Why does my car feel sluggish?

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AdamR said:
16 initial is ok but you need to weld the advance slots up a bit to get total down to 36-38 then swap some springs around to get it all in around 2500rpms.

Have a friend hold the gas to the floor (motor off) then see if its opening the throttle blades all the way buy moving the lever back by hand.

Is your kickdown rods from a 4bbl car ?
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Probably not 4bbl kickdown. The last owner/previously builder kind of cut corners on virtually everything.
 
Badsport said:
That's probably the better way, that way you can tell if everything is working correctly.

16* initial is a good start. You might eek out a couple more degrees out of it. Ideally like Adam said you want 36-38 all in by 2500 at the most.

You are doing this with the vacuum advance unhooked and plugged, correct?
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Yeah its plugged. Atleast when i'm taking the timing readings.
 
magnumdust said:
Probably not 4bbl kickdown. The last owner/previously builder kind of cut corners on virtually everything.
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It may makes thing a bunch easier if you locate a 4bbl set up. Honestly when I bought my 69 Barracuda with a warmed up 340, 727 and 323s I had the same issues. It felt real sluggish. I could tell it had balls but something just wasnt right. It had no kickdown at all so I put a T/V manual valve body in the car and it made a big difference.
 
magnumdust said:
Maybe i'm looking at this wrong, so here are some pics:

Looking down the rear of the carb i see this plate(1st pic not wot) and at WOT(2nd), it doesnt seem to move.
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What you are seeing in the secondaries is the air door plates. You need to put a screwdriver done there and open that up to see the actual throttle plates.

The kickdown, have someone hold pedal on floor, go under car and disconnect the linkage. See if it swings further back than where it is at full throttle. My guess is the upper arm is too short and not properly applying full range to the arm at your trans.

OR

Hold the throttle wide open, then push back on the kickdown rod at carb, if it moves back a bunch more you need to address that.
 
Ok, good deal on the numbers. In regard to the total... Did you rev higher, or stop at 4K? My impression is it will keep advancing even further. But... It's easy to recurve what you have for about $30. $7 in parts for the light advance springs from Mr Gasket, and the rest to a guy at a local muffler shop to weld up the last .25% of the slots in the advance plate. While the kickdown is not perfect, My impression is it's "ok". You can also use a very small bolt and nut and washers to make the slot in the adjuster shorter and get some of that kickdown back.
 
crackedback said:
What you are seeing in the secondaries is the air door plates. You need to put a screwdriver done there and open that up to see the actual throttle plates.

The kickdown, have someone hold pedal on floor, go under car and disconnect the linkage. See if it swings further back than where it is at full throttle. My guess is the upper arm is too short and not properly applying full range to the arm at your trans.

OR

Hold the throttle wide open, then push back on the kickdown rod at carb, if it moves back a bunch more you need to address that.
Click to expand...

How far are the secondaries supposed to open at WOT? It seemed like mine only opened about 1/8th of an inch at WOT.

Also, held throttle open and pushed kickdown road and it doesnt move any further back.
 
moper said:
Ok, good deal on the numbers. In regard to the total... Did you rev higher, or stop at 4K? My impression is it will keep advancing even further. But... It's easy to recurve what you have for about $30. $7 in parts for the light advance springs from Mr Gasket, and the rest to a guy at a local muffler shop to weld up the last .25% of the slots in the advance plate. While the kickdown is not perfect, My impression is it's "ok". You can also use a very small bolt and nut and washers to make the slot in the adjuster shorter and get some of that kickdown back.
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any only guides to taking apart one of these oem distributors to have this done?

I'd be thrilled if i could get the total timing right without having to re-do the ignition system to an MSD/pertronix. Atleast for now.
 
magnumdust said:
any only guides to taking apart one of these oem distributors to have this done?

I'd be thrilled if i could get the total timing right without having to re-do the ignition system to an MSD/pertronix. At least for now.
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Did you check out the link I posted?
 
Badsport said:
Did you check out the link I posted?
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oh, i just double checked that link. First time around i missed where they showed the limiting plates. Maybe i'll just do that w/ lighter springs instead of welding and guestimating.
 
On the carb - There is an air door over the throttle plates in the secondaries. You have to hold that door open when looking down the bore.
 
moper said:
On the carb - There is an air door over the throttle plates in the secondaries. You have to hold that door open when looking down the bore.
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yeah, i rechecked it earlier holding that air door open and the actual secondary plate only opened about an 1/8th of an inch at full throttle.
 
magnumdust said:
On the last bit, was gonna do that today, but the pouring rain made things a little difficult. However, after getting what seemed to be an accurate timing made me think that it is not an issue.
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The accurate timing doesn't have much to do with it. If the thing has spun 10*, then the initial timing you think is 16 is really 6, and total is really 34, etc.

If the thing isn't running right at 10* initial, its a fair bet something goofy is going on. Of course that's low for performance, but it should at least run.

Also, its not really going to have a lot of oats at 3000 RPM, so that early shift is perhaps a large part of your problem.

Lots of good advice in this thread.
 
just on a side note , and im not trying to throw jet dryer fuel on the track, but , personally, when you are happy with your timing, just for *****, i would have already had two or three carbs waiting to bolt on and try. i didnt catch what carb is on there now.. #1 edelbrock performer 650 #2 holley 650 and a 750 DP holley all vacuum secondary with the frickin chokes tied wide open. there is so much emphasis on the timing that the fuel delivery is getting overlooked. i think it MAY be under carbureted for starters just MO ...edelbrocks are overrated IMO...one more thing, if that thing does not shred pavement with a nice holley 750cfm DP then there is definately something else going on..ok let the beatings begin LOL
 
magnumdust said:
yeah, i rechecked it earlier holding that air door open and the actual secondary plate only opened about an 1/8th of an inch at full throttle.
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Yeah that's a problem. You need to get the throttle cable to open the carb all the way. Maybe a stud location closer to the shaft axis.

5/8 throttle will be a dog.
 
LXguy said:
The accurate timing doesn't have much to do with it. If the thing has spun 10*, then the initial timing you think is 16 is really 6, and total is really 34, etc.

If the thing isn't running right at 10* initial, its a fair bet something goofy is going on. Of course that's low for performance, but it should at least run.

Also, its not really going to have a lot of oats at 3000 RPM, so that early shift is perhaps a large part of your problem.

Lots of good advice in this thread.
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well if its not pouring rain tomorrow, i'll see what i can do about testing that theory.

As for the early shift i think your right, and i'm thinking i may look into a manual valve body for it + a ratchet shifter on my next paycheck.
 
I think you will be wasting your money, time and creating a whole nother list of problems by changing the valve body. Get a 3 piece kickdown linkage off ebay or modify the one yoy have so that it is all the way back at full throttle. I had similar issues with my new build and it was all in getting the distributor set right, adjusting the carb and trans linkage etc... I would say if you do not know how to or have the means of welding the slots in the distributor, to buy a new M.P. quick advance unit. it will be much easier for you
 
gliderider06 said:
I think you will be wasting your money, time and creating a whole nother list of problems by changing the valve body.
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I agree, address the issue at hand first, then go with the goodies after you get it running in an optimal state.
 
crackedback said:
Yeah that's a problem. You need to get the throttle cable to open the carb all the way. Maybe a stud location closer to the shaft axis.

5/8 throttle will be a dog.
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I dont think its the throttle cable, the cable pulls the linkage to WOT, its just that the secondary plate doesnt fully open. Though i'm not sure if its suppose to with the engine off?
 
with the gas pedal to the floor can you open the throttle more by hand ?
 
How does it pull to wide open when you say the rear plates are only open 1/8 of the way.

Is it the air door at 1/8 or the bottom throttle plates at 1/8 open. BIG DIFFERENCE!
 
Here's your list:

Junkyard 360 magnum(turned out to be a freshly rebuilt engine)
Hughes Iron ram heads(stock 1.9x valve)
Custom ground cam from IMM
crosswind air-gap intake
3000 stall convertor
Hedman headers
3.55 gears
edelbrock 600cfm carb
Timing set at 16 out.

Specs on the cam(though i know zero about them):
Gross valve lift: intake/exhaust: .513
duration @ .006: 276/282
duration@ .050 : 224/230
Lobe lift: .3210/.3210
Lobe duration: 110

It all looks really good to me except for two things. First is the carburetor. Although you need a larger one, that will pretty much only effect mid range and top speed. But, the larger venturis of a larger carburetor would help a little. The biggest problem I see is with the gear and the converter. They are mismatched. Either get a converter close to stock, or step up to a 3.91 or 4.10. Everything else in your combo matches up to gears lower than a 3.55, IMO. To me, the most logical choice would be a Holley 3310 750 and a 4.10 gear. That would set it on fire. All this is just one peon's opinion of course.
 
what brand converter ? If its a cheap one it may be to loose and way inefficient.
 
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