Now that I have my new air box top and my 7 breaths better I can hear a new sound when I go over 4000 rpms. Is this due to the vacume advance? It seems like I get more power too?

I'm addicted...I just keep going through the gears 1st 4000 rpms :-) 2nd 4000 rpms :-) 3rd 4000 rpms 4th....look for cops...4000 rpms....5th.........look for cops....chicken out :-(

-Adam

 

perhaps you can hear your secondaries opening better? i do it while i'm under the hood all the time.. i got a breather box that i chopped the sides off of. more air, though it's hot air from the engine/radiator fan.

 

Yeap, you're hearing the secondaries opening. They open just before 4k rpm when vacuum operated, and yes your car will have more power then.

Do you shift at 4k rpm or is 4k the rpm right after you shift? I hope is the latter.

 

"Do you shift at 4k rpm or is 4k the rpm right after you shift? I hope is the latter."

cdrad51, I'm not sure what you mean. During my little "test drive." I wasn't shifting until after I passed 4000 rpm. Sometimes 5k sometimes 6k. I didn't mean to say I was shifting right at 4000 rpm. Oops!

<caveman speak>
Me like secondaries. Me know what they are. Just not know what new sound is. Now me know. Tanks.
</caveman speak>

Yes my car still has vacum operated secondaries. I guess I just didn't realize that that would cause the noise.

Would I hear the same sound if I mashed on the pedal at 2000 rpm? It probably wouldn't sound exactly the same due to the lower rpm.

I think I'm over analyzing....sorry.

-Adam

 

whast the difference?

 

dp

im so ashamed

 

Difference of what? Vacuum and mechanical secondaries?

Ill tell you what! I have mechanical secondaries and when i have no air box on, it sounds sweet when they open. I cant really explain the sound

 

"Do you shift at 4k rpm or is 4k the rpm right after you shift? I hope is the latter."

why do you hope its the latter?

 

Because to be at 4k rpm after shifting you have to roughly take it over 6k rpm before shifting, thus getting maximum power. That's basically the way to shift if you're racing, but of course not if you're driving normally. Then it's fine to shift at 4k rpm.

 

With your setup I be it does. Why do you have a 15 psi fuel pump? what FPR do you use?

 

I have a holley 1-4 psi reg.

 

and why did you choose the 15 psi pump over the 8 one?

 

sterling said he thought he had a 14 psi. so i just got the 15. Actually, i think mines a 16 psi.

Its loud as crap!

 

Oh...I see what you mean about the shifting. I wasn't referring to shifting while racing. Gotcha.

So anybody want to describe how the whole process works? Here's some questions. Assuming all emissions are in tact and the secondaries are vacum operated...you know stock configuration.

When do the secondaries open?

They don't open if you are just sitting in your driveway and you rev the engine right?

They do if you are going down the road and you mash on the pedal right?

What if you are accelerating, but, the pedal is only 1/4 of the way down? When you get to 4000 rpm do the secondaries open no matter what? That's what it seems like.

Soooo, how far do they open and when? Maybe I just need to read an FAQ someplace or a book. (I feel like this is an Auto Mechanics 101 question...sorry about that.)