Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
It'll be close. Depend on the exhaust really. I'm not saying they're bad by any means. I just prefer them to rev a little higher and the 3.5° takes it the other way 200-300rpm. They'd be similar to the S&S 570s I run too without that 3.5°. They're done at 5700.
Be interesting to see how they do and what your tune looks like. The moco has a dip in timing somewhere around 3000rpm WOT for their stage 2 w/ 204s base cal in the SE Pro Super Tuner software. They have a 4° advance grind as I recall.
Originally Posted by PureHybrid
Sure about that? Unless the S&S site is wrong, the lobe centerline is 100/107 for the 570's. Which doesn't bother me, if I ran one of their cams it would be that one, IMO it probably runs out the top better due to increased duration. The 570 is riding that fine line of needing a .030 HG swap.
It is a fine line. I got the .030 top end kit before I did the cams and haven't done it because they do pretty well stock but I know it would be a little better. My ccp is 190psi now.
Originally Posted by djl
Pretty sure the 204 cams have 8* ground in advance.
You may be right. I thought 4° but I'm not sure by any means.
Use Comp cams in my shovels, love them. Quieter, not as hard on the valve train in general and great very usable power bands in the RPM range we actually ride in daily.
Use Comp cams in my shovels, love them. Quieter, not as hard on the valve train in general and great very usable power bands in the RPM range we actually ride in daily.
Well you just described the 570s too tho and I got those pretty cheap getting the ones without compression releases built in. I'd have to look at my bill but I seem to remember $290 for the cams. Maybe it was $270. Somewhere around $100 cheaper than the EZ start version. Good power 2200 to 5700 but I quit making power at 5500 with my exhaust and compression. Cams come on at 3000. Mid 90s hp and 105ish torque but 93ftlbs at 2200rpm.. I'm not sure where it's at now with the 30 tooth sprocket from Evolution Industries. I'm not sure what effect it has on actual torque but I would think a fair increase.
Never made it to a dyno to test just the cams, continued to run the map from FM. Got a wild hair up my rear and sent a spare set of heads to Don to get his "street pro cnc" setup. One of the heads had a crack around the intake valve guide area, he luckily had a core. Heads rolled out at just under 265cfm, similar to most guys "stage 2" heads. Target CCP is 200psi
Got everything together last week, had to "modify" the intake valve relief to get more clearance, it was .038" with checker springs. In theory intake side can be pretty tight but I opened up the relief incase I changed cams down the road and they had a lot more TDC lift... FM sent a base map but I'll definitely get it tweaked in on the dyno, sometime.... Busy summer planned ahead.
Went to a local track tonight, Pacemakers in Mount Vernon, 1/8mi. Was there to run the truck but decided to trailer the bike to run both. Went 8.40 first pass, 8.33 second pass. Pretty soft 60ft since I wasn't sure how it would handle on the track, they weren't spraying any prep
Went to a local track tonight, Pacemakers in Mount Vernon, 1/8mi. Was there to run the truck but decided to trailer the bike to run both. Went 8.40 first pass, 8.33 second pass. Pretty soft 60ft since I wasn't sure how it would handle on the track, they weren't spraying any prep
sounds like they are getting it done for you. Any plans to dyno tune it?
sounds like they are getting it done for you. Any plans to dyno tune it?
I intend to yes, but no plans. I need to get ahold of "the guy" in the area. Supposedly he does the tuning for Hale's HD and a couple local shops, and has a dyno at his house
I intend to yes, but no plans. I need to get ahold of "the guy" in the area. Supposedly he does the tuning for Hale's HD and a couple local shops, and has a dyno at his house
09-21-2020, 08:06 PM
