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Port/Polish intake manifolds?

M

Mac

CEG'er
Joined
Nov 7, 2009
Messages
179
Location
Highlands Ranch, Colorado
i've heard of people doing this on the 2.5L, but i've tried searching for more info with no luck..

i'm trying to figure out if really what i would be doing is port MATCHING for a more accurate fitment? or if it's really enlarging the whole port on the LIM and just port matching the UIM to that?

also i've heard some positive and some negative info about Polishing the manifolds as well as the TB... some people say that the textured roughness on the UIM and TB shouldn't be smoothed out, something to do with the way the air passes by it? any insight on that?

ans lastly, if i were to enlarge the primary LIM ports only, and port match the UIM to it would that cause any problems? i'm thinking that since the 2.5L doesn't need the top end help, that doing this would help out a little bit on the lower end... any thoughts would be appreciated!
this might be a totally bad idea but i'm just curious...


thanks, Drew
 
Mac said:
i'm trying to figure out if really what i would be doing is port MATCHING for a more accurate fitment? or if it's really enlarging the whole port on the LIM and just port matching the UIM to that?
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I wouldn't recommend doing a port match setup on a stock csvt. First of all you have no guides to follow. You can do this very process. If you wish can cover that. But it's not 5 min write up.
As the uim plenums change to smaller runners, the runners are tapered. This allows the air to travel quick at lower speeds and obviously higher speeds once the LIM secondaries open. Now the tapering is needed especially since the 2.5L is not a heavy breather!! So port matching them is not what i would recommend on a stock 2.5L.


Mac said:
also i've heard some positive and some negative info about Polishing the manifolds as well as the TB... some people say that the textured roughness on the UIM and TB shouldn't be smoothed out, something to do with the way the air passes by it? any insight on that?
Click to expand...
Porting is good when the engines abilities can be increased with the additional air needed. Leaving a huge conversation a side.

Polishing would only be recommended for heads. Not UIM OR LIM OR THROTTLE BODY. I myself create a lighter rough surface to help the entrance and exit lip to be removed creating Less turbulence on the throttle body.


Mac said:
ans lastly, if i were to enlarge the primary LIM ports only, and port match the UIM to it would that cause any problems? i'm thinking that since the 2.5L doesn't need the top end help, that doing this would help out a little bit on the lower end... any thoughts would be appreciated!
this might be a totally bad idea but i'm just curious...
Click to expand...

Bad idea when looking at the LIM. Your UIM/LIM work fine, enlarging them won't do much IMHO. I've had the big bore lim. A enlarged ported UIM (done myself). Leaving them stock is optimal for daily driving and a once and a while quick acceleration.
 
ok. :cool:

correct me if i'm wrong but have some people removed the butterfly plates for the secondaries on the LIM? i thought i've heard of somebody doing that...

also it seems like the LIM's butterfly plates can be optimized just like the TB as far as removing half the bar and then maybe even knife edging the plates... i could be wrong here but i'm just curious...

i guess i'm just trying to figure out what else i might be able to do to the intake manifolds or anything else since i have everything taken apart right now... bagged along with yourself, Harry, have given me some suggestions but i'm just curious to see if there might be anything else... probably not, but i feel it's worth my time to find out...

-Mac
 
Mac said:
correct me if i'm wrong but have some people removed the butterfly plates for the secondaries on the LIM? i thought i've heard of somebody doing that...
Click to expand...
Do not do this! Unless you have a 3L installed..and have a tuned designed to eliminate the secondaries from the pcm.

Mac said:
also it seems like the LIM's butterfly plates can be optimized just like the TB as far as removing half the bar and then maybe even knife edging the plates... i could be wrong here but i'm just curious...
Click to expand...
Yes they can. I have done 3 so far for 2 other people including myself. They are a pain in the arse. I am half way into another one. But just don't have time in finishing it.

Mac said:
i guess i'm just trying to figure out what else i might be able to do to the intake manifolds or anything else since i have everything taken apart right now... bagged along with yourself, Harry, have given me some suggestions but i'm just curious to see if there might be anything else... probably not, but i feel it's worth my time to find out...

-Mac
Click to expand...

I did every mod possible to a 2.5L except changing the heads and engine itself. Every bolt on was done...true duals, headers, pulleys, mass air meter, tb, big bore lim, acid ported uim....Ported the heads...the list goes on.

After all said and done...it was quick. i ran in the 14's with my 18's on. Before i did the lim and uim and head work. After all the work...i sold it unexpectedly to an old man who fell in love with it the first time he saw it. Gave me an offer i couldn't refuse and he took it home. Never knew what numbers it put down or how fast it really was in the end.

But i was running according to a tuner 11.0-11.2 afr. So it needed a tune bad! I always wanted to break the 200whp on a 2.5L. Oh well. :laugh: Maybe later i will.:shrug::cool:
 
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I feel like if you wanted to port something, port the secondaries. But like Harry said, you won't really get anything on a stock engine. To make decent low end power, you need smaller diameter runners and they need to be a little bit longer, and for top end power, you want shorter, bigger diamter runners. What the secondaries do is combine the two, giving you a much broader torque curve. But if you only port the primaries, then you lose a lot of low end torque and really wouldn't gain anything up top. On the flip side, if you port the secondaries, you might see an improvement in the top end and still have that low end power, but you really wouldn't see anything significant on a stock engine.

In all reality though, making a port bigger doesn't do that much for air flow anyway, mainly because the biggest restriction is at the valve throat. (Essentially it is the diameter of the valve seat). Yes, you can make a more drastic tunnel effect but that really wouldn't do much difference either, Ford has spent months optimizing the factory system. People would often port out heads in areas like tight bends and where the valve stems come into the cylinder, but I don't think they is much to the ports on these heads. They have a really nice shape to them as they are...
 
Coming from V8 land, I was all set to get a PP'd intake but after research. Nope, will not be touching the 2.5L anything. When I do eventually go to a 3L I'll go full 3L and then start hunting around ebay.uk for a ST200 intake to get extrude honed ala CSVT#49. Everything I've read says that messing with the CSVT LIM/UIM is negligible at best and the cost is horrific anyway. If you want to do something to your intake then pull the whole thing out and clean it with B12 solvent. The how-to is in the archives in the FTP link.
 
yah i just finished cleaning my UIM and LIM and TB, and i could deff tell a difference in everything from smoother idle to better throttle response..

-mac
 
Did you remove the UIM/LIM? I was shocked at how much of a difference it made the first time I did it. Now I try to do it at least once per year.
 
You don't port or polish anything unless you have the tools, knowledge, confidence and are ready to go out and immediately buy another intake if you bugger this one up. It really is a job better saved for a machine shop that specializes in porting/polishing.

As for cost... depends on who does it, type of intake and the vehicle it came off of. For instance, a Mustang lower intake is relatively cheap to get ported/polished, from what I've seen, the contour intake will be more expensive for a few reasons.

As I stated before, you are not going to see any real benefit from PP'ing an Contour intake. Huge waste of money IMO. The only thing I've seen on here that I agree with as far as Contour intake porting is CSVT#49s extrude hone of a ST200 upper intake. It really cleaned the intake up and it wound up being port matched exactly to his escape LIM.
 
To the person above ^^Any contour svt has the extrude honed process level 1. Which was an increase from the stock 2.5L uim. So the inside is smooth to a nice finish.Were talking a 168 cfm flow over the stock 155. Extrude honed (max) 3 pases puts cfm flow at around 190-192 cfms. I have a full write up on this on here. I just don't feel like searching for it. :crazy:

Asking your age was not because i thought less of you...but rather your recent abundant amount of questions to modding your car.

Scotty is right...if you have to ask about how to do this process...then please don't tackle this yourself.
 
Okay, but I asked because i was just curious.


Harrry said:
To the person above ^^Any contour svt has the extrude honed process level 1. Which was an increase from the stock 2.5L uim. So the inside is smooth to a nice finish.Were talking a 168 cfm flow over the stock 155. Extrude honed (max) 3 pases puts cfm flow at around 190-192 cfms. I have a full write up on this on here. I just don't feel like searching for it. :crazy:

Asking your age was not because i thought less of you...but rather your recent abundant amount of questions to modding your car.

Scotty is right...if you have to ask about how to do this process...then please don't tackle this yourself.
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I'd still have to see before/after dyno results on the whole intake port/polish for a 2.5L motor. Not saying it doesn't help though. What cfm do the CSVT heads max out at? SO many ppl in Mustang land will do all this work to intakes/get bigger throttle bodies etc... not realizing that there is only so much before the heads they have just can't use it anymore and actually start to lose power from a loss of velocity. I've learned to be very wary about opening up intakes, that's why I did a good deal of research before I bought my 65mm TB from you lol. This is also why my Cobra doesn't have all the omfgwtfbbq high flowing parts that so many guys out there slap on. I make more power with my Cobra using "inferior" Edelbrock heads, a ported OEM Cobra intake and a second hand off the shelf cam than many people with AFR heads, RPM II intake and custom cam and honestly it is quite amusing.

With that said there probably is some benefit to porting/polishing the CSVT intakes to max CFMs, my whole thing is that it really doesn't seem cost effective for what you get. You can get a low mileage 3L motor plus some other goodies for the money it'll take to get the LIM ported/polished/bigger secondaries and an extrude honed UIM.
 
ScottyDsntKnow said:
With that said there probably is some benefit to porting/polishing the CSVT intakes to max CFMs, my whole thing is that it really doesn't seem cost effective for what you get. You can get a low mileage 3L motor plus some other goodies for the money it'll take to get the LIM ported/polished/bigger secondaries and an extrude honed UIM.
Click to expand...


Yes max extrude honing has been shown to provide very little power..because the svt 2.5L has and is close to maximizing it's flow potential! Now having that item on a 3L is a different story!

Max extrude honed made 1.1 whp and 1.2wtq. Back to back run the same day! Which obviously has shown very little gain. But an se with an svt uim has shown a gain of 2.4whp and 3.2wtq.

Without knowing flow characteristics or geometry of the uim. The proof is in the numbers. Showing us the uim is not a restriction anymore on the svt engine.

The heads are fine...unlss you want to clean the dome. The inlets should not be touched.
 
Lol, I'd be mad as hell if I got those numbers back after spending $500+ on porting/gaskets/whatever.

I did see CSVT#49's pictures of his extrude honed ST200 and that looked delicious. IIRC it miraculously matched up to his Escape LIM dead on. Port matched runners ftmfw!
 
Harrry said:
The heads are fine...unlss you want to clean the dome. The inlets should not be touched.
Click to expand...

So Harry what do you think about the 3L heads? I've been debating about doing port and polish work on them. I've been reading up a lot about it on a few other forums. I know a few people got the Kinger P&P heads... but I don't think he is in the business of doing those anymore.
 
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