David Freiburger latest video tuning a Holley

[skep419]

Curious how it would have turned out if he was able to tune WOT via power valve channel.

 

[mopowers]

I'm in the middle of tuning the same carb on my 340. My experience is similar to his - it's WAY fat out of the box everywhere in the curve.

Where I'm starting is drilling and tapping the idle feed restrictors, transfer slot restrictors, and power valve channel restrictors. I feel like he would've done himself some favors doing the same. Sounds like it still ended up running way rich.

I also noticed he prefers manifold vacuum for vacuum advance. I wonder what the group here thinks about that.

 

[skep419]

I'm in the middle of tuning the same carb on my 340. My experience is similar to his - it's WAY fat out of the box everywhere in the curve.

Where I'm starting is drilling and tapping the idle feed restrictors, transfer slot restrictors, and power valve channel restrictors. I feel like he would've done himself some favors doing the same. Sounds like it still ended up running way rich.

I also noticed he prefers manifold vacuum for vacuum advance. I wonder what the group here thinks about that.

Now you've gone and done it hahahaha. Ported vacuum for the win

 

[Bewy]

If DF prefers man vac adv, then he is a veeeeeeeeeeeeeeeery smart fella. So are these guys....

Note: at idle speed. If you do 'something' [ fuel or air ] & rpm increases, the engine is making more hp from that change. The engine liked it...

 

[Kern Dog]

After watching Roadkill and other shows with him, I wouldn't go so far as to call him a "Very smart man".
He is no dummy but something like manifold vacuum isn't enough to consider him any smarter than anyone else.
In the video, I thought that he mentioned that the manifold vacuum allows him to have base timing near 5 degrees and total near 35? From there the manifold vacuum puts him around 30 degrees at idle?
Why not shorten the slots and run it at 18-20 initial, 35 total? Or, lock out the timing at 35.
The debate for and against manifold vacuum is always a 10 page thread if not more.
I don't like the idea of it. You crack the throttle and suddenly all the timing goes away. Just weld up the slots or use the FBO plate...

....then let ported vacuum do it's job as intended.

 

[Icetech]

I am looking at replacing my carb right now and am leaning to a AVS2.. car is just a beater and i have never had a bad time with a AVS.. Which do you guys find easier to setup just for a daily driver the holley or avs type? I have had holleys work fine for years but never tuned them beyond jets and powervalves..

 

[66 Sat]

After watching Roadkill and other shows with him, I wouldn't go so far as to call him a "Very smart man".
He is no dummy but something like manifold vacuum isn't enough to consider him any smarter than anyone else.
In the video, I thought that he mentioned that the manifold vacuum allows him to have base timing near 5 degrees and total near 35? From there the manifold vacuum puts him around 30 degrees at idle?
Why not shorten the slots and run it at 18-20 initial, 35 total? Or, lock out the timing at 35.
The debate for and against manifold vacuum is always a 10 page thread if not more.
I don't like the idea of it. You crack the throttle and suddenly all the timing goes away. Just weld up the slots or use the FBO plate...

View attachment 1716460373

....then let ported vacuum do it's job as intended.

The timing doesn't "go away" when you crack the throttle. Yes it reduces from how much you had at idle, but only to how much you would have with ported e.g.
Manifold V/A
800 rpm - 30 degrees
1200 rpm - 25 degrees

Ported V/A
800 rpm - 0 degrees
1200 rpm - 25 degrees

I've made up the above figures to illustrate the point. I've been running MVA for a while now - the car responds exactly the same when the throttle is cracked open, partially or fully. The benefit I've seen is a cleaner idle.

 

[mbaird]

I am looking at replacing my carb right now and am leaning to a AVS2.. car is just a beater and i have never had a bad time with a AVS.. Which do you guys find easier to setup just for a daily driver the holley or avs type? I have had holleys work fine for years but never tuned them beyond jets and powervalves..

I run an AVS2 800 on my Barracuda and I find them to be difficult to fine tune despite what most people say. Too many interelated or hidden parts . What I mean is the rods are only available in so many configurations and the bleeds are fixed and/or hidden deep inside the carb body. Whereas a Holley has separate circuits and can be had with replaceable bleeds etc.

 

[Icetech]

I run an AVS2 800 on my Barracuda and I find them to be difficult to fine tune despite what most people say. Too many interelated or hidden parts . What I mean is the rods are only available in so many configurations and the bleeds are fixed and/or hidden deep inside the carb body. Whereas a Holley has separate circuits and can be had with replaceable bleeds etc.

well pewp.. i also like that the avs is $200+ less

 

[mbaird]

well pewp.. i also like that the avs is $200+ less

And avs2s can be had pretty cheap used ! Probably because many find them hard to tune. Or confusing.
That being said I have a stack of Carter/Edelbrocks I play with to force myself to learn them .
Haven’t mastered them yet but I am getting more familiar .
Just maintain a big supply of those little spring clips for when they boing into oblivion! Lol

 

[Icetech]

And avs2s can be had pretty cheap used ! Probably because many find them hard to tune. Or confusing.
That being said I have a stack of Carter/Edelbrocks I play with to force myself to learn them .
Haven’t mastered them yet but I am getting more familiar .
Just maintain a big supply of those little spring clips for when they boing into oblivion! Lol

haha i have a tray of like 300 assorted sizes already.. i have a street demon which you have to take the choke rod off to change metering springs and they are tiny and disappear

 

[skep419]

After watching Roadkill and other shows with him, I wouldn't go so far as to call him a "Very smart man".
He is no dummy but something like manifold vacuum isn't enough to consider him any smarter than anyone else.
In the video, I thought that he mentioned that the manifold vacuum allows him to have base timing near 5 degrees and total near 35? From there the manifold vacuum puts him around 30 degrees at idle?
Why not shorten the slots and run it at 18-20 initial, 35 total? Or, lock out the timing at 35.
The debate for and against manifold vacuum is always a 10 page thread if not more.
I don't like the idea of it. You crack the throttle and suddenly all the timing goes away. Just weld up the slots or use the FBO plate...

View attachment 1716460373

....then let ported vacuum do it's job as intended.

you’re correct, he said there’s too much mechanical advance to add any initial timing. He didn’t want to take the distributor apart so he hooked the vcan to manifold vacuum. More of a bandaid short term fix.

 

[1MeanA]

I am looking at replacing my carb right now and am leaning to a AVS2.. car is just a beater and i have never had a bad time with a AVS.. Which do you guys find easier to setup just for a daily driver the holley or avs type? I have had holleys work fine for years but never tuned them beyond jets and powervalves..

I've got a bit of time with my AVS2 and other similar design carbs and I like the tunability and ease of swapping rods and springs. A jet change is as deep as I want to go. If you have the right carb should you really have to go deeper? I really don't want to get into drilling and tap holes.

ps Just yesterday I pulled the rod and pistons out and swapped rods without taking the spring clip off....just put my finger on top of the piston to hold it on.

 

[skep419]

 

[mopowers]

After watching Roadkill and other shows with him, I wouldn't go so far as to call him a "Very smart man".
He is no dummy but something like manifold vacuum isn't enough to consider him any smarter than anyone else.
In the video, I thought that he mentioned that the manifold vacuum allows him to have base timing near 5 degrees and total near 35? From there the manifold vacuum puts him around 30 degrees at idle?
Why not shorten the slots and run it at 18-20 initial, 35 total? Or, lock out the timing at 35.
The debate for and against manifold vacuum is always a 10 page thread if not more.
I don't like the idea of it. You crack the throttle and suddenly all the timing goes away. Just weld up the slots or use the FBO plate...

I took it as he was just being lazy and didn't want to get into the distributor. The whole thing seemed a little half-assed to me.

 

[Icetech]

I took it as he was just being lazy and didn't want to get into the distributor. The whole thing seemed a little half-assed to me.

Most of his stuff is... i kinda stopped watching.. i don't get why he needs to get new shitboxes constantly when he has like 40 he could be making better

 

[AMC Diplomat]

Most of his stuff is... i kinda stopped watching.. i don't get why he needs to get new shitboxes constantly when he has like 40 he could be making better

Because his viewership would drop if he worked on the same car every week.

He stumbled across a money making concept with mass appeal that dozens of people now copy: working on a different thing ever episode appeals to enthusiasts across the automotive world.

Also, what's wrong with owning a fleet of shitboxes and getting people to buy t shirts to pay for it all?

 

[Icetech]

Because his viewership would drop if he worked on the same car every week.

He stumbled across a money making concept with mass appeal that dozens of people now copy: working on a different thing ever episode appeals to enthusiasts across the automotive world.

Also, what's wrong with owning a fleet of shitboxes and getting people to buy t shirts to pay for it all?

K... i phrased that badly.. i 100% get why he does it... it's a money maker, I would prefer to see things get fixed or rebuilt though and not just bought, put on tires and get running then forgotten

 

[Icetech]

BTW, i like David and what he has done for old cars and getting people into it.. guess i had enough of roadkill type stuff.. Like the Rotsun... they could have spent a few hours and made the car so much nicer without spending much, like a door latch.. little things

 

[AMC Diplomat]

K... i phrased that badly.. i 100% get why he does it... it's a money maker, I would prefer to see things get fixed or rebuilt though and not just bought, put on tires and get running then forgotten

Oh I agree. I could sit through a whole series in the winter when it's too damn cold to be under a car. But one thing I've realized is the audience who will sit through a whole series like that isn't that big.

 

[Icetech]

Oh I agree. I could sit through a whole series in the winter when it's too damn cold to be under a car. But one thing I've realized is the audience who will sit through a whole series like that isn't that big.

True... i tend to watch guys like Fitzee or Cold war motors that try to fix stuff and make it better.. (fitzee dragged me back into this stuff).. but if i were DF i would follow the cash too