340 has no balls

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17remfan

17remfan

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Well ,been driving my numbers matching 69 340 dart around . Car doesnt have any balls to it . When i get on it , I seem to hear the pistons rattling .Ill try some better 110 leaded gas when I can and check timing but to me . I think Im looking toward a 455hp /408 crate engine . That should get things running the way i like .I dont want a slug on my hands.
 
it should be plenty strong,unless its overcammed,not enough converter,too high rear gear,or ignition timing off.Usually when an engine sparknocks,or pings,the timing is too high.My small blocks seem to really like less timing than other engines,and they pull real strong.My 318 is pretty strong,even with 276 rear gear,and stock lockup converter in a 904 tranny.Whats your cars combination,ie,engine,tranny,rear gear?
 
If the pistons are rattling around, it could be a number of things.

Poor octane
to much timing like burnt said or to quick timing
not dropping down in gear when it should.

Try to look into the engine first before dropping several grand on a create, by the way, you wouldn't get an argument from me on it's use.
The use of very high octane should not be needed.
 
17remfan said:
I think Im looking toward a 455hp /408 crate engine . That should get things running the way i like .I dont want a slug on my hands.
Click to expand...

Yea I'd go that route too :evil4:....I'll take that 340 off your hands....lol,just kidding....seroiusly,Ill buy it off you.........:toothy8:
 
A properly tuned stock 340 with a very good driver could hit the 13s back when the car was new. I think the article (from 1968 ) was posted on here long ago. They took a 68 340 Barracuda. Tuned it, put a pro drag racer behind the wheel.

I think you should look at your combo before getting a new engine.
 
340 with no balls..theres no such thing,something is wrong find out what it is,i'd rather have a stock 340 then a crate (crap) motor anyday...
 
Pistons sounding like they are rattling around and no power should be a good indication that you should stop driving it before you mess the block up if something like rods are an issue.
 
Put a little bigger cam in it and bleed off some cylinder pressure. That should get it to run reasonably well on pump gas and still have enough spark advance. That's assuming the rest of the engine is in good shape...

Mine ran like crap on 93 octane pump gas with all stock innards. Retarding the timing helped somewhat, but it was never right.

If you bail on the 340, I'm sure you'll have no trouble selling it.
 
fourspeed said:
Put a little bigger cam in it and bleed off some cylinder pressure. That should get it to run reasonably well on pump gas and still have enough spark advance. That's assuming the rest of the engine is in good shape...

Mine ran like crap on 93 octane pump gas with all stock innards. Retarding the timing helped somewhat, but it was never right.

If you bail on the 340, I'm sure you'll have no trouble selling it.
Click to expand...

First, is it a fresh motor?

What cam are you running?

Was it degreed in?

Pistons, forged or cast? Compression?

What is your total timing set at?

Take small steps looking into what the problem is, use a process of elimination, get the manual out and strat troubleshooting. Don't go chasing your problem with more parts. Start fro scratch and set a baseline and go from there.
 
My 340 had seen better days when I bought it(tired)So I got ahold of an older Mopar machinist(engine builder)and got him to do a little stroke(3.58)on the cheaper side.I,ve got X heads p and p,xe284h cam,performer rpm with holley 750 v.s.When dynoed I was shocked to see 452 hp!This is a 372 stroke,yes I could have went bigger,but I,ve seen 408,416 run similar hp #,s.Mine was 1/2 the price cause I already had the motor and heads.My 2 cents.
 
Thanks for all the in out here.I think I need to give you some info on my engine . Its the stock x head 340 that came with the car.The engine has 60k on it and doesnt smoke.

Its running the original stock exhaust manifolds and exhaust. Somone did put an Edelbrock LD4P intake on it which I hear has smaller ports than the heads. The carb is an older Edelbrock 750. The tranny is a 727 and in great condition. converter seem to be very stock and the rear is suregrip 3.55s

Someone placed a pertronics electronic in the dist to replace the point set up. The timing has NOT been check yet and I was very careful not to beat on the engine.

One thing, the engine does seem to get itself into 3rd gear right away . only take a few moments and its in 3rd. Its a column shift so im not doing much manual shifting . I will try manual shifting to see if they helps it from pinging .
 
This car seems to be hard to start like the gas has drained back from the line in the manual fuel pump .When I had the clear fuel filter I saw non full filter and thought about that .Once warmed up car seems to cruise ok infact I had it on the highway going 75 or so.it will take it but not all at once. Hard on the gas makes it rattle. Well, thats the story as I see it so far. I will be checking the timing . Its probably got too much .Is 5 degBTDC the correct setting ?? Oh and im not in a big hurry to yank that matching 340 from the dart . I know they are sweet. the 408 is an Idea but more of a last straw.im sure ill have more questions
 
I,d get another intake,check timing and also sounds like you need to set your kickdown properly(shifting to quick)Try your timing first,by the sounds of pinging,it needs adjusting.Good luck!
 
Around 10-12* is right for an SB. Also check your carb jetting/metering rods and the kickdown linkage for the transmission.
 
especially if the car is hard to re-start when warm, the timing is way too far advanced.

As for what the setting is, I never use a timing light so have never had any idea what my base timing is on my car. I'd pull a bit of timing out of it by loosening the clamp and turning the distributor clockwise just a small amount with the engine running. The you want to tighten the clamp and go for a drive. If the pinging has gone away, you're good to go....if it hasn't, pull a bit more. When I have a new car or combination, I drive around with a distributor wrench in the car and adjust it in parking lots.
 
Funny you say vacuum leak . I did buy the car to find one of the vac lines that function the heater controls to be unplugged and sucking air. I did plug that one but ill have to do more checking for vac leaks . kickdown lever adjust ,check . ill have to do that .Wish I had 5 or 6 of you here to look it all over lol.
 
Sounds like some work and a nice intake is in order.
 
The line for the heater control wont casuse that , i would look more towards carb base gasket , pcv port it would be a big one possibly intake to head leak look for sucking oil at the gasket{ spray wd 40 while it running listen for engine to speed up} also check the timing chain play with the dist rotor rotate the crank pully by hand clockwise, counter clock wise watch the rotor ..more than a few degrees and the chain is toast possibly jumped a few degrees what is cold cranking pressure ? stock camshaft? like was said a big cam can do same thing
 
I would get that Eddy carb off of it. I had the same hard to start problem with my 340. The carb was letting all the fuel drain back. Also found my distributor advance loose in the distributor letting the timing bounce around. Just my 2 cents.
Matt
 
hey the ld340 intake is one of the best you can run keep it or seel it to me LOL kidding....stop driving the car immediatly or detination will cause exsessive heat the piston failure ....do you know the iital timing / final timing?

what carb is on the car?

many factors in a drive train setup you have a lt of advice be careful the 340 motor is in my opinion better than the new crate 360's
 
Intake is not the LD340.. Its LD4B ,My error. Oh, Cam should be stock as far as I know . Doesnt look like anyone threw money at this engine ... Guys give me a good intake /carb sugestion. Would an Edelbrock performer RPM with a Holley 650dp/ 740? be ok ? You guys are great :cheers:


oh here is another clue/simptom.When I went to adjust the air bleed screws to smooth out each side of the engine , turning the screws in didnt seem to get a responce/rough like it should have. I was trying to turn them in then back out to get smoothest idle . didnt use a vac gauge though .
 
Just get the performer RPM..... But still, it shoudn't be a dog with the LD4B......

I find it hard to believe an Edelbrock can let all the gas drain back out, considering the inlet is on the highest part of the float bowls.... Your not parking it sideways, are you?
 
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