OK...here's a question for you old-timers. Have you ever clocked your car with a GPS (or something accurate).
I am trying to determine what the actual not theoretical speeds are at 3000 and 4000 rpm with a 3:88 rear vs a 4:12 rear in 1st and 2nd gear...with 15" wheels and 65 or 70 series tires?
ReV
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I find this calculator predicts actual results very well (car speed measured with GPS).
You can see there's very little difference between a 4.12 and a 3.88 in first and second - the advantage of the 3.88 shows up at higher rpm's in fourth, thus the nickname 'Freeway Flyer'.
You can change any of the variables in the calculator, including tire size, r&p, and individual gear ratios.
Thank you Mitch...I am looking at changing the 1st and 2nd gear combo to something numerically lower vs changing the ring and pinion...this is very helpful !
ReV
That's a cool calculator. Here is my results: Porsche Carrera 915 Box with 195/60 15 front tires.
1st: 35 mph
2nd: 61 mph
3rd: 88 mph
4th: 111 mph
5th: 141 mph
Marty
What rpm?
Trevor 916 wrote a while ago that he runs 3.11x1.96x1.26x.89 (3.88 r&p) and with a CB 140hp 2110 "loves it!". I'm of the understanding that the custom 1st-2nd mainshaft sets are quite expensive ($1,000? I've got an email into Weddle enquiring now) and for $400 (I'll report back on this too) a 3.44 ring & pinion would achieve almost the same thing. The difference- instead of the long 1st, shorter 2nd, slightly shorter 3rd and stock 4th spacing, with the longer (3.44) r&p you'd keep the stock 1st (almost as long as custom mainshaft/r&p combo) and 2nd and shorten up 3rd and 4th where it needs it most (shorter 2nd/3rd and 3rd/4th spacing is fantastic to drive on the street). I'm asking about their 3rd and 4th gear prices too. I used 3500 as the shift point in the comparison as this way you can see the stock vs shorter rpm drops between gears- http://www.teammfactory.com/ge...Transmission+1+%26+2
PS- Since the 3rd and 4th gears aren't stock in trans #2, you could use any gearsets you want- feel free to plug away!
Thank you Mitch...I am looking at changing the 1st and 2nd gear combo to something numerically lower vs changing the ring and pinion...this is very helpful !
ReV
If your engine's displacement is larger than 2000cc then changing the mainshaft 1st and 2nd (if you have the $$$) is the way to go. A 3.44 R&P on a stock trans is still not enough to make 1st and 2nd perfect - I like perfect!
When I hear back from Weddle, Rusty, I'll let you know how much "perfect" costs...
I have a feeling that's what I'll look like when I read how much!
A 3.11 first combined with the 3.44 r&p gives 24mph at 3500 with a 25" tire; the r&p isn't that expensive ($400?), but the 1st/2nd mainshaft is the killer (as I said above, somewhere around $1,000), as it's both gears on the shaft with the mating pieces. Don't get me wrong, I agree with you; it would be just right. It's just a lot of money for 4 extra mph in 1st gear...
I have a new 3.44 r&p and $400 is what I paid for mine.
For those who are interested- Just heard back from Weddle. To sum it up-
3.11x1.86 1st/2nd mainshaft- $479.00
1st idler gear- $219.00,
2nd idler gear- $219.00
slider hub- $103.78
Total cost- $1,020.78
Sportsman 3rd & 4th gear sets with welded hubs- $272.25
113/002 3rd & 4th gear sets with welded hubs-$376.25
The email said these prices are only approximate, as some ratios are slightly more and some slightly less.
billet aluminum type 1 irs superdiff kit for use with 091 (bus) internals- $980.00
Do you think a 2.90 1st, 1.93 2nd, 1.14 3rd, .82 4th with either a 3.88 or 4.12 r&p is too extreme? I sure would like to try that combo with my motor.
Do you think a 2.90 1st, 1.93 2nd, 1.14 3rd, .82 4th with either a 3.88 or 4.12 r&p is too extreme? I sure would like to try that combo with my motor.
I plotted those numbers against what I've got, and against my ideal. I'm running:
1st: 3.10
2nd: 2.07
3rd: 1.30
4th: .93
3:44 R/P, 195/60R15 (24.2")
If I had it to do again (for the 4th time...) I'd have chosen a slightly longer second gear. (3.11/1.93 mainshaft). It really would be perfect for me then.
Laying your numbers (with a 3.88) over mine, and looking at yours by themselves- I think your proposed first and second gear are too close, and that the reach from second to third is too long.
To your point- a strong 2110 will pull the gears, but you won't be drag-racing. 1st is on the edge of being too long- quite the opposite of the stock (useless) first gear. You can pull the 4th, but only if you are a flatlander. I like my gears, but I like to drive long distances at high rates of speed for hours on end. It's too long for most "fun" driving, or if you live in the mountains.
For 99% of the people out there, I'd do:
1st: 3.10
2nd: 2.07
3rd: 1.30
4th: .89
3.88 R/P.
... but you won't be an interstate warrior. The final drive limits you to about 75 mph on the interstate (for long distances) before you are spinning fast enough to have some issues. With my gears (and yours) 80- 85 mph for hours on end is completely doable.
It's my opinion. Your mileage may vary.
When looking at new gear combinations it's best to keep in mind the factory rpm drops from gear to gear; specifically, you can go shorter, but it makes it awkward if you go for longer spacing, especially in the higher gears. Using 3500 as the shiftpoint, a stock gearbox drops to 1900 rpm in 2nd when shifting from 1st, to about 2200 rpm when going from 2nd to 3rd and to 2400rpm into 4th. Any time you play, with a gear calculator, remember those numbers.
I (as well as Stan) recommend even longer than 2.07 for 2nd if using a 3.11 1st; the split you've suggested is too short to be useful in a 4 speed. Using a 1.86 (even longer than Stan's suggestion of 1.93) , the rpm drop is only to about 2200rpm (instead of all the way down to 1900rpm) and that spaces the 2-3 split better and closes up the drop by about 200rpm (so down to almost 2400rpm in 3rd instead of 2200).
Well, I remember my 1600N 59-356A and I really likes the tranny ratios in that one... when I had my IM 2110cc, 3:44 it was good, but I longed for the P ratios. Ray
Do you think a 2.90 1st, 1.93 2nd, 1.14 3rd, .82 4th with either a 3.88 or 4.12 r&p is too extreme? I sure would like to try that combo with my motor.
Looking at the Weddle selection of mainshafts, the longest 2nd gear with either a 3.11 or 2.90 1st is a 1.86, so that limits the selection of 3rd a little, but I think it would still work with a .82 4th and a larger than 2 liter powerplant. Check out the chart in the link; the first is stock gearing. Again, look at the rpm drop from one gear to the next in both combos, which will have the same r&p and tire sizes for a more direct comparison. The 3-4 rpm drop in the 2nd gearset is a tiny bit more than stock but nothing like the drop when pairing the 1.31 with the 0.82, which drops the rpm's down to 2200rpm's in 4th.
http://www.teammfactory.com/ge...Transmission+1+%26+2
The overall first gear ratio in a standard 356 transmission is 13.66. Overall first ratio with a 3.88 R/P and 3.78 first is 14.66. Very close to the same but the VW is a little shorter so would give you slightly more oomph. I would say unless you have a pretty powerful engine your not going to beat anybody across an intersection with 3.44 R/P.
Back in the day when we put 356 normal and super Porsche engines in bugs that had 4.37 R/P's and 3.78 first gears there were very few cars that could leave them at a stop light. That's the kind of performance I'm interested in. I could care less about cruising 80 on the freeway. I hope you all know I don't mean that as a dig, it's just "to each his own".
With all the gear sets available for VW these days, you can have anything you want and the gear sets don't cost a $1,000 bucks apiece like 356.I know a few guys with VW gear boxes in their 356's, they just don't talk about it
I read that last post and thought "YES! THAT's what I had in my '57 VW Oval. Absolute screamer off the line and through 2nd into third - the perfect car for racing between stop lights on Shrewsbury Street in Worcester back in the late '60's/early 70's because the heavier cars couldn't get off the line as fast (or ran out of steam just over 60mph).
From the 1960 Porsche service manual, these are the ratios available when ordering your car; You could go from Autobahn cruiser to stump puller (or short track racer), depending on what you ordered. That last line at the bottom must have had Danny P. in mind......
When I had Sam at Rancho rebuild my transaxle for me last year, I ended up with exactly the same ratios that Stan mentions up above, including the 3:88 rear. It is not quite as quick as it was with the 4:12 rear I had before, but unlike Señor Desert, I wanted a back road and highway cruiser this time - that's what I ended up with for my stout 2,110 and I love it.
Keep in mind that in today’s world a long shift time is anything over 625 ms …something my mentor Ronnie Sox could not touch.
Also an 800 rpm drop between gears is considered a “close-ratio” box.
For me 2nd is too tall for a normal take-off and first is too short…I need a 1:1 4th and an overdrive 5th…much like a Porsche 901 deal…but they do not shift all that fast unless you pull the synchros.
For me any shift is a “time-waster”…which is why the Tesla does as well as it does…
ReV
Gordon, That's why they have Chocolate and Vanilla
My new transmission is 3.88 R/P, 3.75 2.25 1.58 1.22 .89
I wish I would have been interested camera's and pictures back in the 70's. I would have pictures of both of my P wagons. A 64 bug and a 62 Karman Ghia, both had 356 gauges in the dash, 356 brakes, 356 seats and engines. It would cost a small fortune to duplicate one today.
If you are talking about a taller OD 5th. Go to Gene Bergs site. They strongly recommend against using a taller OD than .82. They said the problem is heat with an air cooled motor. You need to keep the revs up to keep the fan spinning and the loads on the engine as light as possible. Slowing down the revs with a tall OD lugs the motor, creates more heat and the slower spinning fan makes it worse. They tried changing the fan pulley to spin it faster and guess what? It used more horsepower and made more heat. I wanted to get a Berg 5 spd but even with 5 gears, they use the stock .82 in fifth. Go on there website and read under the 5 speed conversio, it's really interesting.
With the late ('73) stock Bug gears and the 3.44 R&P Bridget seems to like every gear. First gets above 30 if you want. Or you could skip it entirely. Second is for moving out; tops out at about 65 mph. She runs out of speedometer before she runs out of third (theoretically). 4th would get her to about 145 if we were driving in a vacuum. 3000 rpm is about 75 mph. You can roll-on in that gear and pass anyone who isn't a player. Or you could downshift and be a player at 4300 rpm, heading for peak torque.
Which is not that much, BTW. Maybe 150 ft-lbs. Maybe. But it seems to be there--most of it anyway--at all rpms. The stock Suby really likes everyone between 2500 and about 6000 rpm. Not sure how much higher she will rev with power.
The only downside with the 3.44, as far as performance, is you can't run an LSD with it for some reason.
Ed- you have very tall wheels, I would assume.
Also... I've got a ZF LSD with my 3.44, so it is possible. What you can't run (I don't think) is a Quaife torque biasing differential.
Fpcopo:
I know Berg says that. Gene Berg also though 8:1 was too high for a street compression ratio. I've heard the got to keep the RPMs up for cooling thing since I started in the hobby, but my experience has been quite different. My (old) 2332 running 80 mph and spinning 4K RPM for hours at a time ran significantly hotter than the same engine running the same speed but only turning 3500 RPM. The old saw may prove true if the engine in question is an 85 hp 1776, but with a legitimate 200 hp- the longer the final drive gearing, the better the temps.
When Gene made that statement he was talking about what's needed to survive running legal freeway speeds. And being a manufacturer/retailer, he would never suggest setting up a car to run faster than those same legal speed limits. The comment about keeping up revs for proper cooling was specifically directed at people wanting to gear their 5 speeds to drop rpm's on the highway to somewhere below 2500rpm, where the fan isn't turning fast enough to cool an engine that's working fairly hard.
VW had already done the r&d and knew what worked; they geared these cars to high speed cruise above about 2500rpm, and as Stan knows, the upper limit is only limited by the engine's ability to keep itself at a reasonable temperature, which changes depending on the ambient temp. Remember, the hotter the air is going into the fan, the hotter it is coming out and the less heat it has removed! I've driven for hours at a time (in a beetle) at 4,000 and even 4500rpm, but we're talking about spring or fall days when the outside temp was 50 or maybe 60'F (or it was raining). In the heat of summer we were limited to 3500 (and at times when it was really hot out, any higher than 3200 drove oil temps sky high).
With a bigger engine that makes substantially more torque, you'll find that you can go below that lower figure a little bit (when highway cruising), for as long as the engine is loafing along at light throttle on the idle circuits it isn't creating a lot of heat. Up a long hill, engine temps will climb quickly, and the solution is to drop a gear and get the revs back up to where the engine can cool itself properly.
4.12 to 3.88 is a 6% change. 3.88 to 3.44 is between 12 and 13%, closer to 13.
It hasn't been said in this thread, but a 3.44 final with stock 1-4 is the cheapest way to get decent gearing(I would recommend at LEAST a 2 liter engine for this). Changing the mainshaft which 1 and 2 are permanent parts of isn't cheap, but like has been said, isn't that bad either.
I have made some cooling mods which I will detail in another thread, but running tall gears with a powerful motor can be done without overheating. I can loaf along around 1500-1800 or cruise between 2000-2500 without overheating. I can also run 60, 70, or 80 for hours without overheating, in 90 degree humidity. It can be done folks. But I am running only a 2165 type1 in a Spyder, so not the same as a Speedster.
Thanks for that correction, Stan. Also, my "tall" tires and wheels? 165/80-15. i.e. stock. My speedo goes to 100 and it appears to be accurate to within 1-2 mph at all speeds.
I understand that you guys drive 70+ mph for hours on end...how do you do that
Do you wear a helmet, or are you 5 ft tall? The buffeting in a spyder or speedster is pretty significant at those speeds... particularly if you are over 6 ft tall 
ReV
I understand that you guys drive 70+ mph for hours on end...how do you do that
Do you wear a helmet, or are you 5 ft tall? The buffeting in a spyder or speedster is pretty significant at those speeds... particularly if you are over 6 ft tall
ReV
Sun Screen, lots of fluids, a hat, and a few Motrin for when you get out. 
...and gloves, you gotta wear gloves.
...and gloves, you gotta wear gloves.
I totally forgot the gloves, I have big hands got a supplier
If I'm going to be doing several hours on the interstate the top is always up. Between the sun and the wind it is just too intense with the top down for that length of time.
Mr. Vosari's comment made me think of My first ride in an IM speedster I was so buffeted my head was above the windshield for only 20-30 minutes, and my hair follicles cried numbingly for hours the owner would wear a world war one aircraft head gear with glasses for any journey out of town. I went and bought a roadster after 5 years sold it and built another and even made the seats lower to get my head below the windshield. What a guy must do if he has a long torso
Yes---what Lane said. Top up for interstate travel. Quieter, cooler, less buffeting, and room for a lot of "stuff" back where the top would go anyway.
As far as high speed driving and a cool engine, I cruise on Interstates at 75-80 all day and show only 3500-3600 rpms with a 4.12 R&P and .82 final with a 25" tall tire while almost never seeing over 185 degrees oil and 225 degrees CHT. But you gotta have the 2+ liter power to use such gearing.
Yes---what Lane said. Top up for interstate travel. Quieter, cooler, less buffeting, and room for a lot of "stuff" back where the top would go anyway.
As far as high speed driving and a cool engine, I cruise on Interstates at 75-80 all day and show only 3500-3600 rpms with a 4.12 R&P and .82 final with a 25" tall tire while almost never seeing over 185 degrees oil and 225 degrees CHT. But you gotta have the 2+ liter power to use such gearing.
Hah...we have different points of view for the Interstate. To each his own. If it's not raining, I'll have the top down when running as a convertible. I enjoy the better visibility for safety reasons and with the top down, I know how much baggage you know who can stuff into the car.
But, I only travel at 60-65 mph so a big factor there. Skinny tires, drum brakes and short gears is an influence too.
When its not sunny I use a hat much like "Edge" in U2...and that's OK...but when its sunny the long beak golfer visor I use is good for the sun, but I really have to squat in the seat to prevent it from blowing away...along with sun glasses and everything else
ReV
...Which makes me post again my two favourite pics of any of our Speeedster travels.
First one just East of Grand Canyon and the second again near the Grand Canyon take by a Biker from Texas in the same area sent on to us later.
My best travelling memories are out there and I need to see Bryce Canyon in Utah sometime. And for that, caravanning would be nice.
I ALWAYS drive top down. I'm 6 ft tall, 230 when I stepped on the scale this AM (I've GOT to get back on my bike). For me, the trick is to get as low in the car as possible. I've got Fibersteel seats (which sit very low), and have them mounted as low in the car as they will go. I've also got them tipped back quite a ways, as I've got a long torso and arms and shorter legs.
My shoulder is level with the door top, and I look through the windshield, not over it (or at the top trim). I worked hard on pedal placement, welding on the stops and grinding them back so they sit perfectly in line, and leaning further forward than standard. I have no extra throttle return springs, so I suffer very little fatigue in my leg driving for hours at a time.
I've spent a ton of time and effort, and no small amount of money on anything my body touches on the car (Joel Scholtz calls them "touch points"). It's paid huge dividends in comfort. My speedster is honestly more comfortable than any other car I own.
I've got no wind buffeting, and can drive for many many hours on end (longest day so far is 1100 mi.). I cruise at 75- 90 mph, depending on the posted limit, etc.).
It's all in the set up.
I drive top down unless it is raining. Down to 32 F. But I keep layers in the car. I have a leather jacket, a hoodie, a long sleeve t-shirt, gloves, and a baseball cap. Also a wool cap, don't know the name of it, but in my mind it is a gentleman's driving cap. Mine has a fold-down earflap that also covers the back of the neck.
And I can always turn on the heat. This Carlisle trip it started at 65 and sunny, and got down to 48 and cloudy with a spritz of rain. Layers of clothes added and heat and pushed right through at 70-75.
I have cruised at 80-90 for an hour or so, and I get what some say about the hair follicles being beat up. But what's left of mine is 1/4" so a non-issue. If you have hair, wear a hat. Bald rules in these cars, though.
I'm 5'9" so my head is below the windshield(Speedster style). I can't imagine no screen or the shorter racing screens. Like Stan my shoulders are at or below the top of the door.
