Car ran slower then expected.

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doogievlg

doogievlg

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Location
Amelia, Ohio
My combo is
360 .30 over
Speed pro flat tops
Mp .484 cam
Eddie heads
Performer rpm intake
Eddie 650 avs

727 with 3000 stall

8 1/4 3:55

Car turned a 13.6 and was missing at the big end. I'm going to bump the timing down and switch to a Holley but the combo should be in the 12s and I don't feel it in it!
 
Car ran slower then expected.

Don't they always LOL.


All kidding aside sounds like you may be running out of fuel pump. The engine combo looks OK. I'm not a fan of the out dated MP .484 cam, but hell I've been in the 11s with one. I'm also not a fan of the AVS style carb either. A good 750 double pump Holley carb would be my choice.



Couple of questions


What compression ratio?
What is the fuel system composed of ie pump and line size?

What MPH in the 1/4?
What is the total timing set at?
What density altitude are you racing at?


12 second time slips should be doable.
 
10:1
Oem style pump
3/8 from pump to carb
Total timing is at 35

I'll post time slips when I get back!
 
Fuel delivery would be where I'd start.
Timing should be good.
Your engine should put down at least 400 HP.
Whats the exhaust system like ? Headers, pipe diameter, mufflers ?
 
Hooker headers with open cutouts. Car hooked great. I am thinking my converter is shot.

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I see you mentioned 3000 converter. If this is one of those B&M or TCI loosened up 11" units, that is more than likely hurting you more than helping you. Those things run very inefficiently. The torque converter is the most important key in getting a car to work. Been down this road once.
 
I thing its fuel on the top end. Just for an example, i have a much heavier car and less HP. My 60 foot times are in the 2.1-2.2 and i run 98 mph in the 1/4

You have a way better 60 foot time, but its laying down on the top end.

I don't thing a stock mechanical fuel pump is enough.
 
hi, whats wrong with the AVS carb?? lots of stockers and super stockers run them. SS/GA darts run mid nine seconds, 340 stockers run high 10 seconds. like anything else , you have to have knowledge to make things work correctly!! some people can , some can't!! changing parts is easy!!
 
perfacar said:
hi, whats wrong with the AVS carb?? lots of stockers and super stockers run them. SS/GA darts run mid nine seconds, 340 stockers run high 10 seconds. like anything else , you have to have knowledge to make things work correctly!! some people can , some can't!! changing parts is easy!!
Click to expand...

I don't know much about building Eddie carbs up. I have a Holley 750 dp sitting on the self so I'll swap it.
 
MPH is really slow for what you have. That should be a 105+ mph set up.

Fuel and ignition would be the first places to look. Which 484 cam, IIRC, there are two a 114 and 108 lsa camshafts. If the 114 LSA, it's a big POS.

A bad converter will cause issues.
 
yeah..... i see all sorts of stockers running 3.55 gears. I would say the the original posters car is a pretty mild street car capable of driving about anywhere.....unlike a "stocker". Personally looking at a few of the specs he's throw our way I'd say it's pretty close. There's a little more, but not much.
 
doogievlg said:
So what pump would you recommend?
Click to expand...

I'm not sure i am the one to make recommendations, but,... i run a elec., carter super pump with an adj regulator set at 5 psi, pushing the MP mechanical pump. Pushes 9 psi to the carb at idle, 7 with the elec. turned off.

I turn the elec pump on just before the burn out box.

Note: the regulator is a return fuel system and i have the elec pump and regulator at the fuel tank.
 
A body said:
yeah..... i see all sorts of stockers running 3.55 gears. I would say the the original posters car is a pretty mild street car capable of driving about anywhere.....unlike a "stocker". Personally looking at a few of the specs he's throw our way I'd say it's pretty close. There's a little more, but not much.
Click to expand...

The car runs great. I sat in line at tech for 30 minutes and the car never went past 180. I'm going to research the fuel system and maybe change the pump and line. Then next is ignition.
 
perfacar said:
hi, whats wrong with the AVS carb?? lots of stockers and super stockers run them. SS/GA darts run mid nine seconds, 340 stockers run high 10 seconds. like anything else , you have to have knowledge to make things work correctly!! some people can , some can't!! changing parts is easy!!
Click to expand...

Those stock / super stock racers that run AVS carbs do so because they have to. Most of the guys running AVS cars have spent a LOT of time and money getting those carbs to work well. If given the green light to run any 4 bbl carb of their choosing, they would all jump ship to something else.
I recommended the 750 Holley because they flat out work, without spending a lot of time and money. I not saying that the AVS is crap, but Holleys work better the majority of the time.
Take your own car for example. You changed out the 8 3/4 rear end for a Dana 60, and changed the 833 trans for a Jerico. Why ? Because neither the 8 3/4 or the 833 at their best, were as good as the parts that replaced them.
Some times changing parts makes the most sense.
 
Interesting... my combo is close. I got a 1.78 60' out of mine and I have 3.55's with a 28" tall tire. I think mine has more in it if I ran a 26".

I don't think you need to change too much. What does your car weigh with you in it? I'm at 3550.

I bet a good Holley would help it. I don't know if a 750 is necessary, my 650 dp is a little rich. I'm haven't had a chance to try a bigger carb.

As far as pumps I have one of the street/strip pumps, I think its 110 gpm... 3/8 lines.

Good luck
 
3/8 fuel line is plenty big enough for your combo, so I would leave that alone. the first thing I would do is get rid of the AVS and put on a Holley with a close tune. see how much that picks you up before changing the next thing.

the next thing would be to go to a hi flow mechanical pump like a Carter or Holley.

if nothing then start looking at converter.
 
What speed pro pistons are you running, are they the "hypereutectics"? If they are you will be nowhere near 10:1.
 
raymond said:
What speed pro pistons are you running, are they the "hypereutectics"? If they are you will be nowhere near 10:1.
Click to expand...

Yes they are. I got that number from other builds. I haven't had time to run a compression test.

The converter will be the last thing to be replaced simply because I need to save some
More money and I am not in a hurry to pull the trans anytime soon.
 
A compression test will not tell you the compression ratio, just how close all the cylinders are to each other. Cranking compression is affected by many things inuding the cam specs. The only way to truly know your compression ratio is to calculate it. You need to know head gasket thickness, combustion chamber volume, bore, stroke and deck height above the pistons for this.
 
find out why its missing first..

then i think it needs more gear, and more carb. i'd say a good built to your combo converter too.. but the miss is the first thing that needs to be addressed.


my dart ran with a stock fuel pump and 5/16 line all the way to the 750 double pumper and i never had any issues... best run was a 12.17 at 108.9 mph. consistent 12.2-12.3 car.
 
I run the Carter high volume mechanical fuel pump on my 64 Sport Fury. Been 12.12 @110. Don't have all the issues that come with an electric pump( wiring, rerouting fuel line, mounting, etc). I would leave the timing alone for now, and upgrade the pump, and switch to the Holley, but take some jets and squirters to the track with you, so you can see what the car likes.
 
Initial timing? My guess should be around 20-24 degrees minimum with that camshaft. Fix the mechanical to hit your total number. Then curve it using lighter springs.

I'd bet the carb is going lean.

Pull a plug and look. If porcelin has got speckles on it, too much total timing. Running closed chambered Ede headed? They tend to like in the 32-34 range, especially on std pump gas. Yours may be different, that's the range I've seen that works well.

As mentioned, figure out why it's missing, laying over.
 
Doogie, the main reason i added the elec. fuel pump was for starvation.... but it was more heat related then any thing.
Isolating the fuel line were it runs in front of the headers helped a bunch, but the pump took the problem away on a hot summer day at the race track.
 
doogievlg said:
My combo is
360 .30 over
Speed pro flat tops
Mp .484 cam
Eddie heads
Performer rpm intake
Eddie 650 avs

727 with 3000 stall

8 1/4 3:55

Car turned a 13.6 and was missing at the big end. I'm going to bump the timing down and switch to a Holley but the combo should be in the 12s and I don't feel it in it!
Click to expand...
Welcome to the not running the times you expect should run club ! I can't break 13.3 and I know the car should run 12's . Dyno tested 398 hp 413 tq Mahle 10.5 forged Mahle pistons , light port on the stock heads , Air Gap 750 holley street avenger , 8 3/34 3:55 gears stock 340 converter and a Gear Vendors overdrive . 235 60 15 M/T drag radials .
What are your rpm when crossing the line ? I'm at 5300-550 rpm in 2nd overdrive crossing the line .
Going to follow this thread with interest .
 
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