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Discussion Starter #1
In the ongoing quest to make more power with our duratec 3.0L, thoughts of a larger TB has always been on my mind. The mustang modular engines have showed promise thru the use of larger TB's. Which turns into easy bolt on power increases.

I was looking at trying the 4.0L mustang v6 TB. But why try that when our new 6 generation has a bigger TB than the stang.

Anyway, this is basically going to be a joint effort here between myself and Scott(twowheelin) to make it so our 3.0L can use our bigger brothers TB. For comparison the optimized 3.0L TB is only 60mm in diameter. The optimized 3.7L TB is a whopping 72mm in diameter. That is a huge increase over the stock 3.0L TB.

Simply put...more times then not more air means more power capability.

Scott was kind enough to let me use one of the 3.7L TB's from his stock to work on this. Thank you very much scott.

This thread will be a running log of the R&D I will be doing to get this mod a reality. From possibly making an adapter plate as well as seeing how far I can go (if need be) with porting the intake manifold entrance to better compliment the bigger TB.

All updates, testing, and any issues will be posted here as I work on this. So those who are interested in this mods outcome sub up and stay tuned.
 

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Discussion Starter #2 (Edited)
UPDATE: (11-19-2010)

received the 3.7L mazda 6 throttle body today. immediately took it out of the package and started measuring.

first things first....the 3.7L TB is huge compared to our regular 3.0L TB, i mean it literally swallows our lil 3.0L TB

first part of the good news is. after measuring and inspecting the bolt pattern. go figure, like Scott and myself suspected there are close. not only are they close, but they are identical

like i said it seems they just made the bore larger but didnt move the bolt holes. if you look at the 3.0L TB you can see how much material there is still between the bolt holes and the bore. they may have just changed the electronics around to facilitate a larger bore.

pins look the same, same exact plug. i'll big going thru the wiring to make sure its all pinned the same and at a quick glance prior to receiving the unit. the wiring looks the same.

here are the pics so you can see what im talking about.

left is 3.0L and right is 3.7L





Left is 3.7L and right is 3.0L





And Heres the 3.7L TB literally swallowing the 3.0L TB








UPDATE: (11-20-2010)






UPDATE: (11-21-2010)

Got to work today and starting fit testing the TB on the intake manifold. As I said the bolt pattern is indeed the same and bolts right up.

But as I suspected the extra bulge that I noted previously as possibly being a problem is indeed hindering bolting up the tb. By a 1/4" worth of issue at that. And more at about a 3/4" if clocked the other way




So this determines that a spacer will be needed for this mod. One more thing I noticed that I completely forgot about until I pulled off the stock TB is that the stocker has a block built into it to cover an auxillary air channel on the intake manifold. Shown below:




The 3.7L TB does not have this block for that air channel. No biggie. Ill explain why later.

Onto the intake manifold. Now remember me saying that porting the intake manifold a lil bit would be the path to go for acheiveing max potential of this mod. Or at a minimum the I'M neck entrance. Good news is there is plenty of material to take away to port match the I'M with the TB. Notice the portion of plastic I'M material on the inside of the oring gasket. There is approximately 3mm of material there inside the oring gasket. Look below:




Now..I went further in looking at the I'M and relized that you can indeed take all of that 3mm out of there. Because for one...with the 3.7L tb you will not be able to utilize the stock oring gasket. At least around the main bore. So converting to a paper gasket would be the route of choice. Why can't we use the stock gasket? Well the 3.7L TB sealing surface is to big of diameter to mate up to the stock gasket. Its bigger by about a CM. Look below:



You can see the gasket poking out decent on the right side. Paper gasket it is and get rid of all the material via porting. Which is better anyway.

Good news is...we already have a spacer made for our car. STeeda TB spacer anyone? I will have to get one and mount it up and see if that needs any porting as well. So it seems the used to be somewhat meaningless mod may actually have some use now, lol. I'm going to be sourcing a TB spacer since its already made why waste time making another one. So if anyone has one laying around. Please let me know.


So this mod is definitely doable. Seems to me like its only going to take some porting to the I'M neck and a spacer to bolt it up "properly". Not bad at all iMO

Now since I had the I'M in front of me. I went futher into looking at porting the runners. Since I already did my lower intake manifold porting a long time ago. May as well do the upper I'm as well to compliment this mod even more. This isn't something that is 100% required to make this work. But if the owner is looking at maximising gains with the larger TB its some to take into account. And go figure there is a whole lot of material on the runners that can safely be ported out. Between 3-4mm in some places. So u can safely leave about 1mm to house the oring seals like stock. Look below:




So I'm going to proceed with getting this to work. Good news is being as our manifold is plastic its a breeze to do the porting. So a simple dremel and a good eye for smoothness is all that's needed.

Again if anyone has a steeda TB spacer laying around. Please let me know. It will expedite the process..lol



UPDATE: (11-29-10)


BAD NEWS....

got an email from steeda saying that the spacer is back ordered till almost the end of the month...WTF!

GOOD NEWS......

this is why i love networking in the car game. go figure i know someone else with a machine shop. lol. canceled my order at steeda (saved $80+) my boy said he can do it at the end of this week. 1/2" spacer made to whatever center bore i need for $50 bucks. so im dropping my spare TB off to him tomorrow and giving him the diameter i want the center bore to be. the spacer is gonna have a 75mm main bore. no taper at all.


i also mentioned to him that i may need more of them made if this takes off as a mod. so $50 will wind up being cheaper than that at a couple units per run. so we have a lil delay, but this project is still moving.
 

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Discussion Starter #3 (Edited)
UPDATE: (12-3-10)

picked up the spacer today. looks great.





he made the spacer exactly as i needed and asked for. i will definite be bringing business back to that company. met the timeline and produced my item to the specs i gave them. AWESOME!!!

now there is a lil snafu. this snafu is 100% completely my fault. when i gave him the specs for the center bore, i told him i needed it to be 75mm which he made it precisely as i asked. but i screwed up and gave him the TB inlet size. the rear of the TB is actually about 70-71mm. so the center bore is too big. so i'll be asking him to make another one with a 70.5mm center bore. im still going to use this on in the mean time. it fits fine. only there is more of the intake manifold showing that i wanted. for when i bore out the IM. see below:




no biggie, i'll just get another one made next week. but use this one for the mock up and get it on the car and run the car with it. again this was my fault and the machine shop had nothing to do with the mishap. they made it exactly as i asked.


here is the 3.7L TB bolted up to our stock 3.0L manifold....SO PRETTY!!!









i'll be making the gaskets tonite when i get back home. i have some business to take care of so i have to run back out. stay tuned.


UPDATE: (12-5-10)

just came back from about an hour long ride with the 3.7L TB on my car. so far everything is copastetic. no CEL's have popped for the TB. no pending codes as well. this ride i actually didnt disconnect the battery as i wanted to see how it reacted to the change fuel trim wise by a quick swap.

went to check fuel trims and my logging software is being screwy and not reading the PIDs i want it to. for some reason only engine RPM is coming up. so i'll figure out whats up with that and log fuel trim differences if any. now i havent ported any of the intake manifold inlet thus far as i want to see what happens with just a direct swap and no added variables.

FIRST THOUGHTS:

well, i was pleased to see that the car started up immediately with the larger TB on it and held its regular 2000rpm (approx.) high idle for warm up and gradually settled into 750rpm +/- 10-15rpms (which is normal on my car)

no difference in idle until it was FULLY warmed up. once it was at full operating temp it seemed to smooth out the idle a bit. my wideband didnt seem to jump around past 14.7 as much. kinda hovered there quite a bit better. it also reacted to quick blips of the throttle a lil bit better as well.

So i took it out for a spin and told myself i would just cruise around regular without boosting. but yet that didnt last too long, lol. while cruising around i took note at giving the car various combinations of throttle input versus load. IE- at a given rpm in a respective gears and vehicle speed. i did this in order to see if any hesitation would be present and to also see if it made lower RPM acceleration any easier. coming to stop lights i noticed the car drop back to idle and level out without dipping. not sure if it was because it was a new TB or not, but for reference my other TB is sparkling clean due to the meth injection so i wanna say i dont think it was that.

also while cruising i noticed that during part throttle acceleration that my AFR would go leaner on the intial pedal press than before. i wanna say around .3-.4 more. this tell me or rather leads me to believe that the car is ingesting more air. i will verify via fuel trims when i get my logging equipment in order and reading correctly

i do notuce quite the bit more responsiveness from this larger TB. i noticed it the most while taking off from a light or stop sign. it was butter smooth or for better terms a lil more effortless or punchy.

it definately seems to have a lil easier time accelerating with less throttle. so im definately happy about that.

i wanna say that the biggest thing i noticed on my car specifically is that the boost hits faster and pulls harder once its there. so i think my powerband possibly may have shifted to a lil earlier onset of the rpm range. up top its just nutty, lol. i do 100% feel more juice up top. and i do think i feel the onset of boost come in slightly earlier for me. but i wasnt paying attention to my tach this time. i was going off of feel since i know my car.

overall im impressed with the mod. thus far no issues, and im glad i did it. just a lil hour ride in my car had me checking my mod fund account so i can buy the TB from Scott and just keep it. at the price of the TB and the spacer, its still less cost than the regular 3.0L TB, and to me thats big because we are all modders and this will leave room for more growth power wise for whoever buys it. i cant speak for gains on an NA 6, for obvious reasons, but i would assume an NA guy would see way better throttle response and easier higher load acceleration than with the 3.0L TB but until someone tries it, thats all moot and speculation.

im gonna get the new spacer made this week with the 70mm bore and scrap the one i have now. make some new gaskets for it as well. and rebolt it on.


thus far the only way to bolt it on is with the gear package facing the front of the car. if it was spun the other way, all those coolant and vaccum lines need to be messed with. facing it towards the front you only have to run the connector underneath the TB and unhook the Front bank upstream O2 sensor from its fastener.

heres some pics:







and here is what i was talking about with the O2 sensor plug hold down....



un-clipping this and moving it is a lot easier and cleaner than having the TB rubbing on coolant and vac lines or having to reroute them. just my opinion.

im gonna take another look thogh to see how much issue it would be to face the gear package towards the rear of the car



THE CONS:

i broke my fucking hood mirror when i closed the hood. it sits higher than the other TB due to the position of the gear package. so yea. closed the hood. heard a snap and opened the hood to see one of my mirrors cracked. FML!!!!

you guys wont have to wrry about that. if i didnt have mirrors under my hood there would still be about an inch and a half of space to play with.



UPDATE: (12-7-10)

got some solid info on whether or not this bigger TB did anything. got out there tonite with the 6 and hooked up my logging stuff. logged STFT's for both banks and yea, trims changed at idle a bit. and holding at 2000rpms....changed a bit more.

@ IDLE

before 3.7L TB - trims were tuned in at +/- 1% at idle. every so often it would hit 3 randomly.

after 3.7L TB - trims were now showing a higher value on the lean side. meaning the ecu was adding fuel to compensate. trims got up to about 3-4% steadily and only saw a 1 on the negative side twice


@ 2000rpms

before - trims were pretty much spot on

after - i saw between 5-7% while held at as close to 2000rpms steadily.



this may not sound like much, but also take into account that my injectors are double the size of whats in your car. so the change is not as apparent since it takes less adjustment to compensate on my car. stock injectors would probably show slightly more correction.

timing and such seem to be the same so thats another bit of info i figured i'd throw out.

now that i logged the trims. i went ahead and trimmed it out for the correction on my car and we are back to the original +/- 1% or so.

again, this is without the manifold ported yet. so it seems the TB is doing something. at least on my car.
 

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I'd wager the improvement would be solely from the improved interior shape and finish.

The stock TB flows CFM far beyond what a naturally aspirated, low-rpm V6 needs. If a 5.0L Mustang can roll out of the factory with 60mm, a 3.0L V6 doesn't need anywhere close to 72mm.
 

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well, we do have 24 valves, i guess as long as we can get more fuel(with help from tuner) to go with that extra air from that larger TB, it should make a diff.
 

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Discussion Starter #9
I'd wager the improvement would be solely from the improved interior shape and finish.

The stock TB flows CFM far beyond what a naturally aspirated, low-rpm V6 needs. If a 5.0L Mustang can roll out of the factory with 60mm, a 3.0L V6 doesn't need anywhere close to 72mm.

NA motors make power generally from how easy it becomes to do work. IE- opening flow from air ingestion to combustion expelling. intake, headers, porting and etc. just because something comes from the factory with one thing does not mean its the end all MAX performance promoter for that particular application. you've been around long enough to know (whether you want to believe it or not) that the duratec family has been known to take very well to flow increasing mods. ours in general being as it has VVT would benefit and probably show more gains than the earlier duratecs that are found in the taurus, contours and etc. as for the 5.0L im not sure if your talking about the new 5.0L or the old foxbody, but on the old FI foxbody, iirc increasing the TB size was common and they only came with 225bhp.

obviously a NA build with raised compression or a boosted application would benefit more from a larger TB than a stock 3.0L would. that is known fact. but in return, both applications will see gains, one just more than the other. the gains worth is owner dependant on price per HP generally and drivability concerns if any. none of which has been accounted for just yet.

gains will not only be from the smoother transition of an "optimized" tb (not stock 3.7L tb, but because of the increased airflowand the ease of getting the needed CFM's into the motor will also make power. because on NA motors the easier it is to do work the more power can be made. and tuning is just another way to maximize the gains


So do you think the intake is still going to fit the same?
...will need a new accordion or adapter. Should be a simple fix.

the intake will fit exactly the same outside the elbow needed to mate to the TB. it will definately need to be addressed. but like sandman said, "simple fix"





i will be mounting the 3.7L TB on my spare intake manifold today after work. this will allow me to start taking visuals and actual measurements of the intake manifold neck to see how the transition is from the larger bore to the stock manifold and get an idea of how much material would need to be ported away (if any) to have the manifold compliment the larger bore TB.

i will also look at the gasket and see if that will need any attention.

stay tuned.
 

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You missed my point.

Using any of the various calculators available online, a naturally aspirated 183c.i. V6, with a single plane intake, 87% volumetric efficiency, and 7000 RPM redline, needs approx 325 to 430 CFM of airflow.

Things like multi-valve do not require more airflow; they help the engine use the airflow to improve volumetric efficiency. It's ultimately the displacement, RPM and N/A vs. non-N/A that determine how much airflow an engine needs.

Thanks to people who spend hours combing the Internet gathering articles, test results and manufacturers data, you don't have to search too far to find common flow numbers.

Starting with Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software I found one person who gathered a pretty good collection of TB flow numbers for (their) conversation on TBs. The point is to show a rough average of CFM across the various sizes. There is nothing about the Duratec V6 that makes it require anything near a 72mm TB. Cleaned-up and improved? Sure. 72mm? No.

Throttle Body CFM Flow Ratings:

Stock 5.0L 60 MM - 526 CFM
SVO 65 MM - 540 CFM

Accufab:

65 MM - 664 CFM
70 MM - 787 CFM
70 MM - 896 CFM (Race version)
75 MM - 924 CFM
75 MM - 1045 CFM (Race version)
80 MM - 1142 CFM
85 MM - 1322 CFM
90 MM - 1369 CFM
105 MM - 1550 CFM

Holley:

65 MM - 750 CFM*
70 MM - 790 CFM*
75 MM - 840 CFM*
80 MM - 892 CFM*

*Information given by Tech Rep.

BBK:

70 MM - 726 CFM

Edelbrock, Ford Racing and Proffessional Products have no cfm information after calls/emails.

I'm not saying people shouldn't look to make improvements, but I'd not spend money first on a new TB when simply cleaning-up the stock one would likely provide the exact same results. Get rids of the poor casting quality, the huge ledge inside, and the throttle shaft as thick as a baseball bat and I'd wager you'd see the same results as-if you then opened it up. Only the dyno is going to show that.

I'm not at all surprised the mounting is the same; TBs are a part that are really starting to be used generically across engine lines and displacements within manufacturers.
 

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Discussion Starter #11
you're missing my point

so in essence the 3.7L V6 comes with a TB thats too big for it? thats basically what that post is saying.

they put it on there for a reason IMO. i understand what needs what and etc. but the fact is those numbers are only a representative of what the minimum diameter is before the TB chokes off the engines ability to make power. that is all those numbers mean. period. that has nothing to do with running bigger diameter TB's to allow more power to be created easier in terms of how many CFM's can be passed through the TB in a given time
 

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you're missing my point

so in essence the 3.7L V6 comes with a TB thats too big for it? thats basically what that post is saying.

they put it on there for a reason IMO. i understand what needs what and etc. but the fact is those numbers are only a representative of what the minimum diameter is before the TB chokes off the engines ability to make power. that is all those numbers mean. period. that has nothing to do with running bigger diameter TB's to allow more power to be created easier in terms of how many CFM's can be passed through the TB in a given time
It's a very common practice. As long as the bore of the TB is not larger than that of the inlet, a larger TB will not act as a restriction. If you are a manufacturer and have engines ranging from 2.5 to 5.0 liters, you could easily get away with the same TB on all of them provided all intakes are sized accordingly (and electronics are compatible) A larger TB doesn't mean by default more air is going into a naturally aspirated engine.

Using a larger TB only provides a naturally aspirated engine with the opportunity for more air; it doesn't mean utilization of more air. A naturally aspirated engine will only take in as much air as the mechanical parts will draw. If you place a CFM meter on the inlet of a naturally aspirated engine at idle, it will only draw in XX cfm of air; doesn't matter if it's a 50mm or 70mm TB, as long as it meets the mininum need of the engine and assuming same design/quality. And the CFM would progress exactly the same up the RPM range, again assuming the smallest one at least fits the need.

You can have a 65mm TB with poor quality, an interior ledge, and over-sized shaft that flows less CFM than a 55mm of good quality. BBK proved that years ago with their line for Mustangs and continued to do so as they moved into imports and other domestic engines.

A manufacturer like Ford can spec a TB of any size they want; it's not the mm that jacks up the price. If XXmm didn't flow enough air, why wouldn't they simply use a larger unit to begin with?
 

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A manufacturer like Ford can spec a TB of any size they want; it's not the mm that jacks up the price. If XXmm didn't flow enough air, why wouldn't they simply use a larger unit to begin with?
Karlt10 your point is well taken, but it also points out the obvious; Why did Mazda engineers "spec" incredibly restrictive headers with precats? Why not a light weight flywheel from the factory? Why not a cold air intake? All of these are proven performance improvements???? For a company that screams "ZOOM ZOOM" you think they would have spent a little more time tweeking. Engineers don't always get to "spec" the best combination of parts for a miriad of reasons, cost, time, product differentiation, who knows. Will a larger TB make more total horse power? Probably not, but it may improve throttle response and low end torque and be a simple swap/mod for somebody who doesn't have the tools to start grinding on the stock parts. Either way, I bet in about two weeks GreatNY will have test data to look at and make a decision.
 

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Should be interesting to find the results. Doesn't hurt unless someone is willing to take the time, effort and a throttle body.
 

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Discussion Starter #15
Should be interesting to find the results. Doesn't hurt unless someone is willing to take the time, effort and a throttle body.
Haha..I'm always trying different stuff. I'm gonna do some more testing tonite after work
 

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Karlt10 your point is well taken, but it also points out the obvious; Why did Mazda engineers "spec" incredibly restrictive headers with precats? Why not a light weight flywheel from the factory? Why not a cold air intake? All of these are proven performance improvements???? For a company that screams "ZOOM ZOOM" you think they would have spent a little more time tweeking. Engineers don't always get to "spec" the best combination of parts for a miriad of reasons, cost, time, product differentiation, who knows. Will a larger TB make more total horse power? Probably not, but it may improve throttle response and low end torque and be a simple swap/mod for somebody who doesn't have the tools to start grinding on the stock parts. Either way, I bet in about two weeks GreatNY will have test data to look at and make a decision.
My points on spec'ing what TB they wanted were made in reference to Ford and the Mustangs, especially the SVT version. I have no doubt they'd call for -and get- a larger TB if that is what the car needed to gain needed HP.

I wouldn't expect Mazda to be going for all-out HP in any way; they don't have a history of it. They go for decent power with an emphasis on better handling. And I wouldn't expect them to when relying on Ford's bread & butter V6. If Ford has shown anything in the last 15 years, it's that outside of the Mustang and F-series, they're not concerned with being on top on the HP wars in the US. Look at what they did and could have done with the SHO and Contour SVT. We get one decent version of the Focus, and it's below half the trim levels available in Europe. US gets a 200hp 'Five Hundred' - Australia has a 350hp RWD mid-size sedan. They're not trying to be the performance US brand.

Spec'ing a 60mm TB vs. a 50mm is one thing. Spec'ing mass produced headers vs. manifolds is another. True, Acura has used what are essentially cast-iron headers for more than 15 years, but that's Honda/Acura. Cold air intake? Not only would the water intake risk be a huge risk, but large manufacturers are not going to put a car on the showroom floor making the noises/hissing that come from having a CAI. They even put baffles on regular air box intakes just to cut noise.

Cordoba has a before & after dyno chart on their site. Yes, it shows a couple of HP, but there are so many variables that a couple HP may mean nothing:
Was the existing TB in perfect, clean, working order?
Was the optimized TB tested BEFORE being optimized? If not, testing it as optimized-only is mute as you don't know if simply installing a clean, new TB added HP.
Was the battery disconnected during the TB swap? That right there is another variable.

I have no doubts the throttle response might improve, but I still doubt the increased bore is adding any HP (or torque). Dyno existing TB in clean condition - dyno a new, stock, unmodified TB - dyno a new stock 'cleaned-up' TB - dyno a new, 'optimized' TB. Compare all the numbers.
 

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Discussion Starter #19
anyway, i kinda eyeballed the way the connector is. the housing for the actual gears of the TB is slightly different than our stock one. it has one buldge on it that ours does not.

but looking at it. i do believe if i face the gear toward the front of the car it will fit right in without the bulge hitting anything on the manifold. if i put the gears toward the firewall like our stock TB it will hit something on the intake manifold. on the neck of our intake manifold right behind where the TB meets the manifold on the fiirewall side there is a protrusion that sticks out off the manifold pretty good and it will definately interfere with mounting it. so im gonna face it towards the front.

what im trying to do is make this as bolt on as possible with the least amount of modifications.


tomorrow im taking the 3.7L TB and my spare manifold to my job (i should have some free time a bit tomorrow) to see about any needed porting on the neck and if its needed or not. and to also check out the gasket to see if that will be an issue as far as placement to mate up to the larger TB
 

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Discussion Starter #20
UPDATE: (11-21-2010)

Got to work today and starting fit testing the TB on the intake manifold. As I said the bolt pattern is indeed the same and bolts right up.

But as I suspected the extra bulge that I noted previously as possibly being a problem is indeed hindering bolting up the tb. By a 1/4" worth of issue at that. And more at about a 3/4" if clocked the other way




So this determines that a spacer will be needed for this mod. One more thing I noticed that I completely forgot about until I pulled off the stock TB is that the stocker has a block built into it to cover an auxillary air channel on the intake manifold. Shown below:




The 3.7L TB does not have this block for that air channel. No biggie. Ill explain why later.

Onto the intake manifold. Now remember me saying that porting the intake manifold a lil bit would be the path to go for acheiveing max potential of this mod. Or at a minimum the I'M neck entrance. Good news is there is plenty of material to take away to port match the I'M with the TB. Notice the portion of plastic I'M material on the inside of the oring gasket. There is approximately 3mm of material there inside the oring gasket. Look below:




Now..I went further in looking at the I'M and relized that you can indeed take all of that 3mm out of there. Because for one...with the 3.7L tb you will not be able to utilize the stock oring gasket. At least around the main bore. So converting to a paper gasket would be the route of choice. Why can't we use the stock gasket? Well the 3.7L TB sealing surface is to big of diameter to mate up to the stock gasket. Its bigger by about a CM. Look below:



You can see the gasket poking out decent on the right side. Paper gasket it is and get rid of all the material via porting. Which is better anyway.

Good news is...we already have a spacer made for our car. STeeda TB spacer anyone? I will have to get one and mount it up and see if that needs any porting as well. So it seems the used to be somewhat meaningless mod may actually have some use now, lol. I'm going to be sourcing a TB spacer since its already made why waste time making another one. So if anyone has one laying around. Please let me know.


So this mod is definitely doable. Seems to me like its only going to take some porting to the I'M neck and a spacer to bolt it up "properly". Not bad at all iMO

Now since I had the I'M in front of me. I went futher into looking at porting the runners. Since I already did my lower intake manifold porting a long time ago. May as well do the upper I'm as well to compliment this mod even more. This isn't something that is 100% required to make this work. But if the owner is looking at maximising gains with the larger TB its some to take into account. And go figure there is a whole lot of material on the runners that can safely be ported out. Between 3-4mm in some places. So u can safely leave about 1mm to house the oring seals like stock. Look below:




So I'm going to proceed with getting this to work. Good news is being as our manifold is plastic its a breeze to do the porting. So a simple dremel and a good eye for smoothness is all that's needed.

Again if anyone has a steeda TB spacer laying around. Please let me know. It will expedite the process..lol
 
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