At first was going explain how porting and polishing worked. But instead, I'm going to list what can kinda results you except when you port your intake manifold on DOHC Neons and cylinder head on both the SOHC and DOHC. The intake manifold on the SOHC engine cannot be ported due to it being made of glass-filled plastic. Port matching the intake can help other mods like cold air induction and bored throttle bodies product more hp and torque. I'm unable to show your pictures of Shane Hale's Intake and TB because the roll of filmed used to take pictures with failed to produce any pictures. Both parts were modified by GUDE Performance in Canyon Lake, CA. Shane started his Neon after re-installing these parts, he took reved the engine and noticed how it had more throttle response, than before. GUDE has told me before work was performed on Shane's parts that we could except about a 12-15hp gain over manifold and throttle body stock. Well, Shane did a short test on his G-Tech meter. His best time before the install was 15.9 in the 1/4. His best time at Carlsbad was 16.0. So it's pretty close. After he mentioned, while "not trying very hard.." got an instant improvement for 3 tenths! His time on the G-tech dropped from 15.9 to 15.6. So for those that doubt GUDE Workmanship, the results speak for themselves. Shane has since been to the track three times with his newly modified parts from GUDE. His best ET so far is 15.7@87. With more practice, he should be going faster soon. Below are his results from Dyno Day.
Owen just had his DOHC intake manifold Extrude Hone from Pacific Neon Performance. I don't have a graph yet, but his overall air flow before the process was 810cfm. All the cylinders had different flow measurements, with an avg of 201cfm per runner. After the process, which included polishing the plenum by hand the runners were more even all were with in 2-3cfm of each other. Now the avg cfm for each runner was now 253cfm for a total cfm of 1013cfm, which is 210cfm more than before. We feel this gain in total air flow is worth about 12-20hp at the wheels without any other mods on a stock DOHC engine. We hope to have dynojet testing and pictures soon.
Owen's DOHC ACR is stock, except of the K&N drop-in filter. Just look at Shane's gains just from a Dynomax exhaust, custom intake and GUDE parts. You can clearly see the gains on Shane's car. It's an worth while improvement for your Neon.
