I have a 2003 Dyna FXD, put in a 98" Big Bore kit 2 years ago. 9.8:1 CR, stock heads Andrews 31 cams. It has 2-1 VH Pro-Pipe, High Flow AC, Carb re-jetted, upgraded ignition module, timing is set at 32 degrees. HP is ~90, TQ is 100ft/lbs. I want more without going to 124 but I will if I have to. Would different heads/cams or headwork give me that much more to be worth it or should I just go to 124". This bike is ridden solo only. Thanks.
quality headwork, done to your recipe is always money well spent....
Heads cam and carb,you can't beat a 124 though :fish:
It's like this, can you afford to make yours a 124", and upgrade the required items to support the 124" motor? If yes, then the answer is do it.
If no, then head work, more cam, more compression, better carburetor, programmable ignition, tuned on a dyno or add AFR reading equipment. But dyno is generally better.
The right guys heads and matched parts, you're likely to see 115 / 115, or more if you push the envelope with the motor setup.
First thing on any vehicle is to make sure your gear ratio is optimized. You wouldn't put a 3 to 1 rear end in a 1 ton truck.
cling
How do you ride this bike? That makes a big difference for what you'll want/need.
It would not be hard to get it to 120 square at 98" on the high hot rod side. All the elements suggested already. Dynas have a problem with a decent selection of pipes and hitting the high numbers will be very pipe dependent. With a larger carb, headwork, heads milled some it would be possible to hit about 105 square, same cam.
Quote from: 71R/T on September 21, 2021, 08:20:03 AM
I have a 2003 Dyna FXD, put in a 98" Big Bore kit 2 years ago. 9.8:1 CR, stock heads Andrews 31 cams. It has 2-1 VH Pro-Pipe, High Flow AC, Carb re-jetted, upgraded ignition module, timing is set at 32 degrees. HP is ~90, TQ is 100ft/lbs. I want more without going to 124 but I will if I have to. Would different heads/cams or headwork give me that much more to be worth it or should I just go to 124". This bike is ridden solo only. Thanks.
Real curious how timing is set to 32 degrees on a carburated twin cam engine. Please explain.
Here's a recent example in the dyno forum. Good numbers, from good heads, good parts mix and a great tune by Joe.
FYI, this one is FI.
https://harleytechtalk.com/htt/index.php/topic,113883.msg1364322.html#msg1364322 (https://harleytechtalk.com/htt/index.php/topic,113883.msg1364322.html#msg1364322)
Quote from: turboprop on September 21, 2021, 10:03:21 AM
Quote from: 71R/T on September 21, 2021, 08:20:03 AM
I have a 2003 Dyna FXD, put in a 98" Big Bore kit 2 years ago. 9.8:1 CR, stock heads Andrews 31 cams. It has 2-1 VH Pro-Pipe, High Flow AC, Carb re-jetted, upgraded ignition module, timing is set at 32 degrees. HP is ~90, TQ is 100ft/lbs. I want more without going to 124 but I will if I have to. Would different heads/cams or headwork give me that much more to be worth it or should I just go to 124". This bike is ridden solo only. Thanks.
Real curious how timing is set to 32 degrees on a carburated twin cam engine. Please explain.
It has a programmable ignition module.
Thanks everyone for the replies!!!!
Quote from: 71R/T on September 21, 2021, 10:09:29 AM
Quote from: turboprop on September 21, 2021, 10:03:21 AM
Quote from: 71R/T on September 21, 2021, 08:20:03 AM
I have a 2003 Dyna FXD, put in a 98" Big Bore kit 2 years ago. 9.8:1 CR, stock heads Andrews 31 cams. It has 2-1 VH Pro-Pipe, High Flow AC, Carb re-jetted, upgraded ignition module, timing is set at 32 degrees. HP is ~90, TQ is 100ft/lbs. I want more without going to 124 but I will if I have to. Would different heads/cams or headwork give me that much more to be worth it or should I just go to 124". This bike is ridden solo only. Thanks.
Real curious how timing is set to 32 degrees on a carburated twin cam engine. Please explain.
It has a programmable ignition module.
Sure, I get that. Ignition modules for carburated TC engines have ignition maps the are three dimensional, with over a hundred cells with timing values and they do not have timing marks on their flywheels or even a way to see the flywheels. You dont know what you are talking about.
Quote from: turboprop on September 21, 2021, 11:27:36 AM
Quote from: 71R/T on September 21, 2021, 10:09:29 AM
Quote from: turboprop on September 21, 2021, 10:03:21 AM
Quote from: 71R/T on September 21, 2021, 08:20:03 AM
I have a 2003 Dyna FXD, put in a 98" Big Bore kit 2 years ago. 9.8:1 CR, stock heads Andrews 31 cams. It has 2-1 VH Pro-Pipe, High Flow AC, Carb re-jetted, upgraded ignition module, timing is set at 32 degrees. HP is ~90, TQ is 100ft/lbs. I want more without going to 124 but I will if I have to. Would different heads/cams or headwork give me that much more to be worth it or should I just go to 124". This bike is ridden solo only. Thanks.
Real curious how timing is set to 32 degrees on a carburated twin cam engine. Please explain.
It has a programmable ignition module.
Sure, I get that. Ignition modules for carburated TC engines have ignition maps the are three dimensional, with over a hundred cells with timing values and they do not have timing marks on their flywheels or even a way to see the flywheels. You dont know what you are talking about.
When I said "Timing is set at 32 degrees" I was referring to the map setting in the ignition module. I have built car engines for years and I understand how to set timing. Maybe you should just keep negative comments to yourself. I don't understand the need to insult me.
Here is a 98 with our pro heads dynoed after many miles on it. https://harleytechtalk.com/htt/index.php/topic,97306.msg1286027.html#msg1286027
Quote from: 71R/T on September 21, 2021, 12:21:53 PM
Quote from: turboprop on September 21, 2021, 11:27:36 AM
Quote from: 71R/T on September 21, 2021, 10:09:29 AM
Quote from: turboprop on September 21, 2021, 10:03:21 AM
Quote from: 71R/T on September 21, 2021, 08:20:03 AM
I have a 2003 Dyna FXD, put in a 98" Big Bore kit 2 years ago. 9.8:1 CR, stock heads Andrews 31 cams. It has 2-1 VH Pro-Pipe, High Flow AC, Carb re-jetted, upgraded ignition module, timing is set at 32 degrees. HP is ~90, TQ is 100ft/lbs. I want more without going to 124 but I will if I have to. Would different heads/cams or headwork give me that much more to be worth it or should I just go to 124". This bike is ridden solo only. Thanks.
Real curious how timing is set to 32 degrees on a carburated twin cam engine. Please explain.
It has a programmable ignition module.
Sure, I get that. Ignition modules for carburated TC engines have ignition maps the are three dimensional, with over a hundred cells with timing values and they do not have timing marks on their flywheels or even a way to see the flywheels. You dont know what you are talking about.
When I said "Timing is set at 32 degrees" I was referring to the map setting in the ignition module. I have built car engines for years and I understand how to set timing. Maybe you should just keep negative comments to yourself. I don't understand the need to insult me.
Map setting in the module? Funny. You really do not know, but that is alright. You aren't the first. Best of luck with your project.