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Started new engine!

Well I found out I forgot to hook up the electric choke, I did that and got it to idle, brought it up to operating temperature and shut her down. That's what the engine builder told me to do because its a full roller cam. He said to wait until it cools and ten do it again. After I do that I will get the timing down, at least I got it running!
 
New motor break-in's require to at least buzz the motor at about 2500 rpm's for 20 min's or so. Hope you didn't hurt anything if you didn't??
When you do fire it again, play this game please, buzz it up in park!!!! You don't need to hurt anything more then you may have, if you haven't. I sure hope not? Others will give me a sticky on this!!!!
Good Luck
 
69a100 said:
New motor break-in's require to at least buzz the motor at about 2500 rpm's for 20 min's or so. Hope you didn't hurt anything if you didn't??
When you do fire it again, play this game please, buzz it up in park!!!! You don't need to hurt anything more then you may have, if you haven't. I sure hope not? Others will give me a sticky on this!!!!
Good Luck
Click to expand...

I believe op said he has a roller cam.
 
69a100 said:
New motor break-in's require to at least buzz the motor at about 2500 rpm's for 20 min's or so. Hope you didn't hurt anything if you didn't??
When you do fire it again, play this game please, buzz it up in park!!!! You don't need to hurt anything more then you may have, if you haven't. I sure hope not? Others will give me a sticky on this!!!!
Good Luck
Click to expand...

Its a roller cam, the break-in is a little different. The engine builder said you didn't have to do the 20 minute thing. I'm going to go by what he told me to do.
 
Well, I got her idling pretty good today. I did the timing at 18 degrees and it idled good. When I press the pedal it backfires through the carb. I haven't had a chance to do total timing because it was only me, I need to get one of my friends over here so I c do that. Any ideas on backfiring through the carb? Should I advance it more?

I tried to upload a video idling but its too big, it sounds good though!
 
So you're saying the carb is fresh off a Dyno engine that matches your engine to a tee?
..Or theres a shitload of carb tuning to do..
Whats the history on the carb
 
If the timing, ignition is ok next step is the carb.
What type/model is it ?
Is it new or from another engine ?
What happens if you gradually bring the rpm's up ?
Still back fires or not ?
 
RemCharger said:
So you're saying the carb is fresh off a Dyno engine that matches your engine to a tee?
..Or theres a shitload of carb tuning to do..
Whats the history on the carb
Click to expand...

No Not saying that, it wasn't dynode. I have a street demon 750, its supposed to be ready right out of the box. When I researched it, got great reviews for running out of the box. I'm not a carb person so I wanted the easiest option. Maybe it needs tuning?
 
MoparLeo said:
If the timing, ignition is ok next step is the carb.
What type/model is it ?
Is it new or from another engine ?
What happens if you gradually bring the rpm's up ?
Still back fires or not ?
Click to expand...

Street demon 750, new carb, whole new engine.
When I bring up the rpm's it will backfire.
 
mpro69rr said:
No Not saying that, it wasn't dynode. I have a street demon 750, its supposed to be ready right out of the box. When I researched it, got great reviews for running out of the box.
Click to expand...
They all state they will run out of the box. They will run, but by no means be tuned to your engine. One of the best investments I made was an A/F gauge. That and a vac gauge ran into the cabin makes carb tuning a whole lot easier.
 
I wouldnt go running down the carb path yet. No offense, but I'm not confident in your assessment that it's backfiring. Are flames coming out the carb? Would like to see a video of what you're describing. Generally carbs are not that bad out of the box unless its a complete mismatch, or there is something wrong with it. A new carb shouldnt be causing it to backfire. But then again, anything is possible, just would not start with that presumption.

What are the cam specs?
What is the compression ratio?
What is the cranking pressure?
What is your idle rpm?
Is it rock steady?
Idle vacuum?
Carb fuel level?
Idle/neutral fuel pressure?
Look at, and maybe change the plugs

I would want this information before touching the carb
 
mpro69rr said:
No Not saying that, it wasn't dynode. I have a street demon 750, its supposed to be ready right out of the box. When I researched it, got great reviews for running out of the box. I'm not a carb person so I wanted the easiest option. Maybe it needs tuning?
Click to expand...
Never had luck with Demon, sold it and went to Quick fuel.
 
BSB67 said:
I wouldnt go running down the carb path yet. No offense, but I'm not confident in your assessment that it's backfiring. Are flames coming out the carb? Would like to see a video of what you're describing. Generally carbs are not that bad out of the box unless its a complete mismatch, or there is something wrong with it. A new carb shouldnt be causing it to backfire. But then again, anything is possible, just would not start with that presumption.

What are the cam specs?
What is the compression ratio?
What is the cranking pressure?
What is your idle rpm?
Is it rock steady?
Idle vacuum?
Carb fuel level?
Idle/neutral fuel pressure?
Look at, and maybe change the plugs

I would want this information before touching the carb
Click to expand...

I would say it was backfiring, I saw fire and at one point I had to turn the engine over to get rid of it.

What are the cam specs? Not sure, I would have to look at the builders paper work
What is the compression ratio? I think its 10:1
What is the cranking pressure? Not sure
What is your idle rpm? Not sure, didn't have my tach set up
Is it rock steady? Idle is steady
Idle vacuum? I would have to check, I do have a vacuum gauge.
Carb fuel level? Not sure how to check
Idle/neutral fuel pressure? Not sure how to check
Look at, and maybe change the plugs - I will do this

The carb got high reviews for running out of the box, a lot people said they didn't have problems with it and didn't need to tune it. Although I'm not sure if any of those people had mopars. I wish I could upload a video of it backfiring, but it I tried to upload one that was idling and it was to big.
 
Moms68 said:
Never had luck with Demon, sold it and went to Quick fuel.
Click to expand...

The old demons I never had luck with but the new ones are on the same principle as a quadrojet. They get high reviews.
 
So dumb question.. Its a spread bore intake with a spread bore carb?
 
I'm not too sure the current Demon (which is not very Quadrajet like) is well suited for a big cammed 383. Just speculating.
 
BSB67 said:
I'm not too sure the current Demon (which is not very Quadrajet like) is well suited for a big cammed 383. Just speculating.
Click to expand...
I could buy into that theory.
 
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