Free cam build...

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Well, after looking a little closer, there are several of the modern manufactured cams that come very close to matching the timing events of that cam, but they are all spec'd as drag race cams. Build accordingly and it will make some big numbers. Cylinder heads will be everything, especially if you build a 4 inch stroke engine. I would probably go with a 360 to save as much $$$ as I could for proper heads.
 
Not sure I’d use a 4” arm. That would be a whole lot of piston speed at 7000+ rpm. I like the idea of a 340 stock stroke with the tunnel ram and big headers. It’s gonna suck to drive around on the street though. Unless you live in a town with straight roads and no fuzz.
 
If you ever do run it on the street, plan on learning to live with at least 4.56:1 gears.
 
I have 4:10’s in the car now and did drag week with it...I also have a set of 4:56s so no problem
 
Not sure I’d use a 4” arm. That would be a whole lot of piston speed at 7000+ rpm. I like the idea of a 340 stock stroke with the tunnel ram and big headers. It’s gonna suck to drive around on the street though. Unless you live in a town with straight roads and no fuzz.
I’m not sure I’m worried about piston speed... I have friends with W8 headed small blocks and they spin the **** out of them with 4 inch cranks...
 
If it’s a 340, it needs good heads, good rocker gear with geometry corrected, and at least 12-1/2:1 compression, 1-3/4 headers and 340 Victor with an 850-930 cfm carb.A tunnel ram with a pair of 4150 750s would really make it shine. It would be an interesting test rig to compare an M1 tunnel ram to an older edelbrock TR5 and a Weiand TR.
But if you just put some 273 heads on that sucker it'll be plenty streetable.
Restrictor plate style.
 
The cam choice has turned every one off.
Sunk from the start.
Red alert!
Must abort thread!
LoL
Id use a 360 block.
The thought of destroying a 340 block at high rpm with a 4" rotating assembly....

now can someone direct me to the "free streetmaster intake engine build" thread and then the "free quadrajet carb engine build" thread afterward.... or how about the opposite end of the spectrum ehh...
The "free stock 318 piston engin build" thread .... wonder if it will catch on beyond to "free chewed gum" .. thanks, seriously funny to read reactions to your build.
 
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I’m not giving up on this free cam!!! 10 second street time slips all day!!!
 
seriously funny to read reactions to your build.[/QUOTE]

This build is for everyone who has been handed a free cam new in the original faded box with a tube of black lube to smear on it...now I just need to procure the rest of the parts.... I did see a single carb tunnel ram for sale local...
 
The only way you should buy a single four top tunnel ram is if there is a dualfour top still available for it. What brand of tunnel ram is it? There is no such thing as a good single four barrel tunnel ram nor will there ever be. The biggest reason a properly designed tunnel ram works so well is there are two separate plenums connected together with a carb barrel over top of each individual runner.
 
The only way you should buy a single four top tunnel ram is if there is a dualfour top still available for it. What brand of tunnel ram is it? There is no such thing as a good single four barrel tunnel ram nor will there ever be. The biggest reason a properly designed tunnel ram works so well is there are two separate plenums connected together with a carb barrel over top of each individual runner.
It was the only sbm intake I could find on kijiji today... Was looking for a strip dominator
 
2 seperate plenums over the 8 runners? Can you post a pic of that unicorn?
 
2 seperate plenums over the 8 runners? Can you post a pic of that unicorn?
Looks like a single plenum...not going to buy the tunnel ram...the free cam is causing enough controversy
 
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Iirc they are all single plenum designs spread over 8 bbls. Unless its an IR (individual runner) Weber setup.
I built a motor around a set of pistons.....imagine that!
Stroker 360/40x.....
 
Everybody saying it won't work on the street is wrong. Period. It WILL TOO WORK. It will work FINE........BUT you're going to need a MAN of a converter. Like 3800-4500. 4.30 gears at as minimum. 12.5 static compression. BLUEPRINTED, not "guessed". LOTSA carburetor and intake and WHOPPER JOHN HEADERS. It WILL work. But you are going to have to build the rest of the CAR accordingly. Lots of people run bigger on the street everyday and they run fine.

Now will it work with 8.5 compression, stock converter and 2.94 gears? Yeah. It'll run but it'll SUCK.
 
Don't know why you can't use that cam and use 12:1 or a bit more on pump gas.

Why not???
The guy who gave me the cam builds lots of engines said the same thing...build it with around 12:1 and it can be made run on pump...put 1/2 race gas in it for the track
 
Everybody saying it won't work on the street is wrong. Period. It WILL TOO WORK. It will work FINE........BUT you're going to need a MAN of a converter. Like 3800-4500. 4.30 gears at as minimum. 12.5 static compression. BLUEPRINTED, not "guessed". LOTSA carburetor and intake and WHOPPER JOHN HEADERS. It WILL work. But you are going to have to build the rest of the CAR accordingly. Lots of people run bigger on the street everyday and they run fine.

Now will it work with 8.5 compression, stock converter and 2.94 gears? Yeah. It'll run but it'll SUCK.

Now we are getting somewhere! I want to build starting with the cam and working back...
 
Now we are getting somewhere! I want to build starting with the cam and working back...

You'll get a lot of guys tellin you that's backwards thinking.....but it you ALREADY HAVE the cam, that's how you have to do it. The cam dictates the build. There's nothing wrong with that.
 
2 seperate plenums over the 8 runners? Can you post a pic of that unicorn?
LOLOL, good response to my askew view! Yes, technically they are single plenum, but most cast tunnel rams only have a relatively narrow passage connecting the two plenums. In these, there is more pressure equalization through the connection than any significant front to rear or rear to front flow reversal of mixture happening. So in an over simplification of this I stated dual plenums, because there is some separation of mixture flow of the front carburetor to cylinders 1,2,3, & 4 with the rear flowing most of the mixture being fed into 5,6,7, & 8 cylinders. Probably not so much in the bigger competition V bottom plenum cast or usually sheet metal pro stock type intakes. But, the positioning of the carb venturis above the top of each runner (albeit on top of the plenum) has some significance. Ever notice most tunnel rams will have a few or all the runners angled to do this? Same reason split Dominator type carbs were developed for use on the mountain motor builds.
 
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If I do use the 4 inch crank I have in a 340 block what heads should I look out for?...I just finished a 360 with EQ heads so I don’t want to go that route
 
As for the BB or SB 446........ it was 30 years ago........I don’t think anyone was building 446” SB mopars in 1990.
 
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