Good day guys, need your help and experience to consider a possible engine upgrade.

I’m talking about the Screamin’ Eagle 50mm Throttle Body p.n. 27623-05A.

My 2014 Breakout has SE-204 cams and the stock 46mm TB and was wondering how the bike would change using a 50mm TB. I know the more common mod after cams is CNC machined cylinder heads but before doing these would prefer something less invasive and cheaper. As far as I found surfing the net in terms of dyno sheets there’s a slight difference in hp/tq between stock 103” engines using 46mm and 50mm TB, but still a difference.

Just consider that m.y. 2016 Softail lineup has the 50mm TB as stock…therefore they called High-Output 103”…

The cost-effectiveness analysis is $500 for TB and new matching 50mm Stage I AC kit for a final gain in terms of 3 or 4 HP/TQ, after a good dyno, with a sensible responsiveness increase.

But here are my doubts. Will this TB fit on my 2014 BO? Catalog description is a little unclear, in particular on the intake flanges. Obviously making this mod but having a “bottle neck” on intake is useless.

So I checked micro fiches of 2014 and 2016 models. Stock cylinder heads and flanges are exactly the same so, having the 2016 a 50mm TB, this shouldn’t be a “bottle neck”.

Here’s my question. Will this TB fit my engine using the flanges supplied with the kit or reusing stock ones?

Here’s thecatalog description.

Any help would be highly appreciated since my mechanical skills and knowledge already reached my limits…



Higher flowing for larger displacement race engine applications.

Includes throttle body and unique intake flanges and

seals. This big bore throttle body features a 50mm throttle

plate (a 4mm increase over the ’06 Original Equipment throttle

body) to provide increased airflow and more power.Higher

flow rate injectors provide 25% more fuel to complement the

increased airflow. Sensors, injectors (with a flowrate of 4.9

grams/second) and the IAC stepper motor are fully assembled

on this bolt-on unit. All EFI-equipped models require ECM

calibration (priced separately). For race application only.

27623-05A $399.95

Fits ’06-later Twin Cam EFI models (except ’08-later

Touring) equipped with accessory performance cylinder

heads. The intake flanges supplied in this kit will only fit

cylinder heads machined for use with the stock symmetrical

intake flanges (Original Equipment since MY06). All Screamin’

Eagle® performance cylinder heads (except Kompressor and

MCR Performance) with kit P/N extension of -06 orlater have

a intake port diameter of 1.750" and are machined for use with

symmetrical intake flanges.

 

C'mon, I know there are a lot of tech gifted brothers among us!

 

From what I understand, using a bigger throttle body (and/or injectors) will give better HP numbers on the higher rpm range but will hurt lower rpm range due to too much fuel if the motor doesn't have sufficient capacity to move air in equal amounts.

Sometimes smaller is better.

 

Not necessarily, at least as far as I understood. Obviously if Throttle Body is oversized the result is what you stated but in this case, analyzing some dyno sheet, the performance increase is on all ranges and both on hp/tq.
I believe these sheets also due to the fact that 2016 Softail lineup has 50mm throttle body with exactly the same motor...and is called High Output being the changes only on tb and cams...
That's why I was wondering what would be the increase of this tb over a 103"B with SE-204 cams...
Obviously a good dyno would be necessary to optimize everything.

 

I'm already running 204 cams and thinking about the 50mm TB. Did you get any info on this?

 

2016 softail have 50 mm TBW
your 14 is a cable throttle

 

All depends on what you are wanting to accomplish. Looking at dyno charts does not give a full story. Those runs are made at wide open throttle under a controlled load and environment. They will not truly reflect real world drive ability. Having said that the 2016 is also throttle by wire and yes it runs a larger TB. They can play with the settings on the throttle to make it more responsive given load and other factors.

I know the 204 cam is a great mid cam but honestly $500 is better spent on the gearing change. You will get much more bang for the buck in changing to a 30/70 than you will ever see from a TB with that mild of a cam

 

Dude, the original post is more than one year old....and the cams have already been installed long ago....with great improvement of the overall performance, AFAIK and so has the TB

And BTW....considering all costs implied for the 30/70T drive sprocket change you will more likely end up with $ 1K...

 

A bigger throttlebody does not add more fuel, it only provides more air. The injectors supply the fuel. The bigger throttlebody will help a bit in peak numbers and will not necessarily hurt down low like an oversized carb would.
To the OP... Unless I missed it, I did not see where you upgraded your exhaust. If not, a new exhaust would be your best bang for the buck.
Edit: Wow this is an older thread...oops

 

Well I guess we might as well make an old post current and relevant for anyone else who reads it

I looked into the SE 50mm TB and I believe it only fits the SE heads- I could be wrong, but there is no way to confirm if it fits stock heads.

What I'm doing now is, I picked up a nice condition used 46mm TB off ebay for $50. I picked up a set of 4.9 SE injectors for $100. I'm having George at maxbore.com hog the TB out to 50mm or 51mm and cut a new butterfly, $125 total.

Main reason I am doing this is my current stock 3.9 injectors are maxing out at 100% duty cycle under high MAP and mid to upper rpms. that is bad for tuning accurate fuel delivery as it should always be kept under 85% max IDC. And since I'm swapping injectors I might as well pop on a slightly larger TB for not much added effort or expense.
Right now, the 46mm TB flows less than the stock heads, so a 50/51mm is not "too big" at all in this situation, it's actually more appropriate and correct of a size for the 103. I'll be adding a 204, 54, 57 set of cams later on (one of those or similar mild cam, TBD).

But- if we are talking straight "bang for buck", as mentioned the 30/70 pulley upgrade would give much more immediate performance benefit vs a mild cam and TB upgrade. Even though it's well higher in cost. Doing both of these upgrades though, will work together beautifully. It's actually a rather economical spend of est. $1300 total for a lot of added grunt.

You do however need a powervision, fp3, tts or similar tuner to be able to dial everything in and also set the speedometer correction correctly for the pulley changes.- that's another $300-$500.

But hey- What's almost a couple grand on Harley performance upgrades? Chump change right? LOL