67 Alt. Pulley 3844100

[plumL78]

 I think Phil has over 200 67 L78s in his reg.  We haven't found one that can prove they came with the 1100 AK pulley.  The camaro guys that have been doing these cars for years say they came with the 387 AI pulley. Out of all the reg. cars there are only a couple orig owners and they don't have that 1100  pulley. Most likley they came with both pulleys and may have been a time issue. If you came to the camaro nats.  to be judged with the 387 AI pulley on a 67 L78 they would say its correct. We are going to see two orig L78s in the near future that are very orig. and will post the results of what we find

[plumL78]

The green L78 that Dave Minor had in his collection would be a great car to look at. I believe it is all orig with no miles. Never seen it in person but it was at the Fred Gibb show a few years back and I got some pics from it. Not close enough to see #s but the pulley looked like a 387 Pulley. Does any body know if the family sold his cars after he died or do they still have them .

[big iron]

I find it strange that the 67 AIM L78 A4 shows that the 3844100 pulley was installed from the start and the 69 P&A also shows the 3844100 w/ 3.218 dia. pulley as a service replacement.
The 69 P&A also shows the 3829357 w/ 3.625 dia.pulley as a service replacement for the 67 302.
I would think the smaller pulley would be needed for the lower RPM limit of the 396.
Could the AK code have something to do with the 42amp. K79 and 61amp. K76 alternators that was available in 67.
Bob

[acelr8]

If you use the 387 pulley the belt does'nt fit. They will also say the 67 L 78 had the Z 3.25 BC fan on it too.Jeff

[big iron]

Jeff,
Sorry for the 3829357 typo. Good point about the belt (3849739) fit as the Z pulley is  .400 + - larger.
Please explain Z 3.25 BC  fan on it to. I thought that the 3843346 fan was used on both.
Bob

[acelr8]

Contrary to what some say the 67 L 78 had a 3 inch BC clutch fan with 5 rivets in an x pattern. pic available.There is a diff in the clutch BB vs SB in shaft length.The 68 belt is longer to fit the 387 pulley.Jeff

[plumL78]

I said I would post the results from A couple survivor cars that I knew of. The first car is an orig owner 07B car  so it a very late car. It has the 44100 pulley and the five rivet fan. It also has the later style alt fan. The other car is a very early 04B car that I have seen before and I'm sure it has a 387 pulley and I know for sure it has the four rivet fan. The owner isn't near the car but will be in a week or so and is going to let me know. He thinks it has a 387 pulley too. I have some  pics. of it some where but I can't seem to find them. Both these cars are very orig.  There is one other L78 that is a low milage survivor we are trying to get some information from . Thanks Kerry

[Steve Shauger]

I owned a 19k mile survivor 67 L78 that was built 7B and it had a 3844100AK pulley on the original alternator. I tend to believe the early cars received the 387 and the later(at least a few) received the 100's. Hope this helps.....

[big iron]

plum78,
Please explain later style fan. I thought the black 3843346 alt. fan was used on all 67 Z's and L78'S.

The 67 AIM L78 A4 was drawn in 12-22-66 and released in 2- 17- 67. It could have covered later production but there are no revisions unless there was one some time toward the end of production and does not show in the present AIM.
Bob

[plumL78]

Bob This is the alt fan I talking about. This pic. is from an orig owner 67 L78. This guy was there the day it came off the carrier. You can see the 3844100 on the pulley. Out of all the cars in the registry he is one of two orig owners  that we know of.   The other car was a race car and was for sale last year so I don't know if it got sold. It was far from any kind of orig. car.

[rare4k]

My theory about this is, The Early L78 cars 03-04-05 build date cars used the 387 pulley and the Z/28 fan.The 06-07 cars used the 4100 pulley and the small fan five rivet. From Doing the research lets go back and recall the 03-04-05 build date cars also had the 391 heads I believe the change was done at the head change in 06 when the started the use of the 840s. Also the Production cars that used the 4100 pulley the part No# was on the pulley the ones on ebay listed as nos are incorrect they have no part no# on them

[Steve68]

As Bob pointed out, the AIM shows a drawing date of 12-23-66 and part number 3844100 for the L78.  The October 67 P&A does not show any part numbers specifically for the 396 or the Hi Performance L78.  The October 68 P&A does show 67-68 Camaro (302) as 3829387 and 67-68 Camaro (396) as 3844100.  The October 1970 P&A shows the same diameters as the 68 P&A but lists the applicable year as 67 only.  Outside diameter for the 387 is given as 3 5/8 (3.625) and the 100 as 3 7/32 (3.218).  The History Parts book P&A 30H does not show either the 387 or the 100 as being removed from service, transferred, or substituted.

Steve

[big iron]

Ok, let's look at what we know about the 67 L78 alt. pulleys.

1- The pulleys where installed on the engine dress line so they would need a broardcast code for the line workers to install the correct pulley.
    Examples:  A- Z28 # 3829387 AI                    B- L78 # 3844100 AK
The 69 P&A Shows both these numbers to be correct service replacement #'s and for application, but probably without the #'s or broardcast code.
So, all NOS replacements should be incorrect if they do not have the #'s or broardcast code.

2- The 67 AIM A4 with a drawing date of 12/22/66 and a release date of 2/17/? shows that pulley # 3844100, fan # 3843346.and belt # 3849739 should be installed. The release date falls in-line with the 1st production of the L78 engine and there are no revisions recorded, but there could have been revisions around 05 that we do not have in the AIM. The 69 P&A backs all three numbers ( 3844100,3843346 & 3849739) as being good service replacements for the 67 L78 application.

3- The 69 P&A shows the Z28 (all sb) bellt # 3885047. 3/8 wide & 53 1/4 long and the L78 # 3849739, 3/8 wide & 55 1/2 long so the L78 belt is 3" longer. 
This brings up the question. will the in question pulley 3829387 AI even work with the correct belt #3849739? Some say it will not,I need to look into this.

4- The 69 P&A shows that the # 3843346 fan was used on all 67,68 applications. Single reinforcement rib, black with 11 blades and 5 11/16 dia. ?     

Bob

[plumL78]

Here are the results of what I came up with . We know of four survivor 67 L78 cars . 04B 4P,  06B , and two 07B cars.  One of the 07B cars is the orig owner still . All of them have the 4100 AK pulley.  The 04B and 06B cars have the four rivet fan. The 07B orig owner car has the five rivet fan. The other 07B car I do not know what it has. It was owned by Steve Schauger so maybe he can let us know if he has that information. The two pics. here are from one of the finest survivor cars you will ever find and it is the 06B car. It is the car the late Dave Minor owned and I believe it has 10k miles on it and it is a time capsule. So now we have one of the first 67 L78s with the 4100 pulley and a couple of the last with it along with and early four rivet fan and a late five rivet fan. thanks Kerry

[acelr8]

I believe that is the smaller fan and clutch not the 67-68 Z parts.That Z clutch is 7 1/2" in dia.Please correct me if I am wrong.Jeff