Back to back fox versus 94-95 TB dyno results inside!!!

[Black95GTS]

They forget to look at the rest of the package and goals of the end user.

True... here we are looking for maximum power.

Damn do we get long winded when we go back and forth.

If what you are saying is true, and I agree with you, wouldn't you want the larger TB, so that the pressure differential in front of the TB is extremely high compared to the extremely low pressure differential in the manifold, so that when the TB is opened, the pressure differential equalized with the most velocity possible? And if you can aid that velocity by additionally "necking down" the manifold, then why not?

Cool stuff!

Adam

 

[94v6GT]

Why in the world is this thread 5 pages long?!

Instead of accepting this info for what it was, we focused on what it wasnt.

Honestly SO WHAT if the TB's werent the same size? if they were , someone would say: "they werent the same brand!", or "if he used _____ intake the results would....." or "why doesnt the graph start at X rpm", "he didnt rev it high enough to show......." or " but if we saw datalogs then......." or"if it was tuned different...." , "well those heads dont benefit...." etc.

to me this dyno test DOESNT prove that 90m TBs are useless, or 65mm is more than adequate, or fox intakes flow better, or that SN95 intakes do well. All it proves to me is that:a fox intake w/ 75mm TB made "X" more power than a SN95 intake w/ 65mm did. Thats it!

{END RANT}

I like everyone volunteering useful information and contributing to tech knowledge here, but , why get so heated/longwinded over the easiest part on the motor to swap?


:SNSign:

 

[WhiteCobra95]

The issue here was in the title: "Fox vs. SN95 TB."

In reality the test was more of a 65mm vs. 75mm TB comparison. This information is very valuable, especially to me since the numbers have me thinking about a 70mm for my new engine combo instead of the 65mm I had planned.

I apologize if I offended you Paul. I was only responding to some of the conclusions being drawn from the results. I appreciate you sharing test data with us and using your hot rod to generate it.

- Mike

 

[Killercanary]

On a completely unrelated note, at what pressure are you driving those poor 24s and what duty cycle are they running? I'm guessing around 50PSI and near 95 percent.

Adam

Its been a while but I'm 99% sure that my base FP is set at 45lbs. Surprisingly, I never went above 88% duty cycle. Here's a screen shot of my datalog, the green center graph is the duty cylce, and there is a scale on the left side that shows the minimum and maximum. it also shows the rpm scale in red and the O2 readings at the bottom. This is the entire run from start to finish. Hopefully this will help some too.

 

[5spd GT]

True... here we are looking for maximum power.

Damn do we get long winded when we go back and forth.

If what you are saying is true, and I agree with you, wouldn't you want the larger TB, so that the pressure differential in front of the TB is extremely high compared to the extremely low pressure differential in the manifold, so that when the TB is opened, the pressure differential equalized with the most velocity possible? And if you can aid that velocity by additionally "necking down" the manifold, then why not?

Cool stuff!

Adam

I really enjoy our "going back and forth." I can not state it enough and I hope that no one person thinks that I am upset about anything. I really enjoy a nice debate that is sensible and grown-up, in which this is.

Now, about your question (in bold).

At wide open throttle, depending on the intake tubing size, the pressure differences will be quite similar in my opinion, with the most extreme differential being at the MCSA of the throttle body runner. I do not think there is any significant difference.

Now with the velocity in mind, there is no need for it because the air has to turn 180 degrees to hit the runners after the throttle body runner. In my conversation with a *custom cam grinder* over the phone, he told me that a particular person gained close to 2 MPH by modifying the intake tract and TB to be directly in front of the runners. Think about the throttle body being on the driver side and not the passenger side.

Without many details, I believe the throttle body helps fill the plenum in order to get the air ready to go down the chute.

Thanks for the "cool stuff" as well!

 

[Black95GTS]

Now with the velocity in mind, there is no need for it because the air has to turn 180 degrees to hit the runners after the throttle body runner. In my conversation with a *custom cam grinder* over the phone, he told me that a particular person gained close to 2 MPH by modifying the intake tract and TB to be directly in front of the runners.

Sounds like the recipe for an EFI Spider intake to me! How streetable is it though? I can't imagine it would play nice for street driving and would probably be a bear to tune.

Well... if velocity doesn't matter then I still maintain a "big" throttle body is where its at, and at the worst, it won't hurt anything.

Adam

 

[Black95GTS]

Why in the world is this thread 5 pages long?!

Instead of accepting this info for what it was, we focused on what it wasnt.

Honestly SO WHAT if the TB's werent the same size? if they were , someone would say: "they werent the same brand!", or "if he used _____ intake the results would....." or "why doesnt the graph start at X rpm", "he didnt rev it high enough to show......." or " but if we saw datalogs then......." or"if it was tuned different...." , "well those heads dont benefit...." etc.

to me this dyno test DOESNT prove that 90m TBs are useless, or 65mm is more than adequate, or fox intakes flow better, or that SN95 intakes do well. All it proves to me is that:a fox intake w/ 75mm TB made "X" more power than a SN95 intake w/ 65mm did. Thats it!

{END RANT}

I like everyone volunteering useful information and contributing to tech knowledge here, but , why get so heated/longwinded over the easiest part on the motor to swap?


:SNSign:

Easy solution for you is to not read the thread anymore. The topic is debated because a stock mustang makes 215 fwhp. An HCI mustang makes roughly 345. That means all this work is done for about 130 fwhp. If doing something as simple as ordering a different size throttle body can get you 5-10 horse power, its worth it. A 10 horse power difference is 7.5% of the power you are adding over stock. For no additional dollars! Every little bit helps when you are naturally aspirated.

Adam

 

[ProKiller]

there are some of us that are very interested in this debate and data. didn't your mother ever tell you if you don't have anything nice to say don't say anything.

Now to get back on topic...
Adam and Dave, you guys are debating an N/A motor. What say yee when you toss a blower into the mix?

 

[5spd GT]

I have not really thought about the blower side of things.

A few things that come to mind:

1. The throttle response will be exagerrated.
2. The throttle body does not need to be as large, because of the cramming effect.
3. The engine could still possibly want a larger throttle body for less restriction.

Adam - I have no problem with a larger throttle body whatsoever. I just believe it needs to be required.

By the way, that "2 MPH gain" I was talking about was on a track car, so I agree with your thoughts!

 

[Black95GTS]

there are some of us that are very interested in this debate and data. didn't your mother ever tell you if you don't have anything nice to say don't say anything.

Now to get back on topic...
Adam and Dave, you guys are debating an N/A motor. What say yee when you toss a blower into the mix?

I'm actually gonna agree with David here and say once you pressurize the intake, and intake manifold, to the point where boost develops, the throttle body size becomes somewhat moot. There are plenty of cars on TurboMustangs.com with 65mm Ford throttle bodies running 500 wheel horse power.

Adam

 

[ProKiller]

because of the less turns and the straighter shot into the intake, do you think the fox setup would do better for the velocity effect?

 

[Black95GTS]

because of the less turns and the straighter shot into the intake, do you think the fox setup would do better for the velocity effect?

I still don't buy that the fox intake is any better performance wise. It definitely looks better though. There is a mechanical issue in that the ramp rate of the throttle cable supposedly gives it better throttle response, but I've never experienced it first hand.

I attribute Fox swap results to 1 - Accufab makes the best throttle bodies and thats what most people swap to and 2 - when people make throttle body swaps they go to a bigger throttle body which would provide more throttle response regardless of SN95 or Fox.

I had the TFS elbow on my car and it looked pretty damn unrestrictive to me. I was talking to Paul about this in a nother thread and he did make a good point about the fixed elbow from the TFS does have a slight change in elevation as well as the angle. Not sure if thats a deal breaker though.

Adam

 

[greenlantern]

Yeah I am running the TFS elbow as well and it doesn't look to me to much of a restriction compared to others I have seen. I can see where some may say that the turn on the fox setup is smoother but compared to the trick flow piece I can't really see it being much.

 

[final5-0]

I still don't buy that the fox intake is any better performance wise. It definitely looks better though. There is a mechanical issue in that the ramp rate of the throttle cable supposedly gives it better throttle response, but I've never experienced it first hand.

I attribute Fox swap results to 1 - Accufab makes the best throttle bodies and thats what most people swap to and 2 - when people make throttle body swaps they go to a bigger throttle body which would provide more throttle response regardless of SN95 or Fox.

I had the TFS elbow on my car and it looked pretty damn unrestrictive to me. I was talking to Paul about this in a nother thread and he did make a good point about the fixed elbow from the TFS does have a slight change in elevation as well as the angle. Not sure if thats a deal breaker though.

Adam

Yeah I am running the TFS elbow as well and it doesn't look to me to much of a restriction compared to others I have seen. I can see where some may say that the turn on the fox setup is smoother but compared to the trick flow piece I can't really see it being much.

I'm running the Edelbrock elbow and compared to the TFS elbow, I'd have to
say it is very restrictive.

One of these days, I'm switching over to the TFS.

Grady

 

[T0rk3d]

Yep the edelbrock is 70mm compared to the TFS' 75mm.

 

[final5-0]

Yep the edelbrock is 70mm compared to the TFS' 75mm.

Yes the Edel is smaller but I see the design of how it is made as more of an
issue than its size

Or put differently ... if it was 75mm in size, I believe it would not flow as
freely as the design of the TFS elbow

Grady