Camshaft swap

[Dave_EH]

Hi,

I presently have an unused cam (from an unstarted donor motor) that I have been intending to have put into my low milage stocko 179.

I was told by the seller it was a "30/70" cam, advanced 2 degrees (I assume that means its asymetircally timed?)

The spec sheet reads as: SAE (.006" Cam Lift) Cam Timing

 Â               Duration  Opens   Closes   Overlap
Inlet:        281           32         69          61
Exhaust:    281           72         29


It is a powerboss - part no. CS-1277

Can anyone decode these specs and verify the Cam?

From what I have picked up from using the forum, I now believe this cam may be a little lumpy for a daily driver.

I'm running a 2.7 diff.  I'm considering swapping the cam for something a little milder.

I'm after any opinion on:

1)what cam to use

2) whether it can be installed by removing the front grill rather than pulling out the engine - in order to save some dollars in workshop time...dialing in a cam is somehting I doubt I will ever try.

Looking forward to your thoughts
Dave ???

[fccool59]

30/70 should go fine with a 2:78 and 13" wheels

[HARKO]

Dave ,A mate had a 35/75 in a 3 speed HR and it was a pig to drive.
Also a mate runs a 30/70 with a celica 5 speed in an EH and its noticeable that its lumpy and has a noticeable power increase in its rev range when the cam starts to work.Id say its a bit lumpy to run an auto  transmission behind .
If you do decide on a swap Ive got a very mild cam in a 3000 klm 186/192 that id be willing to trade but will need a week or so to pull it out of the engine.
I will have a look for the spec sheets on the engine to find out its grind.
I guess yours being 32/72 it will just slightly lumpier than the 30/70

[Dave_EH]

Hey Harko,

I'm just running a 3 speed crash on the column.

I'be heard a 30/70 doesn't really start to pull till about 3000-3500 rpm which may be a little too high for an unbalanced red backed to a crash box.

so mine IS a 32/72? Being advanced would make it even more lumpy?

I'm in no real hurry - I would have to take my engine to a mechanic to have the cam pulled out for you as I have never done it before, so let me know how you're going when you find out the grind.

I've never driven an old holden - not even my own yet - so am trying to get the thing right from word go.

I'm really just after a nice sounding idle throb and something that has a little top end and a good mide range and take off.

Any ideas on installing the cam with the engine in the bay?

Dave

[HARKO]

Sorry Dave Ive never actually changed one in the engine bay ,Can anyone else help out here ,I would think that the grille is a pain to remove/install if need be.

[colt]

You can change the cam with engine in place on FE/C with grey motor. Remove grille, radiator. Lift front of motor slightly to clear subframe front rail.
Colin

[ChrisB]

Yep sure can change it in the car, but you also will need to undo the gaurd bolts to get the grille out without chipping the paint.
Having done it I certainly would not do it again as I was advised in the first place. I did it in the car as I did not have an engine crane.
I have since bought a crane and grey motor lifting frame. It made the job much easier when I had to rebuild the old grey. With the proper frame the grey comes out so so easy, about an hour or two and its on the deck.


ChrisB   8)

[Al]

Dave
           I always use a 25/65 grind cam with the 3.08 diff in the red motors or a 3.36 diff ratio behind the grey motors. If you use the 2.78 diff with the 3 speed it will be a lot harder to take off which will put a lot more strain on clutch and drivtrain. You can change the cam with motor in the car I,ve done lots of them. Do what Colin said .

       Cheers Al

[Dave_EH]

Appreciate the the help... all taken onboard!  Harko, I may contact you abou that cam, or let me know when you find the spec sheet.

Regards
Dave

[HARKO]

Hey Dave the cam I have is a lumpy aswell aparently so Id say give it a miss .

Anyone else keen to help please do !

[CHO 576]

I've got a similar problem/issue.

A mate did my grey motor up a few years ago now (free of charge).

However, he dropped a new cam in that is just a little bit lumpy. It has a nice little throb when idling, and very good performance up high (not sure of the exact specs of the cam though). Taking off from a standing start though is a bit of a hassle - I have to give the car a bit of petrol before it will even move (definately not a nice smooth takeoff)

Unfortunately, I have brougt the car back to be stock all round - so would really like to get the Original cam back in.

Is there anywhere I can $$$ buy a (new) 'original specification' grey motor cam?

thanks ...
J

[Dave_EH]

Thanks Harko,

I went down to my local engineering shop where they do camshaft grinds and headwork and had a chat.

They are happy to swap my unused cam for another milder one and said that a 32/72 is "drivable", but with a 3 speed it would be fairly ordinary except for putting your put down in 2nd or 3rd gear.

As i get further into the project I'm beginning to think less about pulling wheel stands and more about a nice cruiser ;D

I really just want something with a nice idle throb and some get up and go through the midrange.

Cheers
Dave