Topic: In a 103" use TW26 or TW37? (Read 9964 times)

BaggerDad · « **on:** February 18, 2006, 01:17:01 PM »

Instead of using a larger cam in the 103", why not use a cam that closes the intake valve as close to 30 deg ABDC to produce more TQ off idle.

BaggerDad · « **Reply #1 on:** February 18, 2006, 01:19:36 PM »

Post #1 continued:

103 Stroker Power - by Joe Minton American Rider October 24, 2005

Note:

For those of you who are not familiar with Bill's reference to my earlier Twin Cam 88 recommendations, let me give you a brief recipe:

* Change the cam design to one that closes the intake at near 30-degrees after bottom dead center (ABDC). This starts real power at or near 2500 rpm which is 55 mph in top gear. Either the Screamin' Eagle 204 with a Crane 4-degree advance engine sprocket or an Andrews TW21 performs well. My JM20 cam set is no longer available as Bartels' Performance Products has not ordered any from Andrews for some time now.

* Fit a Screamin' Eagle or similar free flowing air filter. Avoid those filters that have the air turn corners or that directly expose the filter element to the air stream. The Screamin' Eagle, Rivera "Smoothie" or Arlen Ness "Big Sucker" are good examples.

* Use the stock header pipes or pipes that have the same length and diameter.

* Fit mufflers with free-flowing baffles. If you like the traditional shorty dual mufflers then use old style (loud) Screamin' Eagle slip-ons or the same thing from Cycle Shack. For touring riders, there is no better than the SuperTrapp touring mufflers with the performance baffle set; this is the same as Screamin' Eagle touring mufflers & SuperTrapp baffle set mentioned earlier.

* If your engine is one of the carbureted versions, fit a Mikuni HSR45 with the Mileage Kit (Fox Distributing, near Chicago (630) 513-9700. This carburetor greatly improves throttle response and ups peak power between five and seven HP.

* If you have EFI, then you might use the Screamin' Eagle Race Tuner kit or a Power Commander from Dynojet to get the mixtures just right. Stock 'jetting', carbureted or EFI, is very lean in the 20 - 40% throttle range and become more so after the air cleaner and muffler changes. You must re-tune the EFI after the modifications.

These modifications are simple, relatively inexpensive and extremely effective. Hundreds of owners have modified their engines to these specifications and none that I know of has regretted the changes. These moderately altered engines have a very wide power band, much wider than stock. It starts at about 2200 rpm and extends past 6000 rpm. They are also more tractable and pleasant to use than stock. Passing or climbing power in top gear is remarkably improved and a Harley with such an engine will generally blow the doors off most big-cam, high-hor$epower bikes in a top gear roll-on.

BaggerDad · « **Reply #2 on:** February 18, 2006, 01:23:11 PM »

For 95" builds looking for low-mid rpm TQ, Joe Minton of American Rider recommends the following:

Joe Minton

Unbalanced · « **Reply #3 on:** February 18, 2006, 07:36:50 PM »

Go ahead try it the problem isnt the motor in this case its the flowing of the heads. The question becomes what pistons are you going to run flat tops or 10.5 to 1's. You have to decide this before you can choose a cam. If you run the37g with 10.5 to 1's you will detonate badly if you run the flat tops and ride 2 up then 37g is fine if you ride 1 up and use flat tops you can use the 26g if you ride 2 up and want to use the 10.5 to 1 pistons you should look at the 31g I believe it is. Lots of questions only problem is without the supporting information its hard to just say here.

BTW while the joe minton article is fair information. It is not as applicable on this site, because most of the bikes here are the CVO 103 engines, The article is really only applicable when the heads are the 103 bathtub style heads that are not hemi design.

Some other information you might find handy is check out the new bolt in from Zippers it has the highest power bolting into a stock 103 from 2500 to over 4000 rpm. Its the 575 will be available gear drive / chain drive. It has over 90 at 2000 and almost 100 at 2650 and holds it flat for a bolt in cam. Others exceed it, but remember its not a gear drive in the test.

-harry

DCFIREMANN · « **Reply #4 on:** February 19, 2006, 08:41:51 AM »

I would not run either one of these cams in a stock CVO103 motor. As Harry pointed out the HEADS and the HUGE COMBUSTION CHAMBER. The chambers are so big you can drive a Mack Truck in them and the compression is aprox 8.7 to 1. These heads will work but need a lot of help. After the combustion chamber issue is taken care of you are opened up to run a very large selection of cams that are on the market. JMHO. Not bashing the article but it was driven towards a TC 88 motor not a CVO 103 and there is a difference.

Be Safe

THE DAWG

BaggerDad · « **Reply #5 on:** February 19, 2006, 06:49:21 PM »

Points well taken.

kng103 · « **Reply #6 on:** February 20, 2006, 10:55:16 AM »

Quote

Points well taken.

BaggerDad · « **Reply #7 on:** February 20, 2006, 07:29:54 PM »

Kng103

I'm assuming you put the 103 stroker flywheel and rod assembly p/n 236900-00 in your 2004 Road King Classic. Sounds along the same lines as what I want to do. 100 ft lbs at 2500 is my target goal if not less. How long does the TQ curve stay above 100 ft lbs?

What heads did you use - combustion chamber size, head gasket size?
What pistons did you use, the SE Pro TC Flat Top STroker Piston p/n 22942-00?
What is your compression ratio?
The SE-251 has an intake close of 46 degrees - better for low rpm TQ than the stock CVO cam with a 53 degree intake close.

And if you have a copy of your dyno sheet kelvinrosey@comcast.net.

kng103 · « **Reply #8 on:** February 20, 2006, 10:28:18 PM »

Quote

Kng103

I'm assuming you put the 103 stroker flywheel and rod assembly p/n 236900-00 in your 2004 Road King Classic.

BaggerDad · « **Reply #9 on:** February 21, 2006, 08:46:41 AM »

Thanks KNG103

I found the SE 103" kit p/n 29842-03 $2500.00.

This is what I found to piece meal a 103". Ordering the HD parts from Hale's or Zanotti's HD would save 20% on HD parts.

$1000.00 HTCC heads (p/n 16933-99B)
$1325.00 SE Pro Stroker Flywheel & Rod Assembly
$280.00 SE Forged Stroker Pistons P/N 22444-02 (For 10.5:1 CR)
$390.00 Woods TW-6HG cam or Woods TW-5G (I have the 4 gears necessary for gear cams)
$75.00 Woods Compression Releases (pair)

The Woods Performance Carburetion site: http://www.woodcarbs.com/dynoruns.htm
has 103ci stroker dyno runs.

Steve_G · « **Reply #10 on:** February 22, 2006, 01:02:19 PM »

I also respect Joe Minton's opinions. The thing I can't figure out though is exactly which cam I should use. I also am looking for low to mid-range torque, and I want to go gear drive- which I have in my 95 in. Heritage Softail. I e-mailed Andrews Products, and I was told the 37g was the way to go, but I'm not sure about the 30 degree cam closing that is recommended by Minton. I'm sticking with my stock headers and have ordered a set of Rush mufflers with 2" baffles. I'll either go with the Doherty PowerPACC or the new K&N RK series air filter kit. (By the way my bike is a new SE Ultra). I really like the stock exhaust, but the only way to change the baffles is to un-weld them. I have been told that once they are "butchered" there's no going back. If someone has figured out how to use the stock mufflers and do the baffle switch that Joe has recommended I'd sure like to hear about it. I figured I'd just store my stock mufflers away in case the powers that be decide to clamp down on us all for changing such things. I'm going to try the Rush mufflers because you can change the baffles. I have not been able to find anyone with a CVO bike that has tried these, but you pays yer money and takes yer chances- right? I think I'm going to leave the stock cams alone until I'm totally certain that I have enough info to make the right cam choice to get the "torquer" bike that Joe describes. I want the good mileage, and I don't want loud pipes either. After all, this is a touring bike.
I guess I'll just keep checking this web site and reading all the opinions until I feel comfortable switching cams. If there are members of this discussion group that feel the same, about Joe Minton's opinions, I'd like to hear what they have done to get his results. I notice that Donny Peterson from Heavy Duty Cycles is adamant about going gear drive for the cams, but Minton never mentions anything about it in his articles. I wonder why?

[smiley=jalapeno.gif] [smiley=drink.gif] -Steve G

Unbalanced · « **Reply #11 on:** February 22, 2006, 05:00:48 PM »

Steve G,

While respecting his opinions is great the issue is your heads arent in a shape he is talking about so to just go ahead and do a cam swap, because you want X desired effect is umm without merit. First figure out what your going to do with the heads to help with air flow, because while these heads are 94cc stock the flow in the sucks, the firing position is in a poor place and that is just getting started. If your going anywhere away from stock as it is you will need to address the heads first having done that it will point you in a direction of what cam to run. Until you get these things ironed out your just firing money and taking your chance.

Joe Minton does NOT have an expose on Hemi Style heads and until he does to match your new Ultra and what comes on it your taking information out of context and will only cost you more money to fix it in the long run if you want it right.

To be honest until I actually get the heads back from Zippers I can not comment on if its possible to make these heads work and get great numbers without welding them up. Zippers believes they have it licked and have sent me the necessary supporting documentation, but until I mix that information with the cam / throttle body I won't have any better answers.

The heads have been CNC'd to 105 cc and are to be used with the 10.5 to 1 pistons from Harley yeilding a 10.0 to 1 compression ration derived from the extra CC in the heads and cam choice.

Power kit 103

Total compression ratio is 10.0 to 1 using SE high compression pistons which require no second op work.

Unbalanced · « **Reply #12 on:** February 22, 2006, 05:02:47 PM »

Steve G,

In your 95" go with the 55g just keep the compression under 10 to 1 and it will pull like a freight train. The concerns you will need to look into is the spring lift, the 55g is 550 lift.

-harry

Street Stalker · « **Reply #13 on:** February 23, 2006, 09:02:56 PM »

Quote

To be honest until I actually get the heads back from Zippers I can not comment on if its possible to make these heads work and get great numbers without welding them up. Zippers believes they have it licked and have sent me the necessary supporting documentation, but until I mix that information with the cam / throttle body I won't have any better answers.

The heads have been CNC'd to 105 cc and are to be used with the 10.5 to 1 pistons from Harley yeilding a 10.0 to 1 compression ration derived from the extra CC in the heads and cam choice.

Power kit 103

Total compression ratio is 10.0 to 1 using SE high compression pistons which require no second op work.

Unbalanced · « **Reply #14 on:** February 23, 2006, 10:57:47 PM »

Your Welcome Street Stalker.

They just told me first day of bikeweek I should be able to pick up my heads from them at their trailer

boy oh boy that means maybe tuesday the bike will be a runnin ... I feel a long hard day of cruising will be in order to get past the break in ....

DCFIREMANN · « **Reply #15 on:** February 24, 2006, 07:26:46 AM »

HARRY the stock springs are not going to be used and the valve size was increased. I will have some pics tomorrow I hope as with some more info.

Be Safe

THE DAWG

Unbalanced · « **Reply #16 on:** February 24, 2006, 08:44:56 AM »

I know they changed the intake size, 2" intake / 1.625 exhaust" Dan hadn't made a final decision yet on the springs as of 3 days ago and he wants me to swap the cam again. I will be glad when they get delivered and I can give em a go.

See previous post from Specs from Dan.

Power kit 103

Total compression ratio is 10.0 to 1 using SE high compression pistons which require no second op work.

kbiforce · « **Reply #17 on:** March 01, 2006, 10:54:17 AM »

Baggerdad, you have a PM.

RATMAN · « **Reply #18 on:** March 06, 2006, 08:42:42 PM »

I'd like to see your dyno sheet when you get done.I will try to attach mine to this reply.Ratman

nidan · « **Reply #19 on:** March 17, 2006, 07:14:04 AM »

For a 103 look at Woods 400G

DCFIREMANN · « **Reply #20 on:** March 17, 2006, 08:42:23 AM »

Quote

For a 103 look at Woods 400G

Very good numbers, but what is the compression and what heads?

I have had a set of these laying around for a while but there had been toooo much talk about valve train noise on other sites. So I ended up going in another direction.

Be Safe

THE DAWG

nidan · « **Reply #21 on:** March 18, 2006, 07:35:20 AM »

Good question , Bobby doesn't give many details , but has a great rep. While I didn't go with his cams , he was patient, courteous, very thorough and helpful when I was looking at cams.

Steve_G · « **Reply #22 on:** March 21, 2006, 12:24:14 PM »

I thought this thread was a question about a choice between two cams. the TW26 or the TW37. I haven't seen too much in the way of direct responses to this question. Instead I see responses to all the different cams someone is using. That's great, but should these type of responses be posted on a different thread?

-Steve

kbiforce · « **Reply #23 on:** March 21, 2006, 09:02:55 PM »

I posted my dyno sheet on the Eglide dyno numbers thread. I used the TW37 advanced four degrees.

nidan · « **Reply #24 on:** March 22, 2006, 08:13:44 AM »

Regarding the TW 26 - if using stock heads/compression it's a nice cam, good low end .

If using compression up to 9.8 and higher flow heads the TW37 will produce better power across the range.

If exceeding 9.8 and you want to stay with a similar cam , the TW31 will easily handle 10.5 same lift as the 37 , comes on lower (1800) .

I'm running a TW31G and love it.

I'd certainly consider other cam choices , talk with Andrews , Woods, and your wrench.

Author Topic: In a 103" use TW26 or TW37? (Read 9964 times)