340 questions

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so i was out in the shed today and found this cam/lifter set new in the box. forgot i had it. picked it up with a 360 package a couple years ago.

is this what the 340's came with? from what i understand it will be out of gas at about 5000rpm.. this correct? if this is a stock 340 cam and its done at 5000 rpm then all are all those high winding stock 340 stories i've heard over the years bullshit? was wondering is this would be a good option for this 340.

cam 340.JPG


IMG_20230114_145957.jpg
 
abodyjoe said:
so i was out in the shed today and found this cam/lifter set new in the box. forgot i had it. picked it up with a 360 package a couple years ago.

is this what the 340's came with? from what i understand it will be out of gas at about 5000rpm.. this correct? if this is a stock 340 cam and its done at 5000 rpm then all are all those high winding stock 340 stories i've heard over the years bullshit? was wondering is this would be a good option for this 340.

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stock 340 rev to 6k
peak power around 5300 ish
shift rpm is higher 5500 rpm depending on rear gear
 
abodyjoe said:
so i was out in the shed today and found this cam/lifter set new in the box. forgot i had it. picked it up with a 360 package a couple years ago.

is this what the 340's came with? from what i understand it will be out of gas at about 5000rpm.. this correct? if this is a stock 340 cam and its done at 5000 rpm then all are all those high winding stock 340 stories i've heard over the years bullshit? was wondering is this would be a good option for this 340.

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That is the 340 automatic grind. It will pull well past 5,000 rpm if set up right with the right valve springs. Worth good money now I would expect.
 
66fs said:
That is the 340 automatic grind. It will pull well past 5,000 rpm if set up right with the right valve springs. Worth good money now I would expect.
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yea? the victory site says its a std shift cam.. they have the wrong info?

Note: original standard-shift high-performance 340 4bbl. cam
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Worth good money now I would expect.
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hmmm.. maybe i should put it up for sale.
 
abodyjoe said:
i picked the motor up tonight. as longs as i measured right its std bore. the rods with no pistons are the original rods. the pistons and rods the seller got from a friend. steel crank drilled for a pilot bearing.. got a windage tray, oil pan and timing cover with it. now i just have have to figure out how to build it. want it to run like a 340 is supposed to and be a nice cruiser with the 3.23 gears that are in the car. I'll use the 340 manifolds i have on the car now along with the performer rpm (non air gap) intake i have. I'll also use one of the sets of J heads i have.

casting date looks to be 1-13-71 or maybe 1-15-71. not sure what the vin is from.

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That engine is from a 72 model year car from the VIN on it, but there's nothing wrong with that...

I would get new rod bolts and have them installed on the rods and remachine the crank bores so they are properly matched.... Rod bolts should only be torqued 5 times before replacing them so they don't get overstretched and break on you under stress... You don't know how many times those have been tightened and retorqued.. They have at least two torque cycles right from the engine factory and you don't know if anyone has tightened them afterwards...

Then find a nice set of 9.0 - 9.5 compression pistons...
 
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abodyjoe said:
so i was out in the shed today and found this cam/lifter set new in the box. forgot i had it. picked it up with a 360 package a couple years ago.

is this what the 340's came with? from what i understand it will be out of gas at about 5000rpm.. this correct? if this is a stock 340 cam and its done at 5000 rpm then all are all those high winding stock 340 stories i've heard over the years bullshit? was wondering is this would be a good option for this 340.

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View attachment 1716034875
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I would go a little larger than that, but no larger than the MP .484" lift 284 duration...
 
abodyjoe said:
yea? the victory site says its a std shift cam.. they have the wrong info?






hmmm.. maybe i should put it up for sale.
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If you sell it, sell the cam and keep the lifters... Those are probably the good lifters before they went to ****...
 
abodyjoe said:
yea? the victory site says its a std shift cam.. they have the wrong info?






hmmm.. maybe i should put it up for sale.
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I worked with Oregon Cams and had a close replica of the stock 68 340 4 speed cam made and it's available...

Read here for details:

Reproduction 340-4 Speed Cam
 
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Stock 340 auto cam or 69+ cam however you want to call it.

That cam might spin past 5200-5300, they don't make any more power over that.

Agree on the lifters, keep them.
 
abodyjoe said:
is the 4 speed cam really anything special?
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Take the auto cam exh lobe, put it on the intake and the 440 mag intake lobe and put on exh... that's the 4 speed cam.

Outside that it is the OEM style cam that came in 68 cars, special, Not IMO. If I'm buying a new cam because I want much better performance from a 340, it isn't going to be that one unless some class rule requires an absolutely stock camshaft. Is it slightly better than the Auto cam, yeah, might get you another 200 RPM power to 5400-5500.
 
they have both run well
the auto cam can run high12s low 13s in a lighter A-body
the 4spd cam slighty better
there are better choices for a cam today
no stall stay under 220@50 with 3.23s
i put a 218@50 454 110 lsa comp cam in a stock 100k mile 340 lower end around 1991
had a fresh set of 2.02 heads thin head gasket dc said good for 1/2 point 169 psi cranking comp alum weiand dual plane 650 dp and a unilte 3.23s 235 60 14s in a 67 dart ragtop
motor tranny 8 3/4 came out of 68 gts with 85k on it ran 14.3 97 mph all stock
smallest cam i ever had its a great street cam for 3.23s not a 904 lifter cam
pulled much better then the stock cam good low end pulled hard to 5800 rpm
dead stop punch smoke the tires 45 feet in 1st 8 feet in 2nd if i wanted with 3.23s id guess 13.9 compared to 14.3 when it was in the gts
now it has 3.91s and a traction problem burn all the way thru 1st and 2nd on a dead stop punch id guess 13.7 now
great street cam imo
i would however by a cam now that uses the mopar 904 lifter
 
abodyjoe said:
yea? the victory site says its a std shift cam.. they have the wrong info?






hmmm.. maybe i should put it up for sale.
Click to expand...
Lots of bad info on the internet. I only run custom Racer Brown solid cams anymore. I set limits on what I want in an engine. They are Factory exhaust manifolds, single valve springs, OEM viton positive valve seals, .500 in max lift cam, no square lobes that are hard on the valvetrain, 3.91 max gears, compression to run 91 octane gas. As far as selling the 340 cam, I think they have been discontinued, there are people who have a soft spot for the 340. Looks like they go close to $500 for the kit. Nothing like calling a cam grinder with all your exspectations and specs to have them grind you an optimum piece for you.
 
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