Originally Posted by 71
Sounds like they work for you. Are those chambered or straight through? Also what kind of sound reduction do they give you? Also have you dyno'd with open headers in comparison?
They are chambered.
http://www.summitracing.com/parts/FL...0/?image=large
Huge sound reduction over straight pipe on my old blown 462.
462 8-71 With Mufflers:
http://www.youtube.com/watch?v=i5v3Xu67QlY
462 8-71 Straight Pipe:
http://www.youtube.com/watch?v=uPxqHQOJ3Xw
With or without mufflers, it ran 9.60s at 12 PSI at 3700 lbs. That was with a .648/.669 solid tappet cam and GM049 Oval Port Heads. This was 2 yrs before I had the chassis done. Motor was probably in the 1050-1100 HP range.
I should also mention that those were the 3-chamber 3.5" mufflers in the videos.
My 505 and 568 blower motors both used the 4.5" Top 10s as in the photo above.
No, I've not dyno'd it on an engine or rear wheel dyno with/without mufflers. The drag strip is the best comparison, in which case I saw no difference.