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Stroker vs ratio change

Posted: June 25th, 2013, 11:30 am
by Gas Guzzler
Hey guys, although I'm new to the forum, I've been lurking the site for months.

I'm a xj Cherokee owner in South Africa and I recently fitted 31s to my jeep. The increase in tire size has had a huge effect on the auto transmission, so much so that I'm considering an expensive ratio swop. However, before I do that, I was wondering what everyone's thoughts are on a ratio change versus the stroker route.

In other words, will the stroker conversion solve my inadequate 3.55 ratio problem, or will I still have to perform the ratio change even with a stroker motor? I can't afford to do both mods, so I'd like to pick the most effective. Personally, I'd rather spend the bucks on more torque than diff gears.

Your thoughts would be greatly appreciated.

Re: Stroker vs ratio change

Posted: June 25th, 2013, 1:57 pm
by TR1Hemi
I am in the same situation, but I was going to build a stroker anyway. It will be interesting to here some opinions. I am not going to do a gear change until I see how the extra torque helps the situation out.

Re: Stroker vs ratio change

Posted: June 25th, 2013, 7:07 pm
by IH 392
My Wrangler has 31's on it with the 4.0, it had 3.55's, I swapped in 3.73's and the only reason I'm not dissatisfied with the gear swap is my mileage stayed exactly the same. :huh:

Re: Stroker vs ratio change

Posted: June 26th, 2013, 5:35 am
by cruiser54
My 88 XJ with a 4.0 and 31s works great. Runs as strong as my 90 MJ with stock sized tires here at 5,000 foot elevation.

Re: Stroker vs ratio change

Posted: June 26th, 2013, 10:49 am
by Cheromaniac
Going from 3.55 to 4.10 axle gears will increase torque multiplication at the wheels by ~15%.
Going from a stock 4.0L displacement to a 4.6L stroker displacement will also increase average torque by ~15% (bigger increase at lower rpm, smaller increase at higher rpm). If your existing engine's tired, a stroker rebuild would make more sense than swapping axle gears.

Re: Stroker vs ratio change

Posted: June 26th, 2013, 11:09 am
by Gas Guzzler
Thanks cheromaniac. Those are interesting figures. That's pretty much what I was thinking. The great thing about a stroker motor conversion is that you get a brand new motor with the stroker. It seems like better value for money that a ratio change.

Re: Stroker vs ratio change

Posted: June 26th, 2013, 3:58 pm
by shawnxj
well my stroker seems to like the 4.10's and 35's. i was thinking about doing 4.56's but there's no need

Re: Stroker vs ratio change

Posted: June 27th, 2013, 2:11 am
by Cheromaniac
shawnxj wrote:well my stroker seems to like the 4.10's and 35's. i was thinking about doing 4.56's but there's no need
Yup, that makes sense, and the OP's 3.55s and 31s should work well with a stroker.