FN Cheap Cam install

[dolt]

You will find that most cam manufacturers always understate compression rating for their cams; CYA stuff. You will have to trust me on this in spite of what Andrews or other cam manufacturers advertise. You will notice some improvement if you install the 57 cams but it takes static CR of 10.2 to bring those cams to life. If you take the time to go on line and use the BigBoyz compression calculator to compare cams, you will see for yourself which cams would be best suited for you application. Personally, I say stick with the SE255s with an otherwise stock or Stage I configuration.

A good target for a street build would be to set CCP between 190-195psi and/or corrected compression between 9.3 and 9.5. If you set up the calculator at 9.6 static, you will se that the 57 cams produce corrected compression at 8.97 and CCP at 184.5psi compared to the SE255 which produce corrected CR at 9.36 and CCP at 194.7psi; perfect for a street build. The Andrews 48 numbers are 9.26 and 192psi; all numbers are at sea level so would have to be adjusted for your altitude but you get the picture.

Of the Woods cams, the 222 is the only one worth a look but it isn't much better than the 57 at 9.1 and 188psi.

http://www.bigboyzheadporting.com/TwinCamComp.htm

Just providing some real world data for your consideration; your ride, you decide.

 

[CHZWIZ]

You will find that most cam manufacturers always understate compression rating for their cams; CYA stuff. You will have to trust me on this in spite of what Andrews or other cam manufacturers advertise. You will notice some improvement if you install the 57 cams but it takes static CR of 10.2 to bring those cams to life. If you take the time to go on line and use the BigBoyz compression calculator to compare cams, you will see for yourself which cams would be best suited for you application. Personally, I say stick with the SE255s with an otherwise stock or Stage I configuration.

A good target for a street build would be to set CCP between 190-195psi and/or corrected compression between 9.3 and 9.5. If you set up the calculator at 9.6 static, you will se that the 57 cams produce corrected compression at 8.97 and CCP at 184.5psi compared to the SE255 which produce corrected CR at 9.36 and CCP at 194.7psi; perfect for a street build. The Andrews 48 numbers are 9.26 and 192psi; all numbers are at sea level so would have to be adjusted for your altitude but you get the picture.

Of the Woods cams, the 222 is the only one worth a look but it isn't much better than the 57 at 9.1 and 188psi.

http://www.bigboyzheadporting.com/TwinCamComp.htm

Just providing some real world data for your consideration; your ride, you decide.

Just got home and checking out the calculator. Thanks for the link Dolt.

SE 255 - 9.58 cc / 200.7 ccc
Wood 222 - 9.33:1 cc / 193.8 ccc
Andrews 57H - 9.19:1 cc / 190.1 ccc
Andrews 48 - 9.48:1 cc / 197.9 ccc
Red Shift 525 - 9.73:1 cc / 204.6

103CI 3.875 X 4.375
head gasket .045
head gasket bore 3.910
cyl head vol 85 cc
piston dome vol 1.3 (average between the two figures)
static compression 9.89:1

So according to your calculations the Wood 222 or Andrews 48 would be the best match.

 

[CHZWIZ]

Just put the SE 204 in the calculator
9.33:1 cc / 193.8 ccc @ SL

 

[CHZWIZ]

So it looks like the S&S 557 might work also.

 

[dolt]

So it looks like the S&S 557 might work also.

Looks like you need to re-run the numbers, set deck height at .007" as 103" pistons are usually down in the hole .007"-.010" and use 86cc as chamber volume. Specs for the FLHTP 103" motor set static CR at 9.6 but you are using 9.89 which throws everything off. Also adjust for sea level if you are at a higher elevation. Why not run a compression test on your bike and get a baseline CCP?

If you want torque, the SE255 is your huckleberry up to 4000rpms; JMHO but the 48 would be a better choice as it will carry out to about 4500 and will make more HP.

The SE204 is actually a great cam for a 103" motor but will perform better with the addition of the 1.7 ratio rocker arms to increase the lift. The 204 will give away a little to the 255 and 48 on the lower end but a strong mid range cam and will carry out to the rev limiter but better suited for a dyna or softail; the FLHTP is a heavier bike.

Lot's of choices, just need to decide which best fits your riding style.

 

[CHZWIZ]

So Dolt I reentered the figures into the calculator. Hopefully I did it correctly. So now that I recalculated the figures I dumped a few of the cams. This is all the choices in the calculator that falls into the spec range you posted. I live on sea level in Washington State and the highest elevation I would ever ride at in the state is 5500 ft.

I know from reading prior posts that your not to hot on S&S EZ start cams but I don't think they would be a bad choice. I like the idea that they don't stress the starter and battery. I know I have the ACR's but those could be turned off or removed and plugged.

The 583 cam seems like it would be really good making power from 1500 - 5000. Not sure if the lift is to much for stock springs. They list it as a Dyna cam but have read lots of Touring owner have installed them and really love them. About $350

The 557 is a Tri Glide cam and looks like it will pull stumps. I read a post that it pulls up to 6k. Not sure if this would be a better cam than the SE 255 or not. I see no reason it couldn't be used in a touring model.

The 551 power from idle to 4000.

Can't find a lot of info on the Red Shift 525 but looks to be decent. Any comments on this set?

The 48 would be my best buy. I can get a new set on Amazon for $212. Probably would be the best choice. All the vids I've seen with the 48 the bikes sound great. Andrews says it makes good low to mid power. And you say up to 4500.

Have been looking at used SE 255 cams on eBay but find them going for about the same price as a new 48.

Definitely need a cam that can work well with elevation changes, lots of hills in the NW.

Also Dolt, how do you decipher the BB cam comparator.

103CI 3.875 X 4.375
head gasket .045
head gasket bore 3.910
cyl head vol 86.6 cc
piston dome vol 1.5
deck height F&R .007
static compression 9.6:1


MAKE CC CCC
Andrews 48 - 9.48:1 / 197.9
Red Shift 525 - 9.45:1 / 197.1
SE 255 - 9.31:1 / 193.4
S&S 551 - 9.43:1 / 192.1
S&S 557 - 9.26:1 / 192.1
S&S 583 - 9.45:1 / 197.1

 

[dolt]

The 48 would be my best buy. I can get a new set on Amazon for $212. Probably would be the best choice. All the vids I've seen with the 48 the bikes sound great. Andrews says it makes good low to mid power. And you say up to 4500.

Have been looking at used SE 255 cams on eBay but find them going for about the same price as a new 48.

Definitely need a cam that can work well with elevation changes, lots of hills in the NW.

I really don't t have an issue with the EZ start cams. Lots of them running with no issues but there is a moving part involved and given the choice between EZ start cams and compression releases, I will go for the compression releases. Suggest you take whatever steps necessary to make sure your ACRs are operating properly.

The post '05 beehive springs will accommodate lifts up to .600" but I would check for coil bind with a .600" lift cam because factory tolerances do vary.

I think you will be happy with the 48 and believe it is the best choice of the cams you listed.