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[89Speedy]

Can anyone confirm our air intake system includes the Screamin Eagle 50 mm high-flow throttle body?  I understand Harley also makes a 58 mm throttle body.  I wonder how much of a difference 8 mm would be....

[Breakout]

The original throttle body installed on the CVO breakout is 50 mm.
The increase of the 8 mm is significant while it will increase the surface of the inlet by around 35%.
This will lower the velocity in the throttle body and so the resistance of the throttle body.
For example at 4000 rpm the air velocity in the throttle body will go down from 30.56 Mtr/second
to 21.71 Mtr/second so the differential pressure over the throttle body will more or less halve.
So your engine will breath more easely  , but more air means also more fuel  ,
so when installing the
58 mm throttle body you also have to install bigger injectors  !

[89Speedy]

The original throttle body installed on the CVO breakout is 50 mm.
The increase of the 8 mm is significant while it will increase the surface of the inlet by around 35%.
This will lower the velocity in the throttle body and so the resistance of the throttle body.
For example at 4000 rpm the air velocity in the throttle body will go down from 30.56 Mtr/second
to 21.71 Mtr/second so the differential pressure over the throttle body will more or less halve.
So your engine will breath more easely  , but more air means also more fuel  ,
so when installing the
58 mm throttle body you also have to install bigger injectors  !

Thanks for the info Breakout! I take it Harley makes larger injectors to go with their 58mm TB?  This sounds like a worthwhile mod, any idea as to the time/$ it would involve?  When you do something like this, does it impact or create another issue with the motor?

[Breakout]

See below the stuff from the screamin eagle catalog ,
The replacement of the throttle body and injectors is straight forward and can be done in a few hours , but afterwards you have to tune the bike and do that prefferrably on a dyno while otherwise you are investing a amount of money only to be left with a crappy running bike.
Also be aware of the fact that what comes in must go out so when installing the bigger throttle body the next restriction are the valves so to unleash the whole potential of the bigger throttle body an other camshaft is needed to increase the valve lift and timing , and so you are going from one mod to the next mod and keep on spending money.
By the way ,    There is also a 62 mm Throttle body

A.   SCREAMIN’ EAGLE® PRO HIGH-FLOW 58MM EFI THROTTLE BODY – Electronic Throttle*3
The biggest engines deserve the most fuel. This huge 58mm Throttle Body
won’t leave your engine starving for more air. The one-piece throttle body features Electronic Throttle
Control technology. Just add your stock injectors or the Screamin’ Eagle® Pro High-Flow Injector Kit P/N 27796-08
(sold separately). Stock injectors are recommended for engines making up to 100 rear wheel horsepower, Screamin’
Eagle High-Flow injectors are recommended for engines creating greater than 100 rear wheel horsepower. All
EFI-equipped models require ECM calibration (sold separately). For race application only.

27713-08    $399.95

Screamin’ Eagle® Pro High-Flow Injector Kit - 27797-08 Genuine Harley-Davidson® Product

Injectors provide fuel delivery at the rate of 4.9 grams/second, 25% more than Original equipment injectors. Recommended for use with engine configurations making more than 100 rear wheel horsepower. All EFI-equipped models require ECM calibration (sold separately). For race application only.
Fits Twin Cam models equipped with Screamin’ Eagle 58mm EFI Throttle Body P/N 27713-08

27797-08   $141.00

[89Speedy]

See below the stuff from the screamin eagle catalog ,
The replacement of the throttle body and injectors is straight forward and can be done in a few hours , but afterwards you have to tune the bike and do that prefferrably on a dyno while otherwise you are investing a amount of money only to be left with a crappy running bike.
Also be aware of the fact that what comes in must go out so when installing the bigger throttle body the next restriction are the valves so to unleash the whole potential of the bigger throttle body an other camshaft is needed to increase the valve lift and timing , and so you are going from one mod to the next mod and keep on spending money.
By the way ,    There is also a 62 mm Throttle body

A.   SCREAMIN’ EAGLE® PRO HIGH-FLOW 58MM EFI THROTTLE BODY – Electronic Throttle*3
The biggest engines deserve the most fuel. This huge 58mm Throttle Body
won’t leave your engine starving for more air. The one-piece throttle body features Electronic Throttle
Control technology. Just add your stock injectors or the Screamin’ Eagle® Pro High-Flow Injector Kit P/N 27796-08
(sold separately). Stock injectors are recommended for engines making up to 100 rear wheel horsepower, Screamin’
Eagle High-Flow injectors are recommended for engines creating greater than 100 rear wheel horsepower. All
EFI-equipped models require ECM calibration (sold separately). For race application only.

27713-08    $399.95

Screamin’ Eagle® Pro High-Flow Injector Kit - 27797-08 Genuine Harley-Davidson® Product

Injectors provide fuel delivery at the rate of 4.9 grams/second, 25% more than Original equipment injectors. Recommended for use with engine configurations making more than 100 rear wheel horsepower. All EFI-equipped models require ECM calibration (sold separately). For race application only.
Fits Twin Cam models equipped with Screamin’ Eagle 58mm EFI Throttle Body P/N 27713-08

27797-08   $141.00

Hmmmmnnnn....Sounds like this is a mod to consider AFTER my extended warranty runs out in a few years.  Are these items considered part of a Stage 2 upgrade?

[grc]

Speedy, you would be much better off looking at this as a part of a properly planned and coordinated build, and not just a single add-on that by itself isn't going to provide much if any "bang for the buck".  You could throw a TB on there the size of a drain pipe, but it won't do anything good unless the rest of the build can support it.  And unless you make changes that actually allow you to use that extra air flow potential, you don't need to worry about dumping more fuel with bigger injectors.

My advice: Save your money until you decide to do a coordinated build.  And yes, if you are worried about the ESP, don't mess with it until you are willing to assume all risk involved.  The ESP folks have been getting much tighter in recent years.

JMHO - Jerry

[89Speedy]

Speedy, you would be much better off looking at this as a part of a properly planned and coordinated build, and not just a single add-on that by itself isn't going to provide much if any "bang for the buck".  You could throw a TB on there the size of a drain pipe, but it won't do anything good unless the rest of the build can support it.  And unless you make changes that actually allow you to use that extra air flow potential, you don't need to worry about dumping more fuel with bigger injectors.

My advice: Save your money until you decide to do a coordinated build.  And yes, if you are worried about the ESP, don't mess with it until you are willing to assume all risk involved.  The ESP folks have been getting much tighter in recent years.

JMHO - Jerry

Thanks Jerry, good advice indeed!!