After months of testing we’re ready to announce our CNC head program. We’ve tested 4 different variations of porting and valve jobs to get the best performing combination available.
Flow bench number don’t always tell the whole story. We went one step further and correlated flow numbers to actual dyno data. Many vendors claim their head flows 250, 260, or 270 cfm, what does that really mean?
What most vendors claim their peak flow at max lift. So a head may flow 270 CFM at .500 lift. How about flow at lower lifts? To even take advantage of the flow at high lift you need to have a camshaft that has that high of a lift in the first place. The flow at low, mid and high lift have to balanced a certain way to net the most effective power curve. Most of this is done through different valve jobs, what works on one particular head may not work on another. We have worked with a head porter and developed a CNC program that not only brings consistent quality and performance, but also makes the most power of any head that we’ve tested, ours and the competitions
Here are some of the basic specs on the head:
.050″ 61 CFM
.100″ 107 CFM
.150″ 151 CFM
.200″ 189 CFM
.250″ 222 CFM
.300″ 244 CFM
.350″ 258 CFM
.400″ 269 CFM
.450″ 274 CFM
.500″ 277 CFM
.050″ 44 CFM
.100″ 88 CFM
.150″ 134 CFM
.200″ 193 CFM
.250″ 229 CFM
.300″ 245 CFM
.350″ 249 CFM
.400″ 255 CFM
.450″ 261 CFM
.500″ 265 CFM
Why do we do flow every .050″? Because low lift flow is important and so is good data resolution.
Intake Valve: S.S. +1mm oversize
Exhaust Valve: Inconel +1mm oversize
Valveguides: Manganese bronze
Valve springs: Dual valve springs with titanium retainers, good for 10,000 rpm and high lift camshafts
Hand finishing of runner, blending of bowl area, and chambers.
Now for the results and eye candy. We’ll have more pics & even video of the CNC process coming up soon.
This was tested on my car with Tomei 280 cams, AMS VSR intake manifold, stock TB, AMS FMIC, full 3″ exhaust. AMS GT35R turbo kit, 2.0L 9:1 compression. Timing was conservative for testing purposes.
24psi = 557whp!!!
This graph shows the three heads that we were working on and the development of power after each improvement!
AMS CNC EVO 8 Head – New head, no core needed – $3995.00
AMS CNC EVO 9 Head – New head, no core needed – $4095.00
AMS CNC EVO 8 Head – With Core – $2595
AMS CNC EVO 9 Head – With Core – $2695
Core heads are stripped, cleaned, new guides, seals, ect.