for the Gen 5 Camaro.Some brand names are a 2 cut or a 5 cut gear setup and has to be setup differently for a quiet and durable operation.

[Joe M 2012 2SS]

Originally Posted by JMI

From personal experience(25+ years) working on Diff's we hadn't had much luck with Motive in the last few years.With a perfect install,they were still noisy.We just use the GM when customer wants 3.91 ratio .We had very good luck with Yukon when we use a different gear ratio for the Gen 5 Camaro.Some brand names are a 2 cut or a 5 cut gear setup and has to be setup differently for a quiet and durable operation.

I did a few hours of research on the web last night (wish I had done this before getting Motive), and found several people with your professional installation experience that said the same thing.

It appears that Motive used to make their gears in Italy, but now they are made in Korea, and they have had the same whining issues after installation, even when the coast and acceleration pattern, preload, and the backlash is spot on, with the Korean made gears.

I don't know what the cut on the 3.91 gears I bought are. The box just says Motive Gear Performance G886391.

I guess I'm going to get the GM 3.91's.

When the Motive's were installed I bought a Ratech 381 kit that had new head, tail, and carrier bearings, crush sleeve, shims, ring gear and cover bolts, pinion nut, seal, and shims.

When the Motive is swapped out for a GM 3.91, what stuff will I need with it?
The bearings should still be good, shouldn't they?

So a crush sleeve and a new gasket?

[JMI]

New crush sleeve &
New inner pinion bearing for sure.The diff cover gasket is usually reusable,Make sure the seals are perfect..
Motive should be a 5 cut and GM is usually 2 cut.
For a while Yukon 3.91 were actually GM gear.But I think now they have their own 3.91

A friend of mine asked me to do his Gen 4,but was thinking a cheaper gear was good enough.Decided to go with Motive.They were noisy,Then went with Richmond,Same noise.The Richmond had the same part number and box as Motive.Come to find out,Motive & Richmond was from the same location.Finally buddy decided to spend the extra $ on Yukon and the Yukon was dead quiet.
They had warrantied both the Richmond & Motive as defective,I had pictures to prove that they were installed correctly.

[Joe M 2012 2SS]

Originally Posted by JMI

New crush sleeve &
New inner pinion bearing for sure.The diff cover gasket is usually reusable,Make sure the seals are perfect..
Motive should be a 5 cut and GM is usually 2 cut.
For a while Yukon 3.91 were actually GM gear.But I think now they have their own 3.91

A friend of mine asked me to do his Gen 4,but was thinking a cheaper gear was good enough.Decided to go with Motive.They were noisy,Then went with Richmond,Same noise.The Richmond had the same part number and box as Motive.Come to find out,Motive & Richmond was from the same location.Finally buddy decided to spend the extra $ on Yukon and the Yukon was dead quiet.
They had warrantied both the Richmond & Motive as defective,I had pictures to prove that they were installed correctly.

Thanks for the information.

The person who installed my Motive's said he has 35 years experience, and this was the first set of Motives that he had ever had an issue with.

A few things have me somewhat confused though. When I picked it up I asked him if the backlash was set at .007......He didn't say yes....he said it was within proper specs. It is my understanding that with the Eaton Truetrac that the backlash is supposed to be .007.....is this correct?

I asked him if the patterns were centered on the accelerate and coast sides of the gear....again he didn't say yes or no....he said they were good.

When he came by to ride and listen to them whine after I called and told him about the issue, he had the money I gave him for the install in his pocket already counted out....why would he do this if he was sure he installed them properly?

I couldn't find a Yukon for a GM 8.6 218mm in 3.91, but found these in 3.90.
https://www.yukongear.com/productdet...x?ProdID=11976

You mentioned that when people swap to a 3.91 in G5 Camaros', you use the GM gears to avoid noise issues, are the Yukons' that much better for the extra cost vs. the GM?

[frankwjr]

you want these gears...https://www.ebay.com/itm/2010-2015-C...NZ3Q39&vxp=mtr

AAM is 2 cut....still whisper quiet..good luck!

peace.

[Joe M 2012 2SS]

I recorded a video this morning so you all could hear the gear whine.
It's much louder in the car than the microphone on my laptop picked up.

[JMI]

Ft

Originally Posted by Joe M 2012 2SS

Thanks for the information.

The person who installed my Motive's said he has 35 years experience, and this was the first set of Motives that he had ever had an issue with.

A few things have me somewhat confused though. When I picked it up I asked him if the backlash was set at .007......He didn't say yes....he said it was within proper specs. It is my understanding that with the Eaton Truetrac that the backlash is supposed to be .007.....is this correct?

I asked him if the patterns were centered on the accelerate and coast sides of the gear....again he didn't say yes or no....he said they were good.

When he came by to ride and listen to them whine after I called and told him about the issue, he had the money I gave him for the install in his pocket already counted out....why would he do this if he was sure he installed them properly?

I couldn't find a Yukon for a GM 8.6 218mm in 3.91, but found these in 3.90.
https://www.yukongear.com/productdet...x?ProdID=11976

You mentioned that when people swap to a 3.91 in G5 Camaros', you use the GM gears to avoid noise issues, are the Yukons' that much better for the extra cost vs. the GM?

A 5 cut,usually 0.006-0.010. Some are different like the Ford 8.8 as an example.
The 2 cut is 0.003-0.006 usually.
We had very good luck with Yukon.They advertise theirs as 3.90
If you can get the GM or AAM which it's AAM that does their 3.91 gear set for GM at a good $. You might as well take those for piece of mind.

If you also replaced the OEM diff bushings with poly or delrin,you will more than likely hear more gear noise even with a perfect setup.

[Joe M 2012 2SS]

Originally Posted by JMI

Ft

A 5 cut,usually 0.006-0.010. Some are different like the Ford 8.8 as an example.
The 2 cut is 0.003-0.006 usually.
We had very good luck with Yukon.They advertise theirs as 3.90
If you can get the GM or AAM which it's AAM that does their 3.91 gear set for GM at a good $. You might as well take those for piece of mind.

If you also replaced the OEM diff bushings with poly or delrin,you will more than likely hear more gear noise even with a perfect setup.

Bushings were not changed out. I originally planned to do this but after speaking with many people was told the same thing, they would increase noise.

The factory 3.27 gears were quiet, never had any issues with them at all. I have the factory gear that was removed, it looks fine, wear pattern is dead center on both sides.

I haven't found any negative reviews of the Yukon 3.90's online. They do cost about $100 more than the GM gears, but I also have found no negative reviews of the GM 8.6 391's.

I guess I should contact Motive and try to get them to refund my money for the gears I bought that whine so bad, though I have a feeling they will say it's from an improper install. And it may be, I don't know, as the guy who installed it was evasive when I asked him about the pattern and the backlash.

I'm beginning to think I should have just put the Truetrac in, and just kept the stock 3.27's.

Car already has a Circle D 3200 stall, and a Zex 125 Nitrous shot and was getting 1.5X 60' times (when it hooked).