Subject: Re: H89 vs gx head by D on 2019/5/18 2:04:53
He had it stock then had the H89 worked on but said he got no big improvement overall to stock. There could be a limit for boost with wedge design and probably an e15et hemi heads would be more rewarding when it comes to 2 valves per chamber. Wedge is very healthy for NA though probably even more so if they are welded up and reshaped to late chev design like TK used for an L series. Also many makes prefer square inlet ports over rounded in many applications. We would prob never see an cnc a series head with these features though but would be interesting if some kid or oldboy in the future makes a billet version :) However plenty of 16v heads fit the A series as well. https://www.onallcylinders.com/wp-cont ... 1/tfs-51410002-m58_xl.jpg https://www.onallcylinders.com/wp-cont ... 2016/01/Presentation1.jpg
