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904 low gear set #1710767 12/14/14 11:09 PM 12/14/14 11:09 PM
Joined: Feb 2008 Posts: 128 West Michigan 7 76318dart OP member
76318dart OP member 7 Joined: Feb 2008 Posts: 128 West Michigan	First I'll start with my combo: 340 4in crank Rhs indy heads 2.02/1.625 mild port work crower solid roller 624/627 104cl 258/262 11:1 pistons eldelbrock Victor intake pro systems holley 830cfm 904 tranny w/8in turbo action 5000stall 8 3/4 4.10 gears. 3250lb dart Well the best time I have so far at the track is 11.00 at 119. I was starting to think if I would benifit with getting rid of the low gear set or changing gears? BTW I run 27x10.5 hoosiers and I have a little bit of suspension work to do. I spin a litter and it bounces on the launch. SS springs. My 60ft is 1.52 and 1/8 mile is 6.99 @96.5 mph. Thanks 76 dart 318 runs 12.9o @ 103 mph with 1.78 60ft.

Re: 904 low gear set [Re: 76318dart] #1710768 12/14/14 11:27 PM 12/14/14 11:27 PM
Joined: Apr 2011 Posts: 319 jonestown,pa D dmking enthusiast
dmking enthusiast D Joined: Apr 2011 Posts: 319 jonestown,pa	does it launch and then settle down and then spin or spin out off the hit?

Re: 904 low gear set [Re: dmking] #1710769 12/14/14 11:42 PM 12/14/14 11:42 PM
Joined: Feb 2008 Posts: 128 West Michigan 7 76318dart OP member
76318dart OP member 7 Joined: Feb 2008 Posts: 128 West Michigan	Likes to pull the front tires off the ground and either while it's doing that it spins or when the front comes down and it bounces and then spins. I have a pinion snubbed and longer shocks in the back with 80/20 adjustable shocks in the front 76 dart 318 runs 12.9o @ 103 mph with 1.78 60ft.

Re: 904 low gear set [Re: 76318dart] #1710770 12/15/14 12:00 AM 12/15/14 12:00 AM
Joined: Apr 2011 Posts: 319 jonestown,pa D dmking enthusiast
dmking enthusiast D Joined: Apr 2011 Posts: 319 jonestown,pa	my car had that happening and i was told to lower the spring rate (turn the bars down some) it helped a lot if you have the clearance under the oil pan anyway.

Re: 904 low gear set [Re: dmking] #1710771 12/15/14 12:05 AM 12/15/14 12:05 AM
Joined: Jan 2003 Posts: 5,894 Florida Locomotion master
Locomotion master Joined: Jan 2003 Posts: 5,894 Florida	What kind of shocks do you have all around? By "bounce", do you mean the front end is bouncing, rear is bouncing (wheel-hop) or both? Off hand I'm wondering if the shocks are too loose/soft all around.

Re: 904 low gear set [Re: 76318dart] #1710772 12/15/14 12:33 AM 12/15/14 12:33 AM
Joined: Sep 2004 Posts: 1,499 San Antonio,TX 4 440W8 Duster pro stock
440W8 Duster pro stock 4 Joined: Sep 2004 Posts: 1,499 San Antonio,TX	Quote: First I'll start with my combo: 340 4in crank Rhs indy heads 2.02/1.625 mild port work crower solid roller 624/627 104cl 258/262 11:1 pistons eldelbrock Victor intake pro systems holley 830cfm 904 tranny w/8in turbo action 5000stall 8 3/4 4.10 gears. 3250lb dart Well the best time I have so far at the track is 11.00 at 119. I was starting to think if I would benifit with getting rid of the low gear set or changing gears? BTW I run 27x10.5 hoosiers and I have a little bit of suspension work to do. I spin a litter and it bounces on the launch. SS springs. My 60ft is 1.52 and 1/8 mile is 6.99 @96.5 mph. Thanks You don't need that low gear set in the car with a 4in stroke. 70 Duster W8 motor. 1.29 60ft 5.79 1/8 at 120 mph glide with 1.80 gear @3170 lbs.

Re: 904 low gear set [Re: 440W8 Duster] #1710773 12/15/14 12:48 AM 12/15/14 12:48 AM
Joined: Feb 2008 Posts: 128 West Michigan 7 76318dart OP member
76318dart OP member 7 Joined: Feb 2008 Posts: 128 West Michigan	The front and back are both bouncing.The fronts are comp engineering 3 ways and the backs are mopar longer gas shocks. So about the low gear set you think it's hurting me overall? 76 dart 318 runs 12.9o @ 103 mph with 1.78 60ft.

Re: 904 low gear set [Re: 76318dart] #1710774 12/15/14 01:12 AM 12/15/14 01:12 AM
Joined: Sep 2004 Posts: 1,499 San Antonio,TX 4 440W8 Duster pro stock
440W8 Duster pro stock 4 Joined: Sep 2004 Posts: 1,499 San Antonio,TX	When I ran SS/springs I ran the MP shocks for a Manual Trans and the same front shocks you have and no pinion snubber and best 60ft 1.32 1/8th 6.16 and 9.77@ 137. 727 standard gears 4.30 rear gear with a 29.5 tire. 70 Duster W8 motor. 1.29 60ft 5.79 1/8 at 120 mph glide with 1.80 gear @3170 lbs.

Re: 904 low gear set [Re: 76318dart] #1710775 12/15/14 01:15 AM 12/15/14 01:15 AM
Joined: Jan 2003 Posts: 5,894 Florida Locomotion master
Locomotion master Joined: Jan 2003 Posts: 5,894 Florida	I agree with 440W8 Duster about not needing the low gearset with all the cubic inches you have. But your rear shocks are definitely too soft and not controlling the leaf springs. Rancho 9-way should help the rear. Front may be too loose, especially if they are old. Try different adjustments, but consider changing the rears first and work in going back to the standard 2.45 low gear. One thing at a time.

Re: 904 low gear set [Re: Locomotion] #1710776 12/15/14 01:20 AM 12/15/14 01:20 AM
Joined: Feb 2008 Posts: 128 West Michigan 7 76318dart OP member
76318dart OP member 7 Joined: Feb 2008 Posts: 128 West Michigan	Okay thanks guys. Im gonna get some new shocks for the back for sure. I have some 373s all set up in another case with a spool. Might try those first. The car is 80% street btw. 76 dart 318 runs 12.9o @ 103 mph with 1.78 60ft.

Re: 904 low gear set [Re: 76318dart] #1710777 12/15/14 01:33 AM 12/15/14 01:33 AM
Joined: Jan 2003 Posts: 5,894 Florida Locomotion master
Locomotion master Joined: Jan 2003 Posts: 5,894 Florida	By "low gear set", we mean in the trans. Not sure how the 4.10's work in the 1/4, but the idea is to go through the 1/4 mile finish near or a bit higher than your optimim shift points. But obviously you need streetability too. The 3.73 will help calm it down a bit off the line, so it should help for now.

Re: 904 low gear set [Re: Locomotion] #1710778 12/15/14 01:42 AM 12/15/14 01:42 AM
Joined: Feb 2008 Posts: 128 West Michigan 7 76318dart OP member
76318dart OP member 7 Joined: Feb 2008 Posts: 128 West Michigan	Yeah I know in the tranny. I used to have a 318 in the car so I put the low gear set in the trans. I shift the car at 6500 and I go thru the traps at 6450. 76 dart 318 runs 12.9o @ 103 mph with 1.78 60ft.

Re: 904 low gear set [Re: 76318dart] #1710779 12/15/14 01:46 AM 12/15/14 01:46 AM
Joined: Sep 2004 Posts: 1,499 San Antonio,TX 4 440W8 Duster pro stock
440W8 Duster pro stock 4 Joined: Sep 2004 Posts: 1,499 San Antonio,TX	Yes if you are shifting at 6500 you want about 6600-6700 at the finish line. 8362628-IMG_20140607_191237_116.jpg (93 downloads) 70 Duster W8 motor. 1.29 60ft 5.79 1/8 at 120 mph glide with 1.80 gear @3170 lbs.

Re: 904 low gear set [Re: 440W8 Duster] #1710780 12/15/14 01:51 AM 12/15/14 01:51 AM
Joined: Feb 2008 Posts: 128 West Michigan 7 76318dart OP member
76318dart OP member 7 Joined: Feb 2008 Posts: 128 West Michigan	So I'm gonna start with the shocks for sure. Then once I get the suspension figured out I'll probably go back to the standard 2.45 in the tranny. 76 dart 318 runs 12.9o @ 103 mph with 1.78 60ft.

Re: 904 low gear set [Re: 440W8 Duster] #1710781 12/15/14 02:33 AM 12/15/14 02:33 AM
Joined: Jan 2003 Posts: 4,448 Phoenix, AZ M MoparBilly master
MoparBilly master M Joined: Jan 2003 Posts: 4,448 Phoenix, AZ	Low gear set is fine, all your numbers are right in line for the power you are making. You need less weight, or more power if you want consistent 10s. I have 4.125 stroke, and about the same weight, and I have no intention of giving up my low gear set, I'd rather adjust the final gear ratio to adjust the car. I have 3.89's in the 9 inch, with 28 tall tires. Street driven. 8362683-ADRA1.jpg (121 downloads) "Livin' in a powder keg and givin' off sparks" 4 Street cars, 5 Race engines

Re: 904 low gear set [Re: MoparBilly] #1710782 12/15/14 02:09 PM 12/15/14 02:09 PM
Joined: Dec 2009 Posts: 20,640 in a cattle trailer down by th... G Guitar Jones Paddle faster! I hear banjo music!
Guitar Jones Paddle faster! I hear banjo music! G Joined: Dec 2009 Posts: 20,640 in a cattle trailer down by th...	I took the low gear set out of my car and it didn't make a bit of difference but my car is lighter. "Follow me the wise man said, but he walked behind" '92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion. '74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost coming soon! 2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.

Re: 904 low gear set [Re: Guitar Jones] #1710783 12/15/14 03:30 PM 12/15/14 03:30 PM
Joined: Jan 2005 Posts: 3,635 Oakland, MI D dizuster master
dizuster master D Joined: Jan 2005 Posts: 3,635 Oakland, MI	standard 2.45 gear set will likely make it more consistent because it will knock some starting line ratio out of 1st gear. That will help you get the tire spin under control. But if you can fix the suspension, the car will be quicker with the low gear set.

Re: 904 low gear set [Re: dizuster] #1710784 12/17/14 03:59 PM 12/17/14 03:59 PM
Joined: Dec 2007 Posts: 310 Michigan 4 412 SB Duster enthusiast
412 SB Duster enthusiast 4 Joined: Dec 2007 Posts: 310 Michigan	like others have said, fix the shocks and get rid of the pinion snubber. your car will be quicker with the low gear set, the gear set is not your issue.

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