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View Full Version : Mopar Newbie, Please Help


MoparMan
11-14-2007, 02:00 PM
Hi there, I'm new here.

I know basically nothing about engines and have some dumb questions to ask that I really would like a simple answer too.

After looking up Dodge Challengers, Darts and Chargers on youtube, I have gathered some basic questions.

Is there some engines that you need to keep your foot on the gas or else it will shut off. I was watching a video of a yellow Dart that someone thought was stalled, and the uploader replied with something along the lines of "no you need to keep supplying gas or it'll shut off".

Why do some engines keep a certain rhythm and some just randomly bubble, even though they are both the same number (e.g. 440's). I really don't understand this. I have some examples here. This is a 440 idling:

http://www.youtube.com/watch?v=krQmfaXRZH8

As you can hear it is pretty well random patterns that the engine makes.

This is another 440, and yet it appears to have a rhythm to the engine

http://www.youtube.com/watch?v=FqA1MGJvM6E

Basically to recap, why does the same engine have different noises and stuff. Thanks for the welcome in advance.

DHARROD
11-14-2007, 02:20 PM
My quick answer is Cam, Crank and compresion ratio. Sounds like your seeing engines that are creating 'old shool' horsepower/torque - have a lot of 'space' for fuel, longer distance for the piston to travel to create power/torque, thus they can't be starved for fuel (can lead to larger carb and psi). At a low idle you'll hear the firing order more distinctly (slow heart beat) - give it fuel and the beast is alive (fast heart beat one on top of each other). An engine guro will jump in on this and give you more clarity. Often these cars have to have a higher RPM at idle to keep the heart beat sounding adequate.

camcojb
11-14-2007, 04:16 PM
the first clip is just flat out idling too low; that would drive me nuts, not a good sounding idle in my opinion. I had a friend in high school that had a tunnel ram on a stock 383 Road Runner, so he idled it like that guy to make it sound like it had a bigger camshaft in it.

As above, the camshaft affects the idle quality and speed. There is no reason to have to keep your foot on the gas to prevent the engine from stalling however, no matter the cam involved. That's just poor tuning or poor combo of parts.

Jody

MoparMan
11-15-2007, 11:22 AM
Thank you very much for the help guys:hail: .

This is a nice forum, I asked this on a Mopar forum and the guys on there just told me to take a hike for such a dumb question.

camcojb, exact same opinion. I don't like it sounding as if its on its last legs, that second video is a lot nicer.

So technically all these engines can make the same sound, its just that combination of parts that affect it.

Thanks for the kind replies and have a nice evening (or whatever time it is there).