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Whistles go Whoooooooooo
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Discussion Starter · #3 ·
right now just lt's and cai but whole motor will be gone through this spring looking at going 383 forged, heads and ported intake and cam so it will be built just wanna know what throttle body people recommend
 

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Whistles go Whoooooooooo
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That's the one I was gonna say to go with. Why not right. They're made just as well as the other brands. I am having mind installed by the engine builder. I would purchase it at build time tho
 

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All depends on the amount of coin u wanna spend. I have th edelbrock one. Came woth tps sensor also. For me im the type of guy where i like matching parts manufactures, example lunati rockers, timing chain etc. wish i had the trickflow tb.
 

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the 58mm is made for foced induction, turbo/supercharger/procharger.. the 52mm will be perfect for your setup my friend picked up a brand new 52mm on craigslist for $150 but they run about 3-400

 

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Cody...

Unless you have scan software and can do the "mod" to a 58 TB (typically drill the hole where it is on stock for IAC) don't get one. DON NOT BLINDLY DRILL THE HOLE WITHOUT FIRST SCANNING THE CAR TO SEE WTF YOUR IAC COUNTS ARE FIRST

If anythng have a stock 48 bored to 52, it will be more plug & play BUT may also require the hole be drilled out 1/64" more (mine did) when I went from 350 H/C motor to a 383

also on a 58 you will need to get the intake manifold machined out. Not necessary for a 52. So if you are hell bent on getting a 58 wait until you have the 383 built or you will need to pull your intake for it now.

Also any larger TB WILL require PCM tuning so again wait until you build the 383 and do everything at once
 

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U dont need to tune for the 58mm tb. Ran it on my car when it was basic bolt on car. If ur gonna buy a tb just get the 58mm and wait. Why spend money twice it be like getting stamped roller rocker arms then buying full roller rocker arms.
 

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I'd say stick with stock until you rebuild too. 52 or 58mm, the Professional Products TB seems to be a nice product based on all the positive reviews I see for it. Can't remember any complaints that's for sure.
 

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Bigger TB should be low on the list of mods. The stock one will support about 450 HP. I ran high 11's in the 1/4 with the stocker. Most people claim they get more HP from going to a larger TB when in fact it's feeling like that because you have to give it less throttle to achieve the same HP with the larger bores. With a NA engine it can only suck in so much air.
 

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U dont need to tune for the 58mm tb. Ran it on my car when it was basic bolt on car. .
well it is your car so do what you want...

But it is a known fact "tuning" of the PCM is required with a larger TB. More so to prevent transmission damage as line pressure needs to be increased for the transmission...at a minimum. "If" your tranny has had a shift kit put in the PCM line pressure increase need is less because the shift kit increased pressure. Shift points are affected with larger TB and those need to be adjusted in PCM though

your car will run and drive with just bolting it on...does not mean it is right.
 

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Yes, BALLSS is correct about tuning and line pressure. The low TPS voltage line pressure maps need to be increased significantly when going to a 58mm TB. With a bigger TB, the engine gets a much larger gulp of air with much less throttle shaft movement than a stock TB. Since the TPS voltage responds strictly to throttle shaft movement, the PCM only sees a small increase in TPS voltage when there is significantly more power being generated by the engine at a given TPS voltage than there was stock. This needs to be addressed in any A4 car...
 

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All I'm stating is that my 58mm tb full exhaust, 1.6 rr, 32 lb injectors went 13.2 untuned on beat street tires. So tell me how it needed to be tuned or anything adjusted? And I drove it like that for a year. It's the mafs job to know how much air is gonna go in.
 

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man oh man

thinking the maf can compensate for any modification because "it knows how much air is gonna go in" is a gross oversimplification of how maf based fuel injection metering works.

and i suppose going from 24lb to 32lb injectors is a small enough difference just to trim out? i guess the extra fuel might have put you in a better ballpark for AFR with those mods, but damn. fuel injectors aren't carb jets. that's the wrong way to do it.

why do cars have oxygen sensors and manifold pressure sensors and temperature sensors? i mean.. if the maf knows how much airflow there is, it can just dump the appropriate amount of fuel, and your AFR will always be correct, right?

just because it worked for you once doesn't mean it's good advice, and track times (which happens almost entirely in PE mode) are a HORRIBLE metric of how well a car runs under various conditions :craz28:
 

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Car also got 18 mpg on that setup. And i drove part city and highway to work. I mean it only lasted a year till i tore it all down to do my current setup which is going uder the knife again
 

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Nobody ever said that the PCM doesn't know how much air is entering the engine. Yes, the MAF will monitor that. The problem is that the transmission pressure maps are not tied to the MAF readings. They are based off of TPS voltage.

But, hey, if it worked for you... I guess I've been wrong all these years!
 
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