Freeway Flyer Trans vs Std Trans

I thought the "Freeway Flyer" 3.88 ring & pinion vs the standard 4.125 ratio would give an extra 10 mph at 3000 RPMs which is probably worth the $1k cost (along with stronger side plates and welded gears). A side by side chart (see below) was posted on SAMBA that indicates more like a measily <1 MPH gain at 3k RPM and about 2 MPH at 5500 RPMs. Seems I have a "Free" way flyer in the '74 trans I recently got. Is it worth effort to have stronger side plate added and the 3 & 4th gears welded (for use with a 1641 cc engine)?

With a mild 1641 it's not necessary. S stock 3:88 is fine, you'd have to do a lot of clutch dumping to justify the addional expense. ~Alan

Notice that 1st, 2nd and 3rd gear ratios are the same in both cases. With a smaller engine displacement - less torque - the use of a 4.12 R&P would give slightly better performance in lower gears, possibly allowing you to better keep up with traffic (damn those new Kias are quick!).

My "freeway flyer tranny" has a 3.88 R&P combined with a .89 4th gear, but I have a larger displacement engine and corresponding more torque.

David - what's your speed at 3k RPMs? Chart says I'd expect about 62-63 MPH - 66-67 MPH preferred. I do have lightened flywheel and Counterweighted crank (Engle 110 and dual Del'orts) so hoping it run up smoothly.

One of the trans ('73?) has extra electrical switch (in addition to BU light) in nose cone area - any idea what that is? It's not on the '74.

David, I have the same fourth and a similarly large engine. I love the combination.
Wolfgang, that'd be about (pretty much exactly) 60 mph.
Alan Merklin drove the crap out of the Hoopty on the highway at Carlisle this year. He didn't ask about the gearing, but it's probably because he couldn't articulate anything with that big SEG on his face. He looked like a South Park Canadian; I thought the top of his head was going to fall off backward.
Larry (or someone similarly versed) can probably put the right years on the gears, but first came from a Bug, second from a 912, third from an early 911 and fourth came from a Bus.
They're all pretty well synchronized, but you have to go back down through second to get into first when decelerating -- or in order to take off from a stop from neutral.
First's kind of finickey about that. Same with reverse.
I don't quite know why -- but if you're taking off, it's bang, bang, bang ... wait a bit while third winds out, and then Bang. Smooth as silk. She LOVES third.
That really tall Bus fourth gear is good for a few extra miles an hour over what she used to do with a standard Bug gearbox.
I have a specific-year ('63?) Beetle transaxle case, in order to put the Bus clutch, short axles and the super-diff in there. We looked around for quite a while to find a donor.
What a difference.