throttle body size
Thread Starter
|
Cruiser
Joined: Dec 2007
Posts: 127
Likes: 0
throttle body size
I am planning some work on my 07 road king and would like some input.
I am thinking about doing a 103 and upping the compression to 10:1 (any more and I would worry about heat), adding a gear drive cam, doing some head work (that is biting the bullet and buying the SE cnc heads), and going to a 50mm throttle body.
I currently run a pc, rinehart true duals, and a big ole k&n.
My questions are:
It seems like a larger throttle body fits with the increased breathing and fuel input. Does this hammer mileage? Would it be worth it?
It seems like increasing compression is a good way to increase horses and torque. Is heat a real issue - especially on a road king?
Does the gear drive cam make that much difference? I learned that they are supposed to run better and have tighter more reliable tolerances (OK this is what I hear, but I'm not totally sure what that means - are chain drive or stock cams not as reliable?)
Should I upgrade my clutch or wait untill it smokes out?
I really would like to keep near warranty and have had several dealers say they would work with me on these build ideas as long as I would lose the pc if I needed warranty work. I anticipate that my crank bearings will be screaming with this set up so I want to keep in the warranty ball park.
Thanks in advance for the input.
I really love the GMR 107 set up but I am dealing with the warranty issue and was planning on using Harley parts - with reservations.
I am thinking about doing a 103 and upping the compression to 10:1 (any more and I would worry about heat), adding a gear drive cam, doing some head work (that is biting the bullet and buying the SE cnc heads), and going to a 50mm throttle body.
I currently run a pc, rinehart true duals, and a big ole k&n.
My questions are:
It seems like a larger throttle body fits with the increased breathing and fuel input. Does this hammer mileage? Would it be worth it?
It seems like increasing compression is a good way to increase horses and torque. Is heat a real issue - especially on a road king?
Does the gear drive cam make that much difference? I learned that they are supposed to run better and have tighter more reliable tolerances (OK this is what I hear, but I'm not totally sure what that means - are chain drive or stock cams not as reliable?)
Should I upgrade my clutch or wait untill it smokes out?
I really would like to keep near warranty and have had several dealers say they would work with me on these build ideas as long as I would lose the pc if I needed warranty work. I anticipate that my crank bearings will be screaming with this set up so I want to keep in the warranty ball park.
Thanks in advance for the input.
I really love the GMR 107 set up but I am dealing with the warranty issue and was planning on using Harley parts - with reservations.
Outstanding HDF Member
Joined: Apr 2006
Posts: 2,537
Likes: 21
RE: throttle body size
ORIGINAL: roadroids
I am planning some work on my 07 road king and would like some input.
I am thinking about doing a 103 and upping the compression to 10:1 (any more and I would worry about heat)(Huh????), adding a gear drive cam, doing some head work (that is biting the bullet and buying the SE cnc heads), and going to a 50mm throttle body.
I currently run a pc, rinehart true duals, and a big ole k&n.
My questions are:
It seems like a larger throttle body fits with the increased breathing and fuel input(You can only shove 10 lbs of crap in a 10 lb bag, the bigger the TB, the more air the motor has to process... that is a bit large for a 103, and at a desired 10:1 CR, the stock TB can handle it). Does this hammer mileage?(Any mods alter mileage, the ultimate factor is how it is tuned, as to how much your MPG will drop)Would it be worth it?
It seems like increasing compression is a good way to increase horses and torque. Is heat a real issue - especially on a road king?
Does the gear drive cam make that much difference? (New style cam assy are very durable, gear drives are overkill on the new system, but that is my opinion.... Save your $$$, use the chain cams) I learned that they are supposed to run better and have tighter more reliable tolerances (OK this is what I hear, but I'm not totally sure what that means - are chain drive or stock cams not as reliable?)
Should I upgrade my clutch or wait untill it smokes out? (Upgrade the clutch spring and ramp assy)
I really would like to keep near warranty and have had several dealers say they would work with me on these build ideas as long as I would lose the pc if I needed warranty work. I anticipate that my crank bearings will be screaming with this set up so I want to keep in the warranty ball park.(If any dealer says that they will warrenty this whole shebang (Non SE components), they are only warrenting the CRAFTSMANSHIP, they cannot warrent the components... as an example, if you drop a valve out of the SE heads, well, they are going to eat it, as there is no way that they can submit it to HD for reimbursement, seeing as they are "FOR RACE USE ONLY", if you pushed the issue, because something failed on a road trip, HD will send out a Service rep, and as soon as they would see the true duals, K&N ac unit, anything non-HD, they have the right to deny the claim... I am NOT saying that this will happen, but IF your CHOSEN dealership will honor their CRAFTSMANSHIP, then go for it, but remember if something happens when you are way far from the homestead, any other dealer doesn't have to do the same... Seen it quite a few times, and it ain't pretty....)
Thanks in advance for the input.
I really love the GMR 107 set up but I am dealing with the warranty issue and was planning on using Harley parts - with reservations. (Again, even if you used ALL H-D parts, some components are not warrentable, as they are "Race Use Only", and not sublect to the same warrenty criteria as your OE components)
I am planning some work on my 07 road king and would like some input.
I am thinking about doing a 103 and upping the compression to 10:1 (any more and I would worry about heat)(Huh????), adding a gear drive cam, doing some head work (that is biting the bullet and buying the SE cnc heads), and going to a 50mm throttle body.
I currently run a pc, rinehart true duals, and a big ole k&n.
My questions are:
It seems like a larger throttle body fits with the increased breathing and fuel input(You can only shove 10 lbs of crap in a 10 lb bag, the bigger the TB, the more air the motor has to process... that is a bit large for a 103, and at a desired 10:1 CR, the stock TB can handle it). Does this hammer mileage?(Any mods alter mileage, the ultimate factor is how it is tuned, as to how much your MPG will drop)Would it be worth it?
It seems like increasing compression is a good way to increase horses and torque. Is heat a real issue - especially on a road king?
Does the gear drive cam make that much difference? (New style cam assy are very durable, gear drives are overkill on the new system, but that is my opinion.... Save your $$$, use the chain cams) I learned that they are supposed to run better and have tighter more reliable tolerances (OK this is what I hear, but I'm not totally sure what that means - are chain drive or stock cams not as reliable?)
Should I upgrade my clutch or wait untill it smokes out? (Upgrade the clutch spring and ramp assy)
I really would like to keep near warranty and have had several dealers say they would work with me on these build ideas as long as I would lose the pc if I needed warranty work. I anticipate that my crank bearings will be screaming with this set up so I want to keep in the warranty ball park.(If any dealer says that they will warrenty this whole shebang (Non SE components), they are only warrenting the CRAFTSMANSHIP, they cannot warrent the components... as an example, if you drop a valve out of the SE heads, well, they are going to eat it, as there is no way that they can submit it to HD for reimbursement, seeing as they are "FOR RACE USE ONLY", if you pushed the issue, because something failed on a road trip, HD will send out a Service rep, and as soon as they would see the true duals, K&N ac unit, anything non-HD, they have the right to deny the claim... I am NOT saying that this will happen, but IF your CHOSEN dealership will honor their CRAFTSMANSHIP, then go for it, but remember if something happens when you are way far from the homestead, any other dealer doesn't have to do the same... Seen it quite a few times, and it ain't pretty....)
Thanks in advance for the input.
I really love the GMR 107 set up but I am dealing with the warranty issue and was planning on using Harley parts - with reservations. (Again, even if you used ALL H-D parts, some components are not warrentable, as they are "Race Use Only", and not sublect to the same warrenty criteria as your OE components)
Sponsor
Joined: Dec 2007
Posts: 12,084
Likes: 829
RE: throttle body size
We have had stellar results with boring the 2-piece Delphi's on 103" touring builds. Think about this. They land at 46.5 mm when copmpleted. High velocity= big cylinder fill=big power. Bigger is better, when bigger is needed.
Outstanding HDF Member
Joined: May 2007
Posts: 2,304
Likes: 31
From: Florida
RE: throttle body size
I agree with Bob but I will add one more thing...the CNC SE heads are not a good choice on a 103' by far. There are many porters out there that are good, Hillside, Baisley, HQ,SBC,and so on,and will serve your needs much better (more bang for the buck) than the off the shelf heads. The `07 Stock TB will be fine for your 103' also.
Road Warrior
Joined: Nov 2007
Posts: 1,984
Likes: 7
RE: throttle body size
You can look at a stock TB and see how it can be improved a little. Mine was cleaned up and then flowed. The numbers, at whatever pressures, went from 200 to 240. So 15-20 percent. Plenty for a nice build 103. Now that is just a cleanup not a bore out. I'd go to Zippers TB for major increase if I did that.
And I used the stock chain cam drive.
And I used the stock chain cam drive.
Intermediate
Joined: Feb 2008
Posts: 30
Likes: 0
RE: throttle body size
A larger throttle body isn't going to hurt your mileage, a cam that will support a 10:1 compression ratio will.There isn't really a downside to a larger throttle body, it doesn't rely on a vacuum signal like a carb, and won't have issues like a bike with a big carb on it."Velocity" in the throttle body isn't a problem.The new chain and tensioner setup on your bike looks to be far superior to the old spring loaded tensioners,(although only time will tell)I'd probably stick with them and save the money.I agree with Doc 1 that you'd be better off having someone work with your stock heads, and leave the SE's on the shelf.JMO
Trending Topics
Road Master
Joined: May 2007
Posts: 851
Likes: 5
From: Mitchellville, Ia.
RE: throttle body size
I agree with much of what has been said and have experienced the SE head issues many times with many people who installed the heads and were not satisfied with the results and agree that the factory warranty is no reason to stick with those heads when you can rework the stock heads and pull 20-40 degrees out of the engine and have more linear torque than with the SE parts. One of the head mods I use chokes the ports down 30% and revs much quicker and sometimes even runs cooler yet.I use the HPI TB's because as stated the larger body does not hinder performance or milege and the effect of the larger intake manifold volume helps also. I have not had the chance to test the bored outbody yet and would like to know more about this before I try it.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
6 Weirdest Harley-Davidsons Ever Sold to the Public
Verdad Gallardo
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
Outstanding HDF Member
Joined: Jul 2006
Posts: 2,303
Likes: 4
From:
RE: throttle body size
For a street machine the stock TB for a 96/103 is big enough,I would bet that whatever increase you seen in performance wouldnt be worth the cost.Im sure your bike isnt ridden at edge of rev limiter enough to even see what little improvement there might be.Upgrade your own heads if nothing else ,the so-called reps will have to see bike while its apart to see warranty dispute.Use HDs compliant cams or kiss the warranty away!Honoring warrantys belyond HDs limits may bite you no matter what dealers says NOW.Finding a dealer away from home would be even harder.Keep in mind these cranks have be known to scissor and upping performance w/o correcting this issue increases your chances.Two real chices,build it right correcting the lwr end,your choice of parts,engine size,exh,TB,tuner etc...or use HDs parts and keep the warranty until expired.
Road Warrior
Joined: May 2006
Posts: 1,479
Likes: 4
From: SoCal
RE: throttle body size
If you have the $$$ (How about $625?) you can get SE High-Performance heads, have them ported and see great hp gains vs. stock head porting. I'm more than stoked that I bought the SE heads rather than having my stock heads worked. Check out the dyno chart here: http://www.trirycheracing.com/HendersonPerf.pdf
I wouldn't bore the TB on your Delphi, for street use I agree they'll flow plenty of air.
I wouldn't bore the TB on your Delphi, for street use I agree they'll flow plenty of air.