Throttle blade angle on 2.8 throttle body (Page 1/1) 1985 Fiero GT MAR 16, 01:17 PM So, I noticed on my throttle body that full throttle doesn't put the throttle blade at an exact 90*, keeps it slightly angled, is there a reason for this? There is a stop that protrudes and stops it at wide open throttle before 90*, just curious why. I would assume a perfect 90* would be the best for airflow. Patrick MAR 16, 03:59 PM quote Originally posted by 1985 Fiero GT: I would assume a perfect 90* would be the best for airflow. You'd be wrong then. If you google it, you'll discover it has to do with turbulence. An example of these many online discussions is Here. 1985 Fiero GT MAR 16, 04:17 PM Interesting, that makes sense pmbrunelle MAR 17, 05:23 PM From some online searches I did (since I saw this topic), in some cars where the throttle body is part of a curvy path, having the throttle plate angled may help guide the air where it needs to go. ******************************************************************************** I don't know if we can determine the optimum throttle angle for the Fiero V6 without flow testing. ******************************************************************************** From this article: https://www.mdpi.com/2227-9717/11/7/1897 This graph shows how the flow of a throttle changes with throttle angle: There is not much gain from 80° to 90°. A throttle like this could feel non-linear to the driver, where the last 10° of travel doesn't change the engine output very much (as in, a dead spot). So, with a cable throttle, you may wish to limit the travel to have a more linear-feeling throttle. Of course, with drive-by-wire, you can hide this behaviour from the driver, as throttle plate position is independent of accelerator pedal position. ******************************************************************************** On the White Bug, I took a guess and I grinded the throttle stop so that the throttle plate could rotate to 90°. From the seat of the pants the engine feels okay I guess Of course, the engine is turbo, so throttle linearity went out the window anyway... ******************************************************************************** I don't have a very strong opinion on the topic.