Hi Everyone,

Total newbie here, and I'm hoping to draw on the experience and knowledge of you to make my 69 a street worthy car.

When I got the car, it was completely bone stock and ran strong. I could spin the back tire with ease on a stock 350 with a 2bbl carb and exhaust manifold. A friend helped convince me that putting a holley street avenger (4bbl 670 cfm double pumper) on top of a edelbrock torker would make the car much faster.

Ever since I made the switch, the car has lost all of its low end power it seems. It seems very sluggish and doesnt wake up until about 30mph (I don't know RPMS)

To make things worse, since sitting in my garage for a few years, it's even more sluggish than before. It dies frequently when beginning to accelerate from a dead stop, and forget about going fast at all. I can barely make it around the block.

I'm tempted to put the stock intake/2bbl back on there, and be done with it, but I figured I would at least TRY and get explanations as to where I am going wrong, advice on what to do, and learn a few things to make this car an awesome ride I know it can be!

Thank you!

Welcome Newbie,

You probably have hiway gears (2.56, 2.73) in your rear end thus your low end will be slower than say 3.43 gears.

Also, the double pumper will bog down with this setup as your engine is unable to get hi rev's quick enough to use all the gas your double pumper is shouting into the intake.

First, find out what gearing you have. If you want to have a street racer then you wanna have something like 3.4+ gearing in a Safe-T-Track (POSI) Pontiac rear end.

I would also recommend using a stock QuadraJet /w stock 4 bbl intake.

Info on axle codes: https://firstgenfirebird.org/f-a-q/axle-code-facts/
Here is a rear end ready to go for you... https://firstgenfirebird.org/forums/ubbth...6681#Post286681

Agree. I'd say your "friend" did you a disservice.

Stock intake and quadrajet would have been the way to go, but would not have increased performance too much more than 100% stock.

Agree with gus on the induction. Torker is just the name of the intake not a description of what it does.
A stock four barrel or Performer dual plane is a better choice than the Torker. I don't have enough experience with the street avenger to comment on the carb.
Manifolds are RPM sensitive, both the stock four barrel and the Performer manifolds are designed to run from idle to about 5,500 RPM, Edelbrock RPM from 1,500 to 6,500RPM. The Edelbrock torker is a 3,500 to 7,000 RPM intake.
Dual plane intakes will have a higher velocity of air/fuel charge at lower RPM than the single plane. They run more efficiently at lower rpm. Dual planes run better at low RPM and single planes run better at higher RPM
Low fuel/air velocity at lower RPM of the Torker will cause bad off idle response and bad milage.
One must match the induction system to the cubic inch displacement of the engine, the types of heads and the intended use of the car.

Totally agree with Bluebird. A Torker intake manifold is one of the WORST things you could do to a relatively stock Pontiac V8. Total mis-match.

That one move right there killed all your low end torque and drivability.

Hmmm, If you left your car sitting in the garage for a few years and now you can barely make it around the block, you may have a gummed up carb. Any fuel sitting in the carb for long periods will go skunk and laquer up the internals.

Good point! Especially with the mandated ethanol crap at the pump these days.

There has been a ten fold increase in gas stations selling non-ox fuel in my area this past year. I hope ethanol will be gone for good in a couple of years. (OK, off my soap box now) I feel much better now.

A torker intake needs a high lift radical cam and steep gearing to get the RPMs up off the line. You need 3.90 or 4.11 gears to make that intake work.

"A friend helped convince me that putting a holley street avenger (4bbl 670 cfm double pumper)..."

A: A Holley Street Avenger is a vacuum secondary carburetor. Not a "double pumper"
B: Change " A friend" to "an X-friend"

The carb isn't bad (relatively speaking). The intake is your problem. Easy fix. Change it. I may have an E'brock Performer intake manifold if you're interested(cheap). Send me a PM.

How many different stock 4bbl intakes are available for 350, 400 Pontiac engines?

Can new tech Pontiac engines achieve 7000 RPM?

Yes...if built correct. But...since the bore/stroke/head ratios and flow characteristics with Pontiac engines develop torque and horsepower roughly 1500-2000 RPMs less than say a Chevy small block, there is no need for 7k. If one had a 303 RAV....

The 7k is a reference point for broad marketing.

Thank you all for the warm welcoming and advice. I looked for a stock dual plane manifold but ended up finding a performer for a good price with free shipping (sorry, Bronze, I just saw your post).

It appears that my 80670 Holley carb is not a double pumper (told you I'm a newb) so I'm hoping that I don't have to invest in another carb.

Well, in addition to getting your low throttle performance back, you will also shave a few extra pounds of a car that's naturally nose heavy.

Sounds like a good plan and a 670 CFM carb should be a good match for the 350. Holley states they're "tuned for the street" I can only assume they tune a 670 CFM carb for an engine in the 350 CID range?
Don't be too hard on your friend, he/she just didn't know any better.

UPDATE - I purchased an edelbrock performer and installed it this past weekend. I also learned that my holley carb is has "dual lines" and is not a double pumper like I had previously thought. My neighbor helped me adjust the fuel mixture, and tighten down the accelerator pump. Today I learned that the previous owner installed an electronic ignition, so I did not have to set the points. I just timed the motor to 14 degrees ADC and took her for a spin. I have to say - WHAT A DIFFERENCE There is so much more pep in her step! If I accelerate out of a turn. The car still stumbles when I step on the ignition, but compared to what I was dealing with before, its like night and day.

One thing I noticed though was that my vacuum advance no longer seems to be working. The only reason I think it isn't working anymore is because I disconnected the line prior to setting the timing, and after reconnecting, the timing mark does not advance. I am not positive, but I believe it was working a few weeks ago...

Do you have the vacuum advance can hose attached to stepped or manifold vacuum?
If you have hose attached to stepped source the vacuum advance will not move until you open the throttle, better to have the hose attached to manifold vacuum. Should have a port below the throttle plates to connect hose.