HOW BIG OF TB DO YOU NEED FOR YOUR MOTOR? INFO HERE.......

[GoFast.....]

I was doing some research for my 107 and got some reliable info on cfm TB, This is what I like about HTT and the willingness of everyone to share what they know and learn. The TB is sometimes the reason why no matter what you do to your bike you can't get it to run bigger numbers

01-05 TB  184cfm

This Tb is 44mm
but chokes down
to a 38mm behind
the 44mm plate

06-07 TB  217cfm

08- 09 touring models
have 50mm which will
add a little more but
the rest will be like
the 06-07

Screamin  232cfm
eagle

YourStock 246cfm
TB modifed HPI
200.00 PRICE

HPI 51 TB 253cfm
(will out flow a 58
WT TB) 10% off now
The flow changes the bigger
the intake ports are like
1.710 and 1.8

For Most GUYS wanting more over 100hp Sending your TB to HPI for 200.00 is some of the best money you will spend.

http://www.horsepowerinc.net/products/big-bore-throttle-bodies/



HPI 51 AND 07 STOCK TB

[Admiral Akbar]

So where dis you get the data from? What pressure? Max.

[JAFHR]

How can I tell if I have the 50 or other TB on my 08 Ultra. Are you saying that I can send my TB in and have it modified to a larger diameter for $200. How does this differ from buying one of there's?

[ViennaHog]

How can I tell if I have the 50 or other TB on my 08 Ultra. Are you saying that I can send my TB in and have it modified to a larger diameter for $200. How does this differ from buying one of there's?

The 2008 - touring models all have the 50 mm TB, it's a part of the FBW throttle system. All other TC TBs remain unchanged from 2007 AFAIK

[wfolarry]

Sending out a 1 piece [late style] throttle body for any work is a total waste of money. If you need more power put that money in a piggy bank & save up some more & do it right.

[Admiral Akbar]

"after this post Eric should have a 100 of them to do."

Should also ask. Do you get a cut? Max

[Flat Dog]

With all due respect, I've still not seen a group of engineers use flow testing to PROVE that larger or modified venturi throttle bodies will increase the amount and quality of the charge introduced into the air pump on a normally aspirated engine. I am not saying it's not true, but I still haven't seen anyone PROVE beyond a doubt that it is true. Engine building is science, not voodoo.

All I see are dyno sheets showing me nothing-no comparisons, no explanation of HOW these modified TBs are making more HP, etc. Heck-it's a shuck and jive job so far. Prove to me that your product works-don't just tell me it's popular on the internet. So is donkey porn.

If I am wrong, I am more than happy to eat my words and apologize.

[se]

we have seen a 3-5 hp diffrence with a Bored T/b.
the motor was a 95 in, woods tw6g, 10.1 compression, and baisley heads.
a lot of money for little return.
.

[GoFast.....]

we have seen a 3-5 hp diffrence with a Bored T/b.
the motor was a 95 in, woods tw6g, 10.1 compression, and baisley heads.
a lot of money for little return.
.

There is a diffrence between a bored TB and a Modifed TB. The Modifed has porting work done to it

[GoFast.....]

"after this post Eric should have a 100 of them to do."

Should also ask. Do you get a cut? Max

I wish I got a cut. HPI has probably the best afthermarket TB out there and has done extremely well on the dyno with people like Larry, Mike and many others on HTT

[GoFast.....]

With all due respect, I've still not seen a group of engineers use flow testing to PROVE that larger or modified venturi throttle bodies will increase the amount and quality of the charge introduced into the air pump on a normally aspirated engine. I am not saying it's not true, but I still haven't seen anyone PROVE beyond a doubt that it is true. Engine building is science, not voodoo.

All I see are dyno sheets showing me nothing-no comparisons, no explanation of HOW these modified TBs are making more HP, etc. Heck-it's a shuck and jive job so far. Prove to me that your product works-don't just tell me it's popular on the internet. So is donkey porn.

If I am wrong, I am more than happy to eat my words and apologize.

Increaseing TBs has been proven to increase HP on normally aspirated Highperformance Car engines some many times it's not even worth talking about it. Words are hard to eat. Here's some popcorn

[Quick_2s]

Can going to large for your motor hurt you the same as under sizing it? 

[grnrock]

I found my 06 TB Produced 124hp on my 103.I do have a 57mm but sheeeeeeeeeeeeeee run's so fine.mpg is 43@3k
Bill

[tireater]

So HPI can modify my stock 06 T.B. and get me 246 cfm...for $200..right?

[mtnmotorrider]

You guys that don't like the one piece TB on '07's, can you explain what the difference is from the earlier one piece models?  Is it runner design, length, what?  And can an earlier two piece modified by a compedent company be retro fitted to an '07?

[Flat Dog]

Can going to large for your motor hurt you the same as under sizing it? 

Most definitely. A too large TB can cause off the line bogging, tuning nightmares, etc...


Again-no disrespect to the OP or HPI, but as stated-a 2-3HP gain is big stuff at the track, but show me the under redline usable street torque/hp large curve improvement for that 6-700 bucks. I'll eat my popcorn while waiting. I bet I am going to get really fat... That's a lot of money to some people for a tiny little gain.

Yeah, cars have used large CFM double pumper bla bla bla carbs for years, but most of the time it's overkill done by ignorant 'bigger is better' types that haven't really done the math.

[se]

we have seen a 3-5 hp diffrence with a Bored T/b.
the motor was a 95 in, woods tw6g, 10.1 compression, and baisley heads.
a lot of money for little return.
.

There is a diffrence between a bored TB and a Modifed TB. The Modifed has porting work done to it

have not had the opportunity to hear about the modified results but i know if we could send one out i think it is going to Dan Baisley. i beleive he is doing a modified one am i correct as HPI..
i can only speak for what i have saw on the dyno now if you were doing a few other changes such as trying diffrent cams and exhasuts you will most likely see more of an increase then 2-3. 

[se]

Can going to large for your motor hurt you the same as under sizing it? 

Most definitely. A too large TB can cause off the line bogging, tuning nightmares, etc...


Again-no disrespect to the OP or HPI, but as stated-a 2-3HP gain is big stuff at the track, but show me the under redline usable street torque/hp large curve improvement for that 6-700 bucks. I'll eat my popcorn while waiting. I bet I am going to get really fat... That's a lot of money to some people for a tiny little gain.

Yeah, cars have used large CFM double pumper bla bla bla carbs for years, but most of the time it's overkill done by ignorant 'bigger is better' types that haven't really done the math.

with my 120 build we went from a 55mmhpi to a 58/62 hpi. seen a 1-1 gain all the way to the end overlayed the graphs and it was identical just 1hp 1tq higher of a diffrence...
let me get you another bag.......

[Faast Ed]

All I see are dyno sheets showing me nothing-no comparisons,

Here are some comparisons posted just tonight on this board:


http://harleytechtalk.net/htt/index.php?topic=1125.0  (2 into 1 pipe string)

[se]

All I see are dyno sheets showing me nothing-no comparisons,

Here are some comparisons posted just tonight on this board:


http://harleytechtalk.net/htt/index.php?topic=1125.0  (2 into 1 pipe string)

Thanks Ed.

[FLTRI]

But George,
There is a +or- 2hp/tq error in these dynos. So a 1-1 improvement, I think would = 0? 
Bob

[Faast Ed]

I was waiting for someone to say that Bob! 

From one run to the next, you can have that difference without even touching the motor.

[se]

well Bob im sure if i brought it to you you could get better # out of it maybe you could get the +2 out of it for me.
what do you think it was just swapped out and the afr tuned in and then run.
tried that could not get the low speed hesitation tuned out
with that t/b the whole map had to be redone.
but then again Bob you knew that.

oh yes 1 other thing also we tried tuning the motor in the same conditions as the previous day just incase that was your next dig

[skyhook]

I like hpi, got me 11 hp vs stock tb & injectors...latus motors soon to have variable venturi fly by wire, already have cable operated...my friend al is developing dual throat

[Flat Dog]

Thanks skyhook!