Anyone want to discuss throttle bodies? Is bigger better?

butter makes the popcorn soggy. i like the machine made butter flavored popcorn the best.

there is not nearly enough drama in this thread; my popcorn is getting stale.

for my $.02, the throttle body should be able to flow more than the engine can possibly use, because it is probably not 100% efficient and i wouldn't want it to be a possible restriction. at the same time, a throttle body that flows way more than the engine could ever hope to use does no good.

so in my case, with a 410 and a max rpm of 6000, a 75 is correct, because it easily flows more than the 712 my motor will be able to use, but not so much that 1/2 throttle is effectively WOT as far as my motor's needs are concerned. if we believe accufab's information that a 90mm throttle body flows 1369 cfm, then that is almost twice as much as my needs of closer to 700 cfm, so about 1/2 throttle on a 90mm would be giving my motor all the air it can handle.
 
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Actually the HUGE restriction in that setup was the Edelbrock 94-95 style intake adapter. It definitely was not designed very well.

It's been several years since I did the swap and don't remember for sure.


It was the same combo and both setups were run after winter refreshes on the same motor.

Yeah I could see that adapter being the restriciton, one of the reasons that fox tb swap is :nice:

I was just trying to figure out how you gained a potential '4 mph' in such a short time with just those changes. Either way, nice gain.

...............

The difference between 0 miles and 2,000 miles on a new engine is much different than 98,000 to 100,000 miles when it comes to freeing up horsepower.

Black95GTS - If you say so.

BlackVert - I believe you have it right:nice:

tjh566 - 5spd or AODE, if you let in 'more air' than the pcm/ecu is used to seeing at the same throttle body voltage (tps), it is going to mix things up a bit. It will let more air in with less pedal on the gas and can make it jumpy and not so linear. Wide open throttle performance will be the same though.

If anyone has gains from bigger throttle body's post them up, and will go thru the 'top reasons why gains are seen'.

Thanks for keeping it dramaless.
 
http://forums.stangnet.com/showthread.php?t=583402

http://forums.stangnet.com/showthread.php?t=579407

Power gain and ET dropping, on an HCI 302 after switching to a 75mm TB. I don't understand how gaining power and dropping time is bad. Whatever your theory is, the guy switched from a stock unit to a 75mm unit and gained HP.

I have yet to see a dyno where someone dropped TB size and gained more HP. The only argument that I think you have is driveability, and like I said before that doesn't hold water for me as you should expect to have to tune your car for max power.

Adam
 
Too many variables at track in my o. Any bonehead that calls people Dyno "Queens" is a Track "biotch," lol.

In case I need to repeat, dyno tells all on same car. More power in the same car on the dyno means better ET's hands down with the right setup.
 
http://forums.stangnet.com/showthread.php?t=583402

http://forums.stangnet.com/showthread.php?t=579407

Power gain and ET dropping, on an HCI 302 after switching to a 75mm TB. I don't understand how gaining power and dropping time is bad. Whatever your theory is, the guy switched from a stock unit to a 75mm unit and gained HP.

I have yet to see a dyno where someone dropped TB size and gained more HP. The only argument that I think you have is driveability, and like I said before that doesn't hold water for me as you should expect to have to tune your car for max power.

Adam


I apoligize adam but you are getting things mixed up.

Noone said that you gain by putting a smaller throttle body on. You must be reading another thread.

Also the links you provided were going from a STOCK throttle body to a bigger one. Who is to say that a 65 or 70 wouldn't do it?

Also he dynoed different days/temps/port matching was done/etc.

The track has WAY to many VARIABLES. I'm sorry.

That did not prove anything.

The 65 or 70 would do the same thing.

Sometimes we got to look past our own bias...and the obvious.

No theory here, just facts.

Thanks for replying though, atleast you are trying and have a somewhat argument.

:nice:

Pokageek - Right on yet again...

As 94LaserRTC said - ALL other factors were EXACTLY consistent? (driving skills, track conditions, weather, amt of air in tires/fuel in tank, etc?):)
 
You guys must be in a dyno racing league. How much does that cost? How do you measure reaction time?

I guess you'll never be satisfied until someone acquires a stock, 65mm, 70mm, 75mm, and 75mm race TB and dynos them all back to back on the same day. Since that would cost a lot of money for no appreciable gain it will never happen. Unless someone at an R and D place steps up.

I'll just be over here with the people who's cars go faster on the road and don't care about the rollers.

Adam
 
Black95GTS - A buddy of mine on this site (he will remain nameless) and he is very prominent over in the 5.0 Tech section, or was has seen this very test. He said on all, 65-75 throttle body there was a difference of 1hp or less across the board. Basically negligeble.

What we mean by the dyno is that there are SO many less factors that come into play to see if one part gave a particular gain.

Thanks for keeping it civil bud:nice:
 
I can see three things at work here :D

1) Track
2) Dyno
3) Drivability

For Sure 1 & 2 are all about WOT :)

I can see how a bigger tb could produce more WOT power :nice:

My gut tells me ........
There is gonna be a point where any bigger yields no more gains :shrug:
or
Any bigger yields very small gains :(

Now ... If larger in size does in fact contribute to drivability issues ......

It seems to me ....... you would just find a happy medium between
the two ... that is ... if drivability issues might be something that
would bother you.

Some are more critical about Street Conditions than others :shrug:

For Now ... I'm running one of the Ford 65mm tb's on my combo
with the elbow setup :)

One of these days ... I might go bigger to see what happens :D

Grady
 
I have a basic Question that ... IMHO ... pertains to this thread :D

I run the elbow setup

Does that mean no tb other than OEM and Ford's 65mm tb will be
compatible with the elbow setup :shrug:

btw ... I agree with the poster above about the Edelbrock Elbow :nice:

The worst of em all for aif flow :notnice:

When I get back in the modding game .....

My first mod is gonna be to move to a TFS Elbow :)

Grady
 
I have a basic Question that ... IMHO ... pertains to this thread :D

I run the elbow setup

Does that mean no tb other than OEM and Ford's 65mm tb will be
compatible with the elbow setup :shrug:

btw ... I agree with the poster above about the Edelbrock Elbow :nice:

The worst of em all for aif flow :notnice:

When I get back in the modding game .....

My first mod is gonna be to move to a TFS Elbow :)

Grady


As I stated my combo only flowed around 525 with a ported elbow matched to my Victor intake and a 75MM throttle body. I don't think it's going ot make much of a differance what you use for a throttle body because that elbow is so restrictive. I worked on my elbow for quite a while and tried to open it up as much as possiable but it was just not made to flow large amounts of air.
 
As I stated my combo only flowed around 525 with a ported elbow matched to my Victor intake and a 75MM throttle body. I don't think it's going ot make much of a differance what you use for a throttle body because that elbow is so restrictive. I worked on my elbow for quite a while and tried to open it up as much as possiable but it was just not made to flow large amounts of air.

I must have missed it. How are you able to test the flow of your own TB setup and how is it measured? Do you have a machine or something and at what physical point are you placing the sensor? Thx.
 
GOOD THREAD!!!

I have a 80mm (bought with car) and I was going to put a 90mm on just because I keep reading about 90mm on supercharged 400+ cube strokers. According to the flow of a 80mm 1142cfm should be plenty. If I get a 90mm I will dyno it and tell you the difference.
I remember old articles from the mid to late 90's where they tested TB'S and the 65mm on a stock or mild 302 worked very well, very close to a 70mm if not beating it.
Do they even make 65mm ones for 4.6l? I don't think Ford Racing does? All I ever see is 70mm and thats for 21 less cubes. Strange Ford makes a 65mm for a 302 and a 70mm for a 281?:shrug:
 
I must have missed it. How are you able to test the flow of your own TB setup and how is it measured? Do you have a machine or something and at what physical point are you placing the sensor? Thx.

We made an adapter for the flow bench at our local machine shop. We tested both setups. We did the 75mm BBK THB, Edelbrock elbow, MAC cold air kit, and 75mm Pro-m mass air. As a complete assy it flowed right around 525 cfm. We then flowed the fox conversion that was a 90mm accufab, AFM power pipe, 80mm shorty Pro-m. That combo flowed around 950 cfms. Tests were done a 28". We flowed just the throttle bodies and adapters too without the intake tubes and airflow meters. I don't remember the exact flow numbers. It's been several years since we tested them. I do remember that the 90mm accufab THB maxed out the flow bench. Another interesting fact we found was the assemblies flowed better with the air filters than without.
 
We made an adapter for the flow bench at our local machine shop. We tested both setups. We did the 75mm BBK THB, Edelbrock elbow, MAC cold air kit, and 75mm Pro-m mass air. As a complete assy it flowed right around 525 cfm. We then flowed the fox conversion that was a 90mm accufab, AFM power pipe, 80mm shorty Pro-m. That combo flowed around 950 cfms. Tests were done a 28". We flowed just the throttle bodies and adapters too without the intake tubes and airflow meters. I don't remember the exact flow numbers. It's been several years since we tested them. I do remember that the 90mm accufab THB maxed out the flow bench. Another interesting fact we found was the assemblies flowed better with the air filters than without.

See ... Thats the thing in all these ... TB Size ... Fox Conversion threads

No doubt you gained with larger pipe, tb, and meter

No one is gonna test just one change at a time because you usually
do an upgrade similar to what you did with several changes.

I just can't see the NA flow advantage of the Fox Conversion

The close to 90 degree bend on the Fox Conversion looks more
restrictive than the SN Elbow setup to me.

btw ... anybody got the answer to my Q above :D

Grady