All of this throttle body shaft grind talk is .............
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MBWorld Fanatic!
Joined: Oct 2009
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From: Southern California
E55 w/ goods, Z32 Project underway
All of this throttle body shaft grind talk is .............
Dead on accurate. 
Figure I would finally get around to posting up some clear pics. Used a Dremel with an extension (flex shaft) which makes things easier, similar to using a heavy pencil. Started out with 60 grit, used a flat file to keep it straight, then 120, 500, 800, then polished up both sides. Duct tape on the bore in case of an accidental bump. Loctite on the screws. This is actually my second TB grind.
For anyone contemplating this mod, do it! It really does open up the breathing on the car from off the line to up top. For those claiming 20+hp. I would certainly agree.The power is not placebo, it is there, and everywhere.
I did not grind it down as aggressively as I could have as I enjoy a margin of safety. I purchased this unit off Ebay for $120. Would rather not use the TB off the car just in case......
With careful grinding/polishing-2 hours taking your time.
R&R with old unit-30 minutes including cleaning the inside of airbox, KK filters,etc. No error codes on either car. If you have other mods, IMO this is a must.
The OEM screws are 'pillars of restriction', I'm trying to source some nice counter sink versions.
Figure I would finally get around to posting up some clear pics. Used a Dremel with an extension (flex shaft) which makes things easier, similar to using a heavy pencil. Started out with 60 grit, used a flat file to keep it straight, then 120, 500, 800, then polished up both sides. Duct tape on the bore in case of an accidental bump. Loctite on the screws. This is actually my second TB grind.
For anyone contemplating this mod, do it! It really does open up the breathing on the car from off the line to up top. For those claiming 20+hp. I would certainly agree.The power is not placebo, it is there, and everywhere.
I did not grind it down as aggressively as I could have as I enjoy a margin of safety. I purchased this unit off Ebay for $120. Would rather not use the TB off the car just in case......
With careful grinding/polishing-2 hours taking your time.
R&R with old unit-30 minutes including cleaning the inside of airbox, KK filters,etc. No error codes on either car. If you have other mods, IMO this is a must.
The OEM screws are 'pillars of restriction', I'm trying to source some nice counter sink versions.
Last edited by pearlpower; Sep 6, 2010 at 04:08 AM.
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From: Jacksonville, Florida
2006 E55 AMG --old cars -- E39 M5, 2.7tt Audi S4, E36 M3 **Ducati 996, 748
yup, its free HP -- I love the free gains it gave me -- I have 2 TBs also -- and when I put the umodded TB on the car -- it is very noticable -- even my gf can tell the car is very different. I wonder what the dyno gains are but they are noticable -- must be 20whp if you can feel it when you have ~600crank hp... car is much more sensitive and responsive -
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Thread Starter
MBWorld Fanatic!
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From: Southern California
E55 w/ goods, Z32 Project underway
MBWorld Fanatic!
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From: Bay Area
2015 E63S, 2018 E63S
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V12TT
Beautiful. I'm interested to see a dyno stock vs grinded or some kind of proof. Just the "feel" of more power is still weird. I did this before, I have to grind my new TB soon.. maybe tomorrow
MBWorld Fanatic!
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From: Bay Area
2015 E63S, 2018 E63S
Super Member
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From: Jacksonville, Florida
2006 E55 AMG --old cars -- E39 M5, 2.7tt Audi S4, E36 M3 **Ducati 996, 748
I know one of the members knows a formula for this --
Super Member
Joined: Oct 2009
Posts: 923
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From: Jacksonville, Florida
2006 E55 AMG --old cars -- E39 M5, 2.7tt Audi S4, E36 M3 **Ducati 996, 748
a tune will always maximize gains, safety and driveability. if you are going stock to 82mm you will need a retune -- that is a huge jump and the computer will not be able to compensate adequately.
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E55 AMG, 72' Toyota Carina, 63' Ford F100, 72' Mercedes 250c, 15' Harley Davidson Softail
lol pretty much tbal. take your time, make sure you do it right and I would recommend polishing after you grind down. hit me up if you need any help Ive done a couple for some friends. I'll be tackling this once I get a baseline run since my EC long tubes are on order 
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From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
Nice job pearlpower....
Ok I get the fact that the cross sectional TB area is larger now allowing more flow but I dont see how it can bring about anything close to 20hp gains....esp when applied to the larger TB's....
Ok I get the fact that the cross sectional TB area is larger now allowing more flow but I dont see how it can bring about anything close to 20hp gains....esp when applied to the larger TB's....
