Cam for the 81

[big2bird]

I was planning on installing an ECM compatible cam in the 81 someday. Just maybe one step up from the stock universal crate engine in there, to insure I would pass the Ca smog test. Now that Crane is closing, maybe I should buy one from Summit while they still have stock. So, anyone suggest a part # for me? Nothing wild, just a step up.(My car has ALL the stock smog/ecm stuff).

 

[73 Mike]

I'll be interested in hearing what people come up with. Before I sold my 81, I went through the same exercise trying to find a cam to wake it up a little. I spent some time on the phone with a couple of different cam companies. Finally, I found a guy at Comp Cams that suggested I leave the cam alone and go to 1.6 rockers. Ultimately, the issue appears to be overlap. If you significantly increase overlap, the computer will go insane.:gurney:

The increased lift from the 1.6 rockers will give you a little more flow (assuming that this doesn't give you coil bind). Never did it so can't tell you if the difference is even noticeable.

 

[MYBAD79]

What's the specs of the cam that you have now and what's the CR of that crate engine ?

The stock L82 cam isn't all that bad, depending on what you have now that might be a good option.

 

[big2bird]

What's the specs of the cam that you have now and what's the CR of that crate engine ?

The stock L82 cam isn't all that bad, depending on what you have now that might be a good option.

.383"/.401" 194*/202* with 112* LSA 8.5-1 CR

Stock L-81 engine was:

.381"/.403" 196*/204* with 113* LSA 8.5-1 CR

 

[mrvette]

What's the specs of the cam that you have now and what's the CR of that crate engine ?

The stock L82 cam isn't all that bad, depending on what you have now that might be a good option.

.383"/.401" 194*/202* with 112* LSA 8.5-1 CR

Stock L-81 engine was:

.381"/.403" 196*/204* with 113* LSA 8.5-1 CR

Bird, be ME, I would try the 1.6 rocker route, and if you have smog problems, just change them back again.....in fact, easy enough to change when checking time comes....

:3rd:

 

[big2bird]

What's the specs of the cam that you have now and what's the CR of that crate engine ?

The stock L82 cam isn't all that bad, depending on what you have now that might be a good option.

.383"/.401" 194*/202* with 112* LSA 8.5-1 CR

Stock L-81 engine was:

.381"/.403" 196*/204* with 113* LSA 8.5-1 CR

Bird, be ME, I would try the 1.6 rocker route, and if you have smog problems, just change them back again.....in fact, easy enough to change when checking time comes....

:3rd:

Alot of wisdom there. Part#?

 

[big2bird]

Crane shows 2 choices (Computer compatable):

#114122:

.423"/.426" 204*/214* 110*LSA

#114132

.440"/.454" 210*/216* 114*LSA

 

[big2bird]

When I installed the crate engine, I didn't replace the POS link belt with a true roller. I know someday, maybe 5 years, I will have to change it. I'll pull it to do that, vs fighting it in the car.
The cam with lifters is only $167. A set of 1.6 rockers is $200, and easy to change. A set of nice roller rockers is $323. I'm not so sure I would like to set up rollers in the car. I'd rather do that on a stand to check the geometry.
Decisions, decisions..........

 

[mrvette]

When I installed the crate engine, I didn't replace the POS link belt with a true roller. I know someday, maybe 5 years, I will have to change it. I'll pull it to do that, vs fighting it in the car.
The cam with lifters is only $167. A set of 1.6 rockers is $200, and easy to change. A set of nice roller rockers is $323. I'm not so sure I would like to set up rollers in the car. I'd rather do that on a stand to check the geometry.
Decisions, decisions..........

I just glad most of those decidions were made some 12-15 years ago, hate the thought of repeating the process today....:crutches:

 

[MYBAD79]

The rockers might be the better choice but check your springs. Valve lift with 1.6 rockers increases from .383" and .401" to .408" and .427".
Summit part numbers: SUM-G6801, PRO-67300, $60 for a set stamped steel rockers. Summit also has a set of 1.6 roller tip rockers for $90.
The low compression, computer and the smog testing don't make it easy. The L82 cam is somewhere around 220 duration so passing smog SHOULD be ok with a cam of that duration or the two you listed above, however... the L82 has higher compression to make the hotter cam work, how does the higher CR affect emissions ? dunno....
One more thing to consider is cam break in and lifter/lobe failure.... get the rockers for $60 if the springs allow additional lift and leave the rest alone for now, I don't think the cam will make a huge difference with your low CR.

 

[big2bird]

The rockers might be the better choice but check your springs. Valve lift with 1.6 rockers increases from .383" and .401" to .408" and .427".
Summit part numbers: SUM-G6801, PRO-67300, $60 for a set stamped steel rockers. Summit also has a set of 1.6 roller tip rockers for $90.
The low compression, computer and the smog testing don't make it easy. The L82 cam is somewhere around 220 duration so passing smog SHOULD be ok with a cam of that duration or the two you listed above, however... the L82 has higher compression to make the hotter cam work, how does the higher CR affect emissions ? dunno....
One more thing to consider is cam break in and lifter/lobe failure.... get the rockers for $60 if the springs allow additional lift and leave the rest alone for now, I don't think the cam will make a huge difference with your low CR.

The idea is to but a part of the Crane legacy for a future project. I can buy Summit crap anytime.
Let's focus on which cam would let me still pass smog. I figure as long as the cam works with the ecm, the computer and ECM carb will do the rest. Right now, with the Magnaflow converter, it's well within limits.

 

[MYBAD79]

The idea is to but a part of the Crane legacy for a future project. I can buy Summit crap anytime.
Let's focus on which cam would let me still pass smog. I figure as long as the cam works with the ecm, the computer and ECM carb will do the rest. Right now, with the Magnaflow converter, it's well within limits.

Both of the cams you listed should let you pass smoke, at least that's what the ad says. Is it going to be worth the effort ? I doubt it. Just my opinion: if you want a Crane cam for a future project then buy one of their roller cams.