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Discussion Starter · #1 ·
I am planning on the Harley 95" Stage II (to stay in warranty) and from their dyno charts and even dyno charts posted in this forum, if your goal (like me) is good low end torque I don't see the significant benefit to head mods or new heads.

Better flowing heads look to mostly give excellent HP increases, but well up in the RPM range, and makes all of the sense in the world for a drag racer or someone who just wants to have a certain number.

I would think the somewhat restrictive stock heads help maintain good torque in the low to mid rpm range. Sort of like drag pipes with no baffles, where top end HP is the real goal.

I can appreciate people like Deweys, etc. who make a big contribution to the sport.

Any opinion if my keeping stock heads thoughts is way off base? :corn:
 

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XLIII
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Actually, good port velocity is what gets you torque. Hogging them out is for HP,to put it way too simply. Good head porters balance the 2.
 

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Discussion Starter · #3 ·
MegaGlide said:
Actually, good port velocity is what gets you torque. Hogging them out is for HP,to put it way too simply. Good head porters balance the 2.
True. That is what I meant to indicate, that a small amount of restriction should maintain air velocity, like in an exhaust system, and that hogging them out willl hurt low end but give big top end HP numbers.

Yes, good head porters balance the 2, I just meant for my intended use, low end grunt & cruising, the stock heads would probably do the job. The cost of a good head job (did I say that?) may not be worth it to many of us.

Somebody slap me for that last line.......+SMSH+
 

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I wound up with a build from hell....

See my sig below.

I'm going back to 203 cams and stock heads over the winter. Harley's got a nice canned map for that one, and noone up here seems to know how to tune EFI bikes all that well. That 2-3000 rpm torque curve looks awfully good to me too.

I was planning an Axtell 107", but for what that would cost, I could buy half a V-Rod, which would probably be a whole lot more fun.
 

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Discussion Starter · #5 ·
EricEdelman said:
See my sig below.

I'm going back to 203 cams and stock heads over the winter. Harley's got a nice canned map for that one, and noone up here seems to know how to tune EFI bikes all that well. That 2-3000 rpm torque curve looks awfully good to me too.

I was planning an Axtell 107", but for what that would cost, I could buy half a V-Rod, which would probably be a whole lot more fun.
I am no expert, but I just thought the Harley Dyno chart in the Screamin Eagle catalog for the 95" Stage II covered nearly all of the numbers of the expensive big upgrades, looked like a good deal that would work in the everyday world for an EFI bike. I think this will satisfy my needs.

Good luck with your plans. Either way you got a killer Harley, life is good. :beer4u:
 

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EricEdelman said:
See my sig below.

I'm going back to 203 cams and stock heads over the winter. Harley's got a nice canned map for that one, and noone up here seems to know how to tune EFI bikes all that well. That 2-3000 rpm torque curve looks awfully good to me too.

I was planning an Axtell 107", but for what that would cost, I could buy half a V-Rod, which would probably be a whole lot more fun.
Just my humble opinion but I think a good tuner ought to be able to make
your combo work. Good Race Tuner guys are few and far between.
 

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XLIII
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EricEdelman said:
See my sig below.

I'm going back to 203 cams and stock heads over the winter. Harley's got a nice canned map for that one, and noone up here seems to know how to tune EFI bikes all that well. That 2-3000 rpm torque curve looks awfully good to me too.

I was planning an Axtell 107", but for what that would cost, I could buy half a V-Rod, which would probably be a whole lot more fun.
Eric, just put in Andrews 37G cams. I've got 95 Ft/Lb of torque w/ them, smooth as silk, NO detonation even w/ the 2 degree advance key, and I'm using the same heads as you. If you weren't using a 2:1 pipe, I'd send you my map...
It ain't the heads. While a porter can do better, I've got over 80 ft/lb at 1900 RPM...
It ain't rocket surgery. Somebody here can send you a map that will work. It might not be optimum, since it wasn't tuned to your bike, but it'll beat the 203s...
 

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Thanks for all the suggestions....

I know about the 37g cams, and how much of a crowd favorite they are here. But bottom line for me, is that I'm not dragging the bike all over the country to get work done (I'm 3 hours from Potsdam.).

I'll probably buy a second bike in a year or two, and either do a Jim's 120 or an S&S or Zippers motor. Hopefully by then Harley will have closed loop injection on all the bikes and the aftermarket will have goodies that work with it.

On the other hand, our local dealer just got the new Dynojet 250i dyno, so it's possible one of his techs may figure out how to use it one of these years. :)
 

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XLIII
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How far are you from CT?
GRock is there, and I don't think you can do better than him for a FI guy...
 

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I've got S&S 510 G cams and stock heads in a 95".Works great and kicks ass until 4800 rpm when the torque curve drops. Horsepower seems unaffected,I'll be doing heads soon.
 

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Eric, ditch the 211's and go with S&S .570 cams. You have all the right parts to go with these cams. Using the SERT and a good tuner (See thread "Top Tuners") should get you 95hp/100tq with no detonation. Very reliable and fun. Hippo's done many of these.
 

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Big fat holes with ginormous valves are for racers. Big holes and valves aren't necessarily bad so long as they're the right shape, too. However, the bigger the holes the lower your port velocity, all things being equal. A well done valve job with a conservative massaging of the port-seat transition and bowl area is fine for most applications, I think (I recommend better valves while you are at it, and guides depending on mileage). The more radical you get with displacement, revs, and cam, the further up the port your porting job needs to go. For most of us the first 1" of port under the seat is what matters.

My heads have big holes and valves but the flow numbers are HUGE. So the velocity must still be there. Big holes with kind of big flow numbers probably won't work well down low. My heads are probably a little too agressive for my cam (wood W6H), but maybe I'll change the cam next year. More duration and wider LSA won't help my bottom end, but as it is I have heads that will flow big air and a cam that won't feed it much air. It's not as bad a match as I make it sound (if you TC guys want to race my Evo you better bring more than 95 inches). A friend's stock 1100 Guzzi will pull me in 5th at 60 mph (he'll get a length or two in front of me), but once my revs hit about 3K, maybe 3.2K, that sumbitch comes alive. After that it's a sorry sight. When I hit 120mph he was a very small piece of scenery in my mirror. Of course, I would never do a 5th gear roll-on. I'd jam 4th and he'd put his kickstand down at 60mph to investigate why he's standing still.

Chilly
 
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