1971 Firebird Build ("The Other Woman", a.k.a. Project "T.O.W.")

[carbuff]

So when last I wrote, Kevin was graciously attempting to help me with my shaker issue. Since that time, Eric and I have seemingly hit road block after road block trying to get this car to the point of taking a first test drive. It's not anyone's fault, it's just the nature of tying up loose ends...

I'll split these posts up so as not to write a novel!

First, on the shaker... I've now purchased 3 different shaker bases to try and find one that will work on my car, or at least one that we could easily modify to work. The WFO wasn't even close... The drop just wasn't nearly enough, and even if we dropped it more, the side wall height wasn't tall enough to raise the shaker enough. So that one was ruled out quickly (I had already taken the chance and ordered it, so that ones on me).

Next I ordered the PTFB 2" tall unit. This one drops 2" from the carb flange, then the side height is 2", bringing it basically back level at the shaker ring mount. This one was low enough, but we discovered that the filter is too tall inside this unit, and it hits my early-style shaker. I could perhaps get a shorter filter, but I'm already worried about having enough airflow through this thing.

So I called PTFB back up and ordered the 2.5" tall unit. With this one, we were able to position the shaker where we needed it height-wise! When we did, we realized that we needed to angle it relative to the carb flange for it to sit better relative to the hood (the original Pontiac intake manifold was milled at an angle to handle this under the carb). Thankfully the PTFB base had enough material to allow us to angle grind the ring where it sits on the throttle body to achieve the angle we needed.

But the next issue (which I also knew we had) was that the engine sits closer to the firewall, so the shaker was touching the hood opening when we closed the hood. So Eric cut out the base and moved the base 3/4" foreward relative to the throttle body. This puts the filter really close to the side wall of the shaker base in the back, but gets the shaker where we needed it.

Once done, the next problem is the opening between the shaker itself and the filter lid. There's maybe 3/8" opening all the way around the lid to the shaker! There's no way that's going to be enough air to feed this engine. After much deliberation, we decided that we had to cut holes into the shaker base. Unfortunately, there's not a good way to do this with a dimple die, so we just cut round holes. 25 of them to be exact, spaced at 2" around the circumference. That will pull in air from the engine compartment, but hot air is better than no air at all.

I had also decided to try using one of the K&N X-Stream filter lids. I've read mixed opinions on them, but again, non-optimal air flow is better than no air flow. :\ Unfortunately, after I overnighted one to test it last night, I discovered tonight that it's not going to fit. It hits the shaker base AND the shaker. Just not going to work...

In the end, I've come to the conclusion that I will probably have to remove the shaker and use a standard air filter for track events when I care about making max power. I just don't think there's going to be enough available air flow otherwise. However, what I will do is try all of the different combinations on a chassis dyno to see what the difference between them is.

So after all of that, here is a picture of the final product. I'm taking it to be powder coated tomorrow to clean is up. I haven't decided on the color yet, but it will be black or grey...



And the hood/shaker: