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Blackpony
03-13-2009, 01:52 PM
I am having a few minor problems with my carb hopefully sopmone can answer for me. First off my carb is a street avenger 670 cfm and the problem i am having is it is spuddering slightly when i axcelerate. I have made some adjustments but maybe a fresh mind might help. I have also replaced the timing chain so my thought is that i need to adjust the timing to meet the carb. My only other thought is to drive the damm thing into a tree. Any help would be great.
satan jamez
03-13-2009, 02:27 PM
I had the same carb and intake on my 88lx. I also had the same issue as you have. Richen up the front jets 2 sizes and drop the rears 1 size. Basically, just keep increasing the fronts untill the issue goes away, then back off the rears 1 size. This will get you in the ball park :)

The fronts are 67's stock and I went to 69's. (correct me if i'm wrong, it's been a while)
Black Horse
03-13-2009, 02:58 PM
You might also want to check to make sure your power valve (accelerator pump) hasn't blown the diaphragm or is leaking. One good backfire can wipe a power valve out.
Size your jets based on running fuel mixture (best done on a dyno) and size your power valve by throttle response.
Blackpony
03-13-2009, 03:04 PM
You might also want to check to make sure your power valve (accelerator pump) hasn't blown the diaphragm or is leaking. One good backfire can wipe a power valve out.
Size your jets based on running fuel mixture (best done on a dyno) and size your power valve by throttle response.

Never had a leak or backfire yet. This carb is less then a month old. I did read on another forum that the carbs were set to run lean and others were having the same problem.
juiced347
03-13-2009, 03:54 PM
Never had a leak or backfire yet. This carb is less then a month old. I did read on another forum that the carbs were set to run lean and others were having the same problem.

holleys are dirty as hell when new take it off and do a basic clean on it you will be surprised at the amount of metal shaving come out of it
Blackpony
03-13-2009, 04:01 PM
holleys are dirty as hell when new take it off and do a basic clean on it you will be surprised at the amount of metal shaving come out of it

I'm going to take a trip to cincy speed tomorrow and get bigger jets. Then before i install them i'll clean the carb and see what happens.
juiced347
03-13-2009, 04:22 PM
I'm going to take a trip to cincy speed tomorrow and get bigger jets. Then before i install them i'll clean the carb and see what happens.

if I didn't live so far away I would let you try my carb
Timido
03-13-2009, 06:58 PM
If it is a basic holley design make sure your float levels are correct and install a Jet extender also.
69Cobra
03-13-2009, 10:46 PM
Like Dave and Tim said. Check the power valve, accelerator pump, float levels and also add the jet extentions. Take it apart spray it out with carb cleaner and make sure you don't have any vaccum leaks. Make sure the throttle shaft is tight in the base plate. Check the diaphragms on the power valve and the accelerator pump. Hope that helps.
Blackpony
03-16-2009, 02:15 PM
I went ahead and changed the jets and it worked. I did find some metal shavings inside the carb which i cleaned out and it's running great. Thanks for all the help guys
satan jamez
03-16-2009, 08:23 PM
Glad to hear that was all it needed :)