This link is no longer good but it is an engineering forum..
http://ctma.ncms.org/NewProjectIdeas/IncreasingHorsepower.htmThe qoute I copied years ago from the link..
SVTC intake "better than a 20% increase in airflow with less than 2% runner to runner variability"....
Now, I called Extrude Hone (not sure who I talked with) years ago and posted this in the past..
"Awhile back I got some approx CFU rates from Extrude Hone..
stock = 155 CFU
single= 170 CFU
double= 180 CFU
triple= 188-190 CFU"
Based on the above discussion, I reviewed the notes I took..which were as follows..
Baseline SE "150-160" CFU (so I said 155)
Final product was "175-180"...I assumed this to mean DH.
Gain per pass "8-10" CFU. I did NOT then specifically ask about SH vs DH so I extrapolated to give people an idea..(ie subtracted 10 from the DH to give 170 for the single Hone. And added the 8-10 to get the estimated 188-190 with a TH). So my extrapolations may have been inaccurate if SVTJeff is correct.
On the other hand...a 20% increase as suggested by the engineering forum (it was an interesting link but I cannot recover it) over stock of 150 would be 180, not the 170 SVTjeff suggests..so something is not adding up. Be it single or dual honed, it would be nice to flow a stock SVT UIM
