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I was just looking at the HP inc website and they had a comparison between stock TB's and their units. It said the stock MM throttle body flows 215 cfm @ 10" and the stock Delphi flowed 178 cfm @ 10". If that is accurate then why is the Delphi better?
 

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95FLHR said:
I was just looking at the HP inc website and they had a comparison between stock TB's and their units. It said the stock MM throttle body flows 215 cfm @ 10" and the stock Delphi flowed 178 cfm @ 10". If that is accurate then why is the Delphi better?
The Delphi system is better because it has more sensors, like anti-knock, than the M&M system, and is easier to tune. The M&M TB is a dual runner, one intake for each cylinder, and the Delphi is a single. Hence, the M&M flows more.

That's my understanding, but I have been wrong in the past.
 

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MM vs delphi :whisper:
I agree that delphi is better flowes more and more sensors all good, but....... MM with dual runners has less reversion..... easier to tune my exp.:nope:

Good Luck

Steve The Dyno Guy :cheers:
 

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Steve Handy said:
MM vs delphi :whisper:
I agree that delphi is better flowes more and more sensors all good, but....... MM with dual runners has less reversion..... easier to tune my exp.:nope:

Good Luck

Steve The Dyno Guy :cheers:
Steve,

I live in Los Angeles. You in Lake Havasu. Is Laughlin the closest you will ever get to being out my way? Do I need to make an appointment to see you at Laughlin for a dyno run/tune?
 

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If you search "individual runner" you will see why the IR needs much larger runners to get the equivalent flow of an open common plenum setup. Airflow on a flow bench is not the true full story. Ever wonder how good running 2 liter 4 cylinder motors use two 45DCOE webbers and are not overcarbureted. Ever wonder how Mike Roland and Doug Lofgren got a 1200cc Buell to make 134 streetable HP with dual Super E carbs? Problem is the MM TB can't be big enough as the turn radius at the head is way too restrictive regardless of the TB opening. Take alook at one in your hand and you will see what I mean. You will find the rare OC soul that has squeezed 100hp out of one. My hats off to them but I also say theres 10 more bolt on hp in there with just a TB change. I would have BC Gerolomy or Dakota kid open up even a stocker. These changes need to be made before tuning.
 

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nw_guy4_fun said:
If you search "individual runner" you will see why the IR needs much larger runners to get the equivalent flow of an open common plenum setup. Airflow on a flow bench is not the true full story. Ever wonder how good running 2 liter 4 cylinder motors use two 45DCOE webbers and are not overcarbureted. Ever wonder how Mike Roland and Doug Lofgren got a 1200cc Buell to make 134 streetable HP with dual Super E carbs? Problem is the MM TB can't be big enough as the turn radius at the head is way too restrictive regardless of the TB opening. Take alook at one in your hand and you will see what I mean. You will find the rare OC soul that has squeezed 100hp out of one. My hats off to them but I also say theres 10 more bolt on hp in there with just a TB change. I would have BC Gerolomy or Dakota kid open up even a stocker. These changes need to be made before tuning.
I know we have discussed this before but I have a couple of questions re the bored MM/TB. You say 10 hp with the bored TB but I have read that all the gains are only on the top end and that it may have a negative effect on the lower end tq(ie flat spot/dip) can you tell me about this in real basic terms, I have a hard time getting my brian around this whole thing no matter how many different ways it's explained to me...
Thanks, adx
 

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Agree with Steve Handy here. Dual runner TB's are easier to tune and tend to be smoother running, especially in the low end. You can literally separate the v twin into two separate tunes for each cylinder. And it is the electronics in the Delphi that make it a more accurate and reliable system. Our best builds have been with the Delphi electronics and dual runner TB.
 

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Very simply in an EFI port fed motor pressure differential is not used to draw in the fuel as it is a carburetor so a slightly OS TB can not hurt you. Too big of a carb will kill the response down low. Cams, exhaust, ports, valves, timing all will have the major influence on the power band. If the TB is restrictive or undersize it can just hurt you. Kuryakyn has a 95" test mule dyna with a 57mm TB (correct me if I am wrong I believe that is their size) and mild cams TC26G, and their heads, mild compression, making
120+hp with a big fat torque curve over [email protected] 2500. If a TB is too big it can make tuning a challenge but it will not hurt power or torque.

Flames ON, I am sure.
 

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nw_guy4_fun said:
Very simply in an EFI port fed motor pressure differential is not used to draw in the fuel as it is a carburetor so a slightly OS TB can not hurt you. Too big of a carb will kill the response down low. Cams, exhaust, ports, valves, timing all will have the major influence on the power band. If the TB is restrictive or undersize it can just hurt you. Kuryakyn has a 95" test mule dyna with a 57mm TB (correct me if I am wrong I believe that is their size) and mild cams TC26G, and their heads, mild compression, making
120+hp with a big fat torque curve over [email protected] 2500. If a TB is too big it can make tuning a challenge but it will not hurt power or torque.

Flames ON, I am sure.
THANKS! I still don't really understand it but for my level of understanding, your explaination was perfect!
Another question if you don't mind. You are the only one who has mentioned Arlin at Full Throttle Dyno to me several months ago and I have been reading some of his stuff and pretty sure he really knows what he's doing. Does your reccomendation still stand? My thought is to break the bike in with the propipe and stock TB and a canned map for my PCIII then take the bike to Arlin and have him install the Gerolamy and the RB/LSR at the time of the dyno. How does that sound to you? Gonna call him about this next week cuz my bike and all the parts are already sitting at builders waiting for me to give the go ahead.
Thanks again for your input!
adx
 

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ADX
Sounds like a good plan to me. Arlin is one of the few that I would trust. He takes the time too get it right and cares. A few things I have found. The PC has issues with the first USB PCIII and need new firmware. If yours was not recently purchased you can call them for details. Get that fixed first as it will affect the tuning. Also this guy (email below remove the "at" and insert @) has a HPinc 53mm throttle body for sale reasonably if interested. I put this same unit on a 95" build and watched it gain 10hp with no loss of response. The Gerolomy is a good choice too but this will pull harder on the top.
mjmillar at mts.net, Mitch
 

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nw_guy4_fun said:
ADX
Sounds like a good plan to me. Arlin is one of the few that I would trust. He takes the time too get it right and cares. A few things I have found. The PC has issues with the first USB PCIII and need new firmware. If yours was not recently purchased you can call them for details. Get that fixed first as it will affect the tuning. Also this guy (email below remove the "at" and insert @) has a HPinc 53mm throttle body for sale reasonably if interested. I put this same unit on a 95" build and watched it gain 10hp with no loss of response. The Gerolomy is a good choice too but this will pull harder on the top.
mjmillar at mts.net, Mitch
Thanks! I already have the Gerolamy unit and cash is a big issue for me, my pcIII is a R, not a usb and again, it'll have to do. If it won't do, I'd just go to the SERT now that it's finally offered for MM.
I'll give arlin a call first of the week, I'll let you know what his input is.
Thanks again for your help, adx
 

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guy4 fun is correct in that efi is not like a carb. Mike Roland and Doug Lofgren made an exact copy of the WT throttle body only 52mm, bolted it on a bike ran it on the dyno, then bolted up an off the shelf WT 57mm throttle body, put it back on the dyno and you could lay one graph on top of the other. Virtually identical. Almost impossible to go too big on a TB.
 

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adx
Because Arlin is your tuner the PCIII is the best choice and the R is fine. He uses direct link and the dyno communicates the same way as USB but through a serial port.
Good plan!
 

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Paniolo said:
Steve,

I live in Los Angeles. You in Lake Havasu. Is Laughlin the closest you will ever get to being out my way? Do I need to make an appointment to see you at Laughlin for a dyno run/tune?
Paniolo, During Laughlin week I set up at Mother Road Harley Davidson in Kingman Az last year I was VERY BUSY, one guy waited 3 hours.... (most wont wait that long) apt good idea , but you are only 4 hrs away Havasu is a nice town to visit . why wait call me 928-486-9193 or ck Post (got mine dynoed today in E F I mapping section ) ~!Awesome!
Good Luck
Steve The Dyno Guy :cheers:
 

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nw_guy4_fun said:
ADX
Sounds like a good plan to me. Arlin is one of the few that I would trust. He takes the time too get it right and cares. A few things I have found. The PC has issues with the first USB PCIII and need new firmware. If yours was not recently purchased you can call them for details. Get that fixed first as it will affect the tuning. Also this guy (email below remove the "at" and insert @) has a HPinc 53mm throttle body for sale reasonably if interested. I put this same unit on a 95" build and watched it gain 10hp with no loss of response. The Gerolomy is a good choice too but this will pull harder on the top.
mjmillar at mts.net, Mitch
I tried to email you but your box is full.........I am interested if the port size at the manifold is ok (1.66) .........(1.71) is too big for my application.

I email the guy...........so will wait and see

All the best, Ozzie
 

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nw_guy4_fun said:
OZ
Mailbox fixed, it is a 1.660 and it is not mine but belongs to Mitch, his email address in the last post.
Thanks for that, I have emailed the guy so will see what happens.................

Just as a matter of interest.........the 53mm T/Body actually shows an improvement in torque over the 51mm. T/Body with my build and configuration of parts..................so the statements by Mike Roland and Co in regard to EFI T Body sizes would appear to be correct.

Again, heads, and pipes play a big part of getting the numbers correct and then it is up to the tuner to pull out the last drop of power.

All the best, Ozzie
 
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