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Discussion Starter #1
My 383 engine build came to an end last summer and I finally got a chance to take the car around the block today. It liked backfiring through the carb every once and a while, it was running a tad hot and the carb was smoking after a shut it off for a while.

Here's the specs:
Eagle 383 Kit, 30 over block
Patriot Aluminum Heads
Crane Saturday night special cam

Is there any way I can retune my Edelbrock carb to work with this engine? I'm not looking for max power right now just better driveability. It's not the easiest engine to start and it doesn't like idling very low.

I'm assuming it will help if I change the fuel mixture screw? I wanted to ask before making changes. I have never done carb work before. Any tips here?

 

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Before you do anything, you need to verify your timing. You have a major issue of backfiring thru the carb and that would be the 1st place I would start.

After the timing issue, what kind of cam do you have? What is the vaccum specs of it? I am researching the answer you are looking for on Edelbrocks web site. Have you checked there ?


Dan
 

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IMO 650 is to small for a healthy 383. Which saturday night special do you have? I run a 1050 dominator on my brodix headed, 13:1 compression, saturday night special cammed 383.
 

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It's pretty well known how I feel about those carbs--that would be a good place to start getting rid of problems. But if the car isn't mobile, why bother messing with it now?
 

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Discussion Starter #10
I'm a broke college student who affords the hobby simply because he lives at home and doesn't pay rent.

If I can save a dime and keep the hardware I already have then that would be my best option. I'd rather spend my money getting the car on the road rather then squeezing every possible horsepower out of it. So far the engine seems plenty powerful enough :D
 

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I would disconnect your vaccum advance if not done already, set initial timing to 14-16 degrees and change your mechanical advance springs to softer ones to speed up advance. Then get a bigger carb, never thought the eddys were 650 only 600 i believe. Try a 750 eddy 1407 should be close out of the box. For a little more money you can buy a basic 750 holley vs but might need tuning, I rcommend a 50cc pump kit and a quick change secondary kit but again more money. The timming adjustment alone should fix your problem.
 

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Is this your cam? If it is then its the same cam I run. Not a ton of lift but it has alot of duration. I love it when people tell me the 1050 is way to big. Thats when I show them the tail lights. If it was to big Patrick at Pro Systems would have told me it was to big. Instead he said it was perfectly fine for my combo. The 750 double pumper before I got the 1050 was choking out my engine BIG TIME.

http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=110981&lvl=2&prt=5


EDIT: Looks like you have a dual plane intake? Depending on your cam (if its like mine?) A dual plane is not the best choice. A good single plane is what that cam needs.
 

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THIS IS NOT A MANUFACTURER BASHING THREAD!!!!


For those who think that by adding their .02 cents on bashing Edelbrock, start your own thread. We are here to help this fellow Nova owner out. Its about NPHNP not Holley VS Edelbrock....

Gheesh, when will you wise up and let it go.....



Luke,

you mentioned that you have a Sat. night cam, which one? If possible, could you post the details so we can help you out on where you need to have the timing at?



Dan
 

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Discussion Starter #14
Here's the exact cam I have:
http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=110922&lvl=2&prt=5

I'm running an performer RPM intake. This is a street car. It might see the track once or twice.

Distributor is a standard HEI with electronic ignition added in. Vaccuum advance is still connected.

My carb is the Thunder Series model(avs) which has a 650 version instead of the usual 600's edelbrock makes. It already has the quick tune secondary feature which is standard with the AVS model.
 

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My timing is slightly out. I just need to figure out if the carb will work for my application or if I need to buy a 750
Take care of your timing first, and then work on how it idles. The cam card you linked to below tells you it will have a rough idle.

The 650 should work, once you get timing and carb dialed in, you can upgrade later.
 

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Luke,

nice cam choice. You mentioned that the car hasn't moved much but lately you went out on a test drive to see what you created. ( Who hasn't done that ) And the motor, is it a recent rebuild? What kind of compression ratio are you running?


With that said, 74 Hatchback brought up some points in his posting:
I would disconnect your vaccum advance if not done already, set initial timing to 14-16 degrees and change your mechanical advance springs to softer ones to speed up advance.
You may have to play with this ball park figure until you get the best idle for your set-up.
 

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Discussion Starter #17
Whether or not it would work was the big thing. I'll spend some time trying to time it again. I'm not sure what I should set it at though.

I have 1.6 ratio roller rockers with that cam so the lift is a little bigger then listed. The weather went from sunny and 21 yesterday to rainy and 0 degrees today. It's supposed to stay like this for a few days now so it isn't looking too good.
 

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Discussion Starter #18 (Edited)
Luke,

nice cam choice. You mentioned that the car hasn't moved much but lately you went out on a test drive to see what you created. ( Who hasn't done that ) And the motor, is it a recent rebuild? What kind of compression ratio are you running?


With that said, 74 Hatchback brought up some points in his posting:


You may have to play with this ball park figure until you get the best idle for your set-up.
I'm not too familiar with changing the springs or any kind of tuning for that matter. I was thinking about ordering a 3 piece ignition system for the nova with a coil, distributor and controller. Would that be worth it? The current distributor is really tight against the firewall and the air filter.

Should I run the motor without a vaccuum advance or just set the timing without any advance?

The compression ratio should be right around 10-1. It's running on Canadian premium gas.
 

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If you are running on the street, you want the vacuum advance, but you need to disconnect and plug it when you set the initial timing. Then reconnect it. The suggetion made above should be a pretty good starting point, especially b/4 you get an advance curve kit installed.

If you timed it with the VA connected, you might not get a true reading and may actually have much less initial timing. Your backfire condition sounds like it could be retarded timing.
 

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I'll say it again:turn: disconnect the vaccum advance, set initail timing @ 14-16 degrees advance and get a mechanical advance spring kit and use the weakest advance springs, this will do the job your vaccum advance used to do without complicating your tune, dont worry about cr, ive done this with 11.0-1 and 8.5-1 smblk and bb, 4.10 or 3.31 gears, 3000 stall to off idial, all runs the same, just use the octane your engine likes, I run a HEI with stock coil and a msd6a box with mechanical advance only and daily drive my nova, ive went back and forth with timing and carb issues forever and a day, need to simplify a few things to get it right, most of the time i found the ignition was the major problem and the carb was minor. one can mask the other so start with ignition.
 
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