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<DIV><FONT color=#000000 size=2>Thanks for the info Dave,</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT><FONT size=2>This thing (now that I've
got some other numbers)--runs at 154 BL at cruise. Idle is at 132 (close enough)
---so I'm assuming WOT is going to be pretty lean. </FONT></DIV>
<DIV><FONT size=2>Here's some more specs...Cam duration 283 INT and 286 EXH,
Intake lift is .435</FONT> </DIV>
<DIV><FONT size=2>and exhaust is .455. Compression ratio is 9.4 to 1 and the
heads have been ported to match Vortec specs (this truck is a 1988). 3.42 ratio
diff is what we're working with--and actually the truck peels around pretty good
the way it is...we're just a little concerned about the lean ratio at cruise and
WOT. I'll try adding 15% across the upper end of the fuel map to start
with...</FONT> </DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Lyndon.</FONT></DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 solid 2px; MARGIN-LEFT: 5px; PADDING-LEFT: 5px">
<DIV><FONT face=Arial size=2><B>-----Original Message-----</B><BR><B>From:
</B>Dave Zug <<A
href="mailto:dzug@delanet.com">dzug@delanet.com</A>><BR><B>To: </B><A
href="mailto:gmecm@diy-efi.org">gmecm@diy-efi.org</A> <<A
href="mailto:gmecm@diy-efi.org">gmecm@diy-efi.org</A>><BR><B>Date:
</B>February 22, 2000 9:35 PM<BR><B>Subject: </B>Re: BPW
numbers<BR><BR></DIV></FONT>
<DIV><FONT face=Arial size=2>On a MAF system, if you UP the fuel pressure 7
- 10 %, and set the flow rate to a value 7 - 10% higher, the 305
injectors will have the best chance on a un-hotrodded 350 motor IMO.
you can add 20% more FP and mess up idle and cause BLM skewing, and the WOT
will have more fuel, or you can leave the FP alone and idle will be great
but WOT may have the injectors static and still have low o2 readings.
Either is a comprimise. 305 to 350 = bit more than 14% more air, need
14% more fuel and thats with no other intake mods. If you were using 12ms at
WOT on the 305 you'll use the same injectors 14% longer in the 350 - closer
to static (or over)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>dont just change the BPW by 14%, (in a MAF)
you'll do the opposite of what you are after. the injector base PW should be
the actual setting for the injectors used - then you adjust it a bit for
more FP.. which makes the injectors have a higher flow rate than they are
"stamped". a better spray pattern too. On a TPI (not TBI)
each of the 8 are rated at 19#/hr for a 305 and 22#/hr for a 350. 19 * 1.14
= 21.66 amazingly... keeps the injectors below something like 80% of max
duty cycle.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>and you're "off road" so no problem
with the feds.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Please anyone correct anything. I'm not a pro,
I just play one on TV.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>PS - my soon to be dropped-in 383 will start
out with 350 injectors. (MAF too). </FONT></DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 solid 2px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A href="mailto:nwester@eidnet.org"
title=nwester@eidnet.org>Programmer</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
href="mailto:gmecm@diy-efi.org"
title=gmecm@diy-efi.org>gmecm@diy-efi.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, February 22, 2000
4:46 PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> BPW numbers</DIV>
<DIV><BR></DIV>
<DIV><FONT color=#000000 size=2>Greetings guys,</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT> </DIV>
<DIV><FONT color=#000000 size=2>Just wondering what BPW numbers would do
when a guy changes a 305 to a 350. The 1988 TBI injectors are different,
PROM BPW numbers are 148 for a 305 and 135 for </FONT><FONT
color=#000000 size=2>a 350. This is based on flow in grams/sec...what
would you have to set a 305 injector to, to work in a 350 properly -- or
is the flow rate too low already ?</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT> </DIV>
<DIV><FONT color=#000000
size=2>Lyndon.</FONT></DIV></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>