ITB project, Honda VFR 800 ITBs Options

[kevin311]

I've been running Megasquirt II for a while now on my 71 1.7 with the stock D-jet components and it has been running well. But everything is looking tired in the engine bay and I am planning on taking out the engine to clean everything up and install SS fuel lines.

Then I remembered seeing a video youtube with an australian guy reviewing his 914 and he mentioned having GSXR ITBs on his car. Sounds like a fun project to me so I started researching and think I have found an even better solution.

The throttle bodies I found are from a 2001 Honda VFR800. The bike is a V4 so the TBs and fuel rails are already split into pairs, and have a linkage that connects both. They have 37mm throats, and came with the throttle position sensor, fuel pressure regulator , injectors and and all the wiring and connectors. Also the brackets on the sides already have a tab for throttle cable.

The injectors are high impedance so I wont have to run PWM on Megasquirt anymore and hopefully can get an even finer tune.
I'm also thinking about switching the PCs for 96mm, but I think that will wait until later, but you never know this started out as an engine cleaning...

The only things I need to figure out are the flow rate of the injectors, where I'm going to hook up the IAT sensor, and will need to build a vacuum plenum. Also these injectors run at 36 psi, can the stock fuel pump handle that or do I need to look for another solution?

Here are some pics, check out how close the spacing is for weber manifolds.
Please excuse the dirt. I still haven't cleaned them up.

This is gonna be fun. (IMG:style_emoticons/default/beerchug.gif)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i694.photobucket.com-11752-1345224315.1.jpg)

(IMG:http://i694.photobucket.com/albums/vv310/Kevin31188/DSC03555.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i694.photobucket.com-11752-1345224325.2.jpg)

(IMG:http://i694.photobucket.com/albums/vv310/Kevin31188/DSC03552.jpg)

(IMG:http://i694.photobucket.com/albums/vv310/Kevin31188/DSC03558.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i694.photobucket.com-11752-1345224346.3.jpg)

(IMG:http://i694.photobucket.com/albums/vv310/Kevin31188/DSC03559.jpg)

[aircooledtechguy]

I don't think you'll need to be too worried about not being able to tune this well since most folks who do this type of thing are using GSXR TBs that are 40mm. As Dave has explained, it's apples and oranges between plenum and ITBs.

I'm planning on going to ITBs with the Squarsche and had seen these same TBs on eBay but was wondering if the distance center to center for the IDF manifolds were even remotely similar. After seeing your photos in your first post, I can see that they are close enough to warrant buying a set. Thanks for posting this. (IMG:style_emoticons/default/beerchug.gif)

BTW, I have an aquaintance in TX that is running a 2056cc in a VW Notch with GSXR 40mm TBs and he's getting around 40-42mpg (hwy) with his MS tune and has gobs of power on tap when he wants it. So YES, MS can be tuned easily for these to work on your motor. Nothing better than making 30s technology work better than the boys in Detroit can do it on new cars. (IMG:style_emoticons/default/happy11.gif)