1AWD90
15+ Year Contributor
- 134
- 0
- Sep 6, 2007
-
Marshall,
Minnesota
I just finished my port and polish on my 1g head. Also added half milimeter over sized stainless steal valves that are polished with swirl cut. To finish it off I did a 3 angle valve job. I had an average gain of 18.5 cfm on the intake and 39.5 cfm gain on the exhaust 
. Ill uses .400" lift for an example. I started out at 267.4 cfm on intake and 232.7 cfm on exhaust that gave me a relationship of 87%. After I was done my numbers were 283.8 cfm on intake and 260.7 cfm on exhaust. This gave me a relatioship of 92%. I found that the stock head flowed horrible at .100" lift and had a poor relationship of only 62%. I focused mostly on the exhaust because the head will be going on a turbo car. Ill try to post some pictures tommrow. Let me know what you guys think of the gains.
. Ill uses .400" lift for an example. I started out at 267.4 cfm on intake and 232.7 cfm on exhaust that gave me a relationship of 87%. After I was done my numbers were 283.8 cfm on intake and 260.7 cfm on exhaust. This gave me a relatioship of 92%. I found that the stock head flowed horrible at .100" lift and had a poor relationship of only 62%. I focused mostly on the exhaust because the head will be going on a turbo car. Ill try to post some pictures tommrow. Let me know what you guys think of the gains.
