by Brian Verbeek
I saw a CT engine (used in May'79 to Dec'82 Transporters, 1584cc, 50HP (37Kw)). It's based on the T1/T3 case. It has factory HYDRAULIC LIFTERS and an OIL FILTER MOUNT cast into the left case half, next to the oil pump, above the rear pressure relief valve (only one), parallel to Cyl #4, slightly angled downward. I bought it for 75 Guilders, a shortblock with cylinders, fanshroud and oil cooler.
The fanshroud looks like a T4 unit but is made of pressed steel instead of magnesium. It has a O-ringed dipstick hole and the T3 oil filler opening. No boss or stud to mount a regular thermostat: on this engine it's bolted to the oil filler opening studs. The crank mounted fan hub can be replaced by a regular crankshaft probably (if one were considering converting it to upright).
On the other side of the crank it has four dowels and a gland nut, identical to the upright engines. The opening for distributor, fuel pump and generator stand are all there. Only the generator stand studs are 6mm instead of 8mm as we're used to. They only have to hold a plastic, O-ringed breather tower, similar to the T3 engine.
The lifters slide in from the pushrod side, they are about 2.5" long and have an oil groove of approximately 3/4" wide. Cam lobes are narrower than the regular upright cam. The oil pump is identical to the 70s 1600s. The three holes for the rear engine mount are there, but the mount itself is different of course. The case has some additional mount bosses and webbing cast on the rear, looks a bit T4.
It has the usual sump screen as well, no drain plug in the plate. If you look into the cylinder openings of a regular upright you'll see the main bearing case webbing. These have hollow spots in them. The CT case has these filled in. It's NOT deep studded, but it does have 8mm headstuds with casesavers.
It has T4 like hydraulic lifters which slip in from the head sides of the case, has normal DP upright 4 rivet cam gear and oil pump, and has longer thread sparkplugs, filter, and is made out of AS21 or AS41. It has a single carb, stock 69mm crank, probably with the 215mm flywheel (which i also had in my '78 1600 single cab). The flywheel attaches with regular glandnut, not with the 5 bolts like wasserboxers have.
It has the three rear engine mount bosses drilled and tapped. If considering converting to upright, there are no bosses cast into the case to mount the pulley tin, not enough meat to drill and tap. Also, on the rear of the case you'll find four cast on mounting ears for the fanshroud (these need to be removed should one wish to convert to upright). The oil cooler in and outlets are in the "L" case half between the distributor and where the upright shroud would be. A solution to this might be to use a doghouse cooler and adapter in a slightly modified non doghouse shroud.
A German machine shop (BAS) didn't like the engines too much, they have seen too many problems with them, though I think it would be the ultimate case (if there were plenty around which there are not). BAS said the cases were not as good as the regular T1/T3 cases. The machinist thought that was proved by the fact that VW discontinued it after only a few years of production. I personally think that that could be due to other reasons as well. It might not be a popular choice for Transporter/Vanagon buyers. Not to forget, VW came with it in '79, there was a little oil crisis then if I'm right... It didn't last very long and people were looking for more performance again. I can imagine that a 1600 Transporter/Vanagon would be rather underpowered.
BAS says the filtercase is of poor quality. According to them it has 8mm oilgalleys (with hydraulic lifters ?!), only one oilpressure relief valve and suffered sealing problems at the case parting line. Those would be the main reasons why VW discontinued it after a short period of production ('79-'82).
It would still be nice to convert one to upright though. It has a T3 like oil filler and long dipstick in the same location as T1/T2 uprights, fan mounts on a hub on the rear of the crank, engine still has no rear oil seal (wasserboxer does). It uses heater boxes which are longer (only the rear ends are extended). If you'd shorten them they would fit a standard muffler. Original heaterboxes to these motors are often found cheaply at VW events here in Holland. The oilcooler is mounted in T3 fashion and also has the oil pressure switch mounted on it.
The filter boss is cast on at the rear oil pressure relief area, at the rearmost of the left case half. It points to 8 o'clock. It has the same bore and stroke as the upright engines, the crank, rods, P&Cs, valve covers, oil pump, fuel pump & distributor location are identical. It has a hydraulic cam and lifters which slide in after the case is bolted together. I didn't get the pushrod tubes with it but I think they are the same as Wasserboxer tubes. They are thicker on the case end.
The cooler is mounted the same way as in T3s, but then on top of a 2.5" thick spacer. But (and this is one of the main problems should one wish to conver to upright), its mounting holes are behind the usual location. If you look at the top of a T1 case, between the bellhousing and the distributor, you see it's divided by the case webbing (on which the upright fanshroud sits) into three almost equally sized partitions. Now, we are used to having the oil cooler holes in the middle part, but this one has them moved one part to the rear, towards the distributor. This could be solved by using a dog house cooler and adaptor in a non DH fanshroud and cutting the shroud were it has to fit over the cooler adaptor. Adjustments to the cooler location can easily be made by flattening the adaptor or by using pieces of the spacer which comes with the Vanagon 1600.
Under the cylinders there are T3 cool tins (in fact, they can still be called T3 cool tins) but they are clamped onto 8mm headstuds. The older T3 ones used to mount on 10mm studs so the mounting tabs are different (their part number starts with either 070 or 171).
The other main problem (if converting to upright) is that the case has four cast on mounting ears for the rear mounted fanshroud. These have to be removed by either machining and a little remodeling or with a saw and lot of remodeling. That can be done, but there is not enough meat to drill and tap for the two M6 bolts that are supposed to hold the pulley tin.
The oil cooler holes in the case aren't cut for regular cooler seals. (To convert to upright) I figure that you -could- use a doghouse shroud if you'd use a DH adaptor along with the 2.5" spacer. The spacer would go right through the fanshroud. But there's another problem with the cooler adaptor too. You have to use dual carbs as the cooler adaptor sits in the way of the stock manifold.
Stock Aluminum T1 cases?
As for aluminum T1 cases, I've heard of a limited number of aluminum cases. They would have been made in Emden or were installed in cars that came from the Emden factory, I don't recall who told/wrote me--it's all I know. I have never seen one and don't know if this rumour is really true.