Why does my car feel sluggish?

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magnumdart said:
You could try another carb. The engine will handle it. But I have to go with you need a different gear. That would be a great gear for a 440. First thing I thought when I read your post. You still should check timing, compression, all the other things mentioned. How is the acceleration from 90 on up?LOL
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The problem with going for more gear is that the is then car is worthless on the street. 3.91s/4.10s puts me at what 10mpg on a good day? There's no point in even having it street legal at that point. I'll be spending a couple hundred bucks every track night.
 
what size tire is on the back? Gear ratio is one piece of that puzzle. If the tires are short the gear you have is not an issue. if they are 30" tall then you have some issues.
 
Don't start throwing money at it. The only thing i'll agree on (other then a bad tune) is the carb being too small, put a real carb on it, not a kids carb, don't build something that you want to run then put a wimpy carb on it, why does so many do that. I'd check the tune, make sure its good, run a compression test just to make sure all is well, This is what i had & it was similar to yours, I pulled off 12.5s all day long shifting at 5100, you have a little more stall/cam then i did, I ran 3.73 gears, My junkyard magnum was a torque monster, check out the video in my sig, I ran right with a 69 Yenko 427 Camaro with my junk. The biggest mistakes i see many make is running too small a carb & crappy ignition. Check the obvious 1st.

71 Dart
360 magnum (stock short block un-rebuilt)
RHS heads
Re-ground tock cam from bullet ".477,.477, .218, .218@50 on a 112
Stock rockers/lifters/pushrods
Crappy Crosswind RPM
650dp
Summit 1.5/8 headers.
PTC 11" 2800 stall
3.73 gears

MSD dist. & Mallory box
10* int., 30* total all in at 2200
NGK plugs

Ran on 87 octane

Drove car 100 mile round trip & pulled off 8.0s & 12.50s @ 105 On motor

Threw a 125 shot at it a few times, the 1 time it hooked ran 7.4s 1/8 letting off.
 
JoeDust451 said:
Don't start throwing money at it. The only thing i'll agree on (other then a bad tune) is the carb being too small, put a real carb on it, not a kids carb, don't build something that you want to run then put a wimpy carb on it, why does so many do that. I'd check the tune, make sure its good, run a compression test just to make sure all is well, This is what i had & it was similar to yours, I pulled off 12.5s all day long shifting at 5100, you have a little more stall/cam then i did, I ran 3.73 gears, My junkyard magnum was a torque monster, check out the video in my sig, I ran right with a 69 Yenko 427 Camaro with my junk. The biggest mistakes i see many make is running too small a carb & crappy ignition. Check the obvious 1st.

71 Dart
360 magnum (stock short block un-rebuilt)
RHS heads
Re-ground tock cam from bullet ".477,.477, .218, .218@50 on a 112
Stock rockers/lifters/pushrods
Crappy Crosswind RPM
650dp
Summit 1.5/8 headers.
PTC 11" 2800 stall
3.73 gears

MSD dist. & Mallory box
10* int., 30* total all in at 2200
NGK plugs

Ran on 87 octane

Drove car 100 mile round trip & pulled off 8.0s & 12.50s @ 105 On motor

Threw a 125 shot at it a few times, the 1 time it hooked ran 7.4s 1/8 letting off.
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Well in my defense the carb wasnt a new purchase for the setup. It came on the car and i had hoped it would be enough and just hold back the car a little.

And i'm certainly not trying to just throw money at it, but if its the tune/ignition then it seems logical to upgrade atleast the carb before i hit the dyno to get a good accurate tune.
 
crackedback said:
what size tire is on the back? Gear ratio is one piece of that puzzle. If the tires are short the gear you have is not an issue. if they are 30" tall then you have some issues.
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right now it has some 17s and 245/45s. Which is a 25.7" tire. Down the line im gonna pick up some cheap drag wheels and just run a small 275 drag radial/slick on 15s
 
You DO NOT need more gear!

If you put the 275/60/15's on it, it will likely need more gear.
 
Maybe my ignition box is also shot/not working as well(see pic)

And a friend of mine is thinking that my replacement dist.(oem parts store replacement) might not have a good ignition curve as its likely set to fit multiple mopar small blocks in multiple applications.
 

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If you have 16 initial, I'll bet it's got way too much total and you may be detonating which will smoke head gaskets or worse.
 
You need to find out how much advance is in the distributor AND the stock curve can be painfully SLOW. Some aren't all in until 4000+ rpm.
 
crackedback said:
You need to find out how much advance is in the distributor AND the stock curve can be painfully SLOW. Some aren't all in until 4000+ rpm.
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How do i find out how much advance there is and how can i change that stock curve?
 
Several people have asked you what your " TOTAL" timming is, and you couldn't answer.
Set your TOTAL timming to around 34deg. See if that helps. Then you will be able to figure out what kind of advance is built into your dist.
Your 600 Ede should work fine, only loosing at the top end to a bigger carb.
 
timing tape on the balancer and rev it up until it stops advancing. Subtract initial timing number from the number you get when it stops advancing, that's mechanical in the distributor. Some of those mopar distributors have 24+ degrees in them. So if it has 24 in it and you have 16 initial, it's got 40 total

Find the total number it will run on without detonation, set initial timing to what the engine wants, then tailor mechanical to hit total number, then change spring to get curve in quicker.
 
Johnny Dart said:
Several people have asked you what your " TOTAL" timming is, and you couldn't answer.
Set your TOTAL timming to around 34deg. See if that helps. Then you will be able to figure out what kind of advance is built into your dist.
Your 600 Ede should work fine, only loosing at the top end to a bigger carb.
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No, i've answered plenty of times. "I don't know" is an answer.
 
magnumdust said:
And a friend of mine is thinking that my replacement dist.(oem parts store replacement) might not have a good ignition curve as its likely set to fit multiple mopar small blocks in multiple applications.
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Now you're on to something. A stock timing curve won't work in a modified engine.
 
crackedback said:
Get rid of the taxi cab carb.

Time it at 16 initial and about 32-33 total all in at 3k or a little less.

Should idle easily at about 800-850, even less.
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lol i hear that ,no eddy carbs on a real hot rod
 
You need to upgrade that ignition, i personally won't waist my time on factory stuff in a HPerf. build anymore.
 
I've run stock ignition to 11.450's on juice.
You must set it up properly.
I wouldn't be afraid to run a Thermo 850 carb it's a vac carb.

Cam card seems wrong.
.321x1.5=481 lift.
Set total timing atr 36 and go from there.
Get a good coil.

IMGP0512.jpg


Trainer car still doe's 11.40's
IMGP0481.jpg
 
Johnny Dart said:
You need to set total timming. It's all basic stuff, learn the basics.
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Apparently that will be what i'm doing saturday then. Being that my friend's build dozens if not hundreds of cars, i was willing to take his word for it.

Also found something interesting that may be a key part of this too. Last night i was playing around with the car and the shift points are not remotely right. From a standing to start to WOT, it doesn't seem to revv over 3-3500rpm until i'm in 3rd. Which from what i was able to find through search has to do with the governor & kickdown in the transmission.
 
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