Is it correct that a standard gearbox will give a road speed of 50 mph @ 3,000 rpm, and a high-ratio box 60/70 mph for the same number of revs?
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Is it correct that a standard gearbox will give a road speed of 50 mph @ 3,000 rpm, and a high-ratio box 60/70 mph for the same number of revs?
Speeds refer to top gear incidentally.
Tires are 95/60 on 15-in wheels
Being as how the subject was brought up
There's more to it than that; tire size figures into the equation to. My car with overall fifth gear ratio of about 3.5 to one does a 70 mph cruise @ 3,250 RPM with 195/65x15" tires.
(Message Edited 12/17/2002 5:07:40 PM)
(Message Edited 12/17/2002 5:07:40 PM)
Bill.
You are way ahead of me on figuring your ratio. I can offer that using 185/65s, and a 3:88 with a taller 4th, a very comfortable 3500 RPM (on my engine)puts me right in the flow at 70 or 75. In the summer with 100'+ temps (road temps 120-130) I can cruise easily 70-75 as long as I've got gas... using an external oil cooler/fan/thermostat. Plus it handles longer bursts at 4000-4500 when you want a kick in passing slower lanes. Don't know if this helps... but. Oh, I figure weight has to be a factor in the heat/rpm/cruising equation.... I have a VS with the following weight add ons: Oil Cooling system, full VW spare with jack and tool bag, ER Bag of partsm etc, Modified 1776 and merged system, amp and CD changer, luggage rack, and my 190 lb body.
Jim
(Message Edited 12/17/2002 6:02:21 PM)
You are way ahead of me on figuring your ratio. I can offer that using 185/65s, and a 3:88 with a taller 4th, a very comfortable 3500 RPM (on my engine)puts me right in the flow at 70 or 75. In the summer with 100'+ temps (road temps 120-130) I can cruise easily 70-75 as long as I've got gas... using an external oil cooler/fan/thermostat. Plus it handles longer bursts at 4000-4500 when you want a kick in passing slower lanes. Don't know if this helps... but. Oh, I figure weight has to be a factor in the heat/rpm/cruising equation.... I have a VS with the following weight add ons: Oil Cooling system, full VW spare with jack and tool bag, ER Bag of partsm etc, Modified 1776 and merged system, amp and CD changer, luggage rack, and my 190 lb body.
Jim
(Message Edited 12/17/2002 6:02:21 PM)
Jim
Sounds like you're in the RPM range where I'd like to be. Do you know if these "freeway flyer" transmissions have the trans gears changed to up the cruising speed? This is an area where I'm almost totally ignorant (no drum rolls or comments please). Don't know nothin 'bout dem VW transmissions...guess I outta buy a book - if I knew which one.
OH WELL
Sounds like you're in the RPM range where I'd like to be. Do you know if these "freeway flyer" transmissions have the trans gears changed to up the cruising speed? This is an area where I'm almost totally ignorant (no drum rolls or comments please). Don't know nothin 'bout dem VW transmissions...guess I outta buy a book - if I knew which one.
OH WELL
Bill, there are several VW transaxle specailty shops that can build you a transaxle (Rancho is one) and they all advertise in "VW Trends" and "Hot VW's' magazines. Just call them and tell them what your engine set up is (BHP/torque), how much your car weighs, and how you drive your car and they can build it for you with all of the right ratios (and a "super diff", if necessary).
Thanks George!
Ditto for "Der Transaxle" out of Anaheim, CA.
Bill,
I ordered mine from Der Transaxle while it (The VS) was being put together. Just tell them that you want to be able to hold your RPMs to the 32-3600 range for highway cruising, andddd that you still like 1st and 2d stoplight ratios... They did me right. Now, if I had that same foresight on the engine I would have saved boo-coo bucks.
Jim
I ordered mine from Der Transaxle while it (The VS) was being put together. Just tell them that you want to be able to hold your RPMs to the 32-3600 range for highway cruising, andddd that you still like 1st and 2d stoplight ratios... They did me right. Now, if I had that same foresight on the engine I would have saved boo-coo bucks.
Jim
Der Trans Axle Shop, 2910 East Miraloma Avenue, Anaheim, CA 92806. Phone: (714) 630-7292