ST220 parts myths topic discussion thread

[BuckeyeSVT]

This thread is for discussing the Pinned Topic "ST220 parts myths topic". In order to keep pinned topics clean we will start having discussion threads below the pinned threads. This keeps the clutter to a minimum and allows more info to be discussed inside a clean area.

 

-Dom

[Nezerconezer]

Geez it makes my mondeo UIM sound pretty bad. I'll have to take it to a dyno to see if the curve is THAT bad. The engine certainly doesn't feel like it has that crazy torque curve.

[Rikenbomb]

Your torque curve will probably not follow the ST220 torque curve simply because of you installing the ST220 UIM manifold. What Dom is pointing out is that you probably didn't get any more gains from the ST220 manifold over the stock Taurus '04+ UIM. That and it's ALL in the tune.

[Terry Haines]

The exhaust is almost the same as the X Type Jag FWIW..

 

The story went like this. Ford of Europe accepted the 3.0 V6 used in the USA, as the engine for the ST220. What they didn't take was the calibration with it!

 

Ford of Europe(Uk) developed their own calibration for the EEC etc as none of those used on vehicles in the US that took the 3.0 V6 would meet their needs...simple as that. As Dom has shown before on a std Vs SVT 2.5, none of the major hardware,or SVT stickers, are needed to get the std 2.5 close to an SVT...we have been here before!!

[Speedmaster]

Here's what we know:

 

ST220 manifold = ~ $1400.00

Taurus manifold = ~ $ 150.00

 

Difference = $1250 = tune and exhaust and beer money

[Rikenbomb]

That intake costs $1400?

[Nezerconezer]

No I purchased mine off ebay for 236 shipped.

[rac74]

I had heard of a few people who spent $800-1000 on theirs new or lightly used and know of one who spent much more than that!

Edited May 2, 2010 by rac74

[TRicker]

guys, it has also already been proven that the ST220 engine itself is the same. any 3.0 mondeo has that same intake manifold setup. it is NOT ST220 specific, the part numbers are the same. the changes between the two is in the exhaust, and the airbox setup. that and tuning, is about it.

 

 

and terry i must disagree on making a stock 2.5 "close" to a SVT. the manifolds are completely different in size, and the cams are different. this is NOT the case between 3.0 mondeo engines and ST220 engines though.

[Terry Haines]

My point on the issue was calibration. Dom has show from dyno etc that a non SVT 2.5 can make close to an SVT unit with just injectors and calibration and none of the fancy SVT 'sticker' hardware..The point I was making is that the calaibration, not hardware, is the major factor..

[Slow Cat]

The Mondeo intake has a larger internal volume and tapered runners. Ford has said the Mondeo intake flows better than the US counterpart.

 

What has NEVER been proven with whether the increased intake flow (and likely velocity, due to the tapered runners) is useful. No one has done a back to back tuned comparison.

[Terry Haines]

That is just sales blurb.

Every 'oval port' V6, Ford,Jag etc etc.that has a plastic lim has a taper in the runner!!

[Nezerconezer]

The taper isn't visible from the outside on the plastic UIMs at least not on the 04/05 taurus. The St220 manifold taper is really noticable.

[Slow Cat]

That is just sales blurb.

Every 'oval port' V6, Ford,Jag etc etc.that has a plastic lim has a taper in the runner!!

 

How much of a Taper? I understand you have more inside knowledge than most and mean no disrespect, but you have said that before and have yet to give numbers or proof.

 

From the outside of the runners on my 04/05 there is no noticeable taper. ( I don't feel like cutting open the intake on my car to measure)

The 03 and earlier intakes I've seen have no noticeable taper.

Talking about intakes that can't be used on our cars (Jag, Lincoln, etc.) seems like a moot point.

 

Maybe there is a slight or internal taper, but again my question is HOW MUCH?

 

Here is what I have measured -

 

• The cross sectional area of the Mondeo intake runner drops by ~30% along it's length, which should cause a corresponding increase in intake velocity.
  
• The port width drops just over 3/4" from just inside the plenum to where it meets the lower intake.
  
• Compared to the 04/05 intake the Mondeo intake plenum has slightly greater internal volume, also each runner has a considerably larger volume.
  

Now whether the intake itself is worthwhile is debatable but remember... "You can't f*ck with the physics" and everything I've heard tells me that Greater velocity + Greater volume = Greater potential

 

The Mondeo intake has the math behind it to support higher flow and greater velocity leading up to the intake port. If you have proof otherwise I am open to hear it, but blowing off the numbers and theory is not the how I thought things were done around here.

Edited May 6, 2010 by Slow Cat

[Terry Haines]

Example, an LS 3.0 LIM oval port is 59 mm wide and tapers down to 57.6 MM at the head face..

[Terry Haines]

I don't have a spare UIM to cut up..but I know most all the oval port induction systems have a progressive taper from the LIM plenums down to the face on the head...BTW..don't SHOUT at me!!

[rac74]

Slow Cat,

 

Perhaps thinking of taper as gradual reduction in area (call it a 'reduction ratio') as opposed to the more traditional sense as most of the manifolds I've looked at don't have a consistent shape from plenum to head, hence no visible taper (some are 'rounder' at the plenum). They do 'taper' or reduce in area though. By how much, I wouldn't know without cutting one up.

 

One thing about the use of gradual port reduction is flow quality. It's difficult to maintain high velocity in a duct without getting separation from the wall which acts to choke the port, limiting its effective area. So engines with a higher mass flow might benefit from increased taper angle, 'reduction ratio', etc... Taper itself (as I understand it) doesn't create more velocity, it is a tool for managing flow quality (among other things).

[Terry Haines]

..look at it with distance in mind. I gental taper will increase velocity but over a distance Re say a long taper nozzle on your hose pipe..For quick velocity increase then a venturi is used..over a short distance as in say the area just into the port from just behind the valve seat..this gives gases a quick boost into the chamber..grind it away any the venturi effect is lost...

[Slow Cat]

Terry,

 

Sorry for the caps, was more for emphasis than a shout. The LIM may taper on all of the engines, I'll take your word for it. I was only refering to the upper intake manifold in my post.

 

With the stock setup lets say there is a taper the last 5 inches or so before the port (complete geuss on distance). But the upper intake feeding down to the LIM has no taper, at least from what I can see. So a majority of the air column in the runner has a consistent speed, and gets a bump just before entering the head. What I was trying to point out was the the Mondeo upper intake has a large reduction following it's entire lenth. It ends up the same size as the stock upper intake, but the runner starts out a fair bit larger. So the entire air column is accelerating along the entire length of the runner, rather than just before entering the head. From what I've read this should help increase the velocity of the air as it enters the head since the column behind it should have accelerated more than it would with the stock upper intake. This faster, larger column of air should translate to more inertia forcing air past the valve, even as it starts to close.

 

rac74,

 

I am just estimating the 04/05 upper intake based on the external size of the runners since I don't want to cut up the intake on my car. The interior of the runners may change shape and size, but because of the wall thickness there doesn't seem like much to work with. I could be wrong.

 

You are right, the taper itself doesn't increase velocity, it is the interaction of the taper with the forces creating the flow. Pressure, velocity, and area are all directly linked to each other IE (p₁v₁=p₂v₂ or a₁v₁=a₂v₂). If the pressure drop from the throttle body to the intake port remains constant while area decreases then the velocity must increase to maintain equal flow. In a perfect world the velocity would increase by the same percentage the area decreases. In the real world, on an engine, there will be losses. Such as flow seperation, restrictions, etc. On flow seperation, the Mondeo upper intake is aluminum and fairly rough on the inside, from what I have read this should help to decrease the total amount of air the seperates causing the restriction you mentioned.

 

 

 

There is no testing or proof one way or the other, but as I said before Greater velocity + Greater volume = Greater potential, and based on my reading and understanding the mondeo upper intake should be able to deliver on both. If I am wrong so be it, I have been wrong in the past.

[BuckeyeSVT]

Chris,

 

If you want a spare 04/05 manifold to disect or cut in half... Let me know. I've got plenty of spares... I'll toss one out for scientific purposes... Lol.

 

-Dom

[Slow Cat]

Chris,

 

If you want a spare 04/05 manifold to disect or cut in half... Let me know. I've got plenty of spares... I'll toss one out for scientific purposes... Lol.

 

-Dom

 

I'm beyond broke right now. Saving for the wedding, and waiting on school loans. If I get my ducks in a row I'm hoping to get a new exhaust and a real CAI on the cougar, then bring it back to you for tuning. We could settle the whole debate on the Mondeo intake since I have everything but hood clearance taken care of.... If I close the hood you can feel a slight bump where the intake pushes up.

[rac74]

How much cam cover clearance have you now?

[BuckeyeSVT]

I meant for free... You'd have to pick it up ... But free

 

-Dom.

[Slow Cat]

How much cam cover clearance have you now?

 

Cam cover there is lots of room, I cut off the tab on the back of the UIM that hit the cam covers the first time I test fit it. The COP units with the 04/05 valve covers is what caused my frustration, that and wanting to keep the EGR. From what I've read if I had dropped the COP units I could have gotten away with a smaller spacer, or if I had switched to the older cam covers things would have been easier.

 

 

I meant for free... You'd have to pick it up ... But free

 

-Dom.

 

Hmmm ... I'll talk to Tabitha about it, we'll be in Cleveland next weekend I think so maybe I can swing by.

[TRicker]

so in this taper discussion, i come up with the question. "where" in the powerband does this taper (increase in velocity) take effectiveness? i have been reading a bit on airflow and such like mentioned before but i can't really get any good information on the advantages of tapered runners.