Ford Focus Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
102 Posts
Discussion Starter #1
Hey I was looking on marcymotorsport and seen that the throttle bodies are only a 2mm difference and was wondering if that was enough to effect my cars performance for over an additional $100. As the Cosworth is 67mm and the Fc is 65mm. My car is not heavily modded so I was thinking the 65mm but it says greater performance for the 67mm....so how much can 2mm add?
Thanks in advance. BTW 05 zx3 non pzev...
 

·
Registered
Joined
·
422 Posts
well, i know that when using the Cosworth TB, the stock intake manifold has to be modified to fit.
 

·
Registered
Joined
·
419 Posts
The Cosworth TB was designed for use with the Cossie intake manifold. The FC TB was designed as a bolt on for stock manifolds.
 

·
Registered
Joined
·
296 Posts
A TB will not make much difference regardless of size on a stock, or even lightly modded car.. It is simply for throttle response, it will not get you any serious HP or TQ gains.. Save your cash and get something else.
 

·
Registered
Joined
·
507 Posts
get the fc. I have it and like it
 

·
Registered
Joined
·
2,945 Posts
The st has a 65 mm throttle body from the factory.

Why not just get an st throttle body. Throttle bodies are going to be a waste unless you have a lot of serious mods. Why not get a bigger mass air flow sensor first. No point in a bigger throttle body, when your mass air flow sensor is still a restriction.
 

·
Official [FJ] Distinguished Advisor
Joined
·
19,806 Posts
Most of what people (who've installed aftermarket TB's on their otherwise stock engines) perceive as increased throttle response is merely a slight variation in the throttle pedal/throttle butterfly pivot ratio...

Not to put too fine a point on the subject, but a larger throttle body is, in my opinion, almost entirely unnecessary intil something like Cosworth's Level 2 has been installed.


I do, however, like pzev04boy's suggestion of using the slightly larger ST TB; it's just so factory...


And, in the light of Cali's NEW illegally-modified-emissions-equipment crackdown, this is a great stealth mod.
 

·
Registered
Joined
·
3,589 Posts
mmm, I love my ST
 

·
Registered
Joined
·
545 Posts
the throttle response comes at the principle that you have a bigger plate that is going to allow more air in if you rotate it the same number of degrees. other than that...i'm sure it's come up a hundred times that the MAF is more of an air restriction.
 

·
Registered
Joined
·
1,133 Posts
The st has a 65 mm throttle body from the factory.
So only in '05 did the 2.3 get a bigger TB????

What size TB did earlier 2.3's have??

And what size does the 2.0 Duratec have??
 

·
Registered
Joined
·
803 Posts
What size TB did earlier 2.3's have??
I was just wondering that...
 

·
Banned
Joined
·
1,327 Posts
Has anyone actually verified this by measuring them side by side? The 2003-2004 2.3 is 63.5mm and 1.5mm is an easy mark to miss with all the tapers in the TB.

The Cosworth TB has some nice detail improvements vs. the FC unit. Better throttle blade, larger, etc. The stock throttle body is pretty good in it's own right though, capable of supporting 180whp.

Under the 180whp mark, it's more about the bling than the bang for the buck. I'm not saying don't buy a throttle body, but maybe choose wisely for performance or just buy for style/name.
 

·
Registered
Joined
·
323 Posts
My '05 2.0 measured 65mm on the outside. I wonder if they are the same part #. Wait, does the ST TB whistle with a CAI? If not then I'm in for one.
 

·
Registered
Joined
·
507 Posts
I have an st and installed a fc throttlebody.
and no I wasn't hopeing for some big hp gain. but it did change the throttle response. and I like it.
 
1 - 15 of 15 Posts
Top