hey guys i have a TC88 with stroker kit, BB kit, S&S pushrods, SE tappets, SE camplate, SE oilpump and unfortunately SE 204 cams.

now i made my homework and i wanted S&S cams but the mechanic at my local harley dealer talked me into getting the SE 204 cams and i regret it, i has a lot of max hp and max torque but not where it actually matters so my question is what cam would get me a straight line from 1500-5000rpm? after 5000rpm it can go down like a rock for all i care i have a rev limitter set to 6000rpm anyway. the main thing is i cruise at around 2500rpm but i sometimes like to twist the throttle and thats when i want my powercurve to go up not down like it does now, also i was wondering, i have the SE cam bearings so if i switch to lets say wood 777's can i just leave the SE bearings in?

well let your idea's loose upon me

 

777 would work as long as you have at/near 10.4 cr to optimize the compression for the delivery, and overall power of that cam.
Scott

 

if your 9.6-1 to 10.0-1,look at the S&S .570`s

 

hmm i guess i need to bring it in to measure compression, thanks guys

 

Scott and Kirby: Can you guys educate the rest of us just a bit on GENERICALLY what types of cams require what levels of actual compression, and how failure to understand that can make a good cam bad for a specific situation?

It's an area I've never needed to understand well before now, but I am gathering, because of the attention you guys put on it when replying to forum questions, that it is more important than normal for Harley engines.

Jim G

 

You want to match the cam to your riding needs, for the cubic inch, spring pack, and compression ratio, for plug and play application.
When doing a build, we like to talk with our clients, and ask a few questions regarding what model, 2 up riding?, how they ride, etc.
At that point we can start to put togather a plan.
Cam lift/dur/timing numbers are only a part of the equation, and always remember, there are no magic cams out there, magic beans maybe, magic cams no.
Scott

 

EFI or carb? If EFI, how was it tuned? That will make a huge difference, so you know. Generally, most folks like 204s, but with a bad tune, there could be more in it if fixed up properly. And, how about having the shop do a ccp test. Or you do it at home, for that matter. Cold Cranking Pressure. Maybe your cams are off a tooth? Maybe the compression is not set up properly for the 204s? A ccp test is a first good starting point, and all the test consists of is running a compression tester in each hole and recording the readings. I like to see between 185 and 195 psi, ccp. If one cylinder is more than a couple points different, it can show if the cams are not timed properly, like one is 185 and the other is 150, for example.

Can you post a dyno sheet?

PS... Hillsides is soooooo correct about getting info from owners. On forums, everyone seems to pick too big of a cam, and then complains about it. This is due to the gotta go bigger syndrome. When someone asks me? And they have two cams in mind? I will always tell them to use the smaller cam to counteract the big is beautiful thing.

 

ive us a idea of your riding style (RPM`s you usually ride in)& what youde like to have power/tq wise

 

I know you were just throwing the tw777 out there but does woods make a conversion cam for the TC88?

 

Ok, let's try this:

Want an engine that likes to rev
Rev limit 6200
Ideally 110 to 115 peak rwhp
Ideally torque peak in 4000 to 4500 range
Ideally 50 rwhp ( 97 ft lb torque) by 2700 rpm
Ability to steady-state cruise comfortably at 2170 rpm without distress, since stock gearing in 6th = 2170 rpm at 60 mph, but if it helps significantly, I DO plan to change the gearing by 6.7%, so rpm at 60 mph will become 2315.

The engine has automatic compression releases.

The CCP was actually measured recently by a qualified tuner (Mike Lozano), and came in at 210 (actually a tiny bit more on the super small gage - hard to read, maybe as high as 212 or 213) with both cylinders identical within the accuracy capability of the gage.

Current specs:
SE-259E cams
10.5 forged pistons
CNC ported factory heads (1.875" intake valves, 1.575" exhaust valves, heads milled to restore stock combustion chamber volume, valve springs good to 0.585" lift to at least 6200 rpm)
Perfect Fit pushrods
58mm throttle body with "hi-perf" injectors
Hi-perf clutch spring

Current peak power with this setup is only 102 to 104.4 rwhp peak at 6000 rpm and above

Peak torque is only 102 ft lb with >100 from 3800 to 5100, down to only 78 ft lb at 2700 rpm.

Current fuel mileage is "too" good at 43.5 to 45 mpg typical per tank for normal highway cruising (too lean?), and high 30s when having fun in Texas Hill Country (lots of speed changes and topography).

I Always use 92 octane fuel (that's what's standard for premium in our area), and the fuel contains zero to a maximum of 10% ethanol, varying by gas station

The ambient outdoor temperatures in my area range from 32 degree lows in January through 105 degree highs in August, but I only use the bike in 45 degree to 95 degree weather (why suffer? ).

Riding is 95% solo, with rare passenger (wife) for short outings only (ever looked at the passenger seat on a 2014 Breakout?).

The bike is light for a Harley: 2014 Breakout with wet weight about 700 lb. I weigh over 235 lb with all my heavy gear on (safety conscious).

Primary usage is fun outings in Texas Hill Country, with lots of speed changes - down to 30 mph on tight turns then back to 60 to 80 mph, enjoying the acceleration capabilities and higher rpm getting there. Like to hear the engine at 3500 to 5500 rpm. Like to feel high G acceleration.

2 to 5 times per year, plan to do "lightweight simplistic touring": 25 lb bag on sissybar, NO windshield, with trips from 300 to 3500 miles, at "enjoy the scenery pace" (rarely above 70 mph).

Suggestions for a cam?

Jim G