The Sportster and Buell Motorcycle Forum - The XLFORUM®
 

Go Back   The Sportster and Buell Motorcycle Forum - The XLFORUM® > SPORTSTER MOTORCYCLE FORUM > Sportster Motorcycle Motor / Engine > Sportster Motorcycle Motor - Top End
XLF Blogs XLF Arcade XLF Disclaimer/Privacy Statement/Terms Of Use

Notices

Sportster Motorcycle Motor - Top End Discuss Sportster Motorcycle Top End issues. Rockerboxes, Valves, Cylinders, Pistons, Rings, Lift Rods, etc...

Active Threads
0 Keep & Kill
Last Post: Sporty1989
Posted On: 15 Minutes Ago
Replies: 31,568
Views: 1,864,571
0 Sportsterpedia Progress
Last Post: Hippysmack
Posted On: 50 Minutes Ago
Replies: 380
Views: 121,980
0 Belt tension
Last Post: RandallM
Posted On: 2 Hours Ago
Replies: 11
Views: 155
0 Rear pulley inner flange
Last Post: IXL2Relax
Posted On: 3 Hours Ago
Replies: 7
Views: 153
0 Official XL Forum Random Image Thread (NO NUDITY!)
Last Post: Graywolf
Posted On: 6 Hours Ago
Replies: 55,634
Views: 9,526,957
0 Snippets
Last Post: Crusty
Posted On: 6 Hours Ago
Replies: 781
Views: 120,466
0 winding idle up excessively to start bike.
Last Post: 1Scooter
Posted On: 6 Hours Ago
Replies: 68
Views: 4,163
0 What did you do for your sporty Today?
Last Post: Graywolf
Posted On: 6 Hours Ago
Replies: 8,058
Views: 1,523,102
0 Anyone go racing last weekend?
Last Post: wrkdWS6
Posted On: 7 Hours Ago
Replies: 3,426
Views: 414,548
0 Sportster Oil Pressure and Dynamics
Last Post: Hippysmack
Posted On: 8 Hours Ago
Replies: 458
Views: 37,479
0 Bulb Wattage
Last Post: bustert
Posted On: 10 Hours Ago
Replies: 2
Views: 162
0 1981 Sportster Won't Shift Into 4th
Last Post: brucstoudt
Posted On: 11 Hours Ago
Replies: 23
Views: 1,230
0 shift fork source?
Last Post: brucstoudt
Posted On: 11 Hours Ago
Replies: 6
Views: 224
0 Food porn
Last Post: Stairman
Posted On: 12 Hours Ago
Replies: 2,910
Views: 771,235
0 Therapy:
Last Post: Tomcatt
Posted On: 14 Hours Ago
Replies: 1
Views: 113
0 Brake pedal won't activate brake light
Last Post: Tomcatt
Posted On: 17 Hours Ago
Replies: 39
Views: 2,178
0 Latest toy arrived... 1967 Sportster XLB
Last Post: thefrenchowl
Posted On: 17 Hours Ago
Replies: 42
Views: 3,321
0 Harbor Freight
Last Post: ChinCactus
Posted On: 18 Hours Ago
Replies: 12
Views: 414
0 Hottie of the day, no nudity.
Last Post: Stairman
Posted On: 20 Hours Ago
Replies: 39,498
Views: 5,170,824
0 HD announces end of the Sportster model
Last Post: Sporty1989
Posted On: 1 Day Ago
Replies: 38
Views: 1,543
0 Something different: 1948 Willys Truck
Last Post: XL Ed
Posted On: 1 Day Ago
Replies: 71
Views: 10,239
0 Cylinder Heads
Last Post: Steve9
Posted On: 1 Day Ago
Replies: 56
Views: 3,827
0 Rotors hot, brakes dragging
Last Post: epswing
Posted On: 1 Day Ago
Replies: 38
Views: 1,544
0 What jets do you use?
Last Post: Thack
Posted On: 1 Day Ago
Replies: 245
Views: 93,114
0 Hot Rods, Rat Rods, and Customs.
Last Post: Stairman
Posted On: 1 Day Ago
Replies: 5,482
Views: 1,279,943
5 Are you married or single???
Last Post: Akdawg
Posted On: 1 Day Ago
Replies: 542
Views: 81,896
0 How many miles do you have on your rubbermount?
Last Post: sportsterpaul
Posted On: 1 Day Ago
Replies: 516
Views: 126,686
0 Roads I'd like to ride.
Last Post: Stairman
Posted On: 1 Day Ago
Replies: 3,905
Views: 498,877
0 Rear caliper squeaks and squeals: HELP!
Last Post: canoli
Posted On: 1 Day Ago
Replies: 10
Views: 237
0 Another transformation coming
Last Post: Sporty1989
Posted On: 2 Days Ago
Replies: 4
Views: 389
More...
Members Birthdays
moe (78), demgdaj (72), Playtoe (67), shanneba, Charlie Allen (63), the cowboy way (63), P-Diddly (60), Utahsporty (59), evo-pete (58), stf420 (57), NevadaRob (55), Punisher (53), Razor_Reznor (48), Paycheck (45), jfs92579 (43)
Reply
 
Share Thread Tools Display Modes
  #1  
Old 10th July 2022
DrMotorcycle DrMotorcycle is offline
Biker
 
Join Date: Apr 2022
Posts: 31
Sportster/Buell Model: Sportster
Sportster/Buell Year: 1994
Reputation: 145945
DrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant future
Default Cams for a Turbo XL1200H

Well, I've had my Draw-Thru turbo Sportster on 12PSI of boost w/mechanical water/methanol injection for the past month or so and I'm already bored . Check my post history for more information on the bike. A quick summary is it's a Draw-Thru Turbo Setup, HSR42 w/dual thunderjets (one is pump gas, the other is 50/50 water methanol), and a T25/T28 Hybrid Turbo W/Carbon Seal.

Anyways, I knew I'd be at the point of wanting more power pretty quickly coming from (180hp) sportbikes, so I started looking around at the current cam offerings from all of the different companies. Seems to me that if I were to keep it simple, the Fueling Reaper 505/515 is the best all around choice; They can be bolted straight in, they have very mild overlap (26*), 108.5/109 lobe centers, and a 239/248 split duration; is it me, or does this seem like it was almost meant for a turbo setup? Strongly leaning this direction right now.

Andrews n4/.497 SE's Seem too aggressive on the Overlap + Duration for a Turbo setup, N2/N3 Give up too much lift in comparison to the Fueling 505/515, and every other cam past the .500 lift range is going to take some headwork to not be a waste of time (correct me if I'm wrong).

What says you?
Reply With Quote
  #2  
Old 23rd July 2022
Turbo Sporty 48 Turbo Sporty 48 is offline
Senior Master Custom Bike Builder
 
Join Date: Sep 2010
Posts: 3,568
Sportster/Buell Model: XL1200X Turbo 48
Sportster/Buell Year: 2011
Sportster/Buell Model #2: XL1200 Roadster
Sportster/Buell Year #2: 2008
Turbo Sporty 48 has disabled reputation
Default

Check out the 551 cams.
Buel made them Harley adopted them, I think.
Best turbo cam for the money.
Reply With Quote
  #3  
Old 24th July 2022
aswracing's Avatar
aswracing aswracing is offline
A Million Facts & Figures
 
Join Date: Jan 2005
Location: Famous Potatoes
Posts: 10,413
Sportster/Buell Model: XL883
Sportster/Buell Year: 2007
Sportster/Buell Model #2: Buell Cyclone
Sportster/Buell Year #2: 1999
Reputation: 3863417
aswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond reputeaswracing has a reputation beyond repute
Default

Quote:
Originally Posted by DrMotorcycle View Post
Well, I've had my Draw-Thru turbo Sportster on 12PSI of boost w/mechanical water/methanol injection for the past month or so and I'm already bored . Check my post history for more information on the bike. A quick summary is it's a Draw-Thru Turbo Setup, HSR42 w/dual thunderjets (one is pump gas, the other is 50/50 water methanol), and a T25/T28 Hybrid Turbo W/Carbon Seal.

Anyways, I knew I'd be at the point of wanting more power pretty quickly coming from (180hp) sportbikes, so I started looking around at the current cam offerings from all of the different companies. Seems to me that if I were to keep it simple, the Fueling Reaper 505/515 is the best all around choice; They can be bolted straight in, they have very mild overlap (26*), 108.5/109 lobe centers, and a 239/248 split duration; is it me, or does this seem like it was almost meant for a turbo setup? Strongly leaning this direction right now.

Andrews n4/.497 SE's Seem too aggressive on the Overlap + Duration for a Turbo setup, N2/N3 Give up too much lift in comparison to the Fueling 505/515, and every other cam past the .500 lift range is going to take some headwork to not be a waste of time (correct me if I'm wrong).

What says you?
Proper cam selection for a turbo setup starts with understanding the turbo's differential pressure ratio, i.e. how much exhaust pressure is needed to generate how much intake pressure.

Very inefficient turbos have a ratio of 2:1 or greater. You have to really limit the overlap in that situation. But the closer you get to 1:1, the more the cams can start looking like normally aspirated cams. Read Vizard's books, he goes into more detail on all this.

Stock 1994 XL1200 heads (if that's what you're running) nose over on the flow bench by the time you reach .450 of lift. In other words, the valve is far enough out of the way that it's no longer the thing that's constraining the flow. You can continue to lift it farther, but the flow won't increase.

To take advantage of high lift you need bigger valves. Big valve heads, with good ports and a valve job that pushes the valve size, can be set up such that the flow doesn't nose-over until north of .600 lift. That's when it makes sense to use high lift cams.
__________________
Click Here to Contact Me

Reply With Quote
  #4  
Old 2 Days Ago
DrMotorcycle DrMotorcycle is offline
Biker
 
Join Date: Apr 2022
Posts: 31
Sportster/Buell Model: Sportster
Sportster/Buell Year: 1994
Reputation: 145945
DrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant futureDrMotorcycle has a brilliant future
Default

Quote:
Originally Posted by aswracing View Post
Proper cam selection for a turbo setup starts with understanding the turbo's differential pressure ratio, i.e. how much exhaust pressure is needed to generate how much intake pressure.

Very inefficient turbos have a ratio of 2:1 or greater. You have to really limit the overlap in that situation. But the closer you get to 1:1, the more the cams can start looking like normally aspirated cams. Read Vizard's books, he goes into more detail on all this.

Stock 1994 XL1200 heads (if that's what you're running) nose over on the flow bench by the time you reach .450 of lift. In other words, the valve is far enough out of the way that it's no longer the thing that's constraining the flow. You can continue to lift it farther, but the flow won't increase.

To take advantage of high lift you need bigger valves. Big valve heads, with good ports and a valve job that pushes the valve size, can be set up such that the flow doesn't nose-over until north of .600 lift. That's when it makes sense to use high lift cams.
Thanks for the advice. I told my Uncle to give you guys a call about a motor that he's putting together for his Buell S1 that threw a rod. He's doing a (I think?) 90" setup on it and I think I recall that he said he's going to have you guys do the bottom end.

There were some Redshift 585's on ebay that I sent him a link to, as we often do for each other when we see good deals. He bought them . Said he talked with someone at Hammer and Ordered Springs and Adjustable's w/collapse-able tubes IIRC.

I digress. The reason I bring this up is that he also owns an M2 cyclone that he Nicknamed "Psiclone" that has one of my draw-thru turbo setups on it. Since he bought the 585 cams, he now has a set of .497's that were in the S1 as original equipment that need a new home. Pretty sure the plan as of now is for him to pull out his 497's and have me install them in his M2 while I'm doing a top-end gasket swap (bike has 67k miles!). He mentioned wanting to possibly install a set of low-comp turbo pistons, IDK if you have a drop-in solultion or not.


So long story short, I'll be testing the N4's pretty soon on the Turbo Buell M2 fairly soon.
Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT +1. The time now is 08:32.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.
XL Forum® - Linson Media LLC