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gearing suggestions, 4.6 stroker on stock size tires

GrimmJeeper

NAXJA Forum User
Location
Gardena, CA
I'm getting to the point of my 94 2 door build where I need to start planning out my gearing. It's a 94 4x4 (231) with an ax15 in it. I'm having a 4.6 with a big cam built for it, 99+ intake, gasket match ported head and intake/exhaust, probably going with a borla header and a bored throttlebody. it's going to stay stock height and on stock size tires with ar23 wheels.

it's got 3.08s in it now, but I'm worried with the stroker in there I'll run out of gear on the top end. Any suggestions?
 
According to my calculations red lining the ax-15 in top gear on stock tires gives you about 140-150, I cant remember the exact amount. FWIW, my 4.6 ax-15 has 3.55's on stock tires and I think Gradon is running similar.

I checked my math: 235/75/15, ax15, 3.55 gears and 5200rpm you'll be doing 159.29mph. Same everything else with 3.08 is 183. I think you'll have enough top end, if I'm understanding you properly.
 
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that's kind of what I was hoping to hear, I have a brand new in box set of 3.55 gears for my rear axle already sitting here that I bought when the axle on my 95 blew itself apart after jumping. I swapped that axle out completely so if I can use the gears I already have here and just regear the front that will save me a bunch of money.
 
it's got 3.08s in it now, but I'm worried with the stroker in there I'll run out of gear on the top end. Any suggestions?

I also have a 4.6 stroker, stock 27.4" tires, stock height suspension, AX15 tranny with NP231 TC. With the stock 3.07 axle gears, the gearing is just about perfect so I wouldn't mess with it. I can hit the 5200rpm rev limiter in 1st (36mph), 2nd (59mph), and 3rd (96mph). My 1/4 mile trap speed of 94.4mph is near the top of 3rd gear. In 4th gear I hit the top speed governor at 116mph with the engine at 4350mph, and I also hit the 116mph top speed governor in 5th with the engine at 3450rpm.
 
If I had a 5-speed jeep on stock tires that I wanted to be fun on the street I would run 4.10s and a 242 tcase
 
I have 255/60/15s which are 27"(stock is 28"?). When the tires need replacing, I'll look for 255/50/17s, also 27" tall, on 17x8-9"s, that stick out a little more to widen the track and lessen the body roll(a little stiffer sidewall). At first, I ran auto 3.55s w/ Auburn LSD and it was a great combo with the ax15. I wore out the LSD during the "Snowcopalypse" when I was out in the snow everyday w/ my 2wd for 2 weeks straight. When I got my diff exchanged(Auburn has an awesome program--replacement was ~$130), I decided to go with 4.10s. I essentially have a 4.5 speed now as 1st is over in 3 seconds. Now with an AW4, maybe its not so bad but cruising 75-80mph(my typical beltway speeds) in 5th is at 3Krpm. My ideal ratio for stock tires is 3.73 and I'll get them somewhere down the line. With the 3.55s and a passenger, my brother paced me at 136mph on his '08 FZ6 and I could've slowly hit 140mph w/ another mile, but not much else. At 120mph, you feel the wind resistance pick up exponentially. I do have thoughts of the next stroker I build going into a 2dr ax15 242 rally jeep.
 
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If I had a 5-speed jeep on stock tires that I wanted to be fun on the street I would run 4.10s and a 242 tcase

That wouldn't be fun at all 'cause the intermediate gears would be uselessly short (maximum 27mph in 1st, 44mph in 2nd, and 72mph in 3rd), and 75mph in 5th gear would be at ~3000rpm so gas mileage would suffer.
Even with the stock 3.07 gears, I have plenty of torque in 5th gear for overtaking and can cruise at 75mph with the engine at ~2200rpm, delivering excellent gas mileage.
 
Even with the stock 3.07 gears, I have plenty of torque in 5th gear for overtaking and can cruise at 75mph with the engine at ~2200rpm, delivering excellent gas mileage.
qft

my old stroker had 3.07s and an AX15 but i was also running smaller than stock tires. it scooted pretty good. didnt notice much of a difference when i put on 30x9.50s. i think youd be more than happy with 3.55 or if you get lucky and find 3.73s. but i wouldnt go any lower than that.
 
Yes but launching in awd (full time) in a 242 case is soooooooooooo much fun

Fact.



I setup my 95 2dr 4.0/AX15 with a 242 and 8.8/HP30 w/3.55's . I ran it for awhile with stock 225/75/15's and it was a freakin blast!!! Ive done some hard launches in FT, you know, just to try it out and all. The jeep grabs and pulls hard, with good shifting it'll hook up nicely. I did lose some top end and normal driving on the highway slowed a few MPH to help keep the gas mileage happy. I could cruise around town in 5th at ~40mph with no problems. It had plenty of torque to recover even when trying to bog it down.
 
maybe I'll consider swapping the 231 for a 242, I've launched in 4hi in the rain before on the 231, there's nothing like hooking up at a light in the rain when the honda with the massive spoiler next to you just spins and doesn't move :D

Thanks for the input everyone, hopefully this thread will be useful for anyone else in a similar situation down the road.
 
maybe I'll consider swapping the 231 for a 242

I highly suggest it for a street jeep. Mines got a H&T and Ive beaten the crap outta it with no problems. Having FT was awesome for rainy/stormy roads and in the snow it was just magic. I used to hate driving my manual in poor conditions but thats since changed, Ive become a 242 fan.
 
I run a242 in my dd 89 limited.....lemme tell ya great heater great ac cumphy leather seats and a 242 t case is great. I run whatever metric size is a 30.5 duratracs and I LOVE the rain and snow driving
 
it only rains 3 or 4 days a year here and no snow, so i'd be more interested in the dry launch potential to shut down the sideways hat subi drivers :D
 
I dragged a modded WRX 2-3 lights out of DC on 16th Ave one night and they were a lil faster(they gave me the rock sign afterwards), so a 4-wheel launch would've definitely helped.
 
That wouldn't be fun at all 'cause the intermediate gears would be uselessly short (maximum 27mph in 1st, 44mph in 2nd, and 72mph in 3rd), and 75mph in 5th gear would be at ~3000rpm so gas mileage would suffer.
Even with the stock 3.07 gears, I have plenty of torque in 5th gear for overtaking and can cruise at 75mph with the engine at ~2200rpm, delivering excellent gas mileage.

Dr. Dyno, I thought you were a performance guy?

Those gear change intervals sound fine to me, and 3KRPM on the highway won't do anyharm to a 4.0 or stroked 4.0 at all. Slamming gears and hauling ass seems pretty reasonable to me lol.
 
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