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Should I go with 39.5" IROK or 42" IROK ?
The current specs:
318 engine, not a lot of power to spare!
TF727 tranny with 2.45 1st gear ratio.
NP 208 transfer case with 2.6 low range.
Old gearing 4.56/ new gearing 5.86
Old tires 38.5 tslsx
So, 2.45* 2.6* 4.56 = 29:1 crawl ratio
2.45* 2.6 * 5.86 = 37:1 crawl ratio
These are without taking into consideration the torque converter.
There is about a 28 % gain in crawl ratio.
There is about an 8 % difference between the 38.5 actual tire diameter and the 39.5 and about a 14 % difference between the 38.5 and the 42" so, I should feel some overall gain, right???
I really want the 42" for the extra ground clearance but without some modifications to the engine I am not sure if I should just get the 39.5" IROK and be happy?
I have come to really love the rock crawling the most so the ground clearance is becoming an issue but without the reliable power to turn the tires it creates a safety issue. Could do propane or add fuel injection i guess but there goes lots more money.
Comments please, and be honest!
The current specs:
318 engine, not a lot of power to spare!
TF727 tranny with 2.45 1st gear ratio.
NP 208 transfer case with 2.6 low range.
Old gearing 4.56/ new gearing 5.86
Old tires 38.5 tslsx
So, 2.45* 2.6* 4.56 = 29:1 crawl ratio
2.45* 2.6 * 5.86 = 37:1 crawl ratio
These are without taking into consideration the torque converter.
There is about a 28 % gain in crawl ratio.
There is about an 8 % difference between the 38.5 actual tire diameter and the 39.5 and about a 14 % difference between the 38.5 and the 42" so, I should feel some overall gain, right???
I really want the 42" for the extra ground clearance but without some modifications to the engine I am not sure if I should just get the 39.5" IROK and be happy?
I have come to really love the rock crawling the most so the ground clearance is becoming an issue but without the reliable power to turn the tires it creates a safety issue. Could do propane or add fuel injection i guess but there goes lots more money.
Comments please, and be honest!