HOW BIG OF TB DO YOU NEED FOR YOUR MOTOR? INFO HERE.......

[FLTRI]

Do tuners have a hard time with "dual throat" set ups? Is it that they don't work well on a short Y manifold? Remember the S&S 2 throat?

Actually makes no difference to me as far as tuning as long as it was done correctly, especially as to the MAP sensor. Since the MAP sensor is looking for common manifold pressure the the 2 runners must be made common for the right signal to get to the ECM.

[Don D]

Do tuners have a hard time with "dual throat" set ups? Is it that they don't work well on a short Y manifold? Remember the S&S 2 throat?

Yep I have used the S&S before and got it to work fine on my old superglide, kind of like the HD Holley much maligned and misunderstood, not bad. I can't remember if the S&S was true IR though and the Holley was not.
One problem with tuning the IR with a Delphi ECU is the MAP sensor needs to be from a common 2 cyl source and the BC Gerolomy setup is not but would be easy to adapt. Also the BC unit uses a non-standard TPS IIRC. DTT Wego II or III can negotiate the single cyl. MAP signal and the BC TB TPS, not sure about Tmax.
IR changes the whole ballgame and what may seem like way too big is not due to the manifold pulsation and time between intake cycles. Take a look at an old Ferrari V-12, tiny motor and see the 6 -2 barrels. It works very well and even though this is a dual OHC motor it is not that high rpm. I know OT sorry.

[PanHeadRed]

DH's, I did not get into detail as to how, and why, I just listened as he briefly talked, he was just getting into the conversions and had done 2 maybe three. I will talk with him when I can, and see how it panned out.

[skyhook]

just came back from french qtr, rippin' all the way...good air here and I LIKE it!...gofast here's my sheet...really a mild build...110"... '08 ...570 lift cams ...200ccp...pump gas...5th gear...dj250...sae...I've put 9.5k miles on it in 13 mos

[attachment removed after 60 days by system]

[roadglide65]

just came back from french qtr, rippin' all the way...good air here and I LIKE it!...gofast here's my sheet...really a mild build...110"... '08 ...570 lift cams ...200ccp...pump gas...5th gear...dj250...sae...I've put 9.5k miles on it in 13 mos

If we could postpone this till spring when I get out of all this cold weather I would love to see what what my 110" would do against yours    I'm always up for a good Crayfish Boil and some good Cajun food.

OH and I've only put 12000 on mine in 7 months 

[mtnmotorrider]

That's "craw fish" boil, and Coon Ass food, if you use the proper vernacular!   

[roadglide65]

That's "craw fish" boil, and Coon Ass food, if you use the proper vernacular!   

You know I new I knew I screwed up as soon I posted it. Like I've been told time and time again it not peeee can pie phacan pie.

That's the problem with letting these yamdankes coming down there.   

[Sonny S.]

As I explained in post: "Through that testing we discovered the rear got the cooling fuel feed while the front was going lean."

Here's a little something to consider:
Take a typical HD V-twin as used in a drag race. When the bike launches off the line the intake track's AF mixture is moving perpendicular to the track while the bike is talking off. Which cylinder will get favored with more AF mixture? Also there is more fuel stuck to the rear cylinder part of the manifold.
Now put a 200hp v-twin in the same situation and the problem is exacerbated, big time. When the bike launched the front cylinder went lean and the rear went rich.....until 60ft, then you saw the g-forces wane and the AF balance start to normalize and by 1/8 mile the AFR was fairly balanced. We know it was happening this way becasue it did not exhibit that anomoly on the dyno.

This is but just a small bit of what can be learned from measuring what actually happens.

So why does this happen with mainly 2-1 systems?

[Deye76]

Do tuners have a hard time with "dual throat" set ups? Is it that they don't work well on a short Y manifold? Remember the S&S 2 throat?

Yep I have used the S&S before and got it to work fine on my old superglide, kind of like the HD Holley much maligned and misunderstood, not bad. I can't remember if the S&S was true IR though and the Holley was not.
One problem with tuning the IR with a Delphi ECU is the MAP sensor needs to be from a common 2 cyl source and the BC Gerolomy setup is not but would be easy to adapt. Also the BC unit uses a non-standard TPS IIRC. DTT Wego II or III can negotiate the single cyl. MAP signal and the BC TB TPS, not sure about Tmax.
IR changes the whole ballgame and what may seem like way too big is not due to the manifold pulsation and time between intake cycles. Take a look at an old Ferrari V-12, tiny motor and see the 6 -2 barrels. It works very well and even though this is a dual OHC motor it is not that high rpm. I know OT sorry.

An engine builder I know had one(S&S 2 throat) on his 93" shovel. He got it to run good after he removed the wall in the manifold.

[jmorton10]

MAN!  I love that bike!  Sorry.... off topic... back to our regularly scheduled program...

Me too, here was my first around 1970

http://www.pbase.com/jmorton10/image/23429104

5" stroke, 92 inches with stroker plates......

Started as a stock 1957 Police Pan......

~John

[GoFast.....]

MAN!  I love that bike!  Sorry.... off topic... back to our regularly scheduled program...

Me too, here was my first around 1970

http://www.pbase.com/jmorton10/image/23429104

5" stroke, 92 inches with stroker plates......

Started as a stock 1957 Police Pan......

~John

That is a beautiful rigid pan head, Nice enought to be in a mag. I forget, What kind of Carb is that

[FLTRI]

Looks suspiciously like an SU? LOL!

[hrdtail78]

If I was on the fence of a larger TB or not.  I would start by looking at the fitment of the stock TB.  Some of them fit terribly.  When assembling an engine (trying to stay with correct, accepted terms) I perfer to have the TB or manifold handy rather than at the customers house.  My point being this.  A smaller TB with correct port matching will deliver a better slug of air into an engine over a bad port matching slightly larger TB.

[FLTRI]

If I was on the fence of a larger TB or not.  I would start by looking at the fitment of the stock TB.  Some of them fit terribly.  When assembling an engine (trying to stay with correct, accepted terms) I perfer to have the TB or manifold handy rather than at the customers house.  My point being this.  A smaller TB with correct port matching will deliver a better slug of air into an engine over a bad port matching slightly larger TB.

Boy do I agree!
Port matching is as old as the hills yet is ignored by some shops yet, IMO is absolutely necessary to do a proper job IMO. After all the customer is hiring a shop (indy or dealer) to do performance work. IMO performance work cannot be accomplished properly with mismatched port to intake manifold fitment.
Kinda real basic to the definition of performance.

[GoFast.....]

You can open the butterfly by the throddle and use a flash light and see if they match. With the older two peice and Carb manifold you can stick your finger in there and check to make sure they match.

[Hoist!]

Youze are all talking about peak numbers and small gains from changing TB size. So you can argue that all day! What about the rideability?  Is that not a seat-of-the-pants REAL performance gain too? On my hot rodded 110, it was designed for a 58mm HPI TB and used it with a Doherty Power Pakk A/C. Peformed very well at peak, but had a dip and ramped up at low RPM's. We tested some things, one of which was going to a 62mm HPI TB with their hi flo A/C. Not much difference on peak numbers, but it cleaned up the whole bottom, and raised TQ substantially, and straightened up the curve in the lower RPM range. Went from 89 Ft-LBS @ 2000 to just over 100! You bet your ass TB selection is important!

Hoist!

[Admiral Akbar]

Well so much for smaller being higher velocity and making more low end torque..  Max

[Hoist!]

Well so much for smaller being higher velocity and making more low end torque..  Max

All depends on the flow characteristics of the top end. The CVO 110 needs GOBS of flow to wake it up. Unless you modify the heads by welding the ports, changing valve size, and increasing that velocity throughout, the increased velocity in 1 area doesn't really do much for ya. Match the flow characteristics of the heads with the rest of the intake, exhaust, and cam timing, and you have a whole new ballgame! Most have not tested or embraced the 110. I love mine! But I'm not talking HD's POS stock 110 either here, but a slightly modified version thereof!

Hoist!

[Admiral Akbar]

Well,

I guess it's OK as long as Donny didn't work on it..  Max

[Hoist!]

Well,

I guess it's OK as long as Donny didn't work on it..  Max

HeHe!!! OK! Well Donny didn't, whoever that is!

Hoist!

[geezerglide]

Well,

I guess it's OK as long as Donny didn't work on it..  Max

HeHe!!! OK! Well Donny didn't, whoever that is!

Hoist!

Hoist,

I am assuming MaxHeadflow is referring to Donny Petersen, but I could be wrong.

Its good to see you over on this board, I see you more frequently. lately.

geezerglide

[Hoist!]

Well,

I guess it's OK as long as Donny didn't work on it..  Max

HeHe!!! OK! Well Donny didn't, whoever that is!

Hoist!

Hoist,

I am assuming MaxHeadflow is referring to Donny Petersen, but I could be wrong.

Its good to see you over on this board, I see you more frequently. lately.

geezerglide

He geezer, didn't know you were over here too! Thanks for saying hey! Just signed up yesterday! Very cool tech site. I'm glad Coyote steeered me over here! I thought he mighta been referring to DP, but still trying to get a flavor for personalities here. So, not sure if something's sarcastic yet,  I'll err on the side of caution! (for now anyway!)

Hoist!

[GoFast.....]

Welcome to the best Harley Tech Site on the internet

[Admiral Akbar]

HeHe!!! OK! Well Donny didn't, whoever that is! 
Hoist!

Hoist,

I am assuming MaxHeadflow is referring to Donny Petersen, but I could be wrong.

Its good to see you over on this board, I see you more frequently. lately.

geezerglide

Heck I you don't know who Donny is then you're all right in my book..  Max

[Don D]

Unless you modify the heads by welding the ports, changing valve size, and increasing that velocity throughout

Or just take a set of the old tried and true 99-04 TC stock heads and rework them, no welding needed, bigger valves are needed however to feed that motor that is 25% bigger than what the heads were designed for. The 110 heads can be made to work well too without welding. This has been discussed on the CVO forum