ENGINE MODS... Worth it?
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Joined: Jun 2009
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So thats why my bike pulls much better at all rpm's when compared to a stock cam - because 21's are "very similar to stock". Interesting that the specs also dictate that 21's are "very similar to stock"... Even a casual visual inspection with my poor eye sight comparing the two cams tells a different story than yours... lol Not to mention that guys get ~100lbs tq with 21's in 95" with NO headwork.... Sorry, not buyin it 
http://harleytechtalk.net/htt/index.php?topic=11806.0
OP, if nothing else, be sure to do lots of research and on more than one forum if you decide to do a build!
http://harleytechtalk.net/htt/index.php?topic=11806.0
OP, if nothing else, be sure to do lots of research and on more than one forum if you decide to do a build!
A. That dyno graph is a STD, graph meaning its not SAE corrected. So in all likely your pulling peak numbers of around 75hp/90tq.
B. The majority of your gains come from your retune, pipes and AC
C. The 21 cams are VERY MILD and very similiar to stock cams. Your probably only gaining a few foot pounds of torque and hp from just the cams ALONE.
D. The important Andrews cam specs: 10/30 40/08 .473 18 degrees overlap 220/228 duration
Stock: 02/34 42/03 .490 5 degrees overlap 216/225 duration
With the above specs there is NOT MUCH DIFFERENCE between them, very similiar, the 21 will add a bit, but not that much in reality.
Again I have seen big bore 95"/97" kits with stock cams, a good tune, pipes and AC put down a real 90-100 foot pounds of torque(and lower in the RPM range), with a bit more top end power.
THat being said, you do have what looks like a good tune and a very respectable dyno plot, but I have seen better numbers(SAE corrected) from dyno sheets on well tuned 95"/97" setups using stock cams and heads. They have a displacement advantage along with a mild bump of about a point in compression which along offsets a mild cam swapout.
Hell I'll even add that your gaining some hp/tq numbers from the fact that your running SPOKED rims. The reduced rotational mass itself from your wheels will gain your hp and tq. over typical rims that many people run.
Last edited by GunmetalBlueNT; Jul 19, 2009 at 02:11 PM.
Ultimate HDF Member
Joined: May 2008
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From: 'Noke, VA
Hate to burst your bubble, but those are corrected #s....That's what the "SAE 0.99" means.
R.I.P. BROTHER
Joined: Dec 2008
Posts: 3,076
Likes: 6
From: Colorado Springs
I just wanna drool over that 160HP/140TQ Dyno run on Gunnies 114" Train build.....I'm wondering where that big bastard hits. Or where it stops hitting!
I think I would be happy with doing a simple reliable 103 stroker with a fixed up crank that can do 110/120 as any more would have me wadded up in a ditch (One handed jockey shifting at WFO is....Crazy!) but it never hurts to dream a little?
I think I would be happy with doing a simple reliable 103 stroker with a fixed up crank that can do 110/120 as any more would have me wadded up in a ditch (One handed jockey shifting at WFO is....Crazy!) but it never hurts to dream a little?
Banned
Joined: Jun 2009
Posts: 202
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I just wanna drool over that 160HP/140TQ Dyno run on Gunnies 114" Train build.....I'm wondering where that big bastard hits. Or where it stops hitting!
I think I would be happy with doing a simple reliable 103 stroker with a fixed up crank that can do 110/120 as any more would have me wadded up in a ditch (One handed jockey shifting at WFO is....Crazy!) but it never hurts to dream a little?
I think I would be happy with doing a simple reliable 103 stroker with a fixed up crank that can do 110/120 as any more would have me wadded up in a ditch (One handed jockey shifting at WFO is....Crazy!) but it never hurts to dream a little?
Custom spec'd cam grind to my specifications:
Intake Open 17 close 41 .595 lift 238 duration 102 LC 33 degree overlap
Exhaust open 46 close 16 .595 lift 241 duration 105 LC
The cams also used and advance profile with a slow initial opening to maximize intake charge at lower rpms and then open very fast to stop reversion. Allows for excellent punch at low rpms and keeps gunning till my 6200 redline.
Banned
Joined: Jun 2009
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It is not an SAE corrected dynograph. Its a STD graph using the smoothing 5 algorythm. Inflates the numbers.
Road Warrior
Joined: Jul 2008
Posts: 1,426
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From: People's Republik of Kalifornia
Living here in the PRK I think it's worth it because of the continual freeway riding. It is nice to have the extra oomph to pass at 80+MPH. I'm having my X Bones upgraded now. This is a heavy motorcycle (737 lbs) and comparatively slow at freeway speeds. It was fine for around town, and secondary roads, but sometimes out of necessity I have to be on freeways.
R.I.P. BROTHER
Joined: Dec 2008
Posts: 3,076
Likes: 6
From: Colorado Springs
Its over 110 foot pounds of torque at 2k, at sits at over 130 foot pounds from 3k up.
Custom spec'd cam grind to my specifications:
Intake Open 17 close 41 .595 lift 238 duration 102 LC 33 degree overlap
Exhaust open 46 close 16 .595 lift 241 duration 105 LC
The cams also used and advance profile with a slow initial opening to maximize intake charge at lower rpms and then open very fast to stop reversion. Allows for excellent punch at low rpms and keeps gunning till my 6200 redline.
Custom spec'd cam grind to my specifications:
Intake Open 17 close 41 .595 lift 238 duration 102 LC 33 degree overlap
Exhaust open 46 close 16 .595 lift 241 duration 105 LC
The cams also used and advance profile with a slow initial opening to maximize intake charge at lower rpms and then open very fast to stop reversion. Allows for excellent punch at low rpms and keeps gunning till my 6200 redline.
Stop being selfish and greedy.
Post the run.
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Ultimate HDF Member
Joined: May 2008
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From: 'Noke, VA
So in reality, that chart is 0.99 X uncorrected HP & Tq, which means that it's a lower number than uncorrected, and it's got the highest smoothing number, which means that the peaks and valleys are flattened out.
At least that's what the chart says....Since it's not mine, it sure isn't worth bickering over with you.
Banned
Joined: Jun 2009
Posts: 202
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No, it's got an SAE correction factor of 0.99. It's also using the smoothing 5 algorithm, which removes the spikes, and actually serves to lower the numbers.
So in reality, that chart is 0.99 X uncorrected HP & Tq, which means that it's a lower number than uncorrected, and it's got the highest smoothing number, which means that the peaks and valleys are flattened out.
At least that's what the chart says....Since it's not mine, it sure isn't worth bickering over with you.
So in reality, that chart is 0.99 X uncorrected HP & Tq, which means that it's a lower number than uncorrected, and it's got the highest smoothing number, which means that the peaks and valleys are flattened out.
At least that's what the chart says....Since it's not mine, it sure isn't worth bickering over with you.