2 years ago I had my 97 wide glide 80 inch engine rebuilt with a 4 5/8 stroker crank, bored .20 over Ross ceramic coated pistons, ported polished heads, bigger valves, shaved heads, 11:1 compression..etc.Im running a worked super E carb,and crane ignition. Its about 94 cubic inches now.The builder installed an S&S 520 cam.My question is..shouldnt I be running a bigger cam? Im thinking the S&S 585. Dont get me wrong this thing rips, but Ive seen similiar setups running alot bigger cams. Any thoughts?......Thanks

 

andrews S84,brutal cam,done a couple hi compresion shovels,make damn good power

 

Bigger aint always better.

 

How do you figure 94 inches? A 4 5/8" stroke with a standard evo bore is 89 inches. The extra .020 doesnt really add that much. You need to know how much the lift valves are clearanced for before you start swapping cams. A 585 cam has lots more lift. How does it start with the 520 cam? S&S shows it for up to 10:1 pistons.

 

You can overcam a engine,if it runs great,and ur happy with,trust youre builder and leave it alone.

 

Are you happy with the way it runs? Do you experience pinging or detonation? IMO, yes, that engine is undercammed. If you said 9.5:1 or less CR, then I would say the 520 would be fine, maybe it is in your application, but with that much compression (is it really 11:1? That's a lot for an air cooled V-twin) I would definately want more cam to bleed off cylinder pressure.

With ported heads, the extra cubes, and that much compression, I would throw quite a bit more cam at it, it takes a lot of cam to run 11:1 on 91 or even 93 octane in an Evo, and you've really got to stay on top of your carb tuning or you'll be melting holes in pistons, or rattling the bottom end apart.

Do you ride solo mostly? Bar hopping/ Hot Rodding? Cross country? How often are you willing to check/ change valvesprings, or replace Valvetrain components? High duration/ High lift cams with fast ramps are going to wear out faster/ be noiser than milder ones. Lots of choices for cams, Any of the Woods W9 series cams would wake it up. That 585 would work, too. You are definately going to have to check piston and valve train clearance with any cam change.

FWIW, a friend of mine built a really nasty 88 inch S&S a few years back, 11:1, heavily ported, with an S&S 631 cam. Bike had plenty of bottom end for a light bike, even 2-up, but pulled progressively harder with RPM, moreso than any other bike I've ridden. Was it overcammed? Yeah, for 99% of the people out there it probably was, but for that bike and owner it worked well. The bike didn't run that hard unless you had it wide open and on the cam, but wide open and on the cam it was unbelievable. When it was spooled up, it was just as fast as any 107, 113, etc., that I've been on.

I enjoy arm stretching bikes that pull hard to 6000+ RPM. I run an Andrews EV-51 in my 10.5:1 80 incher FXD. It pulls like a freight train on the upper end, but still has plenty of bottom end with the increased compression. That being said, I am in the minority, and for most people and builds torque is king. I also do my own maintenance, so the extra time spent wrenching is not an issue for me.

All of that being said, theories and paper aside, if it runs well, and you are happy with it, I'd leave it alone.

 

if your compresion will support a longer duration,big cam,and you know what your doing setting it up,nothing better than a big cam in a hotrod or drag motor

 

I do ride the bike hard at times, you know how it goes when you get a bunch of gearheads together on bikes, lol. Anyways,the springs that the builder put in are supposed to be good up to a .700 lift. He built this thing to run, D ported heads, etc. Thats why I dont quite understand the .520. It will out run a buddys 96" s&s consistently but Im just wondering if a more agressive cam will "wake" it up even more. The compression is actually at something like 10.8:1 it is definitly high, im on my second starter. The bike runs great as is, but you know how it goes always trying to squeeze a little more out of it. I may try a woods 8 here in the next week or so and see what happens.Its just a cam change, if it ends up affecting the performance I can always switch back. I was just looking for suggestions to experiment with.

 

Same thing ive got in my dresser.Tq is 84ftlb at 2600 and stays there till redline(6000)
Hp is the same 84hp straght to redline.It feels awesome for an evo dress.

 

Frankly, with that much compression and cubes, that W8 is still too small, IMO. If you are going to purchase the cam, I'd go at least one step bigger. If it's free, throw it in and see what happens. Duration is what is going to lower your cranking pressure, and build power.

Just for reference, your 520 has 220/232 duration.
Woods 8 has 246/246, around the same as an EV-46, but with more lift. Guys are running the EV-46 cam in stock 8.5:1 engines with good results.
EV-51 has 252/256 duration. This is what Legacy and I run in our modded 80's. If I had ported heads, or more cubes, I would want more cam.
Woods 9 has 252/252, for the most part, with varying lifts depending on model.
The more lift for a given duration, the more power, at the expense of valvetrain life and noise. A heavily built, high compression V-twin is going to need more attention than a stocker, so this isn't really a big issue in my eyes.

With that setup, if the heads are as worked as you say they are, that thing is going to come alive with more cam. Way over 100HP if you give it enough cam. Those cubes, compression, and head porting are going to take a lot of cam and still run great. It's the 8.5:1 stock engines that run like *** with larger cams.

Regardless of how much lift your Valvesprings are capable of, you are still going to have to check valve to piston clearance if you are adding a bunch of lift and duration.

If I was picking a cam for your application, I would throw in a W9B or F, or possibly even the W62 or S&S 640. Couldn't go wrong with an EV-72, either. Well, lets be honest here, I would probably go straight for the W62, W68, or W72 for my personal bike, but I'm pretty screwed up in the head, and ride pretty hard.

If you haven't already, check out woodscarbs.com, and read through http://www.nightrider.com/biketech/ then check out the Evo dyno charts, to get a feel for what you can expect with various setups, etc.