Crane CCH-312-2-NC

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72Duster440

72Duster440

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I finally pulled my cam out to see what it is, it's an old Crane CCH-312-2-NC. It's a single bolt cam that I can't find any specs on it, but I have found the specs for the 3 bolt version, which I will guess are the same, since I measure the duration and lift and it matched.

My question is, this cam is a 3,200 - 7,000 rpm cam that likes a 3500 stall converter and a cruise rpm of 4200+. I have since switched to a 4 speed, and am looking to regear to something a little taller to lower my highway RPMs, but I am wondering if I will have issues with driveability. I currently have an M1 single plane, but plan to go to a RPM Performer to help a little on the bottom end.

I am currently about 3650rpm @ 70 with a 26" tire and 3.91s, but I am looking to go to a 28" tire and either 3.73 or 3.55s to bring my RPM down to about 3k at 70.

Am I going to have any driveability issues with the lower rpm, or give up a bunch of power?

Here is the cam specs..

Crane Cams 684571 Crane Hydraulic Flat Tappet Camshafts | Summit Racing
 
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CCH-312-2-NC = .528/552 242/252 @ .050 on a 108.
 
It's 108? The 3 bolt version they have is a 112. I degreed it in on a 108 when I put it back in.

Screenshot_20240126_174443_Drive.jpg
 
I agree, I had some trouble finding this one, I called Crane's number, but they are apparently out of business and the number went to Edelbrock, which were useless. What do you have that shows it as a 108? Maybe I should have advanced it more then to bring the power band in sooner?
 
With 3.55’s. It’ll be sluggish off the line and have what seems like a slow climbing tachometer. It’ll feel like a slow motion jump that just keeps on going up. You’ll wait a while for a gear change BUT will notice that it happens much later on the MPH read out. Your top end will seem like, forever getting there and limitless.

Find a calculator
 
Do you have heads capable of making power up around 7000 rpm?
 
72Duster440 said:
I agree, I had some trouble finding this one, I called Crane's number, but they are apparently out of business and the number went to Edelbrock, which were useless. What do you have that shows it as a 108? Maybe I should have advanced it more then to bring the power band in sooner?
Click to expand...
There was a small block one for sale here a while back that shows up on a search. It was on a 108. They would not have changed that grind just because it was for a big block.
 
That cam is in my 1984 Crane Catalogue. LSA is 112. First words in the description are 'Rough idle'. The problem with a 4 speed is going to be surging, pig rooting at low rpms, as well as the rough idle. Removing the c'ter removes the hydraulic cushion you had in the drive line to absorb surging etc.
If it was my engine, I would use an Isky 280 Mega or even the next size down. It will pump up the low/mid range where you are cruising.
The 440 is unique among the big blocks in that it has the highest rod/stroke ratio. In layman's language, it means it does not tolerate long duration cams as well as other brands.

Sig Erson was ware of this DECADES ago & warned of this in his catalogue, 440 page.

img282.jpg
 
Bewy said:
That cam is in my 1984 Crane Catalogue. LSA is 112. First words in the description are 'Rough idle'. The problem with a 4 speed is going to be surging, pig rooting at low rpms, as well as the rough idle. Removing the c'ter removes the hydraulic cushion you had in the drive line to absorb surging etc.
If it was my engine, I would use an Isky 280 Mega or even the next size down. It will pump up the low/mid range where you are cruising.
The 440 is unique among the big blocks in that it has the highest rod/stroke ratio. In layman's language, it means it does not tolerate long duration cams as well as other brands.

Sig Erson was ware of this DECADES ago & warned of this in his catalogue, 440 page.

View attachment 1716198058
Click to expand...
I don't believe that's the same grind number he has, but if it is I stand corrected.
 
I also have a 2010 Crane catalog. Both cams are listed, 112 LSA & 108 LSA. 112 cam grind# is
H-312-2; 3200-7000 rpm range. 108 # is H-242/3520-2-8; 3600-7200 rpm range. So I think it is the 112.
Crane had an epiphany after D. Vizard tested 000s of cam combinations for him & the result is many more cams in the catalogue are on tighter LSAs.
 
Bewy said:
I also have a 2010 Crane catalog. Both cams are listed, 112 LSA & 108 LSA. 112 cam grind# is
H-312-2; 3200-7000 rpm range. 108 # is H-242/3520-2-8; 3600-7200 rpm range. So I think it is the 112.
Crane had an epiphany after D. Vizard tested 000s of cam combinations for him & the result is many more cams in the catalogue are on tighter LSAs.
Click to expand...

Thanks, it's should be 112 then, the grind number on the cam was 312-2.


I'll hold off on the regear for now. I have no driveability complaints with it with a 4 speed and a 26" tire as long as I keep the revs above 2500 or so while cruising, below that it struggles. I used to have a 28 inch tire, but don't remember how it liked lower rpm, and it was an auto at the time.

I think ideally you are correct and a new cam should get installed, it's just not in the budget currently. I did have my eye on the Isky 264 Mega grind though. This is just a street car, I don't ever plan on racing it, so not too concerned with top end power.
 
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72Duster440 said:
I finally pulled my cam out to see what it is, it's an old Crane CCH-312-2-NC. It's a single bolt cam that I can't find any specs on it, but I have found the specs for the 3 bolt version, which I will guess are the same, since I measure the duration and lift and it matched.

My question is, this cam is a 3,200 - 7,000 rpm cam that likes a 3500 stall converter and a cruise rpm of 4200+. I have since switched to a 4 speed, and am looking to regear to something a little taller to lower my highway RPMs, but I am wondering if I will have issues with driveability. I currently have an M1 single plane, but plan to go to a RPM Performer to help a little on the bottom end.

I am currently about 3650rpm @ 70 with a 26" tire and 3.91s, but I am looking to go to a 28" tire and either 3.73 or 3.55s to bring my RPM down to about 3k at 70.

Am I going to have any driveability issues with the lower rpm, or give up a bunch of power?

Here is the cam specs..

Crane Cams 684571 Crane Hydraulic Flat Tappet Camshafts | Summit Racing
Click to expand...
Hello from Shelby Mi.
 
72Duster440 said:
Thanks, it's should be 112 then, the grind number on the cam was 312-2.


I'll hold off on the regear for now. I have no driveability complaints with it with a 4 speed and a 26" tire as long as I keep the revs above 2500 or so while cruising, below that it struggles. I used to have a 28 inch tire, but don't remember how it liked lower rpm, and it was an auto at the time.

I think ideally you are correct and a new cam should get installed, it's just not in the budget currently. I did have my eye on the Isky 264 Mega grind though. This is just a street car, I don't ever plan on racing it, so not too concerned with top end power.
Click to expand...
Where was the ICL prior to removing the cam? There are MANY things that can help/affect drivability. If you were solely going on 'no changes' other than 'installing the cam where it wants to be in-theory' then you should be certain where it was prior to removing it for comparisons sake.
 
72Duster440 said:
It was 108, I measured before and after to ensure it was the same, as it runs amazing as is.


I am looking at one of these setups now, to make it more of a street pounder.

1969 DODGE COMP Cams K21-224-4 COMP Cams Xtreme Energy Cam and Lifter Kits | Summit Racing

or the kit that comes with this one.

1969 DODGE CHARGER COMP Cams 21-223-4 COMP Cams Xtreme Energy Camshafts | Summit Racing
Click to expand...
GOOD work! If it's decent now, I'd lean towards leaving it alone and focusing on the other many elements for improvement. Mainly because getting a flat tappet cam to not go flat recently is an issue. I wouldn't be afraid to advance it more to enhance lower-end power. You should feel even 2 degrees change. If the motor has good quench .04-.052" it'll tolerate some spark advance. If it doesn't...put a gasket on it now to make it 'good'. Then the carb has a whole range of tune to it that'll help. In a 440 with production heads that cam will probably loose power over 5500 FWIW.
 
72Duster440 said:
It was 108, I measured before and after to ensure it was the same, as it runs amazing as is.


I am looking at one of these setups now, to make it more of a street pounder.

1969 DODGE COMP Cams K21-224-4 COMP Cams Xtreme Energy Cam and Lifter Kits | Summit Racing

or the kit that comes with this one.

1969 DODGE CHARGER COMP Cams 21-223-4 COMP Cams Xtreme Energy Camshafts | Summit Racing
Click to expand...
Do you mind detailing the motor and car? I assume it's a 440 in a Duster?
 
72 Duster, 10.5:1 440, 915 heads, 833, 3.91, 26" tire.

It was built when it was an auto with a 28" tire and 3500 stall and was a bracket racer.

Runs and drives great now, but lugs a bit and loads up under 2500 rpm. Trying to drop my highway cruise RPMs a bit, but not sure the current setup will work with around town driving then.
 
72Duster440 said:
It was 108, I measured before and after to ensure it was the same, as it runs amazing as is.


I am looking at one of these setups now, to make it more of a street pounder.

1969 DODGE COMP Cams K21-224-4 COMP Cams Xtreme Energy Cam and Lifter Kits | Summit Racing

or the kit that comes with this one.

1969 DODGE CHARGER COMP Cams 21-223-4 COMP Cams Xtreme Energy Camshafts | Summit Racing
Click to expand...
Do you happen to know your compression ratio? Or, do you have (or can you get) your cylinder pressure as-is?

Would hate for you to cam down and push your cylinder pressure too high.
 
I do not know my current cylinder pressure, but could check it. My compression ratio is 10-10.5:1 with a set of flat tops in it.
 
Good point, maybe I want to get the bigger Comp one that is still low rpm / street friendly.

I will say, I do love the choppy rough idle I have now, it'll be a bummer to lose it.
 
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