[Diy_efi] RE: RE: New to list, have a question about speed density and turbos

[Startled Jackrabbit]

Thanks everyone for the replies!

Ok, lemme just clarify:
sy2th wrote:
>If you're 
>gonna use speed density, you won't >use your MAF
sensor at all, nor >will your engine care what the TPS
>says - MAP is MAP. 

So basically, given that I can reach full boost at
say, 80% throttle, then all 100% would add would be to
allow the engine to reach full boost faster?

That really helps alot!

A6intruder wrote:
>Why is speed density any better?  >I would think
particularly in your 
>case, a properly sized MAF before >the turbo would
simplify your >computations. You would have >accurate
info on what is going >into the turbo and only have to
>correct for air charge temp after >the turbo.

I agree that it would simplify the computations, but
tuning it would be very difficult.  the output of the
MAF is not linear, and short of a wideband O2 sensor
(which I amm trying to avoid using), or flow bench
testing the MAF, I would have to tune a VE-like
conversion table for the MAF frequency just going off
of EGT's and knock.  Cruise ranges would be easy since
I can use the stock O2 sensor.
I figure, if I'm going to have a correction table to
tune, I might as well use speed density and remove the
fairly restrictive MAF alltogether.  This has its
advantages, especially as I start reaching higher
boost levels, the 1st gen MAF's would eventually be
overrun, and many DSMer's switch to the 2G MAF (way
more expensive than a MAP sensor).

Again, thanks for the input!
Further ideas are of course welcomed!

Over and out,
JeremyB.

__________________________________________________
Do you Yahoo!?
Y! Web Hosting - Let the expert host your web site
http://webhosting.yahoo.com/

_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://www.diy-efi.org/mailman/listinfo/diy_efi