340 No low end power

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I had nothing but issues with my unilite. Get a good MSD if you can afford it, get a 6 or 6al box, I've had real good luck with my weiand stealth intake and a good 650 carb and you should be good. Definitely find out your gearing and stall then go from there.
 
My 2bbl 273 can do a brake torque, how is it when just hammer without doing a brake torque? Does seem like its got a stock converter?
 
I fought this issue with my Cuda and I knew (or thought I knew) everything about the car. My 340 ran great at full throttle, but had no low end and poor vacuum and idle. Found a very leaky intake. Older Edelbrock manifolds may not be properly machined leaving a gap at the bottom of the intake. Symtoms: low vacuum, poor idle, inability to set A/F ratio, idle screws out excessively (4 turns or more), no sensitivity to tuning.. This resulted in burnt valves and further loss of power.
I started with a compression test which showed low cylinder pressure in #7. A leak down test (using a home built gauge set) showed other problems in other cylinders. Took heads off and replaced manifold with Air Gap. Idle problem solved, and picked up 1.2 seconds at Brandimere.
So, check everything. Know your advance curve and set points. Verify the cam instillation via centerline measurement against cam specs. Know the stall speed of the converter, gear ratio, tire size. Use on-line programs to correlate ET and MPH with HP. Compare your results to best theoretical and look for reasons why your car may not be performing.
Engines are not mysterious. There is always a reason why things happen. It just may be a pain to find the root cause, but it is there.
Best of luck,
Bob
 
Try the ignition tune up first, it's cheap and requires little in parts, cost. Maybe a set of lighter springs. The mechanical advance limit can be adjusted with a drill index so you don't need the keys they sell.
 
Like mentioned already, poor combo.

The torker II works decent with a high stall converter. Stock converter is about the worst converter to match that manifold. IMHO that is why most people say the manifold is a POS because they run a stock converter and/or put it in a heavy vehicle. Saw a guy on the web that had one in his 4x4 ramcharger and was saying it was a heap of crap. :banghead: And yes its poorly named.

I think the cheapest/easiest option is to just throw a better suited manifold and carb on it. LD340 or air gap would work great.
 
Bought a 70 swinger that was the same way. Had a .484 purple shaft cam that was installed @ 112. Redegreed the cam to 108 and it was a new engine.
 
or a simple as a vacuum leak id start there make sure the carb is sealed and the intake is sealing then go to cap, plugs, wires arching , not yet, timing like cracked back said might be simple as tune up no = then start tear down
 
Snow is going to fly this weekend so looks like I will have plenty garage time to keep myself busy. Thanks for all the great input. I will report back with results and I'm sure more questions.
 
Before you change anything: have you verified that the engine is, in fact a 340?
Have you done a compression check? Once you have verified the condition of the engine, you can proceed.
The phrases "fresh rebuild" and "built to six-pack specs" don't mean anything.
Come to think of it, I've seen several engines built to 6-pack and even 12-pack specs, those being 6-packs of Bud or Coors. They didn't run very well.
 
Yeah calling for snow up in Cache Valley too. Beautiful Dart by the way. I hope you get it sorted out. What part of Utah?
 
AdamR said:
Loose the intake. Is the carb an aftermarket carter or an old factory avs ? I would swap the car for a new Edelbrock AVS 650 so you can get tuning parts easier.

The unilite will probably burn out at some point and when it does replacement parts are almost as much as a new distributor. but for now you need to find your total timing also. You may have 13 initial and to much total.

How much vacuum does it have at idle ? is the idle rough or smooth and what rpm does it idle at. Im betting its got a 284-.484" Purple shaft in it which is why it doesnt feel very torque. That cam and 3.21 gears with a stock converter is going to feel like a slug.

Pull the cover off the rear and see what the ring gear is stamped with. Im betting 2.76 or 3.21s
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just a note, if the rear end is indeed a suregrip, you don't have to pull the cover to find out what gear set u have. jack up the rearend and in neutral turn the tire one full turn and watch how many times the driveshaft turns...if it turns 3 1/2 times to one tire rotation that means you probably have a 3:55 gear, if it turns almost 3 times you probably have a 2:96, little over 4, probably a 4:11 etc. etc.

also, i live in colorado and have a torker manifold on a 360 with a 600cfm carter with a 509 cam 292 dur. 360 heads w/slight port and 202 valves also shaved .038 thousands.. stock bottom end, 3200 stall converter full advance at 36 degrees.....i beleive initial is somewhere around 15 or 16 degrees...manual valve body race prepped 904....... it used to have a 3:23 gear in it......hammer down from a dead stop it would light the tires up so hard i would have to get out of it to keep it from over-revving.........you sure you got what u paid for?? did the guy show u receipts\pics of the build? does it indeed have the stamp "340" on the front of block just below the drivers side or left head? i don't know guys.....lot of information here, but if i was to take an uneducated guess i would say that it is a timing advancement problem, or carburation........if it's everything that you've been told that it is.......it should go to full advance in a matter of a split second, if it's not.......well lets just say lag city. time to start testing/verifying parts and settings, just my 2 cents...good luck,
higgs
 
Like every one has said, Get ride of that POS manifold!

My sons 73 power wagon had that same manifold. Bolted on a stock duel plane manifold and his mileage Jump and he can brake the tire loose on pavement!
before you would have to go light on the throttle, tell about 15 mph and then stab the throttle.

Nothing was changed but the manifold. Could NOT be leave the difference!!!!!!

Dist tuning is the best place to start.

I also live at high altitude.
My 340 had 24* at idle and total at 38. works pretty good for me.
 
id look at the timing first like others have stated.it sounds like it could use alot more initial.the 3" exhaust wont hurt low end as much as you think,and there are better intakes,but something else is the culprit i think.for example i live at 4200ft and the 340 in my dart wears a tunnel ram and 3" exhaust......however it spins em at a light stab.
 
Badart, south end of the valley, Herriman. If I can't figure it out Ill have you up for dinner and see if we can fix it! :)
It is a 340, Double checked checked tonight, got me worried! Not sure on the rear end, no cover, looks like you drop the drive line and pull it out the front? Tried wheel/drive line trick and it driveline turns only 1.5 times, wheel once? Neutral or in gear? Used a can of carb cleaner, no vacuum leaks anywhere. Will check timing this weekend.
 
dgibby said:
Badart, south end of the valley, Herriman. If I can't figure it out Ill have you up for dinner and see if we can fix it! :)
It is a 340, Double checked checked tonight, got me worried! Not sure on the rear end, no cover, looks like you drop the drive line and pull it out the front? Tried wheel/drive line trick and it driveline turns only 1.5 times, wheel once? Neutral or in gear? Used a can of carb cleaner, no vacuum leaks anywhere. Will check timing this weekend.
Click to expand...

Next time that I am in that I am in that part of the valley I may take you up on it. Sounds like you have and 8 3/4 in it. How many rpm are you turning at 60 mph? Like these other guys have suggested, I would start with the timing and go from there. Crackedback knows his stuff and he is right altitude likes timing.
 
dgibby said:
Badart, south end of the valley, Herriman. If I can't figure it out Ill have you up for dinner and see if we can fix it! :)
It is a 340, Double checked checked tonight, got me worried! Not sure on the rear end, no cover, looks like you drop the drive line and pull it out the front? Tried wheel/drive line trick and it driveline turns only 1.5 times, wheel once? Neutral or in gear? Used a can of carb cleaner, no vacuum leaks anywhere. Will check timing this weekend.
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lots of help here, the wheel driveline trick works only w/a suregrip, when u turn the wheel, the wheel on the other side should turn in the same direction, if it turns the other way u have an open rearend, and it would be hard to determine your gearing. like the guys said, sounds like an 8 3/4 axle....open rearend.......
higgs
 
Yeah, mess with it last night. Only the pass. rear tire seems to be the drive wheel... makes it even more pathetic that they wont break loose.
Someone asked if I really know what I bought.. Not really. As my wife says, I had a lapse in judgement when I bought it. Never been around Mopars, never owned a hotrod. Been in the tire business my whole life but am a little limited on some of my diag skills. Bought the car for 2700.00 bucks thinking it would be hard to get hurt on. Yes it does have what I confirmed, mainifold,carb, cam,trans etc.. some of the other was based on what I was told whick I know is b/s most the time. Figure I could put a few bucks into it and learn as I go and hopefully come out with a cool driver. thanks for all the input, I'll let you know how it works out.
 
I dont think you got a bad deal at all. It just needs some sorting out,
 
yeah, came with all of it and then some. They guy had been collecting misc. parts for almost 10 years when he ran into $$ issues and sold it. I put a top on it, interior, wheels and the basic repairs. Been selling the extra parts to pay as I go. I agree, it's strong, just needs to be fine tuned.
 
My own feelings - like Cracked said - find out what cam's in it - you can get a good lead just by removing the valve cover and rockers from one side, and using a dial indicator on the edge of one of the lifters. Dio a compression test first, then pull the cover off... Once you know those two things post them and we can go from there. MP cams are easy to install way of which would give the symptoms you have. It may not be parts changing, but simple blueprinting that fixes it.
 
Just an example,, We put kick-*** 360 in a customers LeBaron, had a 3:55 gearset to replace his 2:76's,...
Against me better judgement, he talked me into letting him have the car for the weekend to break-in the engine, before we put in the gears..

I warned him it would be a dog off the line, (didn't know he had a steep driveway)

He phoned me about 20 mins later, telling me the motor was f@#$ had no power,, couldnt even pull UP his driveway,.

I took all the abuse, and sent our wrecker out to get the car,,
I asked him to come down in the morning, and watch us change the gearset... nothing else,,

After install and test drive,, car smoked the tires, rubber into 2 nd..

He was blown away,, and very apologetic,,

Very satisfied customer for years after..

Cam vs gearset.. my .02
 
How's it idle does it sound really lumpy? and if it's an open diff it's probably highway gears, but do like the others said start with setting up timing and carb, do a compression test also cause if you got a lot of cam and low CR a cam swap maybe in your future, start with gears and intake RPM, than depends what got cam and converter.
 
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