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Stock Fuel Rails, why they don’t keep up

Jack_Toepfer

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Sucks it failed, happy for you that it didn’t fail at the event and that you’ll be in great shape for the race!
 


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16GoManGoHC2

16GoManGoHC2

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Thread Starter #562
Look real nice! Glad to see they have upgraded alloy on the CV joints. I'm not understanding the ant-wheel hop technology aspect though.("different size center shafts"). Too bad about the tranny.
An axle shaft acts like a torsional spring when twisted under load, if axles are exactly the same as one another their resonant twisting frequencies are the same and they can get into a resonant oscillation with one another and make those oscillations grow with intensity just because they are happening at a resonant point they both share because they are the same. So manufactures will make the shafts either different diameters then one another or the same diameter but a different length so their resonant frequencies differ from one another but different lengths requires a offset from center differential mounting location. That’s the reason stock axles are different diameters, not because one predominantly sees more torque then the other like some may believe, it’s about resonating and vibrating as resonance oscillation can occur with vibration patterns as well. DSS uses the exact same shaft left and right side which can help hop and vibration not help prevent it, some is sales pitch too I’m sure but in engineering theory it holds water and is true. Guess I’ll find out soon, I hope lol. (Not hop lol)
 


BULL

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An axle shaft acts like a torsional spring when twisted under load, if axles are exactly the same as one another their resonant twisting frequencies are the same and they can get into a resonant oscillation with one another and make those oscillations grow with intensity just because they are happening at a resonant point they both share because they are the same. So manufactures will make the shafts either different diameters then one another or the same diameter but a different length so their resonant frequencies differ from one another but different lengths requires a offset from center differential mounting location. That’s the reason stock axles are different diameters, not because one predominantly sees more torque then the other like some may believe, it’s about resonating and vibrating as resonance oscillation can occur with vibration patterns as well. DSS uses the exact same shaft left and right side which can help hop and vibration not help prevent it, some is sales pitch too I’m sure but in engineering theory it holds water and is true. Guess I’ll find out soon, I hope lol. (Not hop lol)


Hmmm....
 


coolblue

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Ive rebuilt a few rea
An axle shaft acts like a torsional spring when twisted under load, if axles are exactly the same as one another their resonant twisting frequencies are the same and they can get into a resonant oscillation with one another and make those oscillations grow with intensity just because they are happening at a resonant point they both share because they are the same. So manufactures will make the shafts either different diameters then one another or the same diameter but a different length so their resonant frequencies differ from one another but different lengths requires a offset from center differential mounting location. That’s the reason stock axles are different diameters, not because one predominantly sees more torque then the other like some may believe, it’s about resonating and vibrating as resonance oscillation can occur with vibration patterns as well. DSS uses the exact same shaft left and right side which can help hop and vibration not help prevent it, some is sales pitch too I’m sure but in engineering theory it holds water and is true. Guess I’ll find out soon, I hope lol. (Not hop lol)
I've rebuilt a few rears over the years. All pumpkin style. Early Chevy's and Ford 9's. They always have different axle lengths because of the offset pumpkin. My education on the subject was that the center section was always offset so the u-joint would stay under load and act like a u-joint. I never heard about the oscillation aspect. Maybe that trait is more exaggerated with the independent rears. Either way, breaking rears and snapping axles happened same as breaking rears and wiping out CV's on the Hellcats. Science has a hard time dealing with stupidity and abuse. LOL.
 


Jack_Toepfer

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Ya know, I’ve never considered that the axle shafts in a solid rear end played a role in wheel hop, because the cures for that were always attached to the axle housing and had nothing to do with the actual axle. We didn’t upgrade to different axles unless we snapped the old ones.

With an IRS we can’t just reinforce and triangulate the axles to the chassis nor can we really manipulate the position of the diff, so they started messing with the diameters, lengths, and materials of the axle shafts themselves. Nobody has developed a silver bullet, unfortunately, but the “different shafts” approach has worked for some people. First time this started bothering me was in 2002 with a 2003 Cobra… the cure was more power and more tire and the axles remained stock. It’s different for every car because more tire on the HC helped, but as we all know, doesn’t stop it.
 


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Ya know, I’ve never considered that the axle shafts in a solid rear end played a role in wheel hop, because the cures for that were always attached to the axle housing and had nothing to do with the actual axle. We didn’t upgrade to different axles unless we snapped the old ones.

With an IRS we can’t just reinforce and triangulate the axles to the chassis nor can we really manipulate the position of the diff, so they started messing with the diameters, lengths, and materials of the axle shafts themselves. Nobody has developed a silver bullet, unfortunately, but the “different shafts” approach has worked for some people. First time this started bothering me was in 2002 with a 2003 Cobra… the cure was more power and more tire and the axles remained stock. It’s different for every car because more tire on the HC helped, but as we all know, doesn’t stop it.
Shocks were also very important in the '03/'04 Cobra. My next door neighbor was Ron Butler who was Shelbys chassis man at LeMans, bigger tires, better shocks and more power. It worked for my Cobra. He said squat was the worse thing for wheel hop and traction because if the body goes down the tires come up. The tires need to be driven hard into the pavement.
 


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16GoManGoHC2

16GoManGoHC2

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Thread Starter #567
Well here we go again, tranny, Diff, and axles, I really hate mopping this garage floor with my ass lol.
My little buddy is ready to go lol, she’s already looking for what she can make off with lol
5388281E-AF6D-4A37-970B-19A54E669719.jpeg E6E99F2D-4072-4663-866A-31789505F4D3.jpeg
 


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Once you get it out throw away all the bolts and use Velcro or snaps when you reinstall it . This way it will come out quicker in the future !

Sent from my BBF100-2 using Tapatalk
 


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Once you get it out throw away all the bolts and use Velcro or snaps when you reinstall it . This way it will come out quicker in the future !

Sent from my BBF100-2 using Tapatalk
Now may not be the time for humor.😂😂
 


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16GoManGoHC2

16GoManGoHC2

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Thread Starter #570
It’s out, magnet shows some of the debris but I’m sure way from all of it lol
Next stop RSG for all new guts.
A6615E57-7732-40EE-92B2-C849D78629DE.jpeg 8BB19389-4C63-45C3-B63D-41516D72782E.jpeg 35A2B346-6505-4E33-80A4-73BA8B200B28.jpeg
 


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16GoManGoHC2

16GoManGoHC2

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Thread Starter #571
Had a scare when I looked in the cats upon removing the exhaust system, bits of spark plug porcelain :(

Which delayed trans removal to pull all the plugs, they all looked like the day they came out of the box thank God, whew!!!! I was sweating it with each plug removal waiting for the bad one 😅

Did a leak down test on all cylinders as a just in case, weird all the ones on drivers side exactly the same at 3%, 100/97 psi, passenger side 2 at 3% 2 at 4%, this a cold test, 68F in the garage. So now I have a base line going forward. Bore scoped each cylinder as well, amazing how clean corn keeps everything including the exhaust, I wiped my finger around in the collectors and didn’t even get grey dust on my finger.
420B7CBE-187C-4F90-AF23-660C0520E296.jpeg 83F865BE-27F1-41A1-8570-6CA81823E2C2.jpeg 771225CA-C084-4EBF-8409-32585BD52BE4.jpeg AD127A0B-212C-41CD-A13A-1F50BF11B347.jpeg 1A2C690E-52FB-4D41-81E5-DAF8E882E52A.jpeg F30137A6-C3D8-4BC2-BEC0-F7AB06DCC117.jpeg 6ECBC4D7-5E1A-4135-8DCD-8D7F6D8A2C8C.jpeg 02BA7B2D-279D-489D-B1D7-E1C2F4D42F67.jpeg 2A26BE20-10BE-4B28-941A-B5CDE47ED954.jpeg 9735053B-6979-41AA-8861-8A7C671AA2C1.jpeg

Brand new cats going on when it goes back together, or possibly catless down pipes if I can find a set quick.
 


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Had a scare when I looked in the cats upon removing the exhaust system, bits of spark plug porcelain :(

Which delayed trans removal to pull all the plugs, they all looked like the day they came out of the box thank God, whew!!!! I was sweating it with each plug removal waiting for the bad one

Did a leak down test on all cylinders as a just in case, weird all the ones on drivers side exactly the same at 3%, 100/97 psi, passenger side 2 at 3% 2 at 4%, this a cold test, 68F in the garage. So now I have a base line going forward. Bore scoped each cylinder as well, amazing how clean corn keeps everything including the exhaust, I wiped my finger around in the collectors and didn’t even get grey dust on my finger.
View attachment 53875 View attachment 53877 View attachment 53878 View attachment 53879 View attachment 53880 View attachment 53881 View attachment 53882 View attachment 53883 View attachment 53884 View attachment 53885

Brand new cats going on when it goes back together, or possibly catless down pipes if I can find a set quick.
I have a brand new set of ARH catless mid pipes for sale


Sent from my iPhone using Tapatalk
 


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Speedy!

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Did a plug ever fail? Could that be material from the cats?
 


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I just did the plug dance, after seeing how clean yours are. E85 might be just the ticket.
 


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16GoManGoHC2

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Thread Starter #576
Did a plug ever fail? Could that be material from the cats?
2 years ago had a detonation event from bad gas, 2 and 7 had plug damage. I’ve had this exhaust off a few times since and looked at the cat elements closely every time and before putting it back on after the engine rebuild I even blew it out in reverse with a 700 CFM back back leave blower and inspected it pretty damn well, no idea where these bits where hiding at in the cats. That’s why I was so concerned when I saw them and couldn’t continue on removing the trans as I had to know if I had a melt down again snd if entire engine had to come out again or not. You have no idea how glad I was to see 16 like new plugs and good leak down numbers from all cylinders :)
I proceeded to change the oil, take another oil sample to send to Blackstone during the drain, cut the filter open and inspected the can for debris stuck to the inside as I put 3 Filter Mags on the filter, it has 360 degree super magnets around it, it had only very faint collections of magnetic debris which would be ring and cylinder materials, break in and bedding of rings to cylinders is 99.9% done now.
Drop the trans off Tuesday for a hopefully pickup this Friday. This week while waiting on it change out the Diff and put the new axles in and hopefully be back in the saddle by this time next week 🤞🙏
 


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16GoManGoHC2

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Thread Starter #577
Did a plug ever fail? Could that be material from the cats?
Zoom in on the pic’s of the cats and you’ll see the bits laying in them, that’s just how they were when I removed the exhaust. I have 2 brand new cats that I’m putting back on and trading these 2 originals in next month at the cat recall visit along with the 4 original O2 sensors to replenish my stock :)

A00AEF43-971A-4FDE-8424-E300A713372F.png BA23AB4A-34F2-4B6A-B5CE-36A68A927CA0.png

I found a set of cat delete pipes, now the decision to buy them or not and put them on??? Opinions on that??
 


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16GoManGoHC2

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Thread Starter #578
I have a brand new set of ARH catless mid pipes for sale


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Can you PM me pics and price ?
 


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16GoManGoHC2

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Thread Starter #580
Could that be material from the cats?
I thought the same thing at first but look at this piece in the center of the bits, it’s a piece of spark plug porcelain no doubt. And the other round bits look exactly the same at it composition wise. None of them magnetic and they don’t react to a acid that would eat them away if they where aluminum from pistons. They round ones got round from twirling around in there a gazillion times just like pebbles in a stream from eons of rolling around in a brook. I just thank God their eons old not new :)
07817A59-678B-4814-B6B4-5931DE0481B2.png
 




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