Advise Needed - 1966 Samba - Straight Axle or IRS?

[sambaphil]

Hi Guys,

I know there are a lot of posts about how to go to straight axle or IRS. But what would you do if you were me?

I have a 1966 21 Window that I just restored to look stock. Correct paint, correct interior, correct wheels etc.

Now that i have been driving it, I have decided that I want to go 65MPH on the freeway instead of the 50 or so (I am still running RGB's with a 2 liter engine).

I can either go straight axle which means lowering the bus by 2.5 inches or so, new front beam, 2.5 drop spindles.

Or I can stay at stock height and go with an IRS with a 68 to 70 rear end, bug irs trans. A reputable suspension expert is recommending the IRS set up but ??

What would you do if you had to choose? I don't know what route to go so any experiences and input would be appreciated.

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Link to 1966 Samba Build
http://www.thesamba.com/vw/forum/viewtopic.php?t=607420
Link to 1971 Bay Bus - Clipper - L
https://www.thesamba.com/vw/forum/viewtopic.php?t=671945&highlight=

Single Port Samba Phil
[email protected]

[mandraks]

i drove plenty bay buses, IRS does work great. 2 liter buses run great, handle good, corner good, see no reason why you should not switch to a stock height bus irs

be sure the ratios suit your expectations, bus IRS is NOT significantly faster than a big nut rgb
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regards

Uli

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'53 3-Fold Oval, L35 Metallic Blue, looking for a narrow hatch panel

[cru62]

Or regear the transmission to a Freeway Flyer. With a 2 liter you have more oomph to get to and maintain a realistic highway speed. Any reputable shop will be able to recommend the gearing you need for the type of driving you do and your engine size.

Unless you either swap bus IRS parts or go with rear discs (i.e.-Porsche or similar) you will be stuck with bug brakes and bearings. And a straight axle uses essentially the same bug parts (brakes and bearings) also unless you upgrade to bus or T-3 drums or discs.

My last bus had '73 front and rear T2 suspension and brakes. And so will my next one. Except all '68 parts to stick with Wide five bolt pattern.
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"My biggest worry is that when I die, my wife will sell all my parts for what I told her I paid for them"-Jon

Jokes about German sausage are the wurst.

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[OB Bus]

Being a stock leaning person, I'd leave your nice looking bus the way it is and enjoy the ride.
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Larry in OB
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69 Westfalia and 2002 Eurovan Camper.

[sled]

very simple.

bug IRS in the back which will lower the bus about 3.5"

flipped spindles in the front which will also lower it about 3.5"

both of which will improve the handling of the bus.

seek out a 4.12 ring/pinion transmission which will have DUAL sideplates on the trans.

what size tires do you currently have? there is a possibility you may be able to still use them (esp. the rears) with the above mentioned combo.
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drive your split.

[campingbox]

You can only drive 50mph with a 2L? Something is wrong there.....I regularly drive our '66 bus with a 1600sp at 60-65.

Bus looks great Phil!

[sambaphil]

Hi Guys,

I appreciate the input and feedback. I still need to do more research but this helps me. Busboys have a bolt on irs kit but?

Camping box, I still have reduction boxes on my bus. You say you can go a lot faster with a 1600. Do you still have Reduction boxes?

Thanks again. I will update this later after I have decided.
_________________
Link to 1966 Samba Build
http://www.thesamba.com/vw/forum/viewtopic.php?t=607420
Link to 1971 Bay Bus - Clipper - L
https://www.thesamba.com/vw/forum/viewtopic.php?t=671945&highlight=

Single Port Samba Phil
[email protected]

[OB Bus]

What size are those tires? They look small-ish in the wheel wells.
_________________
Larry in OB
Stop dead photo links! Post your photos to The Samba Gallery!
69 Westfalia and 2002 Eurovan Camper.

[Erik G]

yes, 65 should be no problem with a 1500 single port with 64-67 reduction boxes. I daily drove mine 65+ no probs, heavy 66 kombi camper.

It this your first bus? are you expecting to cruise 65 at low RPM? You cant do that. You need the high RPM to keep the fan speed up

do you know what RPM you are at at 50mph? Do you have the correct big nut trans or the earlier small nut?
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[mandraks]

[sambaphil]

It looks to me I have a big nut trans
As far as rpms, it sounds like 4,000 to me when going 50 to 55. But I don't have a tach yet. Tire size is 195/75 R14

This is my first bus as an adult, I have been doing a lot of cosmetics / engine work but when it comes to transmissions I do not have any experience. Thanks for all your input. Much appreciated.

_________________
Link to 1966 Samba Build
http://www.thesamba.com/vw/forum/viewtopic.php?t=607420
Link to 1971 Bay Bus - Clipper - L
https://www.thesamba.com/vw/forum/viewtopic.php?t=671945&highlight=

Single Port Samba Phil
[email protected]

[Clara]

[Harleyelf]

My '66 had a Bus Boys kit on it when I bought it twenty-five years ago. The rear brakes and wheel drive stubs are from a '69. The transmission side drive stubs are from a Safari (Thing) so I can use large CV joints on both sides of the axle.

To me, the key is the handling, not so much the overall gear ratio. With an IRS set-up, the rear wheels will toe out a bit under acceleration. With the original suspension, when unladen, the rear wheels toe in at a considerable angle, making the bus easy to roll. Toe out will cause wear on the inner edges of the drive wheels, but the handling improvement is immense!

I've been California-to-Florida and back three times, crossed the continental divide more times than I can count, and handled Los Angeles freeway traffic.

I use low profile tires, a dual-port 1641, and the transmission from a '71 Karmann Ghia. When I bought it, it had a '74 transmission and taller tires, but the gearing was too tall for the single-port that was in it.

[busdaddy]

Your 195/75R14 have a diameter of 25.52"
Original 7:00X14 had a diameter of 26.22"

I never liked math so you can calculate the percentage off of the top speed they cost you yourself.
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Слава Україні!

[pyrOman]

You have 2 choices that will provide the same results: IRS with stock bug gearing like I currently have, or "freeway flier" with the RGBs and slightly taller tires as I did have before doing the IRS

With the FF/RGB and tall tires combo I ran an 1835 which would cruise comfortably at 70/75, pulling the trailer even. When I did the IRS, with the same tall tires, it would do 95 at the same rpm!!! So I then install smaller tires and now it will do 70 at about 3500rpm. I do run a 2276 too.


For tire size "decisions" I use this Tire Calculator from Discount Tire. You just plug in the numbers of what you have and what you want and it gives you the difference of speeds, rpms, etc.
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Some people are so busy being clever they don't have time enough to be wise.

[sambaphil]

[sambaphil]

[sambaphil]

[quote="Clara"]

[sambaphil]

By the way, the ladies in my neighborhood love my bus.

_________________
Link to 1966 Samba Build
http://www.thesamba.com/vw/forum/viewtopic.php?t=607420
Link to 1971 Bay Bus - Clipper - L
https://www.thesamba.com/vw/forum/viewtopic.php?t=671945&highlight=

Single Port Samba Phil
[email protected]

[Eric&Barb]

Definitely you can go with a freeway flier transaxle and RGBs. Did that with our 1960 walk thru panel to get 3,000 RPM @ 60 MPH. Instead of the stock 47 MPH in fourth @ 3,000 RPM, and 3,800 RPM @ 55 MPH. Will do 70 MPH @ about 3,500 RPM, but oil temp definitely goes upward.

Buy or borrow a tach to wire in temporary, take it for a fifteen minute drive. Have a passenger hold the tach and write down what MPH you hit 1,500 RPM in 2-4th gears and 3,000 RPM in 1-4th.

As for whether or not to go with double jointed rear axles would depend on how hard you like to take the curves and turns. After all this is a bus not a Porsche! Personally prefer the easy maintenance of the swing axle and if you have the right tires, shocks and anti-sway bars it makes a huge difference.
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