Type II IRS Conversion
Getting Some Speed out of Your Old Transporter
By VWT Staff
Most people have a lot of respect for a Transporters that are still on the job after all these years. Though they can be used to haul most anything from point A to point B (including up to a half-dozen of your closest friends), one of the largest complaints from the most people is the lack of speed. Even with engine upgrades like larger displacement and intake/exhaust mods, most stock Buses lack the power to keep up with the breakneck pace of Southern California traffic. Such is the case with our project Single Cab.
This was largely due to the reduction boxes on the end of the axles. They consist of two gears encased in a metal housing that effectively reduce the gear ratios from the transmission. Volkswagen wanted the Single Cab to be able to haul heavy loads, so instead of just lowering the ring and pinion ratio, they added four extra gears and two extra bearings to the trans. This are fine if you want to haul a 3/4-ton payload or go 65mph down the freeway with the gas pedal to the floor. But, that's not fine with us.
We checked into the idea of a 3:88 ring and pinion, like we have seen on several period Type IIs, but that would still force us to the use the reduction boxes. Since we never planned to restore the Single Cab back to factory specifications, the reduction boxes didn't really need to be there. Next, we checked out the swingaxle conversion, but using that method of deleting the reduction boxes means that you have to lower the rear of the Type II by about three inches, a look (and function) we didn't care for. We wanted to keep the height stock.
Old Speed, in Paramount, Calif., has come up with a way to accomplish what we wanted: Install an independent rear suspension (IRS ) transaxle, complete with trailing arms, C.V. joints, axles and brakes, from a 1969 and later Beetle, into the Type II. This way, you can retain the stock ride height, and the transaxle's gearing is like its Sedan counterpart, On top of it all, we would be able to keep up with the flow of traffic. If you're looking to alter the ride height in the future, the beauty of an IRS conversion is that you can sit anywhere between "in the air" and "in the weeds" and not have the tires tuck in at the top like with the swingaxle conversion.
Old Speed offers this conversion either as a kit or a "drive it in, drive it out" service. With the latter, Old Speed provides all the necessary components, such as a rebuilt IRS transaxle, (whatever performance level you require), all new brake drums, wheel cylinders and brake shoes, and all the other associated hardware.
Another nice thing about the Old Speed IRS kit is that nothing is taken away from the original setup. All the brake line tabs, mounts and hardware are still there, and the only modification, if it could be even called that, is that the original brake and parking brake lines have to be bent a little to work around the trailing arm brackets.
Since the Single Cab's main function is as a parts hauler we elected to upgrade the transaxle. Enter Kevin Richards, proprietor of KCR VW Transmissions, in Riverside, Calif. Kevin is well-versed in VW transaxles, as his dad used to work for EMPI back in "the old days," and Kevin has been around VWs for as long as he can remember. His transmissions are in some of the fastest VWs in the U.S., and one of the transaxles of choice for quite a few of the Der Renn-Kafer Cup Series cars.
When speaking to your transaxle builder be honest with your intentions. They cannot help you if you buy a stock rebuild and attempt to heal-tow the clutch at 6000 rpm all the time, and bring him back a transaxle full of metallic Jello. Kevin suggested that we go with the IRS Type 1 transaxle with a Klinkenberg 4:12 ring and pinion and a 3.80 first gear, a 2.06 second, a 1.26 third and a 0.089 fouth. In addition, he recommended that we have third and fourth gears welded, steel shift forks, hardened keyways, IRS Super-Diff. and a heavy-duty aluminum side cover. Kevin calls this his "Super Street" transaxle, and it's a terrific value.
The Source
OLD SPEED 7311 Madison Street, Unit "A" Paramount, CA, 90723 (562) 531-4190 www.oldspeed.com
KCR VW TRANSMISSIONS 9000 Arlington Avenue, #108 Riverside, CA 92503 (909) 688-1904
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This is an IRS transaxle from Kevin Richards at KCR Transmissions, in Riverside. Although Old Speed does the installation with a rebuilt stock unit, and 99 percent of the time that's fine for most applications, we wanted to make sure the Single Cab was still fully functional as a work truck to haul things and tow future project cars. This transaxle will more than fill the bill.
The first thing Old Speed does is to lift the truck up on one of their lifts and remove the engine. This is necessary to expose the core work area: the transaxle. Though this is not a job for the beginning VW enthusiast, it is something that can be done with the basic of shop tools.
Remove the brake drums and parking brake cables, trailing arm bolts, cradle mount bolts the nose cone mount nuts, clutch cable, starter, and drain the oil out of the center section and both reduction boxes.
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