getting open end cap...remove how many discs?

[skyhook]

most of y'all know my build, but I'll rehash for those who don't

'08 dyna 110"...r&r stage 4 heads....030 hg's...200ccp/4% leakdown...se257 cam...hpi55mm...se injectors...advance tune w/ pc3...supermeg...wood 3.25 a/c...current;y running 28 discs/closed end cap...gonna try open cap...how many discs should I remove?

[roadglide65]

how many discs should I remove?

10 to 12 discs is what I would start with.

[Sailor285]

Stock open end cap Supertrapp says is equivalent to 10.. Billet open end cap 8

[happyman]

most of y'all know my build, but I'll rehash for those who don't

'08 dyna 110"...r&r stage 4 heads....030 hg's...200ccp/4% leakdown...se257 cam...hpi55mm...se injectors...advance tune w/ pc3...supermeg...wood 3.25 a/c...current;y running 28 discs/closed end cap...gonna try open cap...how many discs should I remove?

super trapp says the open end cap =10-12  discs

[fuzznut5197]

Somewhere I have an old Supertrapp chart showing what equals what. They go by "equivalent area", so when they say an open end cap means so many disks, they are comparing the open end cap's hole in square inches to the amount of disks needed to equal that area. But it's always approximate, because the disc area is influenced by how much you torqued the bolts, carbon, age, etc.

[tdrglide]

I run open end cap and 18 disks on my axtell 110" 195ccp, t-man 590 cams, 48mm throttlebody, stock injectors, pcIII ......ect. Well manered sound at idle and cruise but can bark some when you jump on it. 115tq 112hp with 105tq at 2800rpm and 105tq at 5400 rpm. And still needs some tuning I think
This is an open end cap from summit racing. Not no end cap

[skyhook]

thanks for the help...will try removing 10 discs when we install the open cap...then test on the dyno...main thing I hope to gain is to cool the motor...and second is that the hp falls off at 5800 but would like it to pull to 6200...hopefully the closed cap is the choke...if not, we'll try a larger exhaust...boarzilla is first on the list

[roadglide65]

thanks for the help...will try removing 10 discs when we install the open cap...then test on the dyno...main thing I hope to gain is to cool the motor...and second is that the hp falls off at 5800 but would like it to pull to 6200...hopefully the closed cap is the choke...if not, we'll try a larger exhaust...boarzilla is first on the list

Looking forward to what you find out. IMO I would not be to quick to jump to the boarzilla not enough CI in your setup.

I have a similar motor that I run a FatCat with S/T muffler just never tried the closed end cap on any of my set ups. So I look forward to seeing if there is much of difference.   

[skyhook]

I understand torque would suffer with boarzilla...this is a bobbed dyna and I'm about 175#, so the trade-off may be worth it

[Deye76]

I run open end cap and 18 disks on my axtell 110" 195ccp, t-man 590 cams, 48mm throttlebody, stock injectors, pcIII ......ect. Well manered sound at idle and cruise but can bark some when you jump on it. 115tq 112hp with 105tq at 2800rpm and 105tq at 5400 rpm. And still needs some tuning I think
This is an open end cap from summit racing. Not no end cap

How do you like that T-Man .590 cam? Quiet?

[tdrglide]

Horsepower starts to fall off between 5800 and 6000 rpms on my set up. 18 disc and open end cap

T-590: quiet cams is a relative term, but I think they are quiet enough

[tdrglide]

What I meant was hp peaks between 5800 and 6000 rpm. Hey but it's a bagger

[happyman]

I understand torque would suffer with boarzilla...this is a bobbed dyna and I'm about 175#, so the trade-off may be worth it

you  a decnt build ,and will handle the  borezilla ,if you make sure you have the quite baffle. otherwise  it will be giving up a little dip for a split second. if you happen to be running at the low rpm

[skyhook]

thanks fellas

my valvetrain is very loud, too...don't think there was much blueprinting done...but hey, 10k miles and hasn't blown up yet...and if it does, 117 to follow!

[happyman]

thanks fellas

my valvetrain is very loud, too...don't think there was much blueprinting done...but hey, 10k miles and hasn't blown up yet...and if it does, 117 to follow!

so you gonna get new cases?? going to be tuff to do a 117" on the 110" case with the  groove for the base gasket.
Happy

[skyhook]

true, the case bore boogers up the o-ring groove...requires new cases like you say OR cylinders with an offset on the bottom to match the boogered cases

[sean fxd]

<<so you gonna get new cases?? going to be tuff to do a 117" on the 110" case with the  groove for the base gasket.>>

Can you explain this for me.  If I understand this correctly, the Axtell 4 1/8 jugs for the 117 use a base gasket and the cases have to be bored out a little more than the 110.  So how would anything done to the cases for a 110 stop you from doing a 117?

Thanks,

Sean

[skyhook]

I ain't the best technical writer, but I'll try...when the cases are bored for the bigger cylinders, you lose the outer ledge of the o-ring groove...now you no longer have a solid surface for the cylinder to sit on...now, if you were to build a cylinder with an offset on the bottom which matches the boogered case surface, you're golden

[sean fxd]

<<when the cases are bored for the bigger cylinders, you lose the outer ledge of the o-ring groove...now you no longer have a solid surface for the cylinder to sit on...>>

I get that.  I just don't understand the comment from happyman that implies that because you have bored your cases for a 110 that you could not do a 117.  Don't you have to bore your cases even MORE for the axtell 4 1/8 jugs?  There are thousands of Axtell 4 1/8 jugs on bored OEM cases and they work fine with the base gaskets.

Sean

[happyman]

<<when the cases are bored for the bigger cylinders, you lose the outer ledge of the o-ring groove...now you no longer have a solid surface for the cylinder to sit on...>>

I get that.  I just don't understand the comment from happyman that implies that because you have bored your cases for a 110 that you could not do a 117.  Don't you have to bore your cases even MORE for the axtell 4 1/8 jugs?  There are thousands of Axtell 4 1/8 jugs on bored OEM cases and they work fine with the base gaskets.

Sean

ahhhh, i never implied he bored his cases for a 110" they come that way  on a cvo 07 and upl  you find a good shop  that can set things up you can weld them up and machine them to perfection.  then build the  117"     
     Happy

[skyhook]

installed open end cap and removed 8 disc...sounds badazz and 'round the parking lot, doesn't seen to have lost any tq...test and tune next am

[skyhook]

went for 30 minute ride and I like it...couple months ago a few folks insisted that open is better than closed...not sure if it was the beer or if it actually does pull better...dyno will tell the tale tomorrow...

[Jeffd]

my butt dyno likes the open end cap better.  I think it sounds better too.

[skyhook]

bad air today...gonna tune this weekend

[Shadowdog]

my butt dyno likes the open end cap better.  I think it sounds better too.

I'll second that on my 1200S Sportster. waiting to see where the economy goes before the Dyna gets a black ceramic Supertrapp.

Best,

Shadowdog[/color]