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Re: [alfa] More MegaSquirt and intakes



Messed up on that URL.  It isn't directly linked to my home page.

Click:  http://home.comcast.net/~webb.p/install

Scroll down to see all the thumbnails.  Click a picture to enlarge.

-Peter

> For those following the progress on the MegaSquirt and custom intake...
> 
> I got some pretty exciting numbers on Milano 3.0 with stock intake with the AFM 
> removed.  Much better than I expected.   With the help of Mike Besic of Besic 
> Motorsports, Glen Ellyn IL - (shameless plug for a great Alfa guy) and Ken 
> Baurly of Baurly Auto Sport, Addison IL (full race prep and fabrication shop) I 
> got the new intake built and installed.   Still working on the tuning.  It 
> started first time.  Once I fixed my own mistakes with the air leaks, idled 
> smooth even with the Shankle cams.
> 
> I had a terrible rich stumble right out of the gate.  Turned down the req_fuel 
> number and it was much better.   The VE table was too lean at idle so bumped 
> that up to restore good idle.  Idle is controlled by cracking the throttles a 
> little.  There's no idle air or aux. air device installed.   Most of the MS 
> installations forgo it.  I suppose I could reinstall the AAV some day to restore 
> a better cold idle.   However, I do have an ok cold idle just using the warmup 
> enrichments in the MS.   Still working on that.  After setting the warmups and 
> idle pulsewidths I have a nice smooth idle.
> 
> Next I had to start tuning the VE table.  The initial table ran and drove but 
> was aweful off-idle with some bucking.   Got that tuned so it transistions 
> smooth from a stop.
> 
> Acceleration enrichments can be handled one of 2 ways in the MS, depending the 
> code revision installed.   Generally, acceleration enrichments are determined by 
> the voltage differential of the TPS increasing, using a pot type TPS.  Commonly 
> referred to as TPSdot.  Since I didn't have one of these on the old throttle, I 
> used a custom code mod to determine the differential of the MAP sensor instead.  
> Under heavy plenum vacuum transition it would detect when you stomped on it.   
> Commonly known as MAPdot.
> 
> The new setup uses a pot type TPS from a 155 (also used on the 164QV) so I 
> reverted back to TPSdot accel enrichment and had to change all the settings TPS 
> for voltage differential.  This was difficult to get right but I think I have it 
> close.
> 
> Cruise VE is still a little lean.  Not to the point of melting anything.   The 
> TPSdot enrichment gives me extra squirts even under hard passing acceleration.   
> Not sure if I'm going to leave the cruise lean yet.  With gas prices the way 
> they are, I'm not in any hurry to decrease my general highway mileage.  The 
> programmablity allows me to increase the fueling at higher RPM and load, and 
> three levels of acceleration so I may be able to leave the economy in the cruise 
> and not sacrafice power.
> 
> I'm still working on the high RPM/load VE entries.  This is where I'll make all 
> the power.  I'm still a little lean once the acceleration enrichment squirt is 
> used up.   Not going to bother trying to take any meaningfull power readings 
> until I get this right.  The GTech will help me determine where the best power 
> is during this tuning cycle and the result of each change.
> 
> So the car is running and driving well on a base set of tuning.  It's in 
> semi-daily use in it's current state as I drive around with my laptop trying to 
> the finer points dialed in.
> 
> I've posted pictures of the custom plenum fabrication and installation at:
> 
> <http://home.comcast.net/~webb.p>
> 
> Details on the intake and fueling:
> 
> 164L plenum (powder coated)
> 164L 39mm runners (powder coated)
> 1 155 70mm(ID) throttle w/ Milano bellcrank
> 2 164 70mm(ID) throttles with Weber bellcranks and rods
> TPS on the first throttle from a 155TS
> 3 3.125"(ID) tubes welded to the plenum.
> 1/4" plate for throttle mounting
> Stock Milano throttle cable
> 1.75" silicone turbo tubes plenum-to-runner joints
> 3 3.5x6" K&N filters (and ugly PVC tubes to clear fender)
> 164 Right side cam cover for plenum mounting
> Custom plenum mount to lower cam cover bolt for support
> 6 24lb 350SBC high-z injectors 
> (soon to be 29lb LS1 (Delphi) or 30lb Ford SVO injectors)
> 
> *** no modifications needed to the wiring harness!! ***
> 
> I welcome any comments or questions on the installation.  The plan is still for 
> the installation session at the convention in New Hampshire.  GTV6.org have 
> kindly lent me some forum space to communicate on the event.   It's empty right 
> now so please go over to www.gtv6.org under the forum section for information on 
> the event.  I'd ask you to post your real name and email on the forum if you'd 
> like to participate.  Please include what you want to convert, any details of 
> the car and your level of expertise with tuning and building performance 
> engines.
> 
> Thats it for now.  Article in the Owner eventually.  Just need some time to sit 
> down and write.
> 
> -Peter
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