Replacement 68 340 four speed cams

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Brooks James said:
Hearsay is inadmissable, as well as polygraph results , in court. Lets see some hard evidence.
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His hard evidence comes from over 40 years of experience which includes using a degree wheel to measure camshafts. It's a pretty well known fact that a lot of the Mopar Performance camshafts don't measure anywhere near what the specs say. I've also verified that very thing many times in the past using a degree wheel. The "hard evidence" comes from years of experience and not given out on a silver platter on internet forums. It will come much better and stick with you much longer if you learn it yourself. Get a camshaft degree kit and learn to use it. They are very useful tools.
 
RustyRatRod said:
His hard evidence comes from over 40 years of experience which includes using a degree wheel to measure camshafts. It's a pretty well known fact that a lot of the Mopar Performance camshafts don't measure anywhere near what the specs say. I've also verified that very thing many times in the past using a degree wheel. The "hard evidence" comes from years of experience and not given out on a silver platter on internet forums. It will come much better and stick with you much longer if you learn it yourself. Get a camshaft degree kit and learn to use it. They are very useful tools.
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Then factor in that a small blocks acute pushrod angle never plots out like the cam says
 
crackedback said:
He's already got one MOPAR source for the correct specs that he can look up himself.

That performance manual is DEAD WRONG. But because someone wrote it it must be fact. Plenty of documents throughout history have misinformation in them that the masses take as facts.

A56 posted the correct and an incorrect set of values in this thread BOTH from MOPAR sources... at least the Race manual has the correct part number, but, they changed the grind from the originals.
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Are you saying that the original cam was superseded with different specs but the same part number ? If the Correct specs are published, where are they ? Lets see them ?
At this point if your saying that the DC "Bible"
Is wrong, then why wouldnt all other sources be in question ??
 
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340 Camshafts.jpg


Fun to see the 340 Camshaft specs here and the engines they were used in.
340, 4 bbl, Hydraulic, 430/444, 268/276 (automatic camshaft)

Surprised to see the '70 340 Six-Pack used the same automatic camshaft.
Also the 318, 4 bbl too.
360, 4 bbl engines too.

Like that they threw in the 318 Roller Cam comparisons in there too.

Here is the:
340, 4 bbl, ‘68 Manual Trans, Hydraulic Camshaft specs
444/453, 276/284
 
George Jets said:
View attachment 1715846790

Fun to see the 340 Camshaft specs here and the engines they were used in.
340, 4 bbl, Hydraulic, 430/444, 268/276 (automatic camshaft)

Surprised to see the '70 340 Six-Pack used the same automatic camshaft.
Also the 318, 4 bbl too.
360, 4 bbl engines too.

Like that they threw in the 318 Roller Cam comparisons in there too.

Here is the:
340, 4 bbl, ‘68 Manual Trans, Hydraulic Camshaft specs
444/453, 276/284
Click to expand...
Source ???
 
Brooks James said:
Are you saying that the original cam was superseded with different specs but the same part number ? If the Correct specs are published, where are they ? Lets see them ?
At this point if your saying that the DC "Bible"
Is wrong, then why wouldnt all other sources be in question ??
Click to expand...

it's in the 68 service manual, engine spec section... learn to fish... look it up yourself. You do a lot of questioning and very little personal research. Plenty led you to water, do you want to drink?

Many have posted other sources from MOPAR as well, somehow those aren't relevant yet the incorrect BS that MOPAR race bible put out is. Got it.
 
George Jets said:
View attachment 1715846790

Fun to see the 340 Camshaft specs here and the engines they were used in.
340, 4 bbl, Hydraulic, 430/444, 268/276 (automatic camshaft)

Surprised to see the '70 340 Six-Pack used the same automatic camshaft.
Also the 318, 4 bbl too.
360, 4 bbl engines too.

Like that they threw in the 318 Roller Cam comparisons in there too.

Here is the:
340, 4 bbl, ‘68 Manual Trans, Hydraulic Camshaft specs
444/453, 276/284
Click to expand...
The problem George is that those durations are only useful for comparing with other Chrysler cams.
We've discussed this in some threads with @Wyrmrider @crackedback and maybe @krazykuda
Chrysler, even in their promotional stuff and DC tech bulletins always put that out there. They never realy explained why.
From the actual cams measured, and from what Wyrmrider had seen working in the field, Chrysler degrees are based on the ramp change on the drawings.
IIRC there are enough original and aftermarket standard 340 cams we could come up .050 durations and estimate an .004 duration.
There's not true for original '68 manual transmission 340 cams. IIRC Rob had some measurements he has shared from his notes, as has Karl.
 
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This an exercise in rhetorics. I already the answers. I wanted to see how many different profiles/ specs were attributed to
Be the TRUE camshaft. Thanks guys for your loyaltyp
crackedback said:
it's in the 68 service manual, engine spec section... learn to fish... look it up yourself. You do a lot of questioning and very little personal research. Plenty led you to water, do you want to drink?

Many have posted other sources from MOPAR as well, somehow those aren't relevant yet the incorrect BS that MOPAR race bible put out is. Got it.
Click to expand...
Mattax said:
The problem George is that those durations are only useful for comparing with other Chrysler cams.
We've discussed this in some threads with @Wyrmrider @crackedback and maybe @krazycuda
Chrysler, even in their promotional stuff and DC tech bulletins always put that out there. They never realy explained why.
From the actual cams measured, and from what Wyrmrider had seen working in the field, Chrysler degrees are based on the ramp change on the drawings.
IIRC there are enough original and aftermarket standard 340 cams we could come up .050 durations and estimate an .004 duration.
There's not true for original '68 manual transmission 340 cams. IIRC Rob had some measurements he has shared from his notes, as has Karl.
Click to expand...
To many different Answers to know for sure.
 
LOL the 68 service manual is correct as is the 276/284 stuff that A56 and georgejets posted.

Go look up the part number in a 68 parts book section 9-15-1 IIRC
Then go to the 68 service manual and check the numbers,
then compare those # to a document (race manual) written a few years later that has a history of pimping and trying to sell mopar branded product to mopar folks.

Yeah, they aren't close to the same numbers, yet the smaller cam 268/276 cam was in production from 1968-1973 model years.

I believe, and measured cams that were in sync, with the service manual because those are the numbers service people had to use when diagnosing.
 
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George Jets said:
View attachment 1715846790

Fun to see the 340 Camshaft specs here and the engines they were used in.
340, 4 bbl, Hydraulic, 430/444, 268/276 (automatic camshaft)

Surprised to see the '70 340 Six-Pack used the same automatic camshaft.
Also the 318, 4 bbl too.
360, 4 bbl engines too.

Like that they threw in the 318 Roller Cam comparisons in there too.

Here is the:
340, 4 bbl, ‘68 Manual Trans, Hydraulic Camshaft specs
444/453, 276/284
Click to expand...


Brooks James said:
Source ???
Click to expand...


Those specs look like what is published in the service manuals... I'm updating a spread sheet that I put together for my own references, but when I originally did it, I didn't have all of the good years of service manuals handy... Now I have pretty much a full set ranging from 65 to 76... I am only up to reverifying 65 - 67 and I need to keep going, but time is short for me right now....

Plus I got myself side tracked on putting together a torque spec chart for engine bolts as I do the camshaft specs...
 
crackedback said:
LOL the 68 service manual is correct as is the 276/284 stuff that A56 and georgejets posted.

Go look up the part number in a 68 parts book section 9-15-1 IIRC
Then go to the 68 service manual and check the numbers,
then compare those # to a document (race manual) written a few years later that has a history of pimping and trying to sell mopar branded product to mopar folks.

Yeah, they aren't close to the same numbers, yet the smaller cam 268/276 cam was in production from 1968-1973 model years.

I believe, and measured cams that were in sync, with the service manual because those are the numbers service people had to use when diagnosing.
Click to expand...


The 268/276 cam was also used in the Lil Red Expresses for 78 and 79....
 
Brooks James said:
This an exercise in rhetorics. I already the answers. I wanted to see how many different profiles/ specs were attributed to
Be the TRUE camshaft. Thanks guys for your loyaltyp


To many different Answers to know for sure.
Click to expand...
it's more an exercise in futility, but we carry on.
 
krazykuda said:
The 268/276 cam was also used in the Lil Red Expresses for 78 and 79....
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Was it? or was just the same lifts?
We see the part numbers change in other engines that popularly are said to have '340 cams'.
And maybe those p/n changes mean nothing - something like a change of vendor.
Or they could have been changes in ramps and lobe shapes.
Look at the duration Ken used for the .006" tappet lift, and if I understand that's based on as close as he could make it to what he mapped.
340 cam specs?
So we know its more than that at .004 lift / .006 at the valve.
 
Hello all, I only had three truly interested parties and unfortunately that's not enough to get this project started. I'd like to get it going but it's not worth while for Jim and I to be able to even achieve a break even point. Blank cam core costs have risen over the past year so that puts us even further into how many need to be interested. I'm sorry I can't be of more assistance.
 
Frank, im definitely interested, put me down for one.
 
FWDLK Frank said:
Hello all, I only had three truly interested parties and unfortunately that's not enough to get this project started. I'd like to get it going but it's not worth while for Jim and I to be able to even achieve a break even point. Blank cam core costs have risen over the past year so that puts us even further into how many need to be interested. I'm sorry I can't be of more assistance.
Click to expand...
What if I had a 78 LRE core with a bad lobe, could this be reground back to original?
 
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