4.56 gears in a Ram too low?
08-26-2005, 01:53 PM
#21
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Originally Posted by BigPurp
Depends on what rpm your motor turns and tire height as well. If your going to spin 7k and the truck pulls strong up to that point you would be at an advantage giving the truck the strongest mechanical advantage possible.
You really think a truck with 3.55's is going to run the same 1/4 time as one with 4.56?? Your completely out of your mind. Only situation where that would be true is if the truck was running out of gear in the 1/4 which is HIGHLY unlikely.
28" tire (pretty average)
4.56 gears
1:1 3rd gear tranny ratio.
110mph is only turning 6000rpm
Last I checked most trucks that will run 110 have nooooo problem spinning 6k.
Yes it's all dependant on your setup and some motors like to lug lower gears, but with the tire height most rams are running 4.56 are great.
You really think a truck with 3.55's is going to run the same 1/4 time as one with 4.56?? Your completely out of your mind. Only situation where that would be true is if the truck was running out of gear in the 1/4 which is HIGHLY unlikely.
28" tire (pretty average)
4.56 gears
1:1 3rd gear tranny ratio.
110mph is only turning 6000rpm
Last I checked most trucks that will run 110 have nooooo problem spinning 6k.
Yes it's all dependant on your setup and some motors like to lug lower gears, but with the tire height most rams are running 4.56 are great.
It might work that way with the dakotas, but you are so far off with the new gen hemi powered rams its funny, not trying to flame here but I haven't seen a 2003 and up ram turn 7,000 rpms yet, not even really 6,000, you can get close with a programmer, but not many of these guys are running one. Average tire size is about 30.5 inches on the rams running here with factory 20s.
08-26-2005, 02:04 PM
#22
Originally Posted by BigPurp
Hate to tell ya gonz but your wrong in this instance. 4.56 gears are great for 1/4 times as have been proven by numerous hemi rams, 5.9 dakotas, SRT-10's etc. Heck the QC SRT-10 comes with them stock... go figure. If your a lead foot and don't know how to launch then yes you'll smoke them easier, but as for staying in the torque curve, pffft. Last I checked most trucks run much better if you let them pull through the lights at more than 4200rpm.
Not all will drop .4 in the 1/4 but thats a very common number for mildly modified setups. Yes some that make monster power won't see a gain b/c they have the power to pull huge gears to redline anyway.
Whos this 777 guy you seem to be
what are his mods? what does his truck run?
It's a hemi, not a cummins, they don't like to be lugged with tall gears at all.
Not all will drop .4 in the 1/4 but thats a very common number for mildly modified setups. Yes some that make monster power won't see a gain b/c they have the power to pull huge gears to redline anyway.
Whos this 777 guy you seem to be
what are his mods? what does his truck run?It's a hemi, not a cummins, they don't like to be lugged with tall gears at all.
08-27-2005, 03:24 AM
#25
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Well lets look at the power band of a mildly modified hemi. Anyone have a dyno sheet handy?
As stated most hemi rams run 30.5" tires.
We'll cover a good spectrum here.
4.56 gears, 30.5" tire:
100mph=5028
105mph=5279
110mph=5530
That sure does seem like a pretty optimum rpm range to be pulling through the lights.
3.92 gears, same tire:
100=4322
105=4538
110=4754
Unless your rev limiter won't let it spin over 5200 the deeper gears will be a big advantage. Now on nitrous motors with all the torque they build instantly you can get away with a taller gear, same goes for turbo motors, lug them a bit and it spools a lot harder.
Personally I have to say untill you drive a truck with 4.56 gears, and preferably a stall converter to go with it ya really can't talk. I run a 29" slick with 3.92 gears and it's HUGELY over geared. I've never been a big fan of 4.56 with a short tire cause I drive a lot but i'll likely be gearing it very soon. Right now it goes 88mph in the 1/8th and doesn't even hit 3rd gear, but has only pulled 106 in the 1/4 at 4800rpm N/A, LOL.
Oh and those rpm figures are assuming the TC is lockedup.
But just to say oh the fastest trucks around run X gear is a very very bad way to choose parts. It's all about the overall combination, There are guys in the deep 11's with 4.56, soon to be 4.88's, then there are guys with stock 3.92 gears. It's all combo based. But as you start adding cams, pcm, etc your always moving the power UP the rpm range, in which case you can spin lower gears, giving the motor more leverage and thus accelerating faster.
At any rate he ordered them and we'll see how it goes once they are installed. I'm NOT an advocate of super low gears, but with a tall tire they aren't bad at all. (duh) I'd never run them on 27" tires like some of the dak guys tho.
As stated most hemi rams run 30.5" tires.
We'll cover a good spectrum here.
4.56 gears, 30.5" tire:
100mph=5028
105mph=5279
110mph=5530
That sure does seem like a pretty optimum rpm range to be pulling through the lights.
3.92 gears, same tire:
100=4322
105=4538
110=4754
Unless your rev limiter won't let it spin over 5200 the deeper gears will be a big advantage. Now on nitrous motors with all the torque they build instantly you can get away with a taller gear, same goes for turbo motors, lug them a bit and it spools a lot harder.
Personally I have to say untill you drive a truck with 4.56 gears, and preferably a stall converter to go with it ya really can't talk. I run a 29" slick with 3.92 gears and it's HUGELY over geared. I've never been a big fan of 4.56 with a short tire cause I drive a lot but i'll likely be gearing it very soon. Right now it goes 88mph in the 1/8th and doesn't even hit 3rd gear, but has only pulled 106 in the 1/4 at 4800rpm N/A, LOL.
Oh and those rpm figures are assuming the TC is lockedup.
But just to say oh the fastest trucks around run X gear is a very very bad way to choose parts. It's all about the overall combination, There are guys in the deep 11's with 4.56, soon to be 4.88's, then there are guys with stock 3.92 gears. It's all combo based. But as you start adding cams, pcm, etc your always moving the power UP the rpm range, in which case you can spin lower gears, giving the motor more leverage and thus accelerating faster.
At any rate he ordered them and we'll see how it goes once they are installed. I'm NOT an advocate of super low gears, but with a tall tire they aren't bad at all. (duh) I'd never run them on 27" tires like some of the dak guys tho.
08-27-2005, 04:08 AM
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Originally Posted by Rumble Bee Ram
It might work that way with the dakotas, but you are so far off with the new gen hemi powered rams its funny, not trying to flame here but I haven't seen a 2003 and up ram turn 7,000 rpms yet, not even really 6,000, you can get close with a programmer, but not many of these guys are running one. Average tire size is about 30.5 inches on the rams running here with factory 20s.
with stock gears it's turning 4500 @ 105, WAY too low in the power band. Anyway you guys do as you feel right.
And if he's running 13.9 N/A, i've got over a sec on him N/A and I haven't even done a gear change yet either. And I know for a fact mine will drop a good bit when I do. sooooo
08-29-2005, 07:28 AM
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Whats a "mini" truck? We're not talking about S-10's, tacomas and such. If your talking about my dak well last time I checked it still has a V8, and is longer/heavier than a RCSB silverado so not exactly a "mini" truck. If you have some useful info to add please do so, but crying about truck size seems like your compensating for something.