New CMC Speedster project

I'm about to order a ton of parts from Weddle for a mountain trans for my Spyder.

I've been down to North Carolina twice, and the Spyder does pretty good going up and down the mountains. I've written most of this stuff before, but I'll keep it as succinct as possible.

I currently have stock 1-4 with a 3.44 R&P. 3.80/2.06/1.26/0.89

First and second are too short, and third is almost perfect and fourth too tall for mountain work. 4th is great for the interstate, but that's about it. 3k is 70, 3500 is 80.

I'm going either 3.44/1.93/1.30/1.0 OR 3.11/1.93/1.35/1.04, both with the 3.44 final.

3.44 first is only a little taller than stock, 3.11 a little taller than that, but not quite halfway to the factory 2nd.

The first combo is very slightly wider-spaced than the second, which would probably make me happier most of the time. The second combo would be perfect for mountain use only.

I'll compare this to my modern Cayman trans. It's like a 6 speed without first or sixth. Honestly nobody really NEEDS sixth gear, and as Ed says, the VW first gear is for getting 4 people up a mountain with 40 hp. I have 180hp in my Spyder.

On the racetrack, at speed in the Cayman at Watkins Glen, I only used 3-4. I did touch redline in 4th for a couple seconds before the braking zone. It wasn't worth shifting up to 5th.

The 3.44 final is great because I have 195/60 rear tires which are 24.2" diameter.

You get almost the same exact gearing with a 3.88 with a 25.4" tire(185/70 or 165/80).

It does make a difference in gearing what tires you run on your car. Just keep that in mind.

Go to Weddle.com, and see what they have available. Then use their calculator to fine tune. Pay attention to shift points, rpm drops, speed range of each gear, speeds in gears(big spreadsheet chart) and very important: percentage of pull. This last one will give you a good idea of how the trans will feel when driving. Getting as even as possible here pays dividends in drivability.

Also pay attention to what speeds your torque peak occurs in each gear. This is where you want to be at say 30, 45, 55-60. You know, the speeds you spend a lot of time at tooling through town.

I don’t know if it helps, or matters, but this is what I arrived at when I was pursuing my “Carrera” gearing.

Weddle 3.11/1.86

3.11/1.86 1/2 Main shaftWB-311186

3.11 1st gear idler WA-311I

1.86 2nd gear idler WA-186I

3&4 I was going to leave the same. 3 is perfect for grades, 4 is perfect for cruising  

1-6 in Six speed is exactly right. I only use 1st in my 968 when I come to a complete stop, and 6th only when I’m droning down the freeway with the cruise control on. It only drops the rpm about 150 from 5th.

3.11/1.86 is NLA. You can get 3.44/1.93(backorder) or 3.11/1.93(in stock) at the moment. Not a whole lot of difference between 1.86 and 1.93 really.

I'd change 3 and 4 if only slightly. Your 2-3 drop is gonna suck if you change 1-2 using a stock 3rd.

@dlearl476 posted:

I posted what Greg used in his transmissions somewhere before. I’ll see if I can find it. FWIW, I think he had these made for him by Rancho. Kind of a custom Freeway Flyer.

Here it is. From Greg:

3:88 R&P

310. 1st

193. 2nd

121. 3rd

082. 4th

I got these numbers from him when I was contemplating recreating, as closely as I could, the “BBAB” gear ratio set that came with the original 550’s and 356 Carreras. I have a feeling they go with the optional 2335 motor Greg uses. I don’t know if he’d recommend it for the smaller, standard engine, for all the reasons Ed mentioned.

This gearset does work well with a bigger engine, although the 1-2 split is a little short and 2-3 is a wee bit long (1.86 for 2nd would be better but they don't make the 3.10- 1.86 mainshaft any more).  Stock recovery points when upshifting at 3500 rpm are 2nd- 1900, 3rd- 2200 and 4th- almost 2500 rpm. Shifting out of 1st with this custom gearset at 3500 rpm nets just under 2200 in 2nd and almost exactly the same rpm into 3'rd- ideally you want the rpm drop to be 100 or so less into 2nd and the recovery point to go up with each shift.  The 3rd into 4th gear shift lands at just under 2400- a wee bit low by stock standards, but with anything bigger than a 1600 (and with the Speedster's low frontal area and reasonable aerodynamics) it will work, as long as you take care not to lug the thing up hills.

@DannyP posted:

3.11/1.86 is NLA. You can get 3.44/1.93(backorder) or 3.11/1.93(in stock) at the moment. Not a whole lot of difference between 1.86 and 1.93 really.

I'd change 3 and 4 if only slightly. Your 2-3 drop is gonna suck if you change 1-2 using a stock 3rd.

I actually abandoned the whole idea. When I added it all up, including a Rhino case and all the bits and pieces, it was almost an $8K transmission. If I ever get a new one, I’m just going to source one of Greg’s optional boxes in the ratios I previously posted.  

FWIW, The gap in a stock box is 206-126= 80.  The 2-3 gap in Greg’s box is 193-121=72.  The gap from the Weddle 2nd->Stock 3rd is 186-126=60. The Carrera box is 176-123=53

Is my math off? It seems to me the Weddle 186 2nd closes the gap to the stock 126 3rd substantially.

eta: If the Weddle 311-186 is NLA, the difference between a 193-126 and Greg’s 193-121 box isn’t that much either. Certainly not enough to justify the ~$3K that the Weddle layshaft and idlers were IIRC.

A custom 1-2 mainshaft is $479. With the idler gears added ($219 each) plus the special 3-4 slider, it's about $1000. Custom 3rd and 4th is about $400 each.

All custom gears adds $1800 to the transmission, not $3000. These cars are sometimes expensive, sometimes not. It all depends on how bad do you want X modification? How far are you willing to go($$$) to get what you're after?

A Rhino case is somewhere in the vicinity of $500. Add in a differential(300?), ring and pinion(500-1300), side covers, synchros, and bearings, it does add up. I don't find it necessary to install a Torsen TBD in such a light car, especially for road use. Track/autocross is different though, if that was my primary usage, I'd get the Quaife(1300-1600).

$8k? That's about 3k too steep, assembled by a trans guy.

Me, I'm putting it together myself. Yes, you need the special pinion nut tool. Yes, you need a hydraulic shop press. Today, most trans guys use gear marking compound to set the ring and pinion instead of the VW unobtanium toolset.

I was told that I "couldn't" rebuild my trans myself and get it working in the car. Whatever, those guys have shut up now.

I've got the rack and pinion steering on the way, and I'll be building a nicely spaced mountain gearbox. I'm trying to make my Spyder the best it can be for my intended usage. It's really good right now. I'm going to make it better.

@ALB posted:

This gearset does work well with a bigger engine, although the 1-2 split is a little short and 2-3 is a wee bit long (1.86 for 2nd would be better but they don't make the 3.10- 1.86 mainshaft any more).  Stock recovery points when upshifting at 3500 rpm are 2nd- 1900, 3rd- 2200 and 4th- almost 2500 rpm. Shifting out of 1st with this custom gearset at 3500 rpm nets just under 2200 in 2nd and almost exactly the same rpm into 3'rd- ideally you want the rpm drop to be 100 or so less into 2nd and the recovery point to go up with each shift.  The 3rd into 4th gear shift lands at just under 2400- a wee bit low by stock standards, but with anything bigger than a 1600 (and with the Speedster's low frontal area and reasonable aerodynamics) it will work, as long as you take care not to lug the thing up hills.

@ALB My selections are pretty good: recovery drops from 6000(sometimes 6500)rpm shiftpoint:

2634 drop into 2nd(3366rpm)

1959 into 3rd(4041rpm)

1385 into 4th(4615rpm)

All of these are SMACK DAB into the meat of the torque curve of my engine. 3500 up to 6000 is basically flat as a table. Really it starts at 3000.

@DannyP posted:

I was told that I "couldn't" rebuild my trans myself and get it working in the car. Whatever, those guys have shut up now.

This all stemmed from me (once upon a time) saying that I would let my friend Bruce take care of my transaxle needs, so Danny is referring to (mostly) me.  If he were to take the time to remember correctly the conversation when he embarked on this endeavor I said that to buy the the press (if you didn't have it already) and transaxle specific tooling was expensive and learning curve steep if you were to ever only build 1 or 2 transaxles.  Many guys end up pulling their first trans rebuild back out a couple or even 3 times before getting it work properly, and if all you're ever going to do is 1 or 2 (or maybe even 3) that part really didn't appeal to me!   Everyone here knows Danny is an intelligent guy with good mechanical skills and no one said he wouldn't be able to do it.

I never had any doubt he would be successful, so

                           Danny, settle down you POOPIEHEAD!

@DannyP posted:

A custom 1-2 mainshaft is $479. With the idler gears added ($219 each) plus the special 3-4 slider, it's about $1000. Custom 3rd and 4th is about $400 each.

All custom gears adds $1800 to the transmission, not $3000. These cars are sometimes expensive, sometimes not. It all depends on how bad do you want X modification? How far are you willing to go($$$) to get what you're after?

A Rhino case is somewhere in the vicinity of $500. Add in a differential(300?), ring and pinion(500-1300), side covers, synchros, and bearings, it does add up. I don't find it necessary to install a Torsen TBD in such a light car, especially for road use. Track/autocross is different though, if that was my primary usage, I'd get the Quaife(1300-1600).

$8k? That's about 3k too steep, assembled by a trans guy.

Me, I'm putting it together myself. Yes, you need the special pinion nut tool. Yes, you need a hydraulic shop press. Today, most trans guys use gear marking compound to set the ring and pinion instead of the VW unobtanium toolset.

I was told that I "couldn't" rebuild my trans myself and get it working in the car. Whatever, those guys have shut up now.

I've got the rack and pinion steering on the way, and I'll be building a nicely spaced mountain gearbox. I'm trying to make my Spyder the best it can be for my intended usage. It's really good right now. I'm going to make it better.

Like a lot of things, it seemed like it was bigger in the past.

Still, when compared with $1100-$1200 for a standard FF, it’s a hefty investment.

@ALB posted:

This all stemmed from me (once upon a time) saying that I would let my friend Bruce take care of my transaxle needs, so Danny is referring to (mostly) me.  If he were to take the time to remember correctly the conversation when he embarked on this endeavor I said that to buy the the press (if you didn't have it already) and transaxle specific tooling was expensive and learning curve steep if you were to ever only build 1 or 2 transaxles.  Many guys end up pulling their first trans rebuild back out a couple or even 3 times before getting it work properly, and if all you're ever going to do is 1 or 2 (or maybe even 3) that part really didn't appeal to me!   Everyone here knows Danny is an intelligent guy with good mechanical skills and no one said he wouldn't be able to do it.

I never had any doubt he would be successful, so

                           Danny, settle down you POOPIEHEAD!

Actually, it was a couple of cats who reside in the gestapo state of Maryland. One rocket scientist, in particular, also was 100% sure my car would a) not be finished by Carlisle 2017, and b) not be driving if it was there.

He was wrong on all counts.

And Al, I do remember the conversation.

Now YOU settle DOWN!

@DannyP posted:

Actually, it was a couple of cats who reside in the gestapo state of Maryland. One rocket scientist, in particular, also was 100% sure my car would a) not be finished by Carlisle 2017, and b) not be driving if it was there.

He was wrong on all counts.

And Al, I do remember the conversation.

Now YOU settle DOWN!

Danny,

Take it easy on Al. He can't help it. They don't have caffeine in their Mt. Dew; which explains a lot of things now.

Yeah…..   I could never do any long-haul driving across Canada without my trusty and highly caffeinated Mt. Dew.  At least their coffee’s better.

@DannyP posted:

Actually, it was a couple of cats who reside in the gestapo state of Maryland. One rocket scientist, in particular, also was 100% sure my car would a) not be finished by Carlisle 2017, and b) not be driving if it was there.

He was wrong on all counts.

And Al, I do remember the conversation.

Now YOU settle DOWN!

You mean I didn't cause this latest little sh*t storm?  Well Halleluja!

@Robert M posted:

Danny,

Take it easy on Al. He can't help it. They don't have caffeine in their Mt. Dew; which explains a lot of things now.

See?!  Robert knows- it's not my fault!  _{(well, there actually is a little, but not nearly as much as yours, which is soooo much better!  Talk about being bright eyed and bushy tailed after a simple soda...)}