Just wondering if anyone knew of headers available for the 3.7L models. K&N Intake, Exhaust, and Jet Chip still dont give me the torque I want with my 32" toyos and lift.
adamag25 said:I have heard of many people with the 3.7 in the new 4 door JK wrangler. They love the engine for its fuel economy, its quiet, and very dependable. They don't like that no matter what they do to it it won't make the torque they want. The only way they can get the performance offroad they need is to swap gearsets. The lower gear set isn't great for the highway but it does help get that engine to perform. Do you know your gear ratio in the axles?
Not that im purposely trying to correct you but 4.10 gears on a 4 cyl and 35's would be a complete dog. You would need some 4.88's in the axles. Its also a lower gear ratio, just a numerically higher number.adamag25 said:my mistake, despite that I doubt that the .1L will make a huge difference. When it comes to a lift and tires, axle ratio has more to do with torque than engine performance. I agree with 4.7 the gearset swap will be more effective and less costly to get you to have more power to the wheels. For example look at a old wrangler with a 4cyl and 35's on it. The gearset is probably at least a 4.10 or higher.
Where do you go to get gears installed that would be cheaper to buy both front and rear 3.73 gears and get them installed for under $500-600 dollars. (The cost of headers).4.7commander said:v6 has 3.07 gears in the axle. what was jeep thinking????
but i digress.
just switch out from 3.07 gears to 3.73 gears. it will be cheaper and more effective then headers on a v6
Just trying to make a point. I would only use a 4 cyl for a beater anyway. the 258ci was where it was at!07JeepXK said:Not that im purposely trying to correct you but 4.10 gears on a 4 cyl and 35's would be a complete dog. You would need some 4.88's in the axles. Its also a lower gear ratio, just a numerically higher number.
That's why 4.7 suggested finding a front and rear axle set from a wrecked WK or XK, then it would be a direct swap and configuration in the computer with the StarScan (yes, you have to have the ECU changed too). No one makes aftermarket gearsets for the the front diff in the WK/XK, which is why nobody on the site can go any higher than 3.73 ratio. The junkyard axles should be new enough that they would be covered under the drivetrain warranty since they're still an OEM item. You can do the swap yourself, saving on the labor costs.runit3 said:the main issue i have with doing a gear swap is the labor it's going to cost me. Assuming I had the knowledge of how to do it myself (which I dont) i would also need a fairly sturdy truck lift and/or multiple jacks and stands. (which I do not). realistically headers won't add much in the way of torque by themselves without a substantial computer overall (my stage 2 jetchip may be able to pull some more out of headers). I can also look at pulling the cat out or modifying the baffling. I would also feel more comfortable buying aftermarket gear sets than junkyard hopping because of the warranty that may (or may not) come with them. i would rather have junkyards parts, especially those that come out of abused jeeps, stay out of my truck. If I do get the headers slapped on (seriously considering) I'll be sure to post updates.