L88 Cam

[Michael H.]

Did early production 68 L88 Cars use the 1st design L88 cam that was used for 67 before the 3925535 cam was available? Possibly the 1st month of 68 production??

[Dick W.]

Re: L88 Cam

With the large spread between assembly date and installation in the cars I would tend to believe so, maybe even later.

[Ray K.]

Re: L88 Cam

I also tend to think that the earlier #3879605 camshaft would have been used for the early production of the 1968
L88's.

[Joe L.]

Re: L88 Cam

Did early production 68 L88 Cars use the 1st design L88 cam that was used for 67 before the 3925535 cam was available? Possibly the 1st month of 68 production??

Michael------


According to GM, yes. In fact, I think that most 1968 L-88 may have used the earlier cam.

[Michael H.]

Re: L88 Cam

Thanks guys. I think we agree. I don't think the 1st design cam was used for very long in 68 engines but I do think it was used for at least the first month or two.

Unfortunately, without some documentation, we may never know for sure.

Does anyone happen to have a known original cam from an early 68?

The 3879605 67 L88 cam was available from Crane cams years ago but I doubt if anyone sells it today. I supplied the correct cam for the Burroughs/Krughoff 12 mile 67 L88 decades ago. It came from Crane Cams.

[Dick W.]

Re: L88 Cam

?

The 3879605 67 L88 cam was available from Crane cams years ago but I doubt if anyone sells it today. I supplied the correct cam for the Burroughs/Krughoff 12 mile 67 L88 decades ago. It came from Crane Cams.

I don't have my books with me, but see if this cam is close Michael

CS-165R

BASE MODEL; Performance Cam; Pro-4000 Perf. Cam; Mechanical, (050) Duration at .050 Lobe Lift, 242 Exh., 242 Int., 114 Degrees Lobe Separation, 0.52" Exh. Valve Lift, 0.52" Int. Valve Lift

[Michael H.]

Re: L88 Cam

I don't have my books with me, but see if this cam is close Michael

Thanks Dick. I'll check it out. I have the original Specs for the 3879605 here.

[Clem Z.]

Re: L88 Cam

the 605 had a grooved rear cam journal so i would doubt the GM would use them in 68 blocks. all L-88 68 and up short blocks and complete engines i ever tore apart to blueprint had a 535 cam

[Joe L.]

Re: L88 Cam

the 605 had a grooved rear cam journal so i would doubt the GM would use them in 68 blocks. all L-88 68 and up short blocks and complete engines i ever tore apart to blueprint had a 535 cam

clem------

1967 blocks had the same rear cam journal machining as 1968 blocks.

[Clem Z.]

Re: L88 Cam

clem------

1967 blocks had the same rear cam journal machining as 1968 blocks.

i never had a 67 L-88 engine to work on and the cam in a 67 would not need the groove. i used the 605 in 66 short track 427 race engines as there were very few after market cams for BBC in 66.

[Michael H.]

Re: L88 Cam

i never had a 67 L-88 engine to work on and the cam in a 67 would not need the groove. i used the 605 in 66 short track 427 race engines as there were very few after market cams for BBC in 66.

Clem,

Pretty sure the original 3879605 cam from the Burroughs/Krughoff 67 L88 car had a grooved rear journal like a 65-66 cam even though it had a 67 style rear cam bearing.

You can use a cam with a grooved rear journal in a 67 and later block.

I think a lot of the over the counter 3925535 68-69 L88 cams also had the grooved rear journal.

[Michael H.]

Re: L88 Cam

I don't have my books with me, but see if this cam is close Michael

Dick,

I dug out the GM cam sheets for the 3879605 and 3925535 L88 cams but the checking clearance is @ .020" instead of the .050" on your chart so the numbers are not going to mean much.

I'll try to scan and post later.

[Richard L.]

Re: L88 Cam

I have a late 67 early 68 L88 new over the counter CE short block #321. It has a 3904367 cam in it, stamped 4367. Cam has no rear groove. Clem verified this as an L88 cam a while back.

[Michael H.]

Re: L88 Cam

I still can't find any numbers for lobe lift @ .050" but here's what I did have. Both the 67 (3879605) and 68-69 (3925535) cam specs are shown at .020".

The 67 was actually a bit nastier than the 68-69. Slightly higher lift and a bit more duration.