Is anyone still enlarging the diameter of our throttle bodies, Wouldn't it be nice to add a bit of power with a little more air?? Options

[second wind]

Happy Thanksgiving everyone....so I have seen this before but have never heard about the results.....is the idea any good? How do we get it done on our cars? Just thinking out loud....thank you (IMG:style_emoticons/default/smile.gif)
gg

[Geezer914]

Look on the Samba for a 2.1L Vanagon throttle body. They are 50mm vs 45. You have to modify the throttle shaft on your existing throttle body to fit the larger throttle plate in order to keep the TPS. I enlarged the plenum to 50 mm with a tail pipe expander and ordered a new gasket for a Vanagon. My engine is a 2056 using 1.8L plenum, runners, and Let fuel injection.

[BeatNavy]

Look on the Samba for a 2.1L Vanagon throttle body. They are 50mm vs 45. You have to modify the throttle shaft on your existing throttle body to fit the larger throttle plate in order to keep the TPS. I enlarged the plenum to 50 mm with a tail pipe expander and ordered a new gasket for a Vanagon

I've seen this mentioned in threads before, primarily for the 1.8L plenum. Does anyone know of a good thread demonstrating how to do this on a 2.0? I'd love to open up air flow a bit for my 2270, not just for WOT but for getting more air at cold starts.

[Montreal914]

Look on the Samba for a 2.1L Vanagon throttle body. They are 50mm vs 45. You have to modify the throttle shaft on your existing throttle body to fit the larger throttle plate in order to keep the TPS. I enlarged the plenum to 50 mm with a tail pipe expander and ordered a new gasket for a Vanagon

I've seen this mentioned in threads before, primarily for the 1.8L plenum. Does anyone know of a good thread demonstrating how to do this on a 2.0? I'd love to open up air flow a bit for my 2270, not just for WOT but for getting more air at cold starts.

@BeatNavy Rob, I tend to find more information on Shoptalkforums on this topic.

Here's a thread looking at plenum efficiency and Vanagon TB. Seems appropriate for your 2270. (IMG:style_emoticons/default/smile.gif) But do some search there as there is a lot more information. Pyledriver seems pretty knowledgeable.

https://shoptalkforums.com/viewtopic.php?t=102542

Definitely following closely all of your engine work/optimization. (IMG:style_emoticons/default/stirthepot.gif) (IMG:style_emoticons/default/smile.gif)

[BeatNavy]

Look on the Samba for a 2.1L Vanagon throttle body. They are 50mm vs 45. You have to modify the throttle shaft on your existing throttle body to fit the larger throttle plate in order to keep the TPS. I enlarged the plenum to 50 mm with a tail pipe expander and ordered a new gasket for a Vanagon

I've seen this mentioned in threads before, primarily for the 1.8L plenum. Does anyone know of a good thread demonstrating how to do this on a 2.0? I'd love to open up air flow a bit for my 2270, not just for WOT but for getting more air at cold starts.

@BeatNavy Rob, I tend to find more information on Shoptalkforums on this topic.

Here's a thread looking at plenum efficiency and Vanagon TB. Seems appropriate for your 2270. (IMG:style_emoticons/default/smile.gif) But do some search there as there is a lot more information. Pyledriver seems pretty knowledgeable.

https://shoptalkforums.com/viewtopic.php?t=102542

Definitely following closely all of your engine work/optimization. (IMG:style_emoticons/default/stirthepot.gif) (IMG:style_emoticons/default/smile.gif)

Thanks Montreal914 ! That's a very interesting thread, although wow do they go into 8 pages of theoretical. What my smallish brain took from Jake and everyone else's postings: plenum turbulence is bad and at some point smoother air is at least as important if not more than simply MORE air. Not sure what to do with that, tho? Try a bus plenum?

FYI, I did reach out to RC Fuel Injection about cost / recommendation for boring out a 2.0 TB. Looks like the base cost for "most Porsches" is $289. Not sure what that includes, but I'll pass info along. Given that it was late Friday afternoon, I don't expect a response for a few days. Thanks for the tip, Maltese Falcon .

I can offer one data point that may be useful...in reviewing the Microsquirt datalogs for my car, when I rev it up at full throttle I rarely see below 96-97kPa...my GM MAP sensor is mounted on the plenum and has a hose going into one of the big hose fittings in the plenum itself. This implies to me that the throttle body is not really that much of a restriction. Stock 1974 2L D-jet plenum, runner, and throttle body, 2056 with mild street cam.

Rob, I'd be interested in what your data logs show for a full throttle, full-RPM run.

Greg, good idea. I follow your logic. I don't know enough to know if it's valid or not, but I do get the logic, and I'll try to post something soon. I actually haven't done a real run since I put the BMW IAC on it last week and played with the tune, but at WOT nothing should have changed. With Thanksgiving house guests and the colder temps (and heat not currently hooked up on my car) I haven't had a chance to really run it.

EDIT: User tagging not working up in the body of my response for some reason (IMG:style_emoticons/default/confused24.gif)

@Montreal914 @Maltese Falcon