You've got me curious. I'm currently Stg1 with decatted stock HP, upgrading to a 124 kit. I've got the 4" TAB's with zombie baffles, but went with the smaller Thunder Torque Inserts #158, inside the zombie baffles, to recapture any lost torque. I would really like to hear a video, even if it doesn't do it justice.

 

The 158 TTI is more for 2" (and larger) mufflers, and too small for your Zombies. The TTI should be the same diameter or larger than than the baffle hole. The 258 TTI will be the correct size for yours whether the baffle is in or removed. If you missed it, way at the bottom of the page there is a link to choosing the correct size.
http://www.dkcustomproducts.com/choo...ti-fit-faq.htm

You can always give DK a call as they're more than willing to help. But for only $18.95, you could always just order up the 258s. They're so simple and quick to change out, you could try both sizes to compare the sound, torque and how the engine runs. This would be better for you than listening to a video that I don't have (sorry). My money says you'll stay with the 258s.

Enjoy yor Tabs.
Steve

 

I actually did call DK when ordering and the 158 is specifically what they recommended. Even said to turn them sideways for minimal restriction. You're right though, easy and cheap to experiment. Probably would need a dyno to determine the torque difference

 

That's contrary to the information posted on their website, but I'm sure they would have their reasons considering your build and what you're after. DK knows their stuff.
Anyhoooo,,, your experiment will definitely determine which TTI configuration makes your ears and butt dyno happy.the 258 with baffle removed did it for me). Just a tip from my experience... When comparing the differences (158, 258, baffle in, baffle out etc), ride it for at least a couple of days before changing it up to a different configuration, and don't hesitate to do any a second time. Also, just for interest's sake after you've made your choice,,, if you have a buddy that you trust with your ride, have him do a couple of ride pasts while you stand on the side of the road.

Good luck, have fun and enjoy your ride..

 

Sweet mother of god!!! I don’t think I’ve ever been so excited twisting the throttle on anything like that, and I wasn’t even moving! A+ to tab performance. Now if it stops raining I can get out and give her a tru butt dyno test.

 

I'm glad that you're so thrilled with your choice. I kind of figured that you would be.

 

sweetglidez - Did you get to road test them yet? What do you think?

 

Yeah, I just rode an extended ride for the first time yesterday with my Zombies, they gave me a chubby

 

Just bought both sizes. What did you end up doing and how do you like it? Curious if I am going to like this with the zombies or removed and with the 258.

 

Haven't had a chance to change from my initial setup as described. Been busy doing other mods