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Author Topic:   jet size ???
nwracr
Dirt Full Roller

Total posts: 49
posted November 20, 2002 12:19 AM  
on a totally stock, i am assuming, 2.3 with a holley 350 what jet size should i start with? anyone have any suggestions?

Earl Parker II
Dirt Full Roller

Total posts: 69
posted November 20, 2002 09:24 AM  
I would recommend starting with stock jets, which are 61s.

When you start your tuning efforts I would change jets two sizes at a time, at least to begin with. I would start by running a baseline with 61s, then I'd go up to 63s and run another test. If the engine ran better, I'd go to 65s and repeat the test. As long as it continued to run better, I'd go in the same direction until it no longer ran better. If you go up to 63s and it doesn't run as well, then I'd go to 59s and repeat the procedure outlined above.

The whole idea is to first go one way then, if necessary, the other to find the jet size that's best for your combination. Of course, once you get close, then change one size at a time to find the exact jet you need.

Since cylinders #2 and #3 can be over fueled (depending upon the intake your using), you might experiment with a smaller jet size on the ‘inside’ to see if that helps. You can also try an ‘offset’ pump nozzle, with a smaller hole on the ‘inside’. Of course, these strategies work best if #2 and #3 are over fueled to begin with- if all the cylinders look pretty much the same when you check plugs then I probably wouldn’t worry about it.

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Earl Parker II
www.parkercarburetion.com
704.482.7588

nwracr
Dirt Full Roller

Total posts: 49
posted November 20, 2002 05:07 PM  
i put the carb on, it was on a 302 is why i asked about jet size. it idles fine , with flames coming out the exhaust. when i rev it quick the flames die a little but then it backfires, but it runs great, i only did this once and don;t want to mess with it again til i here from some of you. there are just too many flames. i don't know much about carbs as you can tell and just wondering if there is anything else like timing maybe, that may effect this. thanks for any help.

[This message has been edited by nwracr (edited November 20, 2002).]

Earl Parker II
Dirt Full Roller

Total posts: 69
posted November 21, 2002 03:02 PM  
Timing can certainly affect it, as can idle system settings. One possibility is that the throttle butterflies are too far open at idle.

If you would, remove the carburetor, drain it of fuel and give me a call at 704.482.7588. The fix for the problem would take quite a lot of typing but I can explain it easily over the phone, plus I can ask whatever other questions need to be asked.

Feel free to call any day up to 8:00 PM. Don't worry about getting in touch as this is a no-stings attached offer.

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Earl Parker II
www.parkercarburetion.com
704.482.7588

SKULLHULL
Dirt Full Roller

Total posts: 69
posted November 21, 2002 08:24 PM  
flames out of pipe is most likely in ignition system , out of time, bad dist cap, or bad plug wires.or just hooked up wrog to the dist. also check the fireing order.

nwracr
Dirt Full Roller

Total posts: 49
posted November 21, 2002 11:58 PM  
well i checked the timing, same as before the carb or ignition work. ignition system seems to be fine, new cap, rotor, plug wires. i'll be istalling a new coil soon. the motor runs great it just has flames at idle and on decel. it did start to get hot and the exhaust got pretty bad.

Earl Parker II - thanks, i'll take you up on your offer, give me a couple days to get some time. i wanted to ask you if the acc. pump could be involved it seems a little off to me. thanks again.

[This message has been edited by nwracr (edited November 22, 2002).]

Earl Parker II
Dirt Full Roller

Total posts: 69
posted November 22, 2002 07:10 AM  
nwracr,

While the accelerator pump system may need some work to make sure it's optimized, I doubt it's involved in your flaming problem. What you're describing is generally the result of an incorrectly setup idle system. The nice thing is that as you solve your flaming problem you're also going to be improving your throttle response and acceleration.

You definitely want to make sure that both base and total ignition advance are where they should be, though it sounds like you already have those bases covered.

I'll be available today, will be out of town this weekend and back in town Monday. Look forward to hearing from you.

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Earl Parker II
www.parkercarburetion.com
704.482.7588

nwracr
Dirt Full Roller

Total posts: 49
posted November 22, 2002 10:57 AM  
thanks, i'll call you monday.

Earl Parker II
Dirt Full Roller

Total posts: 69
posted November 26, 2002 09:07 AM  
nwracr,

If you call me and there's no answer, please leave a message and I'll definitely return the call when I get in.

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Earl Parker II
www.parkercarburetion.com
704.482.7588

buckseight
Dirt Maniac

Total posts: 150
posted November 28, 2002 07:43 AM  
I'm tellin ya; you cant ask for a guy better than that.earl your a top notch guy.I'm not trying to blow smoke or anything but i've seen it time after time reading different posts here and other forums this guy goes out of his way to help people with straight answers,earl have a very happy thanksgiving
and happy holidays.

Earl Parker II
Dirt Full Roller

Total posts: 69
posted November 28, 2002 06:15 PM  
buckseight,

Thank you for the kind remarks. I do my best to stick to the straight answers as no one will buy the crooked ones. Don't overeat too much.

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Earl Parker II
www.parkercarburetion.com
704.482.7588

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