Hi Folks,
I have what I think is a 1.7L D-Jet engine but with no serial number, so I figure it's a replacement case. If it has the D-Jet intake but four intake manifold studs am I correct in thinking it's a 1.7L engine? Don't know as much about the fours!

I thought the early D-jets had a circular plastic air box and I've made no measurements of the intake runners to see if this engine has been converted into a 2L using 1.7L heads. Is that possible?

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Ron

4 bolt intakes just means it doesn't have 2.0 914 heads. Based on that it could be 1.7, 1.8 or bus 2.0. If it is indeed an unnumbered case its going to be pretty hard to tell from the outside. 1.7 1.8 and bus 2.0 all had different intake setups so that might give an indication as to what it is but its no guarantee. pictures might help here but with no numbers without pulling a head and measuring it would be impossible to tell.

A couple more external things that may help improve your guess though are 1. Rocker arms (1.7 had different rocker arms than the 1.8s and 2.0s) 2. Distributor part number (provided it has one and it is assume to be original)

A real 914 1.7/1.8 serial number is on top of the case near #3 cylinder

That spot is blank as is the flat in front where the 2L serial numbers are located. We have another 1.7L engine to compare it to and it's SN is in the correct spot.

Thanks Mark

Excellent, I'll check the distributor that's on top but not installed. I didn't know about the rockers so I'll look at a known 2L and the 1.7 (both are in the shop) to see what's there.

Thanks

This is easy. The 1.7 is Slow and the 1.8 is just as Slow............

Yeah yeah!!!!

Bus engines have serial numbers right? In front of the oil tank like 2L 914's?

That is a 2.0 engine. the serial number should be located by the fan shroud behind at bottom side of the oil filler. But why is it the spark plug seems like for a 1.7/1.8 orientation. Is this a combined 1.7 djet with 2.0 trottle body and air cleaner?
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Well, from the pictures you've recently posted that air cleaner and throttle body are definitely 2.0. But you may have a mongrel on your hands, which is not necessarily unusual. Case, heads, FI, etc. may all be mismatched.

Thanks and yes, I checked there. It's a blank flat spot... looks like I'm gonna check the distributor number and take a few valve covers off to compare the rockers to other engines. In my reading elsewhere I've seen some differences in the runner ID dimensions that I'll have to start using if I can't find out with the suggestions I'm hearing now.

I don't know anything yet about the bus engines... apparently I will soon!

Thanks

True that. More diggin' is needed. Thanks.

NOT A 914 2.0

Take a closer look. Its a 914 2.0 d-jet injection system but the heads appear to be 4 bolt and have the wrong spark plug location.

This is quite odd

Given the mismatch of parts there is no way to know what you have here without pulling a head off and checking out the bore/stroke, piston style and heads.

You might be right and definitely more to dive into. I'll take a few minutes and measure as much as I can before making any concrete conclusions. Stroke is easy anyway through the spark plug hole. I have a bore scope at home... might be able to make out piston head design with that. The heads are definitely not 2L unless the bus engines had four studs on their 2L heads. But I'll take a look at the rocker arms first to see what's there and see where it leads.

Thanks!

Bus 2.0 heads are 4 bolt.

Yes it is possible, you have to cut down the end of each runner about an inch at the plenum.
I did this on my first SDS FI engine, I ran a bus 2.0 with 1.8 heads, 914 2.0 pistons and a 2.0 D-jet plenum/TB.

That's what I was going to suggest - a bore scope to see what the pistons look like, and measure the crank throw BDC to TDC (just don't use a chopstick for the measuring tool)

Good thanks. A few more queries.
Is the stroke on a bus engine the same as the 914's?

Is there any other definitive "tell" that it is a bus thing?

Were all bus engines 2Ls?

Dang. Still can't use all those chopsticks in the drawer.

To the idea that the rockers are different between the 1.7's and the 2.0Ls...

Rocker pics show that the 2L 914 engine has a coil spring between the rocker arms. Both the 1.7L and the unidentified engine have instead a spacer with two wave-washers containing the rockers. The rocker arms themselves are identical best I can tell. The rods appear different but again, I don't know about the 2.0L bus specs.

2.0L
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1.7L
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IDK.0L
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Any thoughts?

Do 2.0L bus heads use spacers and wave-washers or coil springs and

Are the bus-sparkplug holes a match for the 1.7 and 1.8L heads?

I have at least discovered that I'm looking for a stroke difference of 2mm (71mm vs 69mm)

Bus specs are the same as 914 except the 914 had bigger valves, the 2.0 3 bolt heads, higher compression pistons, and minor case differences for the application.

The 2.0 914 came first, in fact VW said the longer stroke couldn't be done, porsche designed (modified) these T4 parts. IIRC the bus didn't get the 2.0 til '75 or '76.
The crank, rods, bearings on the 2.0 bus is 039 XXX XXX which is a unique part number prefix from the 914.

Your 2nd pic is 1.7 rockers with hydraulic cam/lifter spacers, you should remove the wavy washers and replace them with the thick washer/spacers. The rocker spacers don't have to be real tight, I'd say up to .020 is acceptable. Also the adjusters don't have to be dead center of the valve end.
I use the 1.7 rockers with hydraulic cam spacers on my 2.6L type 4 engined bug.

1.7/1.8 plug holes are the same on bus/914. The 2.0 914 3 bolt head is the only unique plug hole location T4 head.

914 and bus 1.7/1.8 the stroke is 66mm, the 2.0 is 71mm stroke.

69mm is 1500/1600 type 1 beetle, - '71 bus and T3 engine.
1200/1300cc beetle etc is 64mm.

That I can work with thanks!

Ok. I'm sensing that measuring the stroke is the only thing left to do unless those spacers are a certain indicator that it's a 1.7L machine. The unknown engine has the same spacers & washers.

1.7 rockers is a clue that it may be a 1.7, but it's not proof. I can easily make 1.7 rockers work on a 2.0
Hydraulic cam/lifter spacers are off of a '78-'83.5 bus/vanagon, so they are not stock 1.7 and therefore someone added those as a mod.

I like using the 1.7L rocker arms - shave them and use 911 swivel-foot adjusters & chromoly push rods

Common mod but only worth while on a performance cam engine.
IMO required on a performance cam and a must with SS valves.

Raby 9580 cam in my 2056. Both that motor & the new 1.9L for my wife's car have SS valves.