3.44:1 r&p

I now have in stock brand new 3.44 ring & pinion sets priced @ $ 690 ea . These units are factory vw from brazil and are perfect for high HP applications or freeway driving .They use a late splined 4th gear and have a snap ring retainer . I also have in stock new 3.88 ratios priced @ $ 210 ea , thanks ROD , 02-42729920.

Oh that sounds like a great idea

Rod, what would the ratios be like using the 3.44 in a single side plate late (1971) type 3 g/box.
Will it stand up to 160hp OK

This is for my Flat 6 powered T34 KG.

With my current G/box 100kph in top = 3100rpm. I want to drop this down to 2500rpm @ 100kph
Also want a higher 1st Gear, And to hit 100mph (160kph) at 6400rpm in 3rd gear. Can do it now but need to up the rev limiter to 7000rpm. (too high for a T spec flat six)

U2U your email address, ratios and tyre size and I can graph them for you

like this

Astro , I think the ratios will be standard Type 3
1st = 3.80 to 1
2nd = 2.06 to 1
3rd = 1.32 to 1
4th = 0.89 to 1

Using the 3.44 final drive above

Tyres are 15" 205/55

Hi Dean


Im not sure what ratio your box has, but Type 3 boxes have 4.125 final drives
I just did ratios you said in the Berg program.


The Gear Ratio's And Tire Size For This Chart Are
1st 2nd 3rd 4th R/P Tire Size
3.80
2.06 1.32 0.890 3.440 24.01
MPH PER EACH GEAR
RPM 1st gear 2nd gear 3rd gear 4th gear
3000 16.40 30.25 47.21 70.02
3200 17.49 32.27 50.36 74.69
3400 18.59 34.29 53.51 79.36
3600 19.68 36.30 56.65 84.02
3800 20.77 38.32 59.80 88.69
4000 21.87 40.34 62.95 93.36
4200 22.96 42.35 66.10 98.03
4400 24.05 44.37 69.24 102.70
4600 25.15 46.39 72.39 107.36
4800 26.24 48.40 75.54 112.03
5000 27.33 50.42 78.68 116.70
5200 28.43 52.44 81.83 121.37
5400 29.52 54.45 84.98 126.04
5600 30.61 56.47 88.13 130.71
5800 31.71 58.49 91.27 135.37
6000 32.80 60.50 94.42 140.04

Now with a 3.88


The Gear Ratio's And Tire Size For This Chart Are
1st 2nd 3rd 4th R/P Tire Size
3.80
2.06 1.32 0.890 3.880 24.01
MPH PER EACH GEAR
RPM 1st gear 2nd gear 3rd gear 4th gear
3000 14.54 26.82 41.86 62.08
3200 15.51 28.61 44.65 66.22
3400 16.48 30.40 47.44 70.36
3600 17.45 32.19 50.23 74.50
3800 18.42 33.97 53.02 78.63
4000 19.39 35.76 55.81 82.77
4200 20.36 37.55 58.60 86.91
4400 21.33 39.34 61.39 91.05
4600 22.29 41.13 64.18 95.19
4800 23.26 42.91 66.97 99.33
5000 24.23 44.70 69.76 103.47
5200 25.20 46.49 72.55 107.61
5400 26.17 48.28 75.34 111.74
5600 27.14 50.07 78.13 115.88
5800 28.11 51.85 80.92 120.02
6000 29.08 53.64 83.71 124.16

3000rpm = 70mph (112km/h) = 60mph @ 2570rpm. Nice!

BUT the 205/60/15 tyre on my car measures 23.3 inches, not 24 so you might need to take that into account

Hi

I took the tyre measurment from my Falkon catalogue, it said that they were 610 mm, 610 / 25.4
= 24.01 inch

The 3.44 looks like the way to go.

Steve

[ Edited on 3-9-2006 by 1303Steve ]

Maybe they are measured with no load - put the weight of the car on it and there's some squash. Maybe we should all measure the distance from ground to centre of wheel to get radius, rather than diameter...?

But yeah, 3.4 looks like a good addition to my next box

its the circumference of your tyre that counts. measure how far the car rolls in one revolution

Grey,

Thanks for the Steve. I think my current box must have a 3.88 R & P as I am doing about 3k at 100pka. So its likely that its a Super Beetle box. Its not actually a single side plate but a twin.

I have a replacement Type 3 box that I wanted to build up into a high ratio unit.

Steve, is the top ratio calcs for a 3.80 or a 3.44 R&P??

Ha scratch that question Steve read it properly now.

But it looks like the 3.44 might be the go.

Thanks for the graph too Astro. Cheers

[ Edited on 3-9-2006 by Grey 57 ]

Couldn't be certain mate. It may be the same ratios, but with a 3.66 R&P (not sure though).

If you want graphs on other combos just let me know what the details are.