Vacuum advance information and myths

RustyRatRod

I was born on a Monday. Not last Monday.
FABO Gold Member
Joined
Jun 7, 2010
Messages
91,781
Reaction score
79,229
Location
Georgia
Nice. I had a '90 MP engine book. Loved it. It's long gone now. I don't know who stole it
Keep an eye on Mancini's literature section. They sell the MP engine manuals CHEAP when they have them.
 

Ironracer

Gearhead
Joined
May 8, 2020
Messages
8,733
Reaction score
4,107
Location
Tampa Bay Florida
Keep an eye on Mancini's literature section. They sell the MP engine manuals CHEAP when they have them.
Right on Brother, Will Do! Thank You! Right now, I have Way more intense issues to deal with... like tryin' to keep my Address! And what hope I had for that is trashed, reversed and heading down the septic tank. I hate to say it but it's pay to play in Florida if you do not own the land that your home is on and you don't pay exactly what the people claim you owe they can do what's called a default judgment motion and get the judge to grant them possession of your home and get you out of it.... in 10 days. As long as they got a dirty *** lawyer with no morals. And no I'm not knocking lawyers..
 

Bewy

Well-Known Member
Joined
Jan 1, 2021
Messages
2,983
Reaction score
1,902
Location
Australia
There is a two part video on Unity Motor Sports you tube, on vac adv. D. Vizard appears in part one. Done about two years ago, sorry do not know how to link it. Before & after results/comments are provided, on a tunnel rammed Ford with two 660 Holleys! Worth watching.
I use a different method to set up MVA than shown in the video.
 

Rat Bastid

Dunamis Metron
Joined
Nov 23, 2020
Messages
2,942
Reaction score
3,014
Location
22 The Avenue
There are certain situations (very limited situations) where you can’t use VA on a street car.

Other than that, you need it.

And, if you NEED manifold vacuum at idle you don’t have enough compression, your cam is too big or both.

If that’s what you have then by all means do it. It’s cheaper than getting the compression up or changing cams or both.

IMO it’s better to build it right the first time.
 

TT5.9mag

Two atmospheres are better than one
Joined
May 5, 2016
Messages
3,429
Reaction score
3,732
Location
So cal
The biggest problem with VA (either ported or manifold) is the lack of willingness of the owner to understand what is happening and why, and the ability (knowledge and tuning time) it takes to get it right. It’s amazing to me how many people you meet at car functions, (race track, car show) who have no idea how to set basic timing or adjust a curve or don’t even know where their timing is. Me; “what’s the timing at?” Them; “don’t know haven’t even put a light on it yet.” Me; shakes head and walks away.
 

Bewy

Well-Known Member
Joined
Jan 1, 2021
Messages
2,983
Reaction score
1,902
Location
Australia
Yup,
VA is not understood. Not helped by ignorant magazine writers you talk about the 'feature' engine in their article, & mention the MSD or DUI dist they are using for free plug, but make no mention of VA.
 

TT5.9mag

Two atmospheres are better than one
Joined
May 5, 2016
Messages
3,429
Reaction score
3,732
Location
So cal
Yup,
VA is not understood. Not helped by ignorant magazine writers you talk about the 'feature' engine in their article, & mention the MSD or DUI dist they are using for free plug, but make no mention of VA.
That’s usually because they are writing a magazine article and the only number that matters is the peak number on a dyno. Almost never does the “magazine build” get stuffed in a car and re-tuned for the street
 
Top