Mark,

 

Do you have any info on the throttle bodies like brand and source?  Can you expand on problems with the slide throttle?  How thick was the slide?  Thanks for any help

 

Joe Berki

Limo EZ

 

13b P Port

On Saturday, November 24, 2012 7:36 AM, Mark Steitle <msteitle@gmail.com> wrote:
> Doug,

>

That's true.  It is almost like an entirely different engine, especially the MAP readings.  I guess you could compare it to installing a radical cam in your family driver.  It would drastically alter the driving characteristics.  Tracy is working on a fix for the MAP issue on P-Port engines.  It only hits two addresses between idle and 4500 rpm.  Hopefully, the fix will help it to run smoother through the transition.   

>

It also required a whole new intake.  I tried the slide throttle, but there were some issues I didn't especially like, so I built one using three 46mm snowmobile throttle bodies.  It has worked out great.  It especially improved the idle characteristics, probably due to having the primary injectors located downstream of the throttle plates.  I had some fuel pooling issues with having them located upstream.  The snowmobile tb's also operate much smoother than the slide throttle.  At idle, vacuum sucks the slide against the downstream side plate with a significant force, making it difficult to work the throttle.
>
> And... it now burns more fuel than before.  DUH!  I could throttle back and fly slower, but who wants to do that???

>

Mark S.

>

On Sat, Nov 24, 2012 at 3:43 AM, <DLOMHEIM@aol.com> wrote:
>

Mark Steitle wrote:

 

>"...What I can say is that I picked up 20+ knots on the top end over the original side-port 20b motor".

 

That is outstanding Mark!  I'd almost bet that your PP modification was one of the "easiest" ways to gain those hp numbers vs. a turbo / supercharger add on?  Probably wouldn't seem like it as you were going through the "tweaking" phase, etc... :)

 

Doug 

 

>