Page 4 of 5 FirstFirst ... 2345 LastLast
Results 46 to 60 of 68
  1. #46
    Join Date
    Feb 2019
    Location
    Southeast Michigan
    Posts
    268
    Post Thanks / Like
    Quote Originally Posted by 91DakBuilder View Post
    I use the factory pink bolts with blue loctite. So far so good. Just put my factory driveshaft back in for a road trip. I’ll do the same method of blue loctite on the DSS shaft when I put it back in as well
    I think the "pink bolts" are for the older style cars though....the newer ones use a T50 torx bolt
    2019 Charger Scat Pack
    Thanks 91DakBuilder thanked for this post

  2. #47
    Join Date
    Dec 2014
    Posts
    575
    Post Thanks / Like
    Quote Originally Posted by snobrdrdan View Post
    I think the "pink bolts" are for the older style cars though....the newer ones use a T50 torx bolt
    You’re right I didn’t catch that I’ve got a 13 R/T. Not a 15+. That is terrible you have to deal with the Torx trash.


    Sent from my iPhone using Tapatalk
    13 Durango R/T
    13 M6 Challenger R/T
    02 M5 Dakota QC Sport
    91 TKO 600 Dakota CC
    63 Dart 3 on da Tree

  3. #48
    Join Date
    Feb 2019
    Location
    Southeast Michigan
    Posts
    268
    Post Thanks / Like
    Big thank you to ronan978 for the DIY write up. You made it sound/look simple and convinced me to DIY it.
    I did it by myself, and I gotta say it was a little tricky trying to manhandle the diff and getting everything to line up while on my back (with the car on ramps).

    It's done but, again, it wasn't fun


    Here's another good write-up, btw, if you want to add it to the first post:
    https://static1.squarespace.com/static/58eed750d1758e9c1359a528/t/58f69446579fb3776b327ec7/1492554943722/TECH+ARTICLE+DIFFERENTIAL+REPLACEMENT+15+AND+UP.pd f

    And my driveshaft bolts were T50 torx heads
    Last edited by snobrdrdan; 03-22-2019 at 04:17 AM.
    2019 Charger Scat Pack
    Thanks ronan978 thanked for this post
    Likes ronan978 liked this post

  4. #49
    Join Date
    Aug 2016
    Posts
    3,082
    Post Thanks / Like
    Quote Originally Posted by MXS67454 View Post
    Great write up Ronan978 .. I've read your posts on results of your 3.70 swap and am not surprised at the lack of improvement.. you stated you believe the 3.70 is too much gear for the A8 and I submit it's not too much but the wrong gear for a stock or in your case a mildly modified 6.4 and here's why .. I used an online gear calculator over a year ago when deciding on a gear change for my A8 Scat. assuming an average trap speed of a stock 6.4 is around 113 mph . below are the rpm's crossing the stripe at the end of the 1/4 using different gear ratios.

    3.09 @ 113 mph in 5th gear = 5273 rpm
    3.70 @ 113 mph in 5th gear = 6315 rpm ( too high )
    3.70 @ 113 mph in 6th gear = 4895 rpm ( too low )
    3.90 @ 113 mph in 5th gear = 6656 rpm ( way too high )
    3.90 @ 113 mph in 6th gear = 5159 rpm

    too high or too low rpm and you lose acceleration.
    the 3.70 with close to stock hp is the wrong choice for the drag strip in 5th or 6th gear .(it could be a good choice for a high hp N/A or low hp F/I )
    also, look how close the finish line rpm is between the stock 3.09 in 5th gear is to the 3.90 is in 6th ...almost the same except the 3.90 accelerates faster . I gained .2 with my 3.90 swap.
    an N/A 6.4 with 3.90 and a cam that would go to 7k would be an interesting experiment.
    I'm trying to shine some light on why things turned out the way they did . not Sh*T on what you've done. hopefully I accomplished that...

    also have you looked into the Per4mance Development rear differential brace to fix your wheelhop ? I have one on my 700 whp Scat and it really tightens up the rear.. no hop period..
    Just wanted to touch on this a bit more :
    This weekend I decided to put the 3.70 back in the car. Now with ported heads , custom cam , and a 426 along with fbo. Any how , another thing relative to this gear is going to be tire size. I’m now running the 3.70 with a 305/40/18MT SS(27.6”) about an inch smaller than oem. With the stroker , cam , gear and tire , the car feels incredible and is almost always in its powerband. I haven’t run any numbers or tests yet , but damn it feels good.

    Back to the original post quoted: I feel the 3.70 could be an optimal choice depending on the tire size chosen. We can deviate all the way down to a 27” tire to bring it closer to the 3.90’s rpm at the line in 6th gear, or we can run a larger 29-30” and find what would probably be the happiest middle ground crossing at 6k in 5th. [for a stock/mild 392] My numbers will be different, but I’ll get back when I get a chance to do some runs.




    Sent from my iPhone using Tapatalk
    Likes MXS67454, punisher69 liked this post



  5. #50
    Join Date
    Sep 2018
    Posts
    7
    Post Thanks / Like
    Will the challenger differential work as well? I'm looking at getting the 3.09 LSD for my 2018 300.

  6. #51
    Join Date
    Aug 2016
    Posts
    3,082
    Post Thanks / Like
    Quote Originally Posted by 18Hemi300 View Post
    Will the challenger differential work as well? I'm looking at getting the 3.09 LSD for my 2018 300.
    Yessir


    Sent from my iPhone using Tapatalk

  7. #52
    Join Date
    Sep 2018
    Posts
    7
    Post Thanks / Like
    Cool. Thanks for the info Ronan!! Got in a huge debate on the 300 Facebook page because guys said the 300s are different. Luckily it's already been done by one guy. The axle shafts are smaller, but the spline that goes in the housing are the same size.
    Thanks thewayfastwhitey thanked for this post
    Likes thewayfastwhitey, ronan978 liked this post

  8. #53
    Join Date
    Aug 2016
    Posts
    3,082
    Post Thanks / Like
    Quote Originally Posted by 18Hemi300 View Post
    Cool. Thanks for the info Ronan!! Got in a huge debate on the 300 Facebook page because guys said the 300s are different. Luckily it's already been done by one guy. The axle shafts are smaller, but the spline that goes in the housing are the same size.
    No worries! My 3.70 came out of a hellcat challenger. But we’ve swapped a 3.09 ,3.70 , and a 3.90 into my buddy’s 5.7 multiple times with said axles.


    Sent from my iPhone using Tapatalk

  9. #54
    Join Date
    Jun 2012
    Posts
    129
    Post Thanks / Like
    Ok this is a lot of good information. So I currently have the 3:09 and want to change to the 3:70 would you recommend this change with the 6.4 running a ProCharger??? Currently running a 315 drag radial.

  10. #55
    Join Date
    Aug 2016
    Posts
    3,082
    Post Thanks / Like
    Quote Originally Posted by BDL View Post
    Ok this is a lot of good information. So I currently have the 3:09 and want to change to the 3:70 would you recommend this change with the 6.4 running a ProCharger??? Currently running a 315 drag radial.
    At the moment , I have every intention on doing just that. Right now with the na stroker it is fantastic!! Always in the powerband. I would imagine it being a good combination with a centri blower too as it’ll keep you in the higher power band at wot , but still have nice torque at part throttle when the blower is in less use(if that makes any sense Changing your 15+ zf rear....). Especially since you can play with the tire size a bit. I’m not going to lie , traction can be tough in first , but the following gears fall in line sooo much better. Also , with the 3.09 , I was NEVER using eighth gear.


    Sent from my iPhone using Tapatalk

  11. #56
    Join Date
    Jun 2012
    Posts
    129
    Post Thanks / Like
    Quote Originally Posted by ronan978 View Post
    At the moment , I have every intention on doing just that. Right now with the na stroker it is fantastic!! Always in the powerband. I would imagine it being a good combination with a centri blower too as it’ll keep you in the higher power band at wot , but still have nice torque at part throttle when the blower is in less use(if that makes any sense Changing your 15+ zf rear....). Especially since you can play with the tire size a bit. I’m not going to lie , traction can be tough in first , but the following gears fall in line sooo much better. Also , with the 3.09 , I was NEVER using eighth gear.


    Sent from my iPhone using Tapatalk
    Thanks!!! I will put in the 3:70 gears once the 6.1 intake is finished just waiting for everything to return from powder coating.
    Thanks GreyMax thanked for this post

  12. #57
    Join Date
    Aug 2016
    Posts
    3,082
    Post Thanks / Like
    Quote Originally Posted by BDL View Post
    Thanks!!! I will put in the 3:70 gears once the 6.1 intake is finished just waiting for everything to return from powder coating.
    Which intake are you swapping ?


    Sent from my iPhone using Tapatalk

  13. #58
    Join Date
    Jun 2012
    Posts
    129
    Post Thanks / Like
    I’m putting on the 6.1 intake and hope to be done in a month then to the dyno we go and see what it does.

  14. #59
    Join Date
    Jun 2012
    Posts
    129
    Post Thanks / Like
    Swapping the 6.4 for the 6.1 sorry.

  15. #60
    Join Date
    Aug 2016
    Posts
    3,082
    Post Thanks / Like
    Quote Originally Posted by BDL View Post
    Swapping the 6.4 for the 6.1 sorry.
    Just did the exact same , I cleaned up all the cast flash , opened to throat up to ~86mm and gasket matched the ports. Picked up 28whp but sacrificed 4rtq(on a 426). A fair trade imo. Also now the acceleration is much more linear, pulls hard all the way thought the rpm’s, no more falling flat after 5k And it’s ready for a centri when the time comes


    Sent from my iPhone using Tapatalk

Page 4 of 5 FirstFirst ... 2345 LastLast

Tags for this Thread

Share This Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •