well i need help bad any held.I need to know what can cause my car to bog down i have replaced all gas lines rebuilt the carb brand new fuel cell.I mean i have replaced every thing that has to do with gas.So what else is there.Any help would be great.THANKS.and this is only at the strip.
Bog is usually considered a carb problem. However there are other mechanical causes at times. Often in the valvetrain. Weak valve springs can feel like a bog when pushed hard, for example.
Just because the carb is "rebuilt", doesn't mean that it is truly tuned. That's my story, and I'm stickin to it!
What 411 said monster,You need to optimize/tune the whole system.Make sure every thing is working as advertised.Then tune it.
well just played around with it timing is fine card is tuned just right and my dad checked the valves its all good he thinks it needs bigger cam. i have a stock cam with performance parts what do you guys think.
is it really bogging or is it at it's limit. a new cam should help it rev higher, if everything else is up to par. if it's bogging and has some more in it check the fuel pump, filter, or the float levels.
If you got a stock cam, and it is bogging at the track when you are pushing it hard... You are floating the valves. It is probably not even one part of the valvetrain causing it either. I'd say it's a combo of worn parts, weak springs, and stock parts pushed to their limit. Valve float feels like a bog at first, then feels like you hit a wall when you reach the limits of the valvetrain. Sorry, but you can't say that until the car is running right! The carb may not be the culprit here, but the carb is always the last thing to be tuned and the first thing to look at when there is a problem. To tune the carb at idle, then just declare it done is a mistake. If there is a problem like a bog, the carb is always a suspect no matter how well you tuned it at idle.
This is probably a stupid question, but when you rebuilt the carb.....I assume you replaced the accelerator pump.
If it's bogging down, I don't relate that to a lean condition, bogging is a different thing. Could be timing retarded too. If the carb is too big, but tuned correctly (as to the air/fuel ratio) it can also bog down. Too much airflow (too big a carb, i.e.; something like an 850 Holley DP on a 302) will make it bog, you don't have enough vacuum when all the throttle bores are open to make the carb circuits work, that will make it bog down. You need to be a bit more specific for anyone to help solve the problem. I also see that this is only a track problem ? That could be too much traction, and/or not enough torque to get the car moving. I've seen ricers that ran 12 sec 1/4's but when they dumped the clutch on the line, the traction was enough to kill the engine, that's bogging down.
Yes we need more info to help you diagnose the issue.AS you see there are many things that can cause what you are experiencing.Need specifics.Speed/rpm/ operating temp/timing specs etc... Heck it could be as simple as a bad coil.need more info please.
That's a really good point D... When I got my 75 all together, but hadn't got around to building the rear yet, it had a 3.00 gear. I just had to take it to the track, though I knew I had far too much in my combo to work with 3.00 gears. I got better times dumping the clutch and spinning the tires down almost the entire track, compared to feathering the throttle and coming off the clutch normal. The engine didn't make power until 2500 rpm, so it just fell on it's face terrible! That was the result of keeping traction. When I forced wheel spin, I didn't go fast, but it didn't bog! With 3.00 gears, I had just under 3.0 60' times and the car would float the valves across the traps in 2nd gear! If I shifted into 3rd, I lost ET/MPH. Best time with 3.00s was 8.4/85 IIRC... No traction and only 2 gears. Needless to say, the car was much more fun to drive with 4.11s. I wish I got it back to the track with those, but never did. The car seemed MUCH faster. Anyway, I am getting off topic. Just thought that was a good point. However, my problem was due to traction with a large cam mixed with hiway gears. He has a stock cam. I wouldn't think you could out traction that, unless he has some outragous combo like a really aggressive intake and/or a really big carb.
i am running a 600 edelbrok carb. And it has a rear end out a 73 maverick that had a 302 what ever those gears where.As for traction it does fine and i know the internal parts are fine they are less than a year old every part.
I'm not familiar with Edelbrock carbs (other than they're too butt ugly for me to use and complicated) but if it's a mechanical secondary, that could be the problem (but it seems not with only a 600) The rear gear, I'd bet is 2.79's. That's more likely the reason, if you've got a posi unit. What's your initial ignition timing set at? If it's the factory spec'd 6* BTDC, that doesn't help either. Needs to be at least 10*BTDC.
