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Wed Aug 24, 2016 9:37 am

Hi chaps,

I am tranny dumb and was hoping somebody smarter than I could explain a tranny question.

I am looking at the rancho type one pro street vs. the type 1 pro comp.

http://ranchotransaxles.com/vw-transaxles/

the pro street has:

super diff
aluminum side cover
welded 3-4 hubs
hardened key

The pro comp has all the same but with "close 3rd and 4th gears"

Can someone please explain what the close 3rd and 4th gears does performance wise and is it worth the 300 extra bucks?

I am going to build a daily driver (not racing) with a 2.5 suby engine. And although i know i need a tranny better than the stock VW model, I am unsure what to go with. If there are better options that I am not considering please speak up.

Any help is greatly appreciated.

Wed Aug 24, 2016 9:51 am

I run a Rancho transmission and those guys are smart, honest and can help guide you. Your gearing is going to be different if you are running a Suby but Recommend the Super Beetle 1st for its strength 3.78:1 unless you want to spend for aftermarket like Weddle gears then you may have other choices in strong 1st's. The stock non-close ratio 4th is basically an over drive 4th. So lets say each time you shift from 1st to 2nd and then 3rd it may drop 800 RPM's beteween shifts but from 3rd to 4th may be 1000 RPM drop. If they were all close ratio the drop between shifts would be almost identical. You might want to go for the most you can afford in the strength area if you are running Suby though. All modern cars have close ratio so if you want that experience the buy close; just decide on 1st and 4th then put 2nd and 3rd at even intervals between. If you call them they guide you.

Wed Aug 24, 2016 11:09 am

A close ratio transmission has smaller gaps between gear ratios in favor of acceleration, designed to mimic the gearing spacing in a transmission with more gears. However, unless you are increasing the number of gears, you will lose some top end with the lower (numerically higher) top gear. I don't see why you would want one for a street car, as you will have higher rpms per given speed in top gear, which would make freeway cruising louder and more taxing.

For example, a stock VW Type I transmission would have the following gear ratios: 3.80 first, 2.06 second, 1.26 third, and 0.89 fourth. A close ratio four-speed with different third and fourth gear ratios might be: 3.80 first, 2.06 second, 1.48 third, and 1.04 fourth. Assuming a 4.125 ring and pinion and 165/80R15 rear tire, your engine rpms at 70 mph would be approximately 3,400 rpm with the stock 0.89 fourth gear and nearly 4,000 rpm with the 1.04 fourth gear of the close ratio box. You can play around with various gear and ring and pinion combinations using the gear calculator below:

http://johnmaherracing.com/calculators/gear-ratio-calculator/

Wed Aug 24, 2016 11:31 am

that's makes sense. Thanks for putting it into layman's terms. It sounds like the prostreet will fine and save 300 bucks over the procomp.

Wed Aug 24, 2016 4:18 pm

for some reason those are not cheep any more......

Wed Aug 24, 2016 4:42 pm

Because a lot of the parts are no longer available new. With 50 year old transaxles they are now to the point they need 3 cores to get enough usable parts to rebuild one good transaxle.

Wed Aug 24, 2016 6:17 pm

having done quite a few subaru conversions, you will want to mimic your cruising rpm's to that of a Subaru.

I can do 75 in my bus and turn 3K rpm's. you will want to duplicate that to keep the engine in it's happy spot...too many rpms and you will end up with cooling issues because the water pump is spinning too fast/coolant not staying in the radiator long enough to cool

Thu Aug 25, 2016 5:16 am

I had almost the same question for myself. I'm building a 2332cc buggy and want enough power for the dragstrip, but also a car for easy cruisin. So I asked the guys from Rancho for there advice. They said I could have the best of both worlds when I take a close 3rd and a normal 4th.
Till now I'm completely satisfied with this setup.

Cheers, Peter