Bigger TB, some interesting numbers...

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SuperHO

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why not a design stolen from BMW with individual throttle bodies fed by a common plenum? of course, theirs are electronically controlled, allowing for a quasi variable valve timing setup...i still gotta find another throttle body so i can play with that idea. i might've already figured out how to control both of them with the stock cable, but i gotta get one apart to see if it'll work.
 

illSHOyou

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Sorry to hijack but since were on the subject, I don't have a bench flow tester but I did some analysis in a CFD software when I was building my intake, the geometry is not exact because the software will not be able to analyze actual geometry but its close, it gives you an idea of where the velocity and pressure drops are

sho_intake_long_iso.gif

sho_intake_long_top.gif

sho_intake_long_press.gif


SHO_intake_iso.gif

SHO_intake_top.gif

SHO_intake_press_stag.gif


As you can see the stock intake is a good design but has a good amount of pressure drop which leans out the last cylinders, also the air is pulsating in the intake and the analysis only shows the velocity once its reached a constant flow, like a bench test would. Trial and error will get you in your desired powerband however for me, I copied the Boss 290 Aussie intake, here's a picture I found on the web, shown below on the left, and 2000 Cobra "R" 5.4L 4-valve on the right,

2000 cobra r intake

That diagram is awesome! It’s obviously that the air moving into the intake manifold in the beginning is extremely important to maintaining good velocity around the bend and into the plenums. Most likely knife edging this section could prove highly beneficial.

SHOMETHE$$$

Is it possible to show air conditions at different rpm/flow? 100, 150, 200, 250, 300 CFM?
Also could a smooth transition be added in the Y area of the model to reduce turbulence and increase velocity around the bend, once again modeled?

I don’t know how much time you got….? HeHeHe, evil laugh…

Maybe cut the Y section out and add two TB on the end of the plenum tanks, and model.

We could probably go all day lol…
 

Phoenix

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Less asking more doing please. Allthough I have no idea how much improvement I got from this , It certainly wont hurt with a ported intake and 40+. 75mm ftw.


DSC00811.JPG


DSC00585.JPG


DSC00581.JPG
 

illSHOyou

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Less asking more doing please. Allthough I have no idea how much improvement I got from this , It certainly wont hurt with a ported intake and 40+. 75mm ftw.


DSC00811.JPG


DSC00585.JPG


DSC00581.JPG

I was curious, why didn't you just weld the stock TB holes and re-drill? Is that particular TB pretty nice?
 

sho_sc

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Before you view the dyno sheet a couple of comments ...

1) This was an old dyno graph of my 3.0L before the new "better" changes.
2) The 2 graphs represent the same engine/fuel/tune, but with different intakes. Other than some internal intake changes that I don't want to discuss here, the Throttle Body was changed from the stocker to a 68mm.
3) I pull timing down to zero at 7450 RPM to save the impeller .. not really interested in getting big numbers on a dyno.

You can clearly see the improvement.

intake_change_2.jpg
 

illSHOyou

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Before you view the dyno sheet a couple of comments ...

1) This was an old dyno graph of my 3.0L before the new "better" changes.
2) The 2 graphs represent the same engine/fuel/tune, but with different intakes. Other than some internal intake changes that I don't want to discuss here, the Throttle Body was changed from the stocker to a 68mm.
3) I pull timing down to zero at 7450 RPM to save the impeller .. not really interested in getting big numbers on a dyno.

You can clearly see the improvement.

intake_change_2.jpg

We could conclude that a TB size improvement may not be noticeable on dyno for N/A, but could net a 1-2 hp increase throughout the curve. Much more improvement boosted however.
 

Phoenix

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I was curious, why didn't you just weld the stock TB holes and re-drill? Is that particular TB pretty nice?


This is a Roush BBK 75mm TB off a 4.6 (mustang) motor.

To weld , Then I would need to plane it? plus the TB is square while the intake is a weird shape , the bolts would arrive in a very thin place I believe.

The adaptor was kinda easy to make , a chunk of alu , rented a 3" holesaw bit for metal , and its just a matter of drilling in the right spots.
 

Phoenix

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I also had to bore the Intake inlet to match the bigger TB. Plus re-route all the vac and IAC lines. Plus the throttle cable is on the wrong side , Had to make a bracket for it.

DSC00586.JPG
 
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illSHOyou

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I also had to bore the Intake inlet to match the bigger TB. Plus re-route all the vac and IAC lines. Plus the throttle cable is on the wrong side , Had to make a bracket for it.

DSC00586.JPG

I am going to mess with some porting ideas behind the TB. I believe I can increase the hole to 75mm, but it gets awfully close to the idle air port.
 

tompumped

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Interesting discussion.
I'd be happy to have a 250 whp n/a SHO. I didn't know that could be possible with cams, intake mods, a tune, and a three inch exhaust. I thought you would have to build a high compression motor. I'm curious, is he running a dual 2.5" y pipe to three inch or dual three inch?
 

Phoenix

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Interesting discussion.
I'd be happy to have a 250 whp n/a SHO. I didn't know that could be possible with cams, intake mods, a tune, and a three inch exhaust. I thought you would have to build a high compression motor. I'm curious, is he running a dual 2.5" y pipe to three inch or dual three inch?

If your talking about me , its 2x 2.5 into one 3". 250hp is easily obtainable N/A without high comp.

Needless to said thats what I want to do this winter , high comp pistons...:swing:
 

warmonger

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mega squirt...probe guys use it all day to remove the vaf and use a gm map sensor
 

tompumped

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If your talking about me , its 2x 2.5 into one 3". 250hp is easily obtainable N/A without high comp.

Needless to said thats what I want to do this winter , high comp pistons...:swing:

On page one someone mentioned Lance, maybe that's you. I thought dual 2.5 y to 3 would be overkill. I was running that on my f body.
I'm guessing if I want to make power I have to learn how to tune my car. I wouldn't want to run a lpm, but I don't know much about it. I would end up saying why not install high compression pistons if i'm going to go through the trouble to tune my car. :evilgrin:
I need to start saving money or sell my other car.
I guess now that I think of it 300 shouldn't be hard to obtain, but I don't know anything about modding a sho. I have basic mods and a performance fuel pump. I'm thinking about trying nitrous for now.
 
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Phoenix

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Nope Lance aint me.

3" is way too big for a stock sho , but mine got every mods possible , except the pistons. As far as the tweecer , SHONUT is supposed to tune me in in a nearby future , i live like 2 hours away from him. Im a complete ******* with it , cant tune this for shit.
 

illSHOyou

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On page one someone mentioned Lance, maybe that's you. I thought dual 2.5 y to 3 would be overkill. I was running that on my f body.
I'm guessing if I want to make power I have to learn how to tune my car. I wouldn't want to run a lpm, but I don't know much about it. I would end up saying why not install high compression pistons if i'm going to go through the trouble to tune my car. :evilgrin:
I need to start saving money or sell my other car.
I guess now that I think of it 300 shouldn't be hard to obtain, but I don't know anything about modding a sho. I have basic mods and a performance fuel pump. I'm thinking about trying nitrous for now.

1. Its not easy
2. It takes the right combination of parts, know how, tuning

One thing you should notice, at least basic comparison. Regardless of 4cyl, 6cyl, 8cyl if the power plant is making say 300 hp, then its going to flow 300HP worth of cfm regardless of what engine type.

2.4L 4 cylinder N/A 300hp = 3inch exhaust
3.2L 6 cylinder N/A 300hp = 3inch exhaust
5.0L 8 cylinder N/A 300hp = 3inch exhuast

Not always the rule, but generally close. I like to point out only the meanest 4 cylinders require a 3 inch exhaust N/A.
 

tompumped

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I know it wouldn't be easy. I still have a lot to learn.
I know the sho motor is much different, but I have helped build a few high hp ohv v8 engines. I built one for myself that is reliable and powerful, but it's carbureted.
If I want to i'm sure I would be able to learn how to use the tweecer. As long as I had the patience.
I would take the time to do the proper research before spending the money. It wont be anytime soon, unfortunately.
Thanks for the info
I knew 3" would be overkill for a stock sho. I didn't know you would need an exhaust that big for 300 hp. I probably should be running 4" on my other car.
I wonder how much someone would charge to tune a car. I think he's like 8 hours away from me?
 
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