what are the stock cam specs?

[workshoprat92]

Can anyone tell me where to find the stock cam specs for a buss and the stock specs for a porsche 914 engine?

thanks

[supaninja]

Here is the 914's cam spec http://webcamshafts.com/mobile/automobi ... 02437.html

[workshoprat92]

Thanks I am wondering how that differs from the 2.0 buss camshaft. I need max power at about 3200-3400 RPM range and am thinking the buss cam may be the way to go on a stock engine.

[dstar5000]

NEVER use a STOCK cam! They were designed to give NOX numbers, NOT give
performance or drivability.

See Webcam's offerings.

Don

[NathanScruggs]

Can anyone say why Web Cam's specs are so totally different than the ones given in the 914 technical specs book?
Web cam says it is this for both vw and porsche 914
Intake Open: -3 BTDC
Intake Close: 33 ABDC
Intake Lobe Center: 108
Intake Duration @.05: 210
Exhaust Open: 31 BBDC
Exhaust Close: -5 ATDC
Exhaust Lobe Center: 108
Exhaust Duration @.05: 206

This is straight out of the little book, all the FI motors including 2.0 same specs
Intake Open: 12 BTDC
Intake Close: 42 ABDC
Intake Lobe Center: 105
Intake Duration @.05: 234
Exhaust Open: 43 BBDC
Exhaust Close: 4 ATDC
Exhaust Lobe Center: 109.5
Exhaust Duration @.05: 227

At first I was thinking it was just offset but similar, or maybe that they are measuring at 0 lash vs .006, but it is just totally different it seems?

[dawie]

VW spec is at 1mm lift- (0.04 inch).

For D-Jet:

IO- 12 btdc
IC- 42abdc
EO- 43 bbdc
EC- 4 atdc

There was an unconfirmed rumour of a later slightly different 2L 914 d-jet cam. If anyone have official specs, please share.

Another near similar cam was quoted as:
IO- 9bbdc
IC- 41abdc
EO- 43bbdc
EC- 4 atdc.
This was the 1800 european 412S and 914 1800 engine. 85hp, 8.6:1, twin 36/40 pdsit/ 30mm venturies.


The basic european 411/412 engine- (68hp, 7.8:1, twin 34pdsit-26mm venturi), had:
IO- 4btdc
IC- 39 abdc
EO- 40bbdc
EC- 3atdc
This basic 411/412 engine was never sold in the USA. Think the basic 1800 412 engine (Twin 36/40 pdsit carbs/28mm venturi-75hp) probably also had this cam.
This cam was also used on the first 1700cc bus engines. (Manual transmission models only). Compression was lowered from 7.8:1 to 7.3:1 for bus use. Power dropped from 68hp to 66hp. Still same twin 34pdsit/26mm venturi carb.

For the 1700 automatic bus a different cam was introduced. This dropped power from 66hp to 62hp, now at 4200rpm's in stead of 4800 rpm's. Possible reason- more low down torque to prevent hunting between gears.
IO- 2btdc
IC- 35 abdc
EO- 35bbdc
EC- 5atdc
This cam continued on all 1800 and 2L solid lifter engines, both auto and manual versions. Possibly to limit power. (Commercial application where driver is not always the owner and do'nt care.)

Hydraulic lifter "Vanagon" /T25 shape 2L:
IO- 2btdc
IC- 33abdc
EO- 36bbdc
EC- "-3atdc" or 3btdc.

These are vw's specs as quoted in various publications. (Haynes, etc.)

If someone have more info/ corrections, please feel free to do so.

Any info on official max lift on the various stock cams?

Think the myth that "all type 4 stock cams are the same" started because of a mistake in the otherwise excellent book "How to rebuild your VW aircooled engine". This myth was spread by "internet parrots".

Note that most "rest of the world" vw buses continued using twin 34 pdsit carbs, 26mm venturies, and "72-74 individual pipe style" heat exchangers till the last aircooled t25 vehicles around 1982. Think fuel injection was used only on USA emission controlled versions.

[raygreenwood]

VW spec is at 1mm lift- (0.04 inch).

For D-Jet:

IO- 12 btdc
IC- 42abdc
EO- 43 bbdc
EC- 4 atdc

There was an unconfirmed rumour of a later slightly different 2L 914 d-jet cam. If anyone have official specs, please share.

Another near similar cam was quoted as:
IO- 9bbdc
IC- 41abdc
EO- 43bbdc
EC- 4 atdc.
This was the 1800 european 412S and 914 1800 engine. 85hp, 8.6:1, twin 36/40 pdsit/ 30mm venturies.


The basic european 411/412 engine- (68hp, 7.8:1, twin 34pdsit-26mm venturi), had:
IO- 4btdc
IC- 39 abdc
EO- 40bbdc
EC- 3atdc
This basic 411/412 engine was never sold in the USA. Think the basic 1800 412 engine (Twin 36/40 pdsit carbs/28mm venturi-75hp) probably also had this cam.
This cam was also used on the first 1700cc bus engines. (Manual transmission models only). Compression was lowered from 7.8:1 to 7.3:1 for bus use. Power dropped from 68hp to 66hp. Still same twin 34pdsit/26mm venturi carb.

For the 1700 automatic bus a different cam was introduced. This dropped power from 66hp to 62hp, now at 4200rpm's in stead of 4800 rpm's. Possible reason- more low down torque to prevent hunting between gears.
IO- 2btdc
IC- 35 abdc
EO- 35bbdc
EC- 5atdc
This cam continued on all 1800 and 2L solid lifter engines, both auto and manual versions. Possibly to limit power. (Commercial application where driver is not always the owner and do'nt care.)

Hydraulic lifter "Vanagon" /T25 shape 2L:
IO- 2btdc
IC- 33abdc
EO- 36bbdc
EC- "-3atdc" or 3btdc.

These are vw's specs as quoted in various publications. (Haynes, etc.)

If someone have more info/ corrections, please feel free to do so.

Any info on official max lift on the various stock cams?

Think the myth that "all type 4 stock cams are the same" started because of a mistake in the otherwise excellent book "How to rebuild your VW aircooled engine". This myth was spread by "internet parrots".

Note that most "rest of the world" vw buses continued using twin 34 pdsit carbs, 26mm venturies, and "72-74 individual pipe style" heat exchangers till the last aircooled t25 vehicles around 1982. Think fuel injection was used only on USA emission controlled versions.

Dawie...what you list as the basic 411/412 engine was in fact only the early 411 engine to about 1970 (carbs). After that all of the D-jet injected 411/412 used the same cam and so did all of the D-jet 1.7L 914's. All D-jet with this cam were 82hp except for California models. For a very short period of time the first injected models of 411 with 1.7L used the carbed cam. The 2.0 914 with D-jet had a different cam. I think its timing has been listed as the same as the Webcam 120. I dont have any of my notes in front of me right now.

The Webcam 72 uses the timing of the early carbed Euro cam. This was listed as the "V" series. I dont think any actually made it here with that cam except in gray market form. I think the later cam was listed as "Z" series. Used in late 411, all 412 and 1.7L 914 here.

As you note.....it was probably misquoted in that one publication from the beginning that all type 4 cams were the same....because looking at it here from US point of view....virtually everything type 4 in the beginning WAS D-jet and 90% of that was 411/412/914...and 1.7L. In the US...everything you would have found in the beginning before the first type 4 carbed bus would have had the same late "Z" series camshaft. Even most if not all of the US L-jet 1.8's used the "Z" series cam. In fact it may have been the anticipation of L-jet and tighter NOX control that sparked the creation of the later "Z" series cam.

Also most Americans in those days inspecting type 4 cams were most commonly looking at lift and duration and maybe lobe center.....which were NOT majorly different in these cams and were not the major features for D-jet vs carbed cams. The major feature difference in carbed vs D-jet cams was intake valve timing.....a requirement for D-jet.

Probably as you mention....most of the early publications were looking through D-jet shaded glasses back in the early days. From that perspective.....save for the valve timing changes and slight duration changes of the V and Z series...the early cams all looked the same. Ray

[dawie]

Thanks for your input Ray.

Outside the USA, the "basic" or standard lower powered 411/412 models continued to be sold alongside the more expensive/powerful "top of the range" LE/ LS spec cars till end of production around 74/75. That was the case in all versions- (2 door, 4 door and station wagon). It is my humble opinion that these could not have had the same cam as the 1700 L-jet or 1800S, difference in power was too big. (The 2mm difference in venturi size and compression differences alone could not account for the 10hp difference between basic 1800 and 1800S).

Maybe our German friends also have some info on camshafts/codes of standard T4 cams?

Thanks in advance.

[NathanScruggs]

Thanks for replying. I have been interested in this as I am trying to put together a totally stock 72 Bus engine. I am thinking that it would have been a 'carb cam' in the cb case, from what I have gathered.

IO- 4btdc
IC- 39 abdc
EO- 40bbdc
EC- 3atdc

I am not sure though, as by 72, it could be that all the cams were the djet late one. It almost seems like one of those 72 half year changes where all late 72 would have gone to the djet cam, despite 73 US buses being carbed, too. I am torn though, thinking it may have had the djet cam in a early 72 CB case? Regardless of this, the talk makes me want a web 73 Grind!

I have been posting in thesamba bay window forum in the "early type 4 engine thread", trying to figure this out,

http://www.thesamba.com/vw/forum/viewto ... 15dc1bd728

when it really baffled me about the difference in the web "stock" cam.

So about that, the VW cam specs are measuring with zero lash the degree at which the valve opens or closes more than 1mm or .040 inch. The Web Cam specs, they are measuring with .050 inch valve lash and taking the degree at which the valve lifts at all. This shouldn't be too different, as it is just the english and metric standard for denoting the same thing and should be comparable. Could the extra .010 make the difference? I made this gif to show it visually. The 73 looks very close. Weird that none of the web cams have any advance. I wonder what that would do to the feel. The gif though, has made me reconsider how to set my valves as there is still lift going on at tdc on intake and exhaust. But look at the difference with the Web "Stock" grind. It is totally different.

[Piledriver]

The variations in all "stock" US spec t4 cams are still essentially within the range of measurement and manufacturing error, printed specs be damned. Clock them and its damn difficult to tell which is which.(esp if you measure everything at .050)
If you can't tell, the engine damned sure can't. (possible exception is d-jet, as it's so fussy, but that can be largely tuned out)

Use a stock cam if you want your CHT ~50F higher than it has to be., while making less power and higher fuel consumption.
(vs say a Web 73 or one of Jakes variations with a bit more exhaust timing)

If you still decide to use a stock cam, note they were not made with reliability, performance or fuel economy in mind, only fast CHT rise and low emissions.

You have been warned.

If you live in California, moving may be a better option.

If you stay with the stock cam, make sure to keep the stock CR, which has an absurd effect on performance and fuel economy. (easy 10 HP between an otherwise identical 914/411 1.7 dome and Bus dished piston version)

Make sure you get a nitrided cam, whatever you do.
AFAIK only Webcam and AFAIK Jake (in-house) nitrides their cams.
Not CB
Not SCAT
Not Engle (do they even make T4 cams?)
Not anything made in Mexico, Brazil, or China.

If you don't know why nitriding cams justifies the additional cost, Google is your friend.

[NathanScruggs]

I know it is abnormal, but I am trying to build a stock motor, or put one together. Something I am doing in my 72 bus, I have some original carbs and air cleaner, and the dizzy, the heat tubes and all that. I have an unopened original motor with good comprssion. Though it is stamped EB, it has both the filler dipstick and the bus filler hole drilled - I have read these were replacements from a dealer that may not have had engine numbers but are stamped with the number of the engine they replaced. This one has the head breather tubes hammered down and sealed with silicone to make it like a 71 914 that it was in. -so EB is 73 CA only 7.3:1 1.7, probably a djet cam.

Anyway, with the valves adjusted to .006, I measured the cam to have ~.373 inches lift on the intake valve, ~.333 lift on the exhaust, so yeah, if the early stock carb cam is the same lift, the web 73's .426" for both is a big difference. I didn't check the cam timing on it yet as it has no timing scale currently - I will have to do it soon...

I may be looking at a bus motor coming up, that I could measure to compare lift. It seems the thing to do is use the EB-stamped motor as is, but if the CB had the early carb cam, I would think the 5 degrees difference in intake lobe center would make a noticeable difference in the torque, the low end power.

[Type 4 Unleashed]

Make sure you get a nitrided cam, whatever you do.
AFAIK only Webcam and AFAIK Jake (in-house) nitrides their cams.
Not CB
Not SCAT
Not Engle (do they even make T4 cams?)
Not anything made in Mexico, Brazil, or China.

If you don't know why nitriding cams justifies the additional cost, Google is your friend.

Just so every one knows, Engle will grind a Type lV blank on any of their grinds they have.

Here is one on thesamba: http://www.thesamba.com/vw/classifieds/ ... id=1401679

[raygreenwood]

Thanks for your input Ray.

Outside the USA, the "basic" or standard lower powered 411/412 models continued to be sold alongside the more expensive/powerful "top of the range" LE/ LS spec cars till end of production around 74/75. That was the case in all versions- (2 door, 4 door and station wagon). It is my humble opinion that these could not have had the same cam as the 1700 L-jet or 1800S, difference in power was too big. (The 2mm difference in venturi size and compression differences alone could not account for the 10hp difference between basic 1800 and 1800S).

Maybe our German friends also have some info on camshafts/codes of standard T4 cams?

Thanks in advance.

Actually.....the cams had little to do with the major performance changes among the basic V and Z series cams. This level of performance change was readily seen here just among US models KNOWN to have the same cam.

The primary differences in power change for the 17L were almost exclusively due to a combination of compression, the use of fuel injection and resulting fuel and ignition tuning to work with that. The sole reason for the difference in the V and Z grinds was that with the early carbed cam....the vacuum signature was not as smooth and it made it harder to tune for better HP and throttle response.
For instance the 1.7L with fuel injection in the US was generally 82hp in 411/412/914. The California version was identical in all respects except for compression and associated ignition timing to go with that. That change alone reduces HP by between 8-10 HP and quite a bit more torque loss.
The Carbs versus D-jet easily...with either cam.....reduces total power output to under 70 HP.

Both of the standard 1.7L cams...V and Z grind work just as well with carbs. They work about the same. The changes to the later cam were for optimizing D-jet because of its intake valve timing needs....needs that based around the same lobe center...the carbs do not care about.

A cam that truly is optimized for carbs would probably put out as much or more stock hp than the same engine with D-jet. Ray

[NathanScruggs]

I found this posted on thesamba and wanted to put it here, cam part numbers, from rainierdeklark out of Sweden.

http://www.thesamba.com/vw/forum/viewto ... 4&start=20

021 109 015 M --- CA engine --- pitch -3
021 109 017 M --- CA engine --- pitch -2
021 109 019 M --- CA engine --- pitch -1
021 109 021 M --- CA engine --- pitch +/-0
021 109 023 M --- CA engine --- pitch +1
021 109 025 M --- CA engine --- pitch +2
021 109 027 M --- CA engine --- pitch +3

022 109 017 A --- GE engine --- pitch +/-0 (hydro, no rings)

071 109 015...025 --- (CU?) CV engine --- (Vanagon, hydro)

021 109 021 J --- 1700 auto, 1800 engine --- pitch -2 (two rings, one left and one right)

021 109 017 L --- CE, AP, CJ, GD engine --- pitch -2 (+/-0?)

021 109 101 F --- Z engine (VW 411 1700cc) + W, EA, EB, EC, AN, GA, GB (Porsche 914) >>>> ONE single ring

I think my measurements were off previously, measuring at the valve. Besides variations in the ratio of my rockers, I think any error would have been factored by that ratio, and the harbor freight indicator I was using, I think I may have been off. I tried it again right on the valve and got figures closer to web cam's, though they kept coming up just a bit different so I don't have a good figure.

The lady I talked to at webcam offered to put a cam I would bring on their cam doctor, I think they called it. I am thinking that I want to do this with the stock 72 djet cam I've got... I didn't end up getting the CB motor I looked at to compare that one. Still looking...

[fusername]

ok this is from VW workshop manual for a T4 printed 8 '70, so its a 411-426 1700, 85 HP cam

Code: Select all

Measured @ .04
IO    -12
IC    42
EO    -43
DC    4