340 Build Final Combo. What Do You Think?

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I don't know anyone else's experience but I used an aluminum flywheel one time and hated it. There was no inertia for letting off the clutch and I didn't like it for the street at all. I found myself burning the clutch more to get going and hole shots was much different. It was a 440 with plenty of power. Starting off in gear was terrible. Just a thought. I am sure the others have thoughts to share. Good luck. Great motor!
 
I don't know anyone else's experience but I used an aluminum flywheel one time and hated it. There was no inertia for letting off the clutch and I didn't like it for the street at all. I found myself burning the clutch more to get going and hole shots was much different. It was a 440 with plenty of power. Starting off in gear was terrible. Just a thought. I am sure the others have thoughts to share. Good luck. Great motor!


I never use anything but aluminum. If you have a 2.20 first gear (Chrysler never made a box with that first gear ratio but IIRC the M21 or M22 Muncie had something like that worthless first gear so I’m using that as an example) and a 3.08 axle ratio it may not like an aluminum flywheel.

And if the car is 4500 ponds and geared like that it would suck.
 
View attachment 1715559263 So after sleepless nights and pacing at work I have finally decided on my 340 combo. I’ve looked at almost every camshaft available off the shelf, made some calls for a custom grind but finally decided to go to my special place (my bench covered in cams) I decided on this obscure voodoo cam deciding to save the 250 and put it elsewhere. (pictures for specs) here is the combo.

Short block came from a parts car-
Speed pro heavy .030 flat top. .020 out.
Stock rods with aftermarket bolts.
Forged stock stroke crank. Windage tray and fab pan.
10.1:1 static
8.1 dynamic


Top End-
J heads 2.08 valves some mild porting (see my earlier post in the week for port pics)
Air gap or tunnel ram haven’t decided.
Holley 750 double pumper (not for tunnel ram)

Exhaust- 1 3/4 long tubes into 3in X-pipe dumped at axles.

Accessories- alternator and water pump
(Electric fans)

Extra info (chassis)-
Car is 2900# without driver.
4 speed (2.66 first)
4.10 8.75
Aluminum flywheel
Aluminum DS
McLeod clutch( yes I know)

Let me know what you think. I’m ready to get flamed.

Empty your inbox please. J.Rob
 
i'm not convinced that cam is a good match for the J heads.For a daily driver i'd opt for the rpm and ditch the air gap.Drop down to 2 1/2" exhaust and 1 5/8" headers.No H or X and 650 Thunder Edelbrock
...is 10:1 estimated?
 
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i'm not convinced that cam is a good match for the J heads.For a daily driver i'd opt for the rpm and ditch the air gap.Drop down to 2 1/2" exhaust and 1 5/8" headers.No H or X and 650 Thunder Edelbrock
...is 10:1 estimated?
You almost had me for a second... I almost thought you were serious until I saw no x or h :rofl:
I’m surprised you didn’t go with a thermoquad lol.
No it’s calculated along with my dynamic.
 
You’re still on this? Well ask any member to read what you typed and ask them if they think that means you’ll have no problems. You phrased it poorly and I whined about it and now you continue the whining. Go take a nap and change your diaper as I have already done so.
I took it the way RRR posted
 
I also took the way that it was posted. No way that you would ever have enough valve clearance. My understanding.
Sometimes-----------------------------------
 
OK..stock heads stall out at about .480 lift and that's why i questioned the cam. I thought i read daily driver and your other choices seem to favour a quarter mile piece.
 
OK..stock heads stall out at about .480 lift and that's why i questioned the cam. I thought i read daily driver and your other choices seem to favour a quarter mile piece.
I’m really don’t mind suffering a bit to be as max effort as I can when it comes to a daily. In my opinion a bigger cam doesn’t change drivability it just changes the rpm range at which you do so. From what I’ve seen from the stock port heads, you are absolutely right. But I’m hoping with this port work it will allow the flow to average in higher lifts (not necessarily gain) so I’d be okay. The cam is being run because it’s what I have even though I need better heads. (Would really like a set of LAX heads)
 
Here is what I MEANT to say. My bad. I'm old and I was tired.

"I don't think that combo has a snowball's chance in hell of piston to valve INTERFERENCE"

But again, nothing smartass was EVER meant or implied.
 
Here is what I MEANT to say. My bad. I'm old and I was tired.

"I don't think that combo has a snowball's chance in hell of piston to valve INTERFERENCE"

But again, nothing smartass was EVER meant or implied.
It’s over with. No hard feelings just let it go.
 
I know I know I’m just being a baby. Sorry Rusty. Hopefully it will be strong. I’m hoping for 110mph I’ll be happy with more though.
you should be able to do that , i had a 340 similar build but automatic ran a best of 13.1 at 106 mph , but i'm not much of a drag racer and traction was a problem . you should do better
 
you should be able to do that , i had a 340 similar build but automatic ran a best of 13.1 at 106 mph , but i'm not much of a drag racer and traction was a problem . you should do better
It should be around there
I’m hoping to get the whole car together in the next couple weeks. Hopefully it goes that quick lol.
 
That’s what I was hoping. What’s your combo?
67 Dart - 340 .040 Speed Pro flat tops .020 above 10.3:1, 4bbl 750dp, Airgap, Comp SFT XS274S 236@.050 cam .500 lift, 63cc IMM indy LA X iron heads, TTI headers, low gear set 904/gvod, Turbo Action 10" 3200 converter 4.10, 3200 lbs. Best so far 11.77@113.7
 
67 Dart - 340 .040 Speed Pro flat tops .020 above 10.3:1, 4bbl 750dp, Airgap, Comp SFT XS274S 236@.050 cam .500 lift, 63cc IMM indy LA X iron heads, TTI headers, low gear set 904/gvod, Turbo Action 10" 3200 converter 4.10, 3200 lbs. Best so far 11.77@113.7
How in the hell could I possibly buy those heads from you? Lol kidding. Kinda. I’ve been looking for a set of IMM LAX heads.
 
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