[Supras] REG Lex AFM bypass screw

[Wade Tobin]

I thought the main reason for the screw was to allow head to go flush with the inside body?  This would raise fuel cut some over the stocker which doesn't go all the way out.  
   
  A few years ago I did some testing with the Lexus AFM screw using the LM1.  I found that  all the way out only changed .5% A/F at idle and .2 at the WOT.  Also, the car never changed it's running/driving characteristics much during the test.  So, mine's been all the way out ever since.  Setups can vary so much with FPR's, biggie backs, injectors, turbo size, and altitude.  THe screw, IMO, is pretty useless by today's standards - mostly from improved piggiebacks.  But, if you run the exact same setup as Reg then the screw is probably a good idea.:)

  -wt
Dan Gyoba <dgyoba at abstractconsulting.com> wrote:
  On 4 Sep 2007 at 20:00, berniek at technicaldevelop.com wrote:

> From everything I've read, the objective reg had was to lengthen the
> screw to lower the air bypass flow.

This is exactly the objective. The Lexus AFM isn't exactly right for the 550cc 
injectors, it still depends on the ECU's mapping ability to some extent.

With the stock Lexus screw in place, I occasionally get ECU code 31. This generally 
happens at idle, particularly after hard runs, though not always. I suspect that 
what is happening is that the air speed signal from the ECU is too low. In this 
case, a longer screw to tune the AFM with would be a good thing.

Now, though I know that Reg did have the screw created specifically for this purpose, 
I do think that $100 is a bit much for what it is, and there must be a more 
economical way.

I have some other issues that I need to clear up before this becomes a priority. My 
Lexus/550 swap so far isn't being used yet (I'm still running stock boost on the 
stock turbo) but it's there.

Dan Gyoba
'89 NA 451,732 kms, Turbo swap COMPLETE
http://www.abstractconsulting.com/~dan


_______________________________________________
Supras mailing list
Supras at supras.com
http://supras.com/mailman/listinfo/supras_supras.com


       
---------------------------------
Yahoo! oneSearch: Finally,  mobile search that gives answers, not web links.