Big bore or cams???
#11
08-13-2010, 06:39 AM
Extreme HDF Member
Sorry my bad, I get stuck on what I have sometimes.
The only chart the book shows for an 88 is with the 95 kit with 203 cams and it is quite an impressive upgrade.
I don't know a thing about the 88 so I'll shut up.
The only chart the book shows for an 88 is with the 95 kit with 203 cams and it is quite an impressive upgrade.
I don't know a thing about the 88 so I'll shut up.
#12
08-13-2010, 06:47 AM
#13
08-13-2010, 06:52 AM
Tourer
Join Date: Dec 2007
Location: On the road to nowhere, UK
Posts: 426
Likes: 0
Received 0 Likes
on
0 Posts
Now here's a question, then..
I have a stock FLHTK Ultra Ltd, which is of course 103ci. In the best value performance stakes, what order does the team think I should take with the 103 to get more performance?
I'm guessing from the posts above, I'd be best in this order:-
a - SE Cams, then
b - de-restrict intake side with free flow air filter, with exhaust side comprising of freer breathing slip-on's (my choice on noise alone would be SE stuff), plus remapping of ECU, then
c - replacement heads to match.
Would this be about right?
What ball park output figures would go with all this?
Hmmmm...
I have a stock FLHTK Ultra Ltd, which is of course 103ci. In the best value performance stakes, what order does the team think I should take with the 103 to get more performance?
I'm guessing from the posts above, I'd be best in this order:-
a - SE Cams, then
b - de-restrict intake side with free flow air filter, with exhaust side comprising of freer breathing slip-on's (my choice on noise alone would be SE stuff), plus remapping of ECU, then
c - replacement heads to match.
Would this be about right?
What ball park output figures would go with all this?
Hmmmm...
#15
08-13-2010, 07:31 AM
Intermediate
Join Date: Feb 2010
Location: Cleveland, Ohio
Posts: 28
Likes: 0
Received 0 Likes
on
0 Posts
Ball park numbers
Now here's a question, then..
I have a stock FLHTK Ultra Ltd, which is of course 103ci. In the best value performance stakes, what order does the team think I should take with the 103 to get more performance?
I'm guessing from the posts above, I'd be best in this order:-
a - SE Cams, then
b - de-restrict intake side with free flow air filter, with exhaust side comprising of freer breathing slip-on's (my choice on noise alone would be SE stuff), plus remapping of ECU, then
c - replacement heads to match.
Would this be about right?
What ball park output figures would go with all this?
Hmmmm...
I have a stock FLHTK Ultra Ltd, which is of course 103ci. In the best value performance stakes, what order does the team think I should take with the 103 to get more performance?
I'm guessing from the posts above, I'd be best in this order:-
a - SE Cams, then
b - de-restrict intake side with free flow air filter, with exhaust side comprising of freer breathing slip-on's (my choice on noise alone would be SE stuff), plus remapping of ECU, then
c - replacement heads to match.
Would this be about right?
What ball park output figures would go with all this?
Hmmmm...
#16
08-13-2010, 07:46 AM
Road Captain
#17
08-13-2010, 08:26 AM
#18
08-13-2010, 09:00 AM
Road Master
The reason that cams are such a big boost is that the stock cams completely strangle the motor in the name of emissions. If you look at the specs for the stock cams in the 96 motors, the intake valve opens 8* after the exhaust valve closes. That's so no unburned fuel can escape along with the spent gasses. Good for emissions, lousy for power production. A performance cam will have some overlap built in. This allows the exiting gasses to help pull in the incoming fuel/air mix in a siphon effect. A little bit of overlap, as well as a little more duration can do wonders for a stock motor, even if there's no other changes made.
Having said that, I'm a huge fan of increasing displacement whenever possible. An increase in displacement will increase torque across the board in roughly direct proportion to the size of the displacement increase. So, a displacement increase of 10% will return an increase of torque of roughly 10%. With HD motors, the big bore kits involve changing jugs and pistons, but leaving the heads alone. This increases swept volume, as you're now pushing more air into the same size combustion chamber. The net effect of that is an increase in compression of about a half point. Increases in displacement and in compression will both lead to a performance boost.
IMO, the biggest reason there's little perceived difference between a stock 96 and a stock 103 is because they use the same stock cams, which very effectively strangle the motors. Once you start adding performance parts, especially cams, the difference in the motors becomes more apparant.
Having said that, I'm a huge fan of increasing displacement whenever possible. An increase in displacement will increase torque across the board in roughly direct proportion to the size of the displacement increase. So, a displacement increase of 10% will return an increase of torque of roughly 10%. With HD motors, the big bore kits involve changing jugs and pistons, but leaving the heads alone. This increases swept volume, as you're now pushing more air into the same size combustion chamber. The net effect of that is an increase in compression of about a half point. Increases in displacement and in compression will both lead to a performance boost.
IMO, the biggest reason there's little perceived difference between a stock 96 and a stock 103 is because they use the same stock cams, which very effectively strangle the motors. Once you start adding performance parts, especially cams, the difference in the motors becomes more apparant.
#19
08-13-2010, 09:04 AM
Boog dude nailed it. Cams first, then displacement. NO engine works to it's capacity until it flows enough air and fuel.
I did the cams first, and the cam plate upgrade to get rid of the crap spring tensioners. I found a great deal on a SE big bore kit that had silver cylinders. A simple paint job fixed that right up, and I now have a properly fed engine and more displacement and am VERRRRY pleased with it. No idea the hp/torque numbers, but my butt dyno is happy every ride I take.
Do the cams straight away and big bore if funds permit.
I did the cams first, and the cam plate upgrade to get rid of the crap spring tensioners. I found a great deal on a SE big bore kit that had silver cylinders. A simple paint job fixed that right up, and I now have a properly fed engine and more displacement and am VERRRRY pleased with it. No idea the hp/torque numbers, but my butt dyno is happy every ride I take.
Do the cams straight away and big bore if funds permit.
#20
08-13-2010, 09:21 AM
Perhaps I need to clarify, I did the big bore concurrent with the cams....found the BB kit while I had the bike down for the cams. So, I don't have an incremental power improvement report for you. I went from stock 88" with opened up mufflers, Ness breather, and PC III, to cams, BB and modified PC III program for the new upgrades.