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Resist Tyranny
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Discussion Starter #1
2008 FXDF, SE Heavy Breather, D&D FatCat and PCV. I rarely ride 2 up, probably ride too fast, run in the upper RPM range more than just putting and make an occasional run down the 1320. Somewhere in the future I want to do a 106 kit with head work, maybe way in the future. I want enough cam for 10.5 but not too much for stock compression. I have been looking at the Andrews 37H chain drive but the shop is really pushing the S&S 570 easy start gear drive. It's about 5 c notes difference. Are the advantages of the gear drive system worth the extra scratch? Will the longer duration of the 570s kill my cylinder pressure? Will the 37H need compression release if I ever boost the CR Thoughts? Opinions? Experience with either cam?

later, dozer

p.s. I appreciate any and all input
 

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2007 & up cranks have large run out (wobble), and are usually not good candidates for gear drive cams. The cranks are also susceptible to scissoring when subjected to high loads (tq/hp). Many performance builds have the cranks welded to prevent scissoring.
 

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2008 FXDF, SE Heavy Breather, D&D FatCat and PCV. I rarely ride 2 up, probably ride too fast, run in the upper RPM range more than just putting and make an occasional run down the 1320. Somewhere in the future I want to do a 106 kit with head work, maybe way in the future. I want enough cam for 10.5 but not too much for stock compression. I have been looking at the Andrews 37H chain drive but the shop is really pushing the S&S 570 easy start gear drive. It's about 5 c notes difference. Are the advantages of the gear drive system worth the extra scratch? Will the longer duration of the 570s kill my cylinder pressure? Will the 37H need compression release if I ever boost the CR Thoughts? Opinions? Experience with either cam?

later, dozer

p.s. I appreciate any and all input

That S&S .570 likes 10.1 cr.
Good cam.
Scott
 

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Lost in Space
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I have tw7h cams on my king, were there when I bought her. Know nothing about them.
 

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Resist Tyranny
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Discussion Starter #8
The cam upgrade project is complete. Decided to go with Andrews 37H chain drive, replaced the hydraulic tensioners, lifters, push rods also. Harley dealer didn't sound very confident or knowledgeable when I quizzed them about dyno tune so I chose an Indy shop, with a shelf full of trophies, that runs three drag bikes (a Dyna, an iron head Sportster and some jap bike) and a road racing bike. They convinced me to delete the PCV and go with a system cal Direct Link: https://technoresearch.com/index.php/products/tuning/harley-davidson. This is not an add on but unlocks the ECM and reconfigures it's settings. Truly amazing what the Delphi system is capable of. I will post the dyno results in the appropriate thread if your interested. The numbers are a little lower than I expected but the mech told me that was due to the shop using a Superflow dyno instead of a Dynojet and it figures the corrections differently, said a Dynojet would read about 12% higher. Feels good, slight lope at idle, excellent throttle response, good roll on power, no decel popping, haven't checked mileage yet, only 80 miles so far. I'll post a time slip when I get one.

later, dozer

p.s. http://www.harley-davidsonforums.com/forums/classified-sale/232562-sale-power-commander-v-06-11-dyna.html
 

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The 37 is the T/C counterpart of the Evo 27. Good cam.
We use a lot of 57's now under the springs you have.
High-lift version of the 37 with a slightly tweaked exhaust.:)
Scott
Scott
 

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Resist Tyranny
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Discussion Starter #12
Well it's been a little over two years since I upgraded the cams. I must say that I'm somewhat disappointed in the performance of this cam. For the cost of the swap I was expecting a bigger increase in power. I think I made a mistake in not going with more cam. I rarely ride two up and my riding style is more toward the performance end of the spectrum as compared to just cruising. I'm considering a change to S&S 585 cams for a winter project. I wish I could afford upgrading to an S&S 106" kit at the same time but I doubt if that will happen. I listened to some people who advised me against going with "too much cam". I started out wanting the 585s and that's what I should have gone with.

later, dozer

p.s. some day I will learn to listen to my own advise
 

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Just adding cams to stock cubes, stock heads and stock compression is not a mod that is going to blow you away in terms of added power. It doesn't matter what cams you use.

The only thing worse than adding a cam and not getting expected power gains is swapping out that cam for another one and ending up in the same boat. Do you really want to rip the bike apart for what might be 2-3 ft. lbs of torque improvement? I don't think the butt dyno is going to register much change with that one.
 

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I agree...cams alone won't give you what you want! I went to 107ci, carillo pistons at 10.75:1 cr, CNC ported and flowed heads and S&S MR103 easy start cams (585 lift) chain driven, S&S high performance lifters, S&S adjustable push rods...already had SE high flow air cleaner and V&H true duals with RC Componet mufflers. If I want even more power I can add a 2 into 1 D&D exhaust, dual head air intake and a 58mm throttle body with larger injectors. It's all about the money you want to spend and don't count gettin' any money back in return upon trade or sale!

With what I have when you twist the throttle...hold on!! And all this is on a heavy '15 Ultra. I've blown away Harley CVO's with 114 inches!
 
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Resist Tyranny
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Discussion Starter #15
I hear what you're saying. The take out cams will be paper weights at best. I'm not looking for a vast improvement but i do think I can gain enough to break into the 13s. The work Jimmers is talking about sounds like the the $3K to $5K range. Since I have already replaced the lifters, chain, tensioners, bearings and pushrods, I think I can do the work myself for under $300. If I can gain .3 in the 1/4 and move my power band up in the RPM range I think it's worth it.

later, dozer
 

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You would be better off, having your heads ported and then use a thinner head gasket when you put it back together and then you will see a better difference.
 
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You'll be going backwards with the 585 it needs around 10.5/1 c-r to work. Have the heads done Bigboyz does great work and not as spendy as most and have the tbody cleaned up and retune and you should get what you want. Also you may consider changing your gearing remember it not how fast you go but how quick you get there
 

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Resist Tyranny
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Discussion Starter #18
After further study, I will agree that the 585 would be too much. I don't think having the heads done will produce the desired result with the 37H. I can accomplish a cam change for about 3 C notes and more importantly one day down time. Pulling the heads and sending them off will run well over a grand and at least a month of down time. Besides if I go to the trouble of pulling the heads I may as well do a big bore kit. Either way the head work and/or big bore kit with higher compression won't realize their full potential without upgrading the cam too. So I think the place to begin is to upgrade the cam and then when I have the time and the cash maybe do the heads and jugs.

later, dozer
 

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I hear what you're saying. The take out cams will be paper weights at best. I'm not looking for a vast improvement but i do think I can gain enough to break into the 13s. The work Jimmers is talking about sounds like the the $3K to $5K range. Since I have already replaced the lifters, chain, tensioners, bearings and pushrods, I think I can do the work myself for under $300. If I can gain .3 in the 1/4 and move my power band up in the RPM range I think it's worth it.



later, dozer


TW 777. Come on about 2700 rpm, really kick in about 3000 rpm thru redline. My Slim dyno'd at 97hp and 109 ft lb torque.
 
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