[snrusnak]

^ I thought you originally had 3.55? Maybe I am not remembering correctly...

 

[RamTex]

Well did the track Sat night and no bueno on the gears for me. We did have much higher DA and that affected me as well. I believe i blew through my boost range too fast with the 4.56's. I lost 4 tenths and 3mph at the top end. 60ft was the same...

That is good and bad news... At least now you know and everyone else. Dont think i will be getting 4.56's may just stick to 4.10's.

Let us know if anything changes.

 

[BlackRamHemi]

x2,
High DA is one thing, but if it fell on its face going into overdrive before the traps, that's going to hurt you every time.

Run it a couple more times,
1) try using 2nd prime (manual shifting)
2)see if you can borrow a taller DR from someone
3) take note of what gear/rpm your at when your approaching the finish line each time.

I think a 4.30:1 would be the answer, but that isn't going to happen unfortunately
So you may have to go 4.10's or change tires to a 30".

 

[KarateManAZ]

We had some nasty DA/Temps last Sat. Normally if I correct my times on dragtimes it bumps 1 tenth off but I corrected it and it took about 4tenths off... So honestly I don't think I gained anything or lost anything. I was also running with more weight than the 12.5 slip, So I'm not totally bummed out/let down by the gears but I have to say was expecting more from the 4.56's

 

[snrusnak]

Don't worry, you still have one of the coolest rams around

So did you have 3.55 or 3.92 originally? You'd probably be better off with 4.10's or if you already have 3.92's laying around then just go with that...

 

[KarateManAZ]

I had 3.92's before the swap.

It's funny At the track the truck was feeling a little slugish all night but on the way home at 2:00am it felt like a completely diff truck. The Temp had dropped 20+ degrees when I drove home from my buddy's house.

 

[snrusnak]

That is strange. A sluggish feeling due to a temperature drop should be more noticeable with higher gearing than lower gearing...or at least that makes sense to me.

 

[hemiexp04]

Did you ever decide what gears your gettin? Im sure im going to be changin mine soon so it would help to see whats best. Have you tried lookin for some 4.30s? Idk what ratios are available

 

[BlackRamHemi]

4.30 would be a no-brainer, but that's not an option for a Chrysler 9.25 diff.
It all comes down to the number of teeth on the pinion in relation to the number of teeth on the ring gear.

as a result I'm afraid I'm faced with settling for 4.10's
or going to 4.56's and needing to buy 4 new DR's that sit about 29"-30" tall.

The key is definitely to stay out of 4th gear before hitting the traps.

I cant do any track testing or detailed calculations until I get back to the track,
I need to know my exact RPM's at the line but our track doesn't open until April 27th.

My effective gear ratio with 3.55's and 27" DR's is about 4.30:1
I believe I'm 4400-4600 rpm in 3rd gear, but not 100% sure.
If I can get to 5800 in 3rd with 4.56's and my current tires, that will be the determining factor.

If I'm wrong and I shift into 4th. I'll be in overdrive at 3000 rpm at the traps, and have to shop for new tires.

I may scrap the entire gear swap and just add a rear LSD, then spray it
Why struggle for mid/low 13's when I can get 12's for less $$$.

 

[Darkknight3829]

4.30 would be a no-brainer, but that's not an option for a Chrysler 9.25 diff.
It all comes down to the number of teeth on the pinion in relation to the number of teeth on the ring gear.

as a result I'm afraid I'm faced with settling for 4.10's
or going to 4.56's and needing to buy 4 new DR's that sit about 29"-30" tall.

The key is definitely to stay out of 4th gear before hitting the traps.

I cant do any track testing or detailed calculations until I get back to the track,
I need to know my exact RPM's at the line but our track doesn't open until April 27th.

My effective gear ratio with 3.55's and 27" DR's is about 4.30:1
I believe I'm 4400-4600 rpm in 3rd gear, but not 100% sure.
If I can get to 5800 in 3rd with 4.56's and my current tires, that will be the determining factor.

If I'm wrong and I shift into 4th. I'll be in overdrive at 3000 rpm at the traps, and have to shop for new tires.

I may scrap the entire gear swap and just add a rear LSD, then spray it
Why struggle for mid/low 13's when I can get 12's for less $$$.

I found a 4.10 rear end setup for 1200$ on the online mopar store. Went by the dealership to confirm what exactly it was that I would be receiving because it seemed cheap. And turns out to be everything you need for a gear swap. 1200$ aint bad. Im running 3.55s as well. I plan on swapping to 4.10s as my last mod on my truck.

I run the exact same tire as you when at the track. MT drag radials. just a different wheel.

Now that i saw those wheels (Your track wheels) on your ram. I may have found the set of wheels ive been searching for to put on mine :smileup:

 

[Darkknight3829]

Also what program will they be using to do the custom tune on the Dyno? That is what i was going to do but a buddy of mine from the performance shop said the program has not come out yet. I believe he called it the HP TUNE

 

[snrusnak]

HP Tuners has been saying they will be releasing tuning for chrysler for years. I am becoming doubtful it will ever happen, however when I emailed them they said they are in fact still planning on releasing it.

I believe BRH will be using diablo/CMR.

 

[BlackRamHemi]

Good deal,
I remember looking into that 4.10 rear diff shortly after getting my Truck,
unfortunately the shipping to Canada would negate any savings,
and I've still got a front diff I'd have to match.

I'm looking at $1800 parts (Gears,Locker, bearings etc.) Front and Rear
and about $1500 in labor :158:

Diablo Tuners use Chip Master Revolution software (CMR)

Link: http://www.diablosport.com/index.php?module=htmlpages&func=display&pid=8http://www.diablosport.com/index.php?module=htmlpages&func=display&pid=8]

 

[hemiexp04]

4.30 would be a no-brainer, but that's not an option for a Chrysler 9.25 diff.
It all comes down to the number of teeth on the pinion in relation to the number of teeth on the ring gear.

as a result I'm afraid I'm faced with settling for 4.10's
or going to 4.56's and needing to buy 4 new DR's that sit about 29"-30" tall.

The key is definitely to stay out of 4th gear before hitting the traps.

I cant do any track testing or detailed calculations until I get back to the track,
I need to know my exact RPM's at the line but our track doesn't open until April 27th.

My effective gear ratio with 3.55's and 27" DR's is about 4.30:1
I believe I'm 4400-4600 rpm in 3rd gear, but not 100% sure.
If I can get to 5800 in 3rd with 4.56's and my current tires, that will be the determining factor.

If I'm wrong and I shift into 4th. I'll be in overdrive at 3000 rpm at the traps, and have to shop for new tires.

I may scrap the entire gear swap and just add a rear LSD, then spray it
Why struggle for mid/low 13's when I can get 12's for less $$$.

With you haveing 4wd i would probably ditch the gear swap and just do the lsd. Its really not worth the money. You could do a cam swap, stall or somthing and still be cheaper. With you crossing the line at that rpm i would try some spray and see what happens maybe a 100 shot and youll be deep in the 12s and if you have problems with rpms at tht point change tires or smthn. just my .2

 

[InDeepWaterBlue]

I found a 4.10 rear end setup for 1200$ on the online mopar store. Went by the dealership to confirm what exactly it was that I would be receiving because it seemed cheap. And turns out to be everything you need for a gear swap. 1200$ aint bad. Im running 3.55s as well. I plan on swapping to 4.10s as my last mod on my truck.

I run the exact same tire as you when at the track. MT drag radials. just a different wheel.

Now that i saw those wheels (Your track wheels) on your ram. I may have found the set of wheels ive been searching for to put on mine :smileup:

Does that include the LSD as well or is that just the gears, I'm a slight newb to this whole rear diff thing, I want to swap out the 3.55's for the 4.10's with a limited slip so I'm not peg legging it anymore.

 

[BlackRamHemi]

Does that include the LSD as well or is that just the gears, I'm a slight newb to this whole rear diff thing, I want to swap out the 3.55's for the 4.10's with a limited slip so I'm not peg legging it anymore.

It's the entire R/T rear axle assembly, all ready to bolt in
Housing, Gears, LSD Carrier, Axle Shafts already assembled.

I think all you do is swap your own brakes over.

http://moparonlineparts.com/repair-parts.php

third selection on this page...

The axle change is a pretty easy for the average shade tree mechanic to swap, just a driveshaft, control arms, track bar, brake lines.
installing and setting up a ring/pinon takes a skilled tech that can charge you more in labor than the price of the gears/carrier/install kit and bearings alone.

If your 3.55 rear axle is still fairly new, you can sell it to recoup some of your cost,

 

[chefred112]

swapping out the 3.55's for any other gearing upwards is a no brainer... doesn't make sense to mod everything else when the gearing should be a part of the list...

 

[Darkknight3829]

Does that include the LSD as well or is that just the gears, I'm a slight newb to this whole rear diff thing, I want to swap out the 3.55's for the 4.10's with a limited slip so I'm not peg legging it anymore.

Exactly..
It's the entire R/T rear axle assembly, all ready to bolt in. Just have to transfer rotors, brakes i believe. So you wont peg leg it anymore with the 4.10 setup. The 4.10 comes on the R/T. Thats why he is saying its the R/T package. The 3.92 is an option on regular Ram 1500's. I think some 1500's come with a 3.72 (Dont catch me lying i am unsure of this)

 

[Darkknight3829]

Good deal,
I remember looking into that 4.10 rear diff shortly after getting my Truck,
unfortunately the shipping to Canada would negate any savings,
and I've still got a front diff I'd have to match.

I'm looking at $1800 parts (Gears,Locker, bearings etc.) Front and Rear
and about $1500 in labor :158:

Diablo Tuners use Chip Master Revolution software (CMR)

Link: http://www.diablosport.com/index.php?module=htmlpages&func=display&pid=8

Oh yea haha shipping plus labor would kill you. Didnt take that into consideration. Since the mopar dealership is here I can just pick it up an do the install myself when i get around to getting myself the 4.10's.

Wow i was never introduced to this before. Am i seeing this right. 2500$? Or does the performance shop your going to already have this? That is pretty cool. I didnt know of this program.

 

[Darkknight3829]

swapping out the 3.55's for any other gearing upwards is a no brainer... doesn't make sense to mod everything else when the gearing should be a part of the list...

Gearing is the last on the list. Because of $$$ & the time it will take me to do the install myself

Definitely a MUST If i want to reach my goal or rather have a complete build.