Dave Mackie 630 or TMan 680PS2

[Tq Monster]

I'm in the process of gathering a set of cams for a 124 twincam  build I have going together and im stuck or better yet would like to know which cam would perform better at 12:1 compression I've spoke with Mr.Mackie as well as TR but I'd like to ask the guys here who's possibly built this engine before! I'm looking for torque right off ie this is going in afully dressed bagger also would the 662-2  be a possible contender with that mu h squeeze? Thanks for any help

[Ohio HD]

I haven't used either, but there are a few examples of the 662-2 in the dyno section of the site. There's one T-man 680 I found. You'll note that all of these examples are less than 12:1 compression. That's pushing the envelope for the cams you mentioned in a touring rig.

Below are links to a few 662-2 dyno sheets, and the one T-man 680. Also are a couple of Cycle Rama 630i cams in the list. I'd consider dropping the compression if you can. If not, maybe look at the S&S 640 cams. They work well at 12:1.

2009, 124", FLTR, Tman kit, 680, HPI 58mm, Burns 2-1

2007, 124", FLHX, Mega-Flo S&S heads, 662-2 cams

2000, 124", FLTRSE, 662-2 cams, Hillside heads

2008, 124", FLHX, CR630i, Burns pipe, wfolarry 110 heads

2010, 124", FLHTK, CR630i, Mega-Flo 110 Heads, HPI 55/58, 6.2 Inj, Dragula 2

[Ohio HD]

I'll also add I assume you're running fuel injection, a late model bike? If carbureted, that adds a level of complexity to getting a large motor tuned well with high compression.

[FLDavetrain]

630 Mackie I've used few times but capped it at 11.5:1 at 124 & 131". Nice square power in 124" but agree 12:1 would be pushing it

[Hossamania]

How is the bike to be ridden?

[Tq Monster]

It's going in a 2016 road glide that'll be a around town hotrod with the occasional trip to the Bay area or Vegas I'm tossing around the idea of using a PV and running E85... when I spoke to TR he mentioned that 220ccp  would be the least he'd run that cam

[Tq Monster]

I haven't used either, but there are a few examples of the 662-2 in the dyno section of the site. There's one T-man 680 I found. You'll note that all of these examples are less than 12:1 compression. That's pushing the envelope for the cams you mentioned in a touring rig.

Below are links to a few 662-2 dyno sheets, and the one T-man 680. Also are a couple of Cycle Rama 630i cams in the list. I'd consider dropping the compression if you can. If not, maybe look at the S&S 640 cams. They work well at 12:1.

2009, 124", FLTR, Tman kit, 680, HPI 58mm, Burns 2-1

2007, 124", FLHX, Mega-Flo S&S heads, 662-2 cams

2000, 124", FLTRSE, 662-2 cams, Hillside heads

2008, 124", FLHX, CR630i, Burns pipe, wfolarry 110 heads

2010, 124", FLHTK, CR630i, Mega-Flo 110 Heads, HPI 55/58, 6.2 Inj, Dragula 2

I have T Man 20* angle pistons and I really didn't want to alter them to lower compression all those dyno's look great it'll be awesome if I could see an 124 with a zilla running the 680 ps2 I've looked it doesn't exist

[Tq Monster]

How is the bike to be ridden?

Hard at times civil at others

[Tq Monster]

630 Mackie I've used few times but capped it at 11.5:1 at 124 & 131". Nice square power in 124" but agree 12:1 would be pushing it

where did it start making power? And did you make more than 145 square

[Ohio HD]

It's going in a 2016 road glide that'll be a around town hotrod with the occasional trip to the Bay area or Vegas I'm tossing around the idea of using a PV and running E85... when I spoke to TR he mentioned that 220ccp  would be the least he'd run that cam

I'm sure if TR said you can run the 680PS2 at 12:1, I would trust him. It may even make some good lower power, but will be really hard on the motor if you lug it at lower RPM's. Other than that, I'd follow his plan. He's been around the block a few times.

[Tq Monster]

It's going in a 2016 road glide that'll be a around town hotrod with the occasional trip to the Bay area or Vegas I'm tossing around the idea of using a PV and running E85... when I spoke to TR he mentioned that 220ccp  would be the least he'd run that cam

I'm sure if TR said you can run the 680PS2 at 12:1, I would trust him. It may even make some good lower power, but will be really hard on the motor if you lug it at lower RPM's. Other than that, I'd follow his plan. He's been around the block a few times.

my thoughts exactly I was just curious as to what anyone else has seen or done with these cams at 12:1cr Thanks for your time

[Tireman]

Neither of the 2 choices you mentioned but the SS640 likes compression

https://harleytechtalk.com/htt/index.php/topic,90369.msg1038681.html#msg1038681

[Tq Monster]

Neither of the 2 choices you mentioned but the SS640 likes compression

https://harleytechtalk.com/htt/index.php/topic,90369.msg1038681.html#msg1038681

Can't argue with that! That's a runner

[itsafatboy]

Woods TW9FG would be a great option just saying

[Ohio HD]

Woods TW9FG would be a great option just saying

10.5 corrected compression on a Twin Cam street motor?    I don't think so.

[turboprop]

I'm in the process of gathering a set of cams for a 124 twincam  build I have going together and im stuck or better yet would like to know which cam would perform better at 12:1 compression I've spoke with Mr.Mackie as well as TR but I'd like to ask the guys here who's possibly built this engine before! I'm looking for torque right off ie this is going in afully dressed bagger also would the 662-2  be a possible contender with that mu h squeeze? Thanks for any help

'Torque right off idle', 'at 12:1 compression'.  The two are not mutually supporting. 12:1 in a bagger? What is the intended use of this bike with torque right off idle?

[Tq Monster]

I'm in the process of gathering a set of cams for a 124 twincam  build I have going together and im stuck or better yet would like to know which cam would perform better at 12:1 compression I've spoke with Mr.Mackie as well as TR but I'd like to ask the guys here who's possibly built this engine before! I'm looking for torque right off ie this is going in afully dressed bagger also would the 662-2  be a possible contender with that mu h squeeze? Thanks for any help

'Torque right off idle', 'at 12:1 compression'.  The two are not mutually supporting. 12:1 in a bagger? What is the intended use of this bike with torque right off idle?

i ride an Road Glide Ultra and myself and the wife aren't a small couple to be honest! We ride around town but also do club runs and we need the passing power  and to keep up with those M8's

[turboprop]

I'm in the process of gathering a set of cams for a 124 twincam  build I have going together and im stuck or better yet would like to know which cam would perform better at 12:1 compression I've spoke with Mr.Mackie as well as TR but I'd like to ask the guys here who's possibly built this engine before! I'm looking for torque right off ie this is going in afully dressed bagger also would the 662-2  be a possible contender with that mu h squeeze? Thanks for any help

'Torque right off idle', 'at 12:1 compression'.  The two are not mutually supporting. 12:1 in a bagger? What is the intended use of this bike with torque right off idle?

i ride an Road Glide Ultra and myself and the wife aren't a small couple to be honest! We ride around town but also do club runs and we need the passing power  and to keep up with those M8's

12:1 is totally inappropriate for your application. I would think with a online name of Tq Monster that you would have an understanding of this. 12:1 with pump gas on a heavy bagger will require a very late intake close to prevent itself from detonation. The late intake close will prevent any torque from happening right off idle, and even in the early/mid range of the rpm band. 12:1 is for racing, with pump gas in lighter bikes with different gearing, the exact opposite of what you have. Best of luck with your project.

[Tq Monster]

 
[/quote]

I'm in the process of gathering a set of cams for a 124 twincam  build I have going together and im stuck or better yet would like to know which cam would perform better at 12:1 compression I've spoke with Mr.Mackie as well as TR but I'd like to ask the guys here who's possibly built this engine before! I'm looking for torque right off ie this is going in afully dressed bagger also would the 662-2  be a possible contender with that mu h squeeze? Thanks for any help

'Torque right off idle', 'at 12:1 compression'.  The two are not mutually supporting. 12:1 in a bagger? What is the intended use of this bike with torque right off idle?

i ride an Road Glide Ultra and myself and the wife aren't a small couple to be honest! We ride around town but also do club runs and we need the passing power  and to keep up with those M8's

12:1 is totally inappropriate for your application. I would think with a online name of Tq Monster that you would have an understanding of this. 12:1 with pump gas on a heavy bagger will require a very late intake close to prevent itself from detonation. The late intake close will prevent any torque from happening right off idle, and even in the early/mid range of the rpm band. 12:1 is for racing, with pump gas in lighter bikes with different gearing, the exact opposite of what you have. Best of luck with your project.

we shall see how things turn out the project is in full swing ill return with sae dyno sheets with my findings good or bad this is going in my bagger

[m1marty]

Did a 117 for one of my guys using the Mackie 630. 03 Dyna, 6spd with a steep chain drive. He's around 190.
Comp was set at 11.5 and that is getting to be on the edge. No way would I run that at 12:1 on pump gas and certainly not in a bagger loaded 2up

[FLDavetrain]

Did a 117 for one of my guys using the Mackie 630. 03 Dyna, 6spd with a steep chain drive. He's around 190.
Comp was set at 11.5 and that is getting to be on the edge. No way would I run that at 12:1 on pump gas and certainly not in a bagger loaded 2up

Agree. Ran Mackie 2 times at 11.5 and that was pushing it on short ride baggers and 210 Lb rider. 500cca batteries last under 2 yrs here at that compression. Lots more headaches at 12:1 loaded up w 2 big people and touring. Should be avoided completely

[Tq Monster]

Just spoke with Mackie in regards to the 12:1 cr he mentioned it can be done but it'll be minimal gain he recommended going down to 11:5 cr if I intended on using his 630L cam

[hrdtail78]

The tman 680 @ 12:1 Ohio linked is a whole kit and set up by Tman.  He actually sends two different base gaskets to make sure zero deck is reached.

I have a another 124 @ 12:1 w/ his 680 going on dyno tomorrow.  Better street able 2:1 on it, because I don't think the Burns is best for showing what this cam can do lower end.

[Ohio HD]

The tman 680 @ 12:1 Ohio linked is a whole kit and set up by Tman.  He actually sends two different base gaskets to make sure zero deck is reached.

I have a another 124 @ 12:1 w/ his 680 going on dyno tomorrow.  Better street able 2:1 on it, because I don't think the Burns is best for showing what this cam can do lower end.

I look forward to seeing that one too. 

I agree, a straight up Burns is to get upper end power.

[Tq Monster]

The tman 680 @ 12:1 Ohio linked is a whole kit and set up by Tman.  He actually sends two different base gaskets to make sure zero deck is reached.

I have a another 124 @ 12:1 w/ his 680 going on dyno tomorrow.  Better street able 2:1 on it, because I don't think the Burns is best for showing what this cam can do lower end.

Great I'd like to see that one as well

[kd]

The TMan 680 always seems to make good power bottom to top.  If set up the way TR says to do it, it'll probably rock. For some reason that extra .020 lift seems to really get it working.

[hrdtail78]

Having a clutch issue.  Waiting on parts and I will address this and put final up in Dyno section.

124 12:1
680
D&D Borezilla
1.442 primary ratio, and in my opinion is not helping clutch.

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[Ohio HD]

Jason, you think rather than lower the gearing in the primary, it's better to lower it after the clutch? I guess I can see where that can effect the clutch holding, getting more leverage in front of it.

[hrdtail78]

For a street bike?  I have had good luck with a 30 or 31 MDP.  I think it gives it enough to satisfy most.  That same tq of a lower ratio is also the lower ratio that is driving your engine during engine braking.  BUT I don't know if it's better.

Purpose built bikes.  Start with speed/ rpm needed to get the ET, and reverse engineer from there.