340 more pop

[rm69dart]

Hello,
After my health and now my early retirement. Want to add a little more pop in my 340 it's 40 over and has j heads, an ld340 intake with a 750 holley double pumper. Bottom end is fairly normal, mopar electronic ignition. A904 trans and mild shift kit, rear is 355s. Looking for more aggressive idle and little bit more pop of the line. Suggestions on cam, want to stay with hydraulic lifters. Is there a kit of a cam, springs part numbers would help. Just want to stay with top end work for now. Thanks

 

[SpeedThrills]

I don't have an answer for you, but others will probably want to know if you have headers, and what exhaust system in general.

 

[rm69dart]

I don't have an answer for you, but others will probably want to know if you have headers, and what exhaust system in general.

Yes forgot about exhaust have dougs headers and 2.5 magna flow exhaust. Thank you

 

[MOPAROFFICIAL]

Step up in cam size and buy a higher stall convertor.. or go steeper on the gears..like 3.73 or 3.91

 

[69FBCuda]

Cam?

 

[RustyRatRod]

We'll need to know the static compression ratio in order to give accurate recommendations, otherwise we're shootin in the dark.

 

[rm69dart]

Hello, when I had the engine rebuilt the guy said he put a 340 cam it idols steady and dwell is at 12 degrees

 

[MOPAROFFICIAL]

We'll need to know the static compression ratio in order to give accurate recommendations, otherwise we're shootin in the dark.

Gloryhole style cam selection lol

 

[Workingdog1]

Hello,
After my health and now my early retirement. Want to add a little more pop in my 340 it's 40 over and has j heads, an ld340 intake with a 750 holley double pumper. Bottom end is fairly normal, mopar electronic ignition. A904 trans and mild shift kit, rear is 355s. Looking for more aggressive idle and little bit more pop of the line. Suggestions on cam, want to stay with hydraulic lifters. Is there a kit of a cam, springs part numbers would help. Just want to stay with top end work for now. Thanks

I'm with the #4 opinion and in similar situation. The 340 in 64 Dart is stout enough but no headers yet.
The setup is crying for a converter and minimum of 3.73's. I might be happier going 3.91 or 4.10 for my use as just something to go burn tires on way to town by the cemetery.

As a teen my 69 340 Dart 4 speed needed $$$$ and to get running swapped a 727 and stock stall converter as all I could afford.
That car needed a stall and much deeper gears than the 3.23's.

Keep us posted on your progress.
Jeff

 

[MOPAROFFICIAL]

Lose the points and get an electronic ignition for starters.

Hello, when I had the engine rebuilt the guy said he put a 340 cam it idols steady and dwell is at 12 degrees

 

[RustyRatRod]

Gloryhole style cam selection lol

 

[MOPAROFFICIAL]

Could probably tune the off the line without a cam change and be happy IF you can go without the lumpy idle part

 

[RustyRatRod]

Hello, when I had the engine rebuilt the guy said he put a 340 cam it idols steady and dwell is at 12 degrees

That's one problem right there. Dwell setting for a 340 is 28-32 degrees.

 

[Bewy]

OP says it has Mopar elec ign. He said dwell is 12* but I think he meant initial timing is 12*.

 

[RustyRatRod]

OP says it has Mopar elec ign. He said dwell is 12* but I think he meant initial timing is 12*.

Could be!

 

[cookietruck]

OP says it has Mopar elec ign. He said dwell is 12* but I think he meant initial timing is 12*.

Or vacuum is 12” at idle?!
Prob makes sense for a factory 340 cam

 

[cookietruck]

Hello,
After my health and now my early retirement. Want to add a little more pop in my 340 it's 40 over and has j heads, an ld340 intake with a 750 holley double pumper. Bottom end is fairly normal, mopar electronic ignition. A904 trans and mild shift kit, rear is 355s. Looking for more aggressive idle and little bit more pop of the line. Suggestions on cam, want to stay with hydraulic lifters. Is there a kit of a cam, springs part numbers would help. Just want to stay with top end work for now. Thanks

Whats your budget?
Does it run hard once you get into the powerband?
Maybe as simple as a good converter?

Or step up the cam, better heads and still need a good torque converter.

 

[RustyRatRod]

Or vacuum is 12” at idle?!
Prob makes sense for a factory 340 cam

Who knows? People expect a thesaurus of answers while giving a sticky note of information.

 

[junkyardhero]

more pop off the line? stall and gears.

sound lumpy at idle? pull some timing out and take a few turns on the carb screws.

in all seriousness, it *really* depends how much compression you have. if it's reasonable, a step or two on the cam plus a stall converter will likely yield the results you're after.


there's a lot of different ways to approach this and accomplish a suitable end result. it just depends on how you're going to use the car and what kind of budget you've got-- and if you're doing the work, what you're comfortable with tackling.

 

[Illahe]

We'll need to know the static compression ratio in order to give accurate recommendations, otherwise we're shootin in the dark.

If its got 9.5:1 or more an Isky Mega 280 will chug.