Topic: Will I have decent acceleration?

[mack90]

I have a big pile of stuff ready to put on my 1998 manual tranny 4 banger jeep, and was just wondering what I should expect.  4.88 gears, 33x12.5 tires, winch body armor tire carrier, kilby skid, jeeperman side bars, electric cooling fan, firepower ignition, freeflow cat/exhaust.  This is a little weight, should I expect no acceleration at all with these added?  I have a dana 44 axle I could put in too.  How much weight difference is the 44 over the 35?

[Jeffy]

I have a big pile of stuff ready to put on my 1998 manual tranny 4 banger jeep, and was just wondering what I should expect.  4.88 gears, 33x12.5 tires, winch body armor tire carrier, kilby skid, jeeperman side bars, electric cooling fan, firepower ignition, freeflow cat/exhaust.  This is a little weight, should I expect no acceleration at all with these added?  I have a dana 44 axle I could put in too.  How much weight difference is the 44 over the 35?

The gears will help A LOT.  That's going to be your #1 upgrade.  Even with all the extra weight, it should be OK.  I'd go ahead and install the D44 if you're going to be doing gears anyway.  You'll probably see a larger drop in performance from poor gearing and poor aerodynamics then with added weight.

[mack90]

Thanks for the info.  I am building this jeep for a life long farm/play vehicle.  I noted taking my rubicon out to the farm it would really suck down some fuel.....so now a four cylinder.  Any idea on fuel economy with this set-up?

[Jeffy]

Thanks for the info.  I am building this jeep for a life long farm/play vehicle.  I noted taking my rubicon out to the farm it would really suck down some fuel.....so now a four cylinder.  Any idea on fuel economy with this set-up?

That really depends on what your jepe currently gets and how you drive it.  I get around 16-18mpg with my 35's normally.  If I keep the speeds down to 60-65mph on the highway and follow behind a large truck, I can still get into the 20's.

[Bounty Hunter]

With 33" and 4.88's your power and mileage will be down just a little bit from stock, but liveable.

[garydubf]

I'm Get 16-18 and hit 20 on long flat drives w/out a e-fan.  4.88's and Heavy ass 35 Toyo's.  Power wise is relitively close to stock but in a head wind forget passing or keeping up with the flow of traffic.  Short of super charging I really don't think that you'll ever be pleased with the power out put of the 2.5 without some major mechanical mods and at least 5.13's.  If I had it to do all over again with the same money I'd save for the V8 swap and dana 44's, which is the direction I'm going now.

[bestos]

u getting aluminum wheels or steelies,

rotational mass is a factor, aluminum is less than steelies.

steelies slow my acceleration

[cmgorman94]

I have 35s and 4.88s, I usually get around 16 mpg.  If you have a D44, either put it in or give it to me.  If you have the better axle, why not use it?

[jfrabat]

I have 35s and 4.88s, I usually get around 16 mpg.  If you have a D44, either put it in or give it to me.  If you have the better axle, why not use it?

cmgorman94, I disagree with your evaluation; I think he should give it to ME!!!   

[mack90]

Thanks for the information.  I was hoping to get 18ish with 33's and 4.88's.  The main thing I wanted was better fuel economy at the farm which is usually around 10mph driving.  My rubicon would go through a 3/4 a tank a day at the farm.

[dexetr30]

Doesn't matter if it's a 2.5 or a 4.0, Jeeps are not economy cars. The 4 banger doesn't do much better than the 6 when it comes to mpg.

[bestos]

like i said above, i hope you are getting aluminum wheels, that will save the mpg some.

[mack90]

My plan is aluminum 33 10.50's for the street, have a set of 33 12.50 swampers on beadlocks for the farm.  I was basing the mileage on the 4 cylinder getting better economy in town than the six.  I'm hoping it will apply at lower speeds at the farm too.

[Jeffy]

My plan is aluminum 33 10.50's for the street, have a set of 33 12.50 swampers on beadlocks for the farm.  I was basing the mileage on the 4 cylinder getting better economy in town than the six.  I'm hoping it will apply at lower speeds at the farm too.

If you keep the speed down it should do a bit better then a comparable 6.  When you start driving faster say over 55mph, you are at a big disadvantage because of the lack of available torque from the engine.  Wind resistance starts becoming a factor at around 40mph and grows exponentially as the speeds increase.  Then is when you're flooring it to keep speed and that just kills your mileage.  This is why proper gearing is important especially so for the I4.

[BOOGIE444]

I have 33 x 12.5 and 4.88, no other mods that add weight though.  My performance is almost identical to stock.