Cam and carb suggestions

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batoven

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Greetings,

It's been awhile since I've posted but I'll get to the nitty-gritty. I'm looking for cam and carb suggestion for my build. Here it is:

1971 Dart Swinger 2 door, was a Slanty, now has a '71 340.

What I've done so far:

Early "71 340 block .030 over and decked to flatten it (.005)
Stock floating rods relieved, 'peened, and resized with new ARP fasteners and pin bushings
Mains have ARP bolts with line-hone to true-up crank saddle
Stock forged crank, turned 10/10 and balanced
Pistons- SRP Flat-tops- 9.7 cr (maybe a bit higher due to the block/head surfacing with the thin gaskets used..see below).
Stock early "J" heads - 2.02 and 1.60 valves - 3 angle valve job - mild pocket porting, intake and exhaust runner clean-up and gasket match on exhaust and intake sides and surfaced .005
Crane adjustable rockers and shafts (1.5 ratio)
.028 thin head gaskets
LD 340 intake
Stock HP 340 exhaust manifolds (yes..I'm one of the "header haters").
Stock 904 auto with 2600 rpm stall (B&M converter)
Mopar electronic distributor P 3690430 with ECU P4120534
8 3/4 rear with 3.54 Sure-Grip
Rear tires - BFG radials P235/60 R15 98S

Not a daily driver, but a Weekend Warrior- maybe ONE or TWO passes at the track to see what it will do.

What I want - Panty dropper.
To launch like a bullet from a stop light with that high-revving, screaming small-block sound.. with some wheel-spin but a hard hook up shortly thereafter.

I need a cam and carb combo suggestion to make it happen...
 
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Rumble...won't stock exhaust ( even though they're the HP 340's) kill me on the lower end with the that cam?? Solid or Hyd doesn't matter to me...should'a wrote that too.
 
My man, you asked for advice on a cam that will do .... add your description....

You gave specs and very importantly, the rates stall of the converter. Coupled with gears and tire size.

Your exhaust manifolds are crippling everything you do going past 1 step above stock specs for a cam. So your going to suffer no matter what you do unless it is a tiny cam.

If you want a cam that works with stock exhaust manifolds, go back to a stock cam. The OE 340 is a very good one.

The other thing about cams you don’t know about (or otherwise you would not have asked what you did)
Is cams have operating rpm bands. In that area, they work best. With the Avilable specs of your build and the mentioning of it NOT being a daily driver but a weekend warrior, that’s the cam I myself would use given YOUR parameters.m
You wanted a suggestion, there ya go. Hate me if ya want, but that’s what I would use. It fits your stall converter and gear and tire set up and being it is a solid tappet cam, it’ll scream rpm for you.
If you have a well matched converter (or more accurately an actual good converter, your not going to have issues.

Now you had a stock stall, I’d recommend a cam of a max of 204@050 on the intake.
 
I have the old 508 purple shaft in mine, but it will NEED a converter and a little gear and springs, but a 7000 rpm "panty dropper" as you put it!
 
Rumble,

I've followed you awhile on this site..and I know you know what your talking about. I merely asked if that cam was a bit overkill for the stock HP exhaust mannys. I know they are going to be my Achilles Heel. And assuming people don't know about cams because they're asking a question on a forum is a bit presumptuous...but thanks for your input.
 
Hey man, I’m sorry. But that’s my choice and my answer was I’ll geared for you but more general public that doesn’t know.

My bad, again, I’m sorry.
 
batoven said:
And assuming people don't know about cams because they're asking a question on a forum is a bit presumptuous...but thanks for your input.
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I’d like to add that, NO, not IMO. Not at all. A lot depends on how the question is asked (perceived)
Presumptuous is not how I felt, wanted to come off as of convey that I’ll will your way.

I could have given and answer of , this cam, it’ll rock, and a resounding “yes” to the other question without explanation.

Then you know what I get as a response, “Geezzz, you could be a little more help.

Bottom line without getting into detail, I post a lot, not every reply is sweet pie, I cannot please everyone via text.

A little assumption is a basic must.

But again, my bad, I’m sorry.
 
rumblefish360 said:
Hey man, I’m sorry. But that’s my choice and my answer was I’ll geared for you but more general public that doesn’t know.

My bad, again, I’m sorry.
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No worries...just trying to get the most bang for my hard-earned bucks. And With retirement approaching, I want to catch up on those languishing projects while the good money is flowing in!
 
So I'm pretty much stuck with the gears...but the converter can come or go. Given everything but the converter...what stall would you go with?
 
Once you figure out the cam, call Dynamic.

Retirement coming quick for me as well.
 
batoven said:
So I'm pretty much stuck with the gears...but the converter can come or go. Given everything but the converter...what stall would you go with?
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This cam comes on very hard at 3000 rpm. If its a short trip car, 3k converter, otherwise a 2600 or so would be ok. There are much more modern grinds/cams, but this is a very hot cam that works with stock heads. You better be right about your comp. ratio, this cam will kill a 8.0 to 1 engine.
 
I've heard of this cam:

.444/.456 lift - 276/284 duration - 52 degrees overlap - 112 degree centerline

Supposedly an old Mopar grind...maybe even a specific 340 auto grind?.. Not sure. The lift looks ok ..but wouldn't mind seeing a 484/495 with that duration ....but maybe with a 108 centerline or 110 max for my 2600 stall and 3.54 gears? What say yee?
I'm close enough to a custom cam grinder as I know that would be a one-off grind.
 
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my cam from bullet is being sent tomorrow, maybe fill out their recommendation form and see what they say
 
mechanicmark said:
This cam comes on very hard at 3000 rpm. If its a short trip car, 3k converter, otherwise a 2600 or so would be ok. There are much more modern grinds/cams, but this is a very hot cam that works with stock heads. You better be right about your comp. ratio, this cam will kill a 8.0 to 1 engine.
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This is a 108* c/l cam with 292* advertised duration[ like 248* at .050" i recall] It doesn't have much vacuum at all.
 
I should clarify that I DO NOT have power brakes...only power steering..and want to keep that at a minimum lol!
 
The stock 340 cam will do all that you want.......except the panty dropping thing. That part is up to you.
 
Lighten up, Rumble. You've answered personal questions of mine, and it was all good. We all appreciate your experience and input. Nobody bats a thousand. Keep plugging away for the benefit of us in the silent majority.
 
My choice would be along the lines of what Rumble suggested.

Not “exactly” that....... but similar.

However, that cam he suggested would probably be better(make more power in that combo) than what else I’ve seen suggested so far.
 
In the wife’s ‘67 Cuda, 360/904-2600 stalled - (work done by Pro Torque, down the street from me) 3.55/26 inch tire, I have a Comp Hyd. roller @ 224 @050 intake with Edelbrock heads and TTI exhaust.

She wanted a driver with some power. So I started here. This drives like a normal car. With in incoming ProMaxx heads and proper springs for the cam, this should make much better power over the Stone stock Edelbrock heads until about 6K.

Sorry, no time slip. It’s also not a 1/4 mile car or set up as so. Just a driver.

472EF139-561C-46E7-B8A3-3A38FD8E622D.jpeg
 
batoven said:
Pistons- SRP Flat-tops- 9.7 cr (maybe a bit higher due to the block/head surfacing with the thin gaskets used..see below).
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My opinion is not to guess. CC the heads. Can't tell you how much I regret not doing this.
mderoy340 said:
Stock j heads will only handle around .500 lift max
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This^^^^
Without flowing the heads this is a good rule of thumb.
 
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