Is my street avenger 670 too much for my setup, and will putting headers and full exhaust help. I am very dissappointed with my 16.3 at the track.thanks

 

No, a well tuned 670 SA should be just about right, in my opinion.

 

No it's not too much. You just have to jack it up
and slide a motor under it.
Speaking of motors, how did you run that slow of a time
with that good combination of parts?
You should be in the low 14/ high 13 sec area with that stuff.
Are you sure you have "041" heads?
What is the rest of your combination? trans, converter stall
rear gear ratio, pistons, cr, fuel system, tires etc.
Some thing is wrong. I would start looking for the problem with a compression test to see if all the cylinders are healthy.

 

A 670 sounds about right although if it was me I would have gone with a 750 cfm Holley but that's just me. I even have a 750 on a 350 Goodwrench engine for my Blazer. I tuned it just right for it. Great throttle response . A friend of mine suggested I would not be able to tune it for this engine cuz it was "way to big" and then I surprised him. He took it out for a drive and loved the way it responded.

 

my rearend gears are only 2.73 posi and I think the trans is turbo 350 ( I will find out tomorrow). We had timing retarded because it was detonating but then it was detonating off the line at the track. My fuel system is electrical pump into mallory fuel regulator running at the suggested 6lbs of pressure into holley fuel fiter into carb.

 

Check over your ignition system carefully to see if any thing is
causing a miss fire.

Set your timing at 32 deg total with a timing light with vacuum advance temperarly disconnected, at high rpm. (full advance may not occur till 4500/5000 rpm on a stock distributor.)
Then reconnect vac adv to ported vac.
Fill up with 92+ octane gas. You'll never go fast on 87 octane.
What ever spark plug is stock for your car now, select
a set, 2 heat ranges cooler. If you're using AC R45ts now,
get R42T) {Champion RV8C} These combined should take care
of any detonation.
The 2.73's is up to you. Should be 3.73's. If you have overdrive
What are you waiting for?
Pull the bowls off your carb and see what jets are in there now.
Don't assume they are stock or right for that carb, look.
Do you have a posi trac (limited slip diff)?
What was your best 60' time?
What about your exhaust system. Stock/ headers/cat etc???
Anything that will improve your engines ability to breath better will help. Does your car miss,sputteror stumble when you mash the gas?
At any rate your carb is not too much.
The stock qjet is rated at 795 cfm.
Holley vacuum sec carbs are very forgiving in this area. They automaticly size them-selves to your motor's airflow requirements.

 

i'd be inclined to agree that it's OK. Carbs are like cams: there's no such thing as "too much cam", only "not enough motor"; and you have plenty of motor with those double-hump heads.

Headers will make a massive difference in the way your car runs. Don't even bother trying to tune it until you've done that, right now if you still have the stock exhaust you have a fire hose at the intake side and a drinking straw on the exhaust. Get rid of every single piece of that stock exhaust from the heads to the street and put a chassis-specific set of headers, a high-flow cat, and a cat-back for some other one of these cars, such as a 350 TPI. DO NOT get any piece whatsoever that is listed for your car!!!! Doing so will preserve your weenie little LG4 bottlenecks while looking as if it should be free flowing.

 

I am going to do exhaust in acouple months. Today we are going to reset the the timing and strat over. There has to be something wrong.