Tuning 120 with S&S 625 cams

[KiwiRob]

I have been tuning my 120 with S&S 625 cams & I tried two different exhaust systems.  Firstly, I used a V&H Pro Pipe Chrome 2-1, which tuned easily but was sluggish @ WOT. They were also a bit loud for my liking, so pulled them & fitted the stock Soft Tail head pipes with Khrome Werks slip-ons.
Man what a difference they made to the WOT, with plenty of get-up & go. Tuning with the 2-2 pipes was a drag though, but I got it done.
I wonder if this is a classic example of over-exhausting with the S&S cams Pro-Pipe combo.
I should also mention that his was with the TTS MT8 custom map from TTS via an Aussie forum member.
With the new MT9 files, FPJ176 calibration, tuning with the 2-2 combo was a bit of a drag again with VTune3 also wanting to increase the engine displacement in tuning constants till it topped out @ 159.5cid (maximum). The VEs, by the way, only topped out in the rear cylinder above 2250 rpm @ 0 TPS.
So I re-installed the 2-1 Pro-Pipes, with a more baffling to try & quieten it down some. Tuning with FNL176 calibration was much quicker/easier with these pipes, with the VEs behaving themselves, but WOT is still sluggish with these pipes.
The options I have are to go back to the stock pipe slip-on combo & try tuning while staying out of or ignoring the problem RPM area, or try to figure out how to make the Pro-Pipes work with a mechanical fix &/or tuning.
I would like to keep the 2-1 pipes but I have no problem re-installing the stock pipes & slip-ons.
Any ideas, besides changing the cams, would be really appreciated thanks - Rob

'07 Soft Tail Deluxe
120cid + 0.010 flat tops
110 heads
87cc & 11.2:1 CR
S&S 625
TTS

[strokerjlk]

I have been tuning my 120 with S&S 625 cams & I tried two different exhaust systems.  Firstly, I used a V&H Pro Pipe Chrome 2-1, which tuned easily but was sluggish @ WOT. They were also a bit loud for my liking, so pulled them & fitted the stock Soft Tail head pipes with Khrome Werks slip-ons.
Man what a difference they made to the WOT, with plenty of get-up & bo.go. Tuning with the 2-2 pipes was a drag though, but I got it done.
I wonder if this is a classic example of over-exhausting with the S&S cams Pro-Pipe com..NO
I should also mention that his was with the TTS MT8 custom map from TTS via an Aussie forum member. maps from other builds seldom match another combo
With the new MT9 files, FPJ176 calibration, tuning with the 2-2 combo was a bit of a drag again with VTune3 also wanting to increase the engine displacement in tuning constants till it topped out @ 159.5cid (maximum). The VEs, by the way, only topped out in the rear cylinder above 2250 rpm @ 0 TPS. you could disregard that as it is decel .look at idle and max tq ve's to evaluate what your CI constant should be.
So I re-installed the 2-1 Pro-Pipes, with a more baffling to try & quieten it down some. Tuning with FNL176 calibration was much quicker/easier with these pipes, with the VEs behaving themselves, but WOT is still sluggish with these pipes. shouldn't be ,its a matter of tuning
The options I have are to go back to the stock pipe slip-on combo & try tuning while staying out of or ignoring the problem RPM area, or try to figure out how to make the Pro-Pipes work with a mechanical fix &/or tuning. again its tuning
I would like to keep the 2-1 pipes but I have no problem re-installing the stock pipes & slip-ons.
Any ideas, besides changing the cams, would be really appreciated thanks - Rob keep with it .its a matter of tuning.

'07 Soft Tail Deluxe
120cid + 0.010 flat tops
110 heads
87cc & 11.2:1 CR
S&S 625
TTS

[joe_lyons]

Is the baffle plug still in the baffle?

[KiwiRob]

Thanks Jim, I was hoping that it would be the tune with the Pro-Pipes. Just need to get my head around which tables to tinker with to get the same get up & go that I get with the 2-2 pipe/slip-on system.
If I get pissed off with the Pro-Pipes, 'cause they are still a bit loud even after adding & altering the baffles, I'll go back to the 2-2 pipe/slip-on set up, which sounded better anyway.
Joe, I've moved the baffle plug half way into the baffle & added more baffling at the collector end & and another baffle to the exit end. Replaced all the packing + the extra baffling has helped with the sound, but still a little loud I feel. Maybe I'm getting a bit fussy in my senior years. - Rob

[strokerjlk]

With you adding baffle and wrap . The 2-2 probably does pull more power .

[KiwiRob]

The Pro-Pipes were sluggish when I first installed them earlier this year, even with the stock baffling. With baffles altered, the WOT is still no where like the 2-2 pipes. I'll play with the AE table & see what Vtune3 wants to do with the timing. Thanks by the way. - Rob

[strokerjlk]

The Pro-Pipes were sluggish when I first installed them earlier this year, even with the stock baffling. With baffles altered, the WOT is still no where like the 2-2 pipes. I'll play with the AE table & see what Vtune3 wants to do with the timing. Thanks by the way. - Rob

That plug kills em . Not to bad on a small ci motor. But it really kills a 120 .hard to even make 1 hp per ci.

[KiwiRob]

Thanks Jim. Pro-Pipes are too noisy with stock baffles for me, so looks like the 2-2 pipes are going back on. Thanks again. - Rob