RustyRatRod's Guide To Hot Rod Bliss

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Captainkirk said:
OK...I have been waiting patiently (for like a year) for Rob & Rob's Guide to Building a Low-Budget Kickass 340, but alas...we've covered Everything But.
The stocker '68 four speed was 275HP...surely we can do better than that with a few minor tweaks, no? Don't keep us waiting any longer, fellas!
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The only thing you need to do to a 340 is more carburetion or gears. Why are they Legendary? Because they were the best all around engine ever produced, as is. The "68" 340 4 speed would go into the 12's. Put a Thermo-quad carb and intake and they will really fly. NHRA had the "71" factored up in the 325hp range or even higher, and that was before they allowed you to port the heads. With the right gears you could get 20 mpg or beat a 365hp 327 4 speed Nova by 6 car lengths. And that was a daily Driver, what more do you want to do? Doesn't get any more low buck than that.
 
66fs said:
The only thing you need to do to a 340 is more carburetion or gears. Why are they Legendary? Because they were the best all around engine ever produced, as is. The "68" 340 4 speed would go into the 12's. Put a Thermo-quad carb and intake and they will really fly. NHRA had the "71" factored up in the 325hp range or even higher, and that was before they allowed you to port the heads. With the right gears you could get 20 mpg or beat a 365hp 327 4 speed Nova by 6 car lengths. And that was a daily Driver, what more do you want to do? Doesn't get any more low buck than that.
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I'm intending on using a TQ and 3.91 gears with the four speed....
 
So....you're saying the '68 340 four speed cam grind is the best all-around for this motor?
 
As others have said, the stock 68 to 73 340 cam is very good. You can tell by it's sound it is a performance cam. It Idles well, comes on like a freight train about 3,000 rpm, and will pull above 6,000 rpm and get there quick. The 68 manual transmission cam is a step bigger. I have no personal experience with that cam other than a friends 68 4 speed Fastback Barracuda. The 340 cam was upgraded some time in the 70's? for a faster rate, more duration at .050" lift. When I rebuilt a 273, 318, 340, or 360 engines for friends street cars I would use the standard 68-73 340 cam. Never a complaint. All that said, can you use a newer grind with about the same duration? Yes. On lift, the thing to remember is that stockish heads max flow is around .450 lift. In my opinion, I will rarely go to a higher lift than that. If you have heads that more flow at higher lifts, then you can adjust your cam to take advantage of that. However everything, changes at that point. I use factory positive valve seals and new or used 340 single valve springs, no special machining or parts. The bottom line is, I run street cars that go anywhere, last forever, are pretty fast and still get good gas mileage. A cam is the heart of your engine. Honestly decide what you want long term. Feel free to talk to cam grinders, custom grinds are not that expensive.
 
66fs said:
As others have said, the stock 68 to 73 340 cam is very good. You can tell by it's sound it is a performance cam. It Idles well, comes on like a freight train about 3,000 rpm, and will pull above 6,000 rpm and get there quick. The 68 manual transmission cam is a step bigger. I have no personal experience with that cam other than a friends 68 4 speed Fastback Barracuda. The 340 cam was upgraded some time in the 70's? for a faster rate, more duration at .050" lift. When I rebuilt a 273, 318, 340, or 360 engines for friends street cars I would use the standard 68-73 340 cam. Never a complaint. All that said, can you use a newer grind with about the same duration? Yes. On lift, the thing to remember is that stockish heads max flow is around .450 lift. In my opinion, I will rarely go to a higher lift than that. If you have heads that more flow at higher lifts, then you can adjust your cam to take advantage of that. However everything, changes at that point. I use factory positive valve seals and new or used 340 single valve springs, no special machining or parts. The bottom line is, I run street cars that go anywhere, last forever, are pretty fast and still get good gas mileage. A cam is the heart of your engine. Honestly decide what you want long term. Feel free to talk to cam grinders, custom grinds are not that expensive.
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These are my old cam specs. Not a lot of lift but lots of duration and overlap. While I loved the lumpy idle, I was not so thrilled with the low vacuum at idle/off idle and want to tone this build down some for a more streetable ride as was mentioned in the beginning of this thread. I'm not a punk kid anymore and don't foresee racing it, and I've dropped the compression down to a more reasonable 10:1 so the big bumpstick isn't necessarily on the menu anymore.

10595228446_39df37fd60_z.jpg
 
Abodybomber said:
,

No wife,to villify,Rob .... The "over cammed ,over converted,too big a cylinder head," ,I 've done....I ended up,with a Mopar,in trade.....She*t happens,lick your wounds...
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My reply was aimed at the intended HP level listed by the previous poster which was 650 - 700 hp.

I later joked about selling the wife's car. Not making a villian out of anyone or thing.
 
Captainkirk said:
These are my old cam specs. Not a lot of lift but lots of duration and overlap. While I loved the lumpy idle, I was not so thrilled with the low vacuum at idle/off idle and want to tone this build down some for a more streetable ride as was mentioned in the beginning of this thread. I'm not a punk kid anymore and don't foresee racing it, and I've dropped the compression down to a more reasonable 10:1 so the big bumpstick isn't necessarily on the menu anymore.
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My first 273 build was a solid 284 duration .450 lift cam. The Direct Connection Manual used to say the biggest cam for a street car was the Street Hemi Grind, about 284 duration and .480 lift. They later updated it, same lift but 280 duration and faster rates. Supposedly better lower end and vacuum with no loss at the top. Your cam is a big cam. I use solid cams in my own cars, typically a Racer Brown or Isky cam. Proven designs and they hold up well. I'm building a 72 340 and I'm going to use a Racer Brown ST2, 218 duration at .050" with .450 lift. If I was going hydraulic I'd just use the 340 cam. Why not start your own thread giving as much information you can and see where it goes?
 
66fs said:
My first 273 build was a solid 284 duration .450 lift cam. The Direct Connection Manual used to say the biggest cam for a street car was the Street Hemi Grind, about 284 duration and .480 lift. They later updated it, same lift but 280 duration and faster rates. Supposedly better lower end and vacuum with no loss at the top. Your cam is a big cam. I use solid cams in my own cars, typically a Racer Brown or Isky cam. Proven designs and they hold up well. I'm building a 72 340 and I'm going to use a Racer Brown ST2, 218 duration at .050" with .450 lift. If I was going hydraulic I'd just use the 340 cam. Why not start your own thread giving as much information you can and see where it goes?
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LOL...I have a thread going...10 years and 40-something pages, in case you missed it...
Captainkirk's Duster project
 
Thanks to Karl, Oregon Cam Grinders has the 68 only 340 4 speed cam specs and will grind to order.

Remember, the 68 4 speed cam was different than the 69 and up.
 
Captainkirk said:
LOL...I have a thread going...10 years and 40-something pages, in case you missed it...
Captainkirk's Duster project
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I do know, but thought you wanted to narrow your specific cam/engine discussion. I was surprised that no one else has offered opinions on cam selection or a 340 build. But then this is RRR's attempt to generally help people to avoid the temptation of big Horsepower and dissatisfaction of trying to drive a race motor on the street.
 
Generally speaking, IMO, while it is not the biggest cam one could live with on the street it is a typical go to type of cam that is capable of making a really nice street machine with HP & TQ to satisfy the need and have the abilty to cruise the streets everywhere with power everything.

A cam with 230*'s of duration @.050 is generally a 2000-6000 rpm cam in a small block.
 
66fs said:
I do know, but thought you wanted to narrow your specific cam/engine discussion. I was surprised that no one else has offered opinions on cam selection or a 340 build. But then this is RRR's attempt to generally help people to avoid the temptation of big Horsepower and dissatisfaction of trying to drive a race motor on the street.
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OK, understood. Yes, I'll start a separate thread for that so as not to hijack Rusty's thread here. Thanks for the suggestion.
 
RustyRatRod said:
Thanks to Karl, Oregon Cam Grinders has the 68 only 340 4 speed cam specs and will grind to order.

Remember, the 68 4 speed cam was different than the 69 and up.
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RRR how would the 68 340 4 speed cam work in a 73 340 bored 20 over? 587 heads ported 2.02 intake 1 5/8 headers 3.91 rearend auto trans tight 3000 t c ?
 
RustyRatRod said:
Thanks to Karl, Oregon Cam Grinders has the 68 only 340 4 speed cam specs and will grind to order.

Remember, the 68 4 speed cam was different than the 69 and up.
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Yes, the master of mine that he used was just a little off on the intake C/L, and only .006" short of the intake lift (not very much). I bought it from a member who had it custom ground by another grinder...

The one that he made off of it, he adjusted the intake lobe, so it fits the stock 68 340 4 speed cam exactly, but just .006" less intake lift, the exhaust lift is right on...

Call Oregon cam grinders and Ken Heard should be able to hook-up anyone who wants one... He has a master to make it from now...
 
christmas53 said:
RRR how would the 68 340 4 speed cam work in a 73 340 bored 20 over? 587 heads ported 2.02 intake 1 5/8 headers 3.91 rearend auto trans tight 3000 t c ?
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I think it would be fine. What is the static compression?
 
RustyRatRod said:
... Carburetor. I gotta be honest here. Carburetors can be somewhat complex for a beginner.....hell I still have some give me fits today. Sometimes you just get a bad one. But I strongly recommend finding a good used core and building one yourself. You will learn it yourself and you will save money. What's not to love about that? I can get a kit for most Holleys and AFB and AVS styles for under 30 bucks. Thermoquad kits are usually around 50...
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Almost any OEM Mopar 4 barrel carb works great as long as all the parts are not corroded in place and water has set inside the bowls. They have the right linkage, pretty close to the right mixture (typically 3 steps on primary rods), and simple choke functions. The best are the ones covered in oil, has all it's parts intact, and no one has rebuilt (ruined) including major rebuilders. The best were on factory High Performance engines, 273 340 383 400 440. These were calibrated closest to the type of engine we want to build. Mopar used the AFB, AVS, TQ, QJ, and Holley. My favorites are the AVS, TQ, QJ. These three have an infinitely Adjustable Air Valve to regulate air to the secondaries. The TQ and QJ have small primaries and huge secondaries which give them great drivability and gas mileage with no penalty when the pedal goes to the floor. As RRR said, some times you just get a bad one, but usually you can save a lot of time and money by picking up one of these carbs used. Clean it up, put a Kit in it, return it to specs, and finally tune it for your combo. And once your done, it won't require constant maintenance or tweaking.
 
Thanks for the kind words, yall. Lemmie ask yall. Would yall be interested in some recipes I concoct off Desktop Dyno? I could do like a 300, 350, 375 and 400 HP version of small blocks. I realize it's "just" a computer program, but remember, the more variables that go in, the better at what comes out. Just a thought.
 
RustyRatRod said:
Thanks for the kind words, yall. Lemmie ask yall. Would yall be interested in some recipes I concoct off Desktop Dyno? I could do like a 300, 350, 375 and 400 HP version of small blocks. I realize it's "just" a computer program, but remember, the more variables that go in, the better at what comes out. Just a thought.
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That would be fantastic.
 
maybe, you could do a desktop for the taxicab 383, say 400 hp. they are not a taxicab motor, though some might think.
 
I will do one tomorrow and post it. I am not doing this to have a frikkin war. Just for some guidelines. If people want to critique it all to pieces, there won't be a second.
 
RustyRatRod said:
I will do one tomorrow and post it. I am not doing this to have a frikkin war. Just for some guidelines. If people want to critique it all to pieces, there won't be a second.
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I had a friend that bought a new 1966 chevy 2 w/ a 365 horse 327-4 speed-posi trac, no power anything, or air. there weren`t "any" tires that would come close to holding that thing. there is no way any stock 340 would have out run that car. I`ve been around a few 340`s, had a 330 horse barracuda that would out run 340`s back then. gotta disagree on this one . that 327 would anialate a 67 375 horse gtx too. matter of fact, the car was never out run back then.
 
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