This is the port shape of this FP 62mm TB in comparison to the OEM 55mm TB (the BBK #1763 62mm TB port shape is very similar to the OEM 55mm TB-just larger butterflys...I'll take a picture of it & post it later), there is definitely an airflow improvement between the 2 as proven by the PCM readjustment numbers for fueling\TPS angle% at same idle speed on same tune operating under similar conditions & I don't think it's all due to just the larger TB butterfly blades as I had the BBK 62mm TB installed & when I pulled it & installed the OEM 55mm TB that came w\ the car I also noted that the TPS angle % didn't change w\ the 55mm OEM TB vs the 62mm TB at same engine idle speed (read in post #85) as it should've increased w\ the 55mm TB. So IMHO this porting design work on the FP 62mm TB has to be a contributor as well....from my understanding of airflow dynamics any porting that provides a more linear\laminar airflow path will incur less deltaP due to the absence of vortexing created from excessive port angles\shapes that cause airflow to oscillate (roll) thus will allow more air volume flow, especially just before coming into contact w\ the butterfly plates which would aggravate airflow passage thru them further due to the vortexing in the air stream than it would otherwise.
There is a substantiated, scientific & provable reason why Ford engineers designed this 62mm TB's porting in this manner as opposed to the production OEM 55mm TB design & I'm sure that they have all the wind tunnel & performance testing data to confirm this TB's port design efficiency improvements as well as the materials used in construction thus why they designed & marketed it for sale.
Now whether it's worth the $600.00+ price tag or not is up to the individual to decide.....not trying to sell it or provide rationale for it for anyone else, I just posted the info I witnessed from the install\operation of this part. I do know this though.....the 2 main areas where a larger TB design in general does make sense is 1.) improved throttle tip-in response off idle & 2.) max WOT airflow but there is a size limit that can be used w\o creating drivability issues at the low end. But you will need to upgrade the entire airflow tract thru the engine over OEM (minimum of CAI, intake manifold, cams, headers & FF exhaust) & retune the PCM to begin to take full advantage of it at a minimum as it is indeed a wasted design investment otherwise....unless the pure asthestics of it are what you desire as it is a good looking, very robust piece (machined out of billet aluminum so is not a casting which is reflected in it's price) which I do place some weight on (1 reason why I went w\ the BBK unit as it looks better than all the rest except the FP unit as there are 62mm TB's out there that are cheaper than either of these 2....1 in particular I know of costs about the same as an OEM 55mm TB does that also comes fully complete w\ TPS & actuator).
The only thing I can say I regret is not knowing of those 2 vent holes drilled in the BBK unit & the issue they can cause so I ended up wasting the $349.95 I spent on it that could've been put to the FP 62mm TB from the jump & not had to worry bout any leakage so the old adage still applies, "You get what you pay for....sometimes more up front is actually better\cheaper in the long run than less". But if you're a true car guy some of this is gonna be part of the total cost of ownership of these types of vehicles....so for me this is really small potatoes in the grand scheme of it all especially if you have\own a car that you like\want & intend to keep\not sell.
So in short it was worth it to me.
Actually, any bypass passage IS medtered air as it is after the maf sensor. There is actually a setting in the tune for minimum throttle angle at idle. It is normally set to 0, completly closed. Setting this to just under what you see at idle can reduce idle surge. This setting does the same thing essentially as the bypass passage.
Other differences noted make perfect sense, like less throttle opening for same idle speed. Nice work!
Hhmm…..that's good to know as I hadn't paid close enough attention to the sample tune files I looked at thru HPTuners Editor software to make note of that....gonna revisit to see if I can find that setting. I had read that you had to be careful when using the TPS stop to set the TPS angle due to the spring loaded tip (which is there for the PCM to use when it calls for the throttle to be set in limp mode) so as not to allow the throttle to go to 0% angle & maintain the max limp mode 1,000 RPM limit, thus why any Ford TB's have this stop set using a sealer to not allow it to be moved once it is calibrated. When I got this new unit it came w\ a warning to not try to readjust the TPS stop as it was sealed & you would only break it (which would also void the warranty as these TB's are warrantied by FP for proper operation\workmanship).
Yeah I do look at the PCM operational live data before\after whenever I do install\change a part to see if the part's design in question does cause a change in the data....another way to determine if the part may\will have an effect on the engine's operation to either improve or retard engine performance outside of a dyno as anything that causes\creates improved airflow thruput will cause\create improved HP\TQ once the fueling is matched to it & vice\versa if it retards airflow thruput. So far I have seen the before\after number changes thru the PCM operational live data that verified the FP Bullitt 85mm CAI, FP Intake Manifold, Lunati VooDoo #21270700 cams & FP 62mm TB all showing to move more airflow at idle when I installed them separately on my car vs the OEM part they replaced (already had the Kooks headers\catted mid pipe & Pypes Super Bomb FF exhaust installed but didn't have a scan tool at that time to check for any airflow changes, just assumed they were there) prior tuning so once tuned I figured I should get the most from them. It was very interesting to me that when I pulled the BBK 62mm TB & reinstalled the OEM 55mm TB (which both emitted the same TPS KOEO output voltage as I initially set the BBK 62mm TB's TPS stop to the OEM tune calibrated KOEO signal of 1.16v as output from the OEM 55mm TB's TPS stop setting before any PCM tuning was done) that the idle TPS angle% was exactly the same at the same set idle RPM's using the same tune file even though the actual TB butterfly blades were different sizes so from this data in comparison to the data I got from the new FP 62mm TB install that something else had to be in play to explain the increase in airflow thruput thru the FP unit at idle besides the TB butterflies & the obvious design difference is the FP's TB port design layout vs the OEM & the BBK units which share a similar port design layout that is easily seen to be a much better, less restrictive flowing design from a visual comparison standpoint...…….
PS--Just now caught my typo in earlier posting where I typed the KOEO TPS voltage difference @ .3v...…..should have typed .03v as if the difference was actually .3v the PCM would've probably had issues w\ that large of a TPS voltage difference w\o a tune adjustment to recalibrate...…
My bad....