Aside from Doc and 240, I only know of one other set of the modified plenums..... mine...

I am very happy with them and they do add power... the surprising thing to me was that my max boost with the stock plenums was hitting 21-22PSI... after I got the modded plenums I was hitting 18-19PSI with better track performance....

I cant give you numbers because I didnt do a before and after with just the plenum change.... I did a write up back when I got them...have to search for it..

I would guess the reason you dont here much talk about these is that there are only a few sets out there (that I know of).. when 240 offered to do these, nobody wanted to get them. I have been running mine for almost 2 years and didnt know until a few weeks ago that Rob was selling them now.... wish he was doing them when I got mine....


edit: Here is the link.... and it does have hp/trq numbers

https://www.crossfireforum.org/forum...manifolds.html