Redline

[Swagger]

Is there any way to extend the factory redline on a stock 4.0 a couple hundred to a thousand RPM's?
I know on my old mustang, (1968 302, stock GT HP302 motor) when i changed the distributor from a points style to an electonic set up, i gained almost 1600 RPM's of power band. I know that specific scenario doesnt apply to a modern jeep engine but is there anything else that can be done.

Also, NV4500 or AX-15? which one is the best bang for the buck. i wanna go manual, rolling 37's i have to stay geared down to 4.10's or near that to keep my RPM's from being rediculous at speeds over 45mph? So to gear up to 4.56's or 4.88's, i i want/need to do a tranny swap so i dont end up grenading my 32RH factory 3speeder.

[Axle]

NV4500

[Swagger]

So expensive. Worth it?

[Mr Rock]

O

NV4500

X2 it is a little stronger than the AX15.

[skibum]

I think the only way is with an aftermarket tuner like Superchips to gain more RPM"s. There are other options but you will need to do research.

The AX15 is a great trans but if your going to go bigger with your rig some day than it might be worth it to go with the NV4500.

[gearhead1985B]

I know a stock 4.0 will throw a rod at about 6K so why would you want to extend the redline untill you on the virge of catostrofic failure and a 4.0 will make max power at 4500 so i think it is better to play it safe and  leave the red line where it is at stock IMHO there is no real gain in increasing the redline rpm

[Flex]

I agree with Adam ppl smarter than us put it where they did for a reason

[zjchef25]

I agree with Adam ppl smarter than us put it where they did for a reason

i second this

[kirksjeep]

Mustangs make horspower at high RPM, Jeeps make torque at low RPMs.  Unless you plan to drag race your Jeep, I can't see a reason to go past the red line.  Off Road I rarely make it over 3500RPM, now Rock on the other hand.....

NV4500 all the way.  The AX-15 is a medium duty transmission.  On my list of future upgrades.

[Swagger]

I think the point of my question might have slightly been under explained. Its not the horsepower i was actually after. It's more of a "how do i get a larger range of safe operation out of my motor" type question. I understand the whole horsepower vs. torque thing. but what i was wondering was more along the lines of a range of motion type deal. with a manual tranny, its not such a big deal, but with the auto, i just cant seem to get to comfortable with the fact that at highway speeds, i'm bouncing 2500 rpm's. It just feels like if there were more room for the motor to safely run its power band, then it wouldn't be as much of the load on the engine. i dont know at this popint. maybe i'll just shut up and do a tranny swap and get it over with. plus having the NV4500 in there, will definitely make the Cummins swap down the road a little less painful. Maybe by about 5%.

[Flex]

if ur planning on swapping a bigger engine in later then put a full size tranny in now, i would run  a FSJ tranny like a 727 Torque flight this will bolt up to a inline 6 so it works pretty nice. this tranny is comparable to a TH400 if u wondering how strong it is.

[gearhead1985B]

The 727 will not bolt up to a cummins but a turbo 400 will i forget what gears and tires you are running that will have a grater affect on highway rpm than a tranny swap

[Swagger]

right now, its a stock 3 speed RH32 jeep auto tranny, D35 w/373's and 33's. in the future (spread out over the next 2-3 year, 5 or so till the cummins swap), I already have the 8.8 to go in it, i'm looking for a HP44 for the front, gonna gear it to 4.88 (or something close), lock it, and roll 37's on hummer H1's, and now i'm thinking that a tranny swap is the next thing i do before anything else. i know for a fact, that having those extra two gears are probably the only way to reduce my final driveline RPMs. so thats where i'm at. the reason i'm having to/wanting to wait, is, i'm planning on going a little more than crazy on this, and i only plan on doin it once. Gonna stretch it to a 103" +/-2" wheel base.  No fender laws in texas is a beautiful thing. tube fenders, comp corners and with the backspacing on the wheels, probably gonna be almost like running full width axles.

[Flex]

i wouldnt call 3/4 ton axles crazy u should think about doing it right the first time and going with one tons.

[Swagger]

I know, I know.  I've been thinking the same thing since i bought the 8.8.  i think i could probably sell it for more than what i paid for it. I really like the idea, and I've been trolling through pirate4x4 for weeks now, drooling on my key board (see project "Copperhead") and I've been noticing how relatively easy (just time/$ consuming) it is to do most of the work. Builder components, kits, and fab friendly parts make it all possible, even on a fairly small budget. Problem is, a welder, cutter, and one tons cant seem to squeeze their way into it right now. Even with the awesome deals I've found online and through friends, i just cant seem to make them appear awesome to my non-jeep friendly wife.  I know, it's blasphemy, but hey, what can i do? i got her before i got the jeep, so.....