I'm trying to figure out if I should use a 3 rib bus transmission in my 4 seat rail. My biggest fear is the low gearing in the 3 rib. The rail is going to see 80% street use and 20% trail riding. I'll be running Goodyear 31x15.5 terra tires or 31x10.5-15 MTRs or a little of both on and off road. I don't think I'll ever exceed 65 much but I do want to be able to cruise comfortably @ 60mph. What rpms will the motor be running? I currently have a single side cover type 1 transmission and I can already tell 1st gear is way too tall for off road. If it wasn't for that I would save the cash and use the type 1 trans. My motor will be a 1641. So how is the 3 rib on the pavement?

I had a 5 rib in my 4 seat buggy and it had 31"-32" tires. It revved pretty high on the highway but it was doable. It was fine around town. Now I have a 094 6 rib with a higher gear and 35" tires. I almost wish I had the slightly lower gear with the taller tires. 4th gear with the 6 rib is for 40mph and higher or it's just putting.

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"Obstacles are those frightful things you see when you take your eyes off your goal." -Henry Ford

For the street i would plrobibly like a Car tranny like 3.88 or a 4.12 IMO

I have 3.88 gears now. First gear seems very tall for off road. Seems i can't have best of both worlds. Gear calculator says 61mph would be 3k on 30" tires. 5 rib has higher gears than 3 rib. Im really at a loss on what would be best. My 2 seater has 4.3x gears and its pretty good. I off road about 4 times a year at haspin and other places. The 4.12 trans would be a little better but Im not sure that little of change would justify the swap. I just need to run 60ish mph without motor reving sky high.

I had a rail with a 1641 with a car trans and 31's on flat ground done ok 60 mph was max and a hill would kill it. The one I have now when I got it was a 1600 with a 3 rib I really liked it also has 31's but at 60-65 it's turning 3600. Thinking 55 was around 3k. I'm running a ecotec with 6 rib now and same tires with the power it's great on the street most of my buggy time is also street riding. Over the summer I got a set of street tires in 31's felt like I picked up a 100 hp with them over my tsl.

I would run the 3 rib you will like the low gears in town and on long tall hills.

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My ECOTEC swap http://www.woodsbuggy.com/index.php?option=com_jfusion&Itemid=10&jfile=viewtopic.php&f=23&t=11394

Thanks for the info! 55mph 3k? The gearing calculator says 61mph @ 3k with 30"tires. i used 5.37 final and .82 fourth gear. I think on a heavy 4 seat reving higher would be good on stockish motor.

It will be fine. The stock VW bus would run 60 with little short tires. The motors were designed to turn the RPM and will actually cool better. With the smallish engine you have you would be VERY unhappy with a car trans.

Thanks for all the replies. I guess I didn’t think of it like that. VW must have thought it was ok to spin 4K for extended amounts of time with 26"ish tires. Being a stock motor I should haven’t to worry about anything. My current light weight 2 seat rail has 31” tires and stock motor and its ok with 4.3x gears but doesn’t take much of a hill to kill speed. Figure a big 4 seat loaded with people spinning 3+K @ 60MPh would be a good thing.

Run the 3 rib for a while and see how you like it. If it doesn't do what you want, change it to a 5 rib later down the road. The 4.86 in the 5 rib would be about perfect for what you want to do in my opinion.

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Buy the best and cry once.

Well Drew's off road hooked me up with a nice refurbished 3rib. Got two bus CVs machined and going to use two bug CVs for outer. Drews is awesome! It was first time in a buggy shop and I went hog wild! Had to make three trips to car to carry everything! Wallet got way thinner that day lol