exhaust and cam relationship

[Ed S]

Currently running a 06 SG with 95in. SE flat tops, 203 cams, 190 main jet, stock needle raised with a washer, rinehart TD, stock heads, stock HG, and stock ign. Am not really happy with the power band of the cams, and it pings real bad. Had the work done by a bud who works at the local dealer, full of the MoCo propaganda. He never claimed to be an engine builder, and I foolishly assumed that if I went with Harley stuff it would work. I can't leave it pinging like it is, and I'm afraid that just backing the timing down with a DTT module will negate the performance gain. I can come up with enough coin to change cams and head gaskets. I think I'd like to go with the Andrews 21 or 26. My question is if I will get enough squish to help with the detonation if I go to the .030 HG, and how much am I giving up with the Rineharts. I want to spend my limited funds as wisely as possible THIS time. I know there is no absolute answer without knowing deck height and AFR, but the bike doesn't "feel" lean, I just need the best bang for the buck now.

[Sonny S.]

Your AFR is lean
Try a 195 main, NOKK needle, 46 or 48 pilot. If you go 46 you might be 2.5 turns on the mixture screw, 48 1-1.5.
I don't have the # for the needle with me right now.

Many will suggest the N65C needle but I have found it to have a very lean transition to the main and will actually cause a roll on ping especially on a heavy bike. Also milage will suffer

I was running a 48 pilot, NOKK, 205 main in my 01 Ultra, 95", TW37's @9.5, 06 heads cleaned up by me, SuperTrapp 2-1.
and I was getting 40+mpg highway. I tuned AFR using a WEGO III.

[fxstbob]

What Sonny said.
It's much cheaper to get what you have running right than changing cams, in which case it would still need tuned to see any improvement. That's probably why you say you don't care for the powerband, it's simply not running right. Tune it and you'll be happy.

[Admiral Akbar]

"and stock ign. "

I remember when I was in high school, we always thought that advancing the timing made more HP. Well when you increase the compression you need to retard it.. The fire in the cylinders burns faster.. Jetting is probably off but I'd install a DTT.. Dial setting will more than likely get you where you want and you will pick up power..  Max

[Trouble]

You could try getting the '88 sportster needle for the carb, and I would suggest the SE ignition module that retards timing 5* while under load. You don't have anything radical in there that would suggest something more aggressive, just match the mild build with these mild tuning mods. The retard from the module disappears once the manifold vacuum builds and I have always enjoyed 42-47MPG with an identical setup to yours.

[harleywood]

What is this NOKK needle you speak of?   

[Fxstchewy]

Where's it "pinging at? low rpm roll-on or high rpm pass?

[harleywood]

I have the same issue further exasperated by the addition of the SE Hi compression pistons. I have remapped the SE ignition module with a 12deg retard map and still have ping both at low RPM roll-on and WOT. ( I did not put this combo together...just trying to sort it out)

[Don D]

If the mechanical compression ratio is above 9.5/1 corrected for camshaft you are likely to have detonation issues which will be made worse by poor squish and or domes pistons.
The NOKK needle is PT # 27241-95
I have had good luck with a DTT ign and dials and ocassionally a custom map.
Prerequisite is reasonable mechanical compression ratio.

[GoFast.....]

The exhaust is the last thing you need to worry about

[ClassicRider2002]

Am not really happy with the power band of the cams

Ed S....

MERRY CHRISTMAS TO ALL!  

Well, the guys above will get you all figured out with your needles and jets....for better running.....but I am still caught by what you said above that you aren't "real happy with the power band of the cams you are running.  I must admit I know very little about your cam's characteristics because I am not running your cam.....I also don't know what your weight is, how often you ride two up, what the weight of your passenger would be, what type of riding you enjoy, are you at sea level or in the mountains, do you ride in the mountains or do you chase a straight line from state line to state line.....our enviornments play a great role or I should say they should play a great role in our cam selections but often times are over looked......Are you the type of rider that can honestly say that you NEVER take your throttle above 4,500 RPM's or do you like to wack it to red line all the time......most of our riding typically is spent between 2500 RPM's to 3500 RPMS.....so if this is the case for you.....I am thinkin no matter what you do with your "tuning" you potentially have the "wrong" cam....but that's ok just chalk it up to R&D......

With your 06 Street Glide, you have what many consider to be the best OEM STOCK Heads for the twin cam to date, so they supposedly flow nicely.....I don't own them so I don't know others would be able to confirm or deny what I am saying with perhaps more accuracy but you are running them as OEM stock heads.....

I am reading some good stuff about the Andrews 21 with the intake closing at 30 which is 6 degrees lower than your 203....which will shift your power band quit a bit about probably 200 rpms.  The 26's would be quite similar I believe to what the 203's are....in that the 203's intake close is at 36 while the 26's are at 35.  The 37's in my opinion wouldn't be the right way to go with your build either as they move further to the right with the RPM band given that they have an intake close of 38.

I am going to send you to this "LINK" below.....take your time....read through it.....send some messages to Bagger he is an interesting person and has some ideas and has done tones of R&D with his bike, he might be able to lead you in a direction, right after Christmas will be an excellent time to catch up on some reading....and others are typically free to help and can guide you.....anyway.....if I were a betting man.....I would say you are into the wrong cam.....only because of what you said above.......but you really have to sit down and honestly access what's your riding style.....once you determine this then it's much easier for others to offer opinions....and when other's are offering their opinions I think it's equally important to understand the same things about them to see if they match up with you....ie: weight, passenger weight, riding style, riding enviornment....etc.....

Here is the "LINK" I mentioned above, SIMPLY CLICK, VIEW, & READ:

95 CONVERSION BY JOE MINTON   AMERICAN IRON

Regards,

"Classic"

[Sonny S.]

I didn't mention ignition because the CCP figures out to be about 172, and that was going .045 gskt & 85cc heads.

Even if your CCP is higher you really need to make sure AFR is correct before you adjust timing. If you remove timing to eliminate detonation, and the real cause was a lean AFR, then you will really be unhappy with the build.
IMHO the last thing you need ignition wise is a -5 SE module. All that's going to do is kill the top end.
I like the DTT's a lot and have two of them. My 01 Ultra I mentioned is running one with a custom map.
Regarless of where you go with this make sure AFR is correct 1st, then timing 2nd.

thanks for the NOKK # Don 
Get one, rejet, and try it.
Pay for dyno time if you must but get your AFR right.

[Faast Ed]

Try running a slightly colder plug along with your other changes.

[Don D]

That is good info on the NOKK, there is another NOKV IIRC too that is a good one to have when playing trying to get the AFR right and not waste fuel.

[Don D]

Here is a list with dimension of all the popular needles

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[03rdkng]

Ed
The power band statement caught my attention as well.
I can not run cams like 203s they just do not match my riding style.
Before you go much further than correcting AFR I would take some time to define what it is your after in performance.
I am probably an exception rather than the rule, I prefer top end over low end torque.
The guys here can minimize your pain.

[Ed S]

Thanks for all the input. I have been an auto mech. for 30 years and I guess I'm comparing the feel of a lean old Q-Jet to what I feel on the bike. It does not feel lean at cruise, doesn't pick up anything when I roll out of the throttle slightly. It pings at all altitudes and temps., from 600' in St. Louis to 4000' on the BRP at 50 deg. to 3000' at 105 deg. in Utah.It doesn't just rattle a little as I'm rolling on the throttle, it will rattle the piston out if I leave it loaded hard. The cam has always come in a little later than I want and was expecting, it runs much better than stock, just want the torque sooner. I'm getting 40-45 MPG at 70-75 MPH, two up, loaded. Definitely going to go with the NOKK needle and maybe a 195 main, question is, is there enough benefit to the .030 head gaskets to be worth the labor, or should I forget about it? The cam change is not a have to, unless it will help the ping, was just considering it. I keep reading about squish and cams and just wondering how much help these areas would be, would I even need to buy a module? 36,000 miles and never been on the rev limiter, just want it to pull real hard from 2000 to 4500 rpm. Any faster and the OL starts swinging.

[Trouble]

Beware! I brought my cams and cam plate to a dealer for installation and got them back one tooth off. So, there may be more than one reason your set-up won't run right. This shouldn't happen; you have an easy modification and need'nt get more complicated. Do you have an excessive amount of carbon on your pistons?

[mayor]

check your cold cranking pressure to see if your inline with what the build and your elevation calculates.  As Trouble mentioned, maybe you have other problems.  I ran stock heads using .030" head gaskets and flat tops with the 203's in a 95" - and never had a ping issue, even at sea level (although it was in a lighter bike  ).  Check ccp, then as Sonny mentioned check your AFR.  You're probably lean.   

define "Am not really happy with the power band of the cams"- runs out of steam too early or doesn't rip your arms out of sockets from idle?

[Ed S]

Doesn't start coming on till 3000. Was told it was going to have more low end. It's real impressive from 3000 up, maybe cause its lean. Too much I don't know. I'll check ccp and change needle and jets. Wish I'd found this forum when it was warm.    Trouble- what symtoms did you have? Carbon not an issue, been doing it from day 1 of build, 17000 mi. Still wondering if thick HG are a problem.

[mayor]

check your cold cranking pressure to see if your inline with what the build and your elevation calculates.  As Trouble mentioned, maybe you have other problems.  I ran stock heads using .030" head gaskets and flat tops with the 203's in a 95" - and never had a ping issue, even at sea level (although it was in a lighter bike  ).  Check ccp, then as Sonny mentioned check your AFR.  You're probably lean.   

...oops, also forgot to mention that I was running a 5degree retard SE ingnition too (which will make a difference in relation to ping).   

Doesn't start coming on till 3000. Was told it was going to have more low end. It's real impressive from 3000 up, maybe cause its lean. Too much I don't know. I'll check ccp and change needle and jets. Wish I'd found this forum when it was warm.    Trouble- what symtoms did you have? Carbon not an issue, been doing it from day 1 of build, 17000 mi. Still wondering if thick HG are a problem.

...part of your below 3k experience could go back to your original question- exhaust and cam relationship. Maybe some guys with experience with Rinehart True Duals can weigh in on that ...it could also be cam specs.  You can move the torque up earlier as you mentioned by switching to a shorter duration, earlier intake close cam like Crane HTC-300 or the Andrews 26 or 21 that you mentioned. 

You can also bring the torque on a little earlier by increasing the static compression.  Assuming that a stock head gasket thickness was used (.052"), switching to a .030" cometic will bring your compression up .38:1 compression and if the head gasket used were .045", the compression would go up .26:1 by switching to the .030" hg's.   

[Bakon]

203 cam closes at 36, which is a relatively low pwer range cam. Its the Rhineharts which hurt you down low. I love them, but they have a low end torque dip just before 3k rpm.

Your cam should be 2500-2700 to come on.
A 38 intake is about 2800-3000.

But the TD pipes have a dip.

Quench or squish will help everywhere when set right. The cam close/ compression ratio is the other part for low end. You would be better with stock head pipes for low end.

Start looking a dyno charts with Rhineharts- you will see a smaller rise or a drop right before 3k, but a pick up in rise after that.

[Don D]

OK something is smelling a little funny
Pinging with under 9/1 corrected? Dead out of the hole with 203 cams?

Considering everything IMO
The pipes are culling a little not a lot down low if they are the 2" and not the huge baffles
The new stock composite HG are .040 I think just for figures, dealer techs can confirm
The SE ign module and retard is not needed and could be causing issues
Ping is likely caused by excessive squish and lean condition

Try the original module just for the heck of it.
Take a compression test and report back
Cams have been known to be defective or installed wrong and the compression test could lend creedance to this.
Tell us the baffle size

[Ed S]

Gonna ck compression Fri. Don't know deck height, just original cyls. with SE pistons. Can't imagine too much compression or squish. Was just supposed to be a little more power without losing any reliability, lots of miles yearly. Actually would be ok if not for ping. If I have to take it apart to fix that, I might as well try to make it do what I really want. The snowball just keeps getting bigger.

[Bakon]

Out of the box my SE parts were mid 40's on the squish. As bad as 50 in spots (95 htcc pistons have multiple areas). When tightened lost alot of the low end dip, but still can be seen on a dyno. But this is a cam change too- S&S585 to Woods 400g, lots more lift and intake close from 46 to 42.

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