[Vwdiesel] Re: NA pump on turbo

[HWY9FERGS at cs.com]

In a message dated 3/21/2005 6:35:26 AM Pacific Standard Time, 
vwdiesel-request at vwfans.com writes: 
> I'll be up to my eyeballs in parts soon, so I'll just be in learning mode 
> for the pump 
> stuff until the engine rebuild is done. But my goal is to have it all ready 
> for the May 
> long weekend. (rebuild, plus swap of 2.1 wbx &4 speed with 1.6TD &5 speed 
> into 
> '88 Westy). I suppose I could run the engine with an NA pump for a while if 
> I decide I 
> need to rebuild the TD pump though...
> 
> Shawn Wright
> 
> Hey Shawn!  I'm chiming in a bit late because I'm in digest mode, but here 
> goes.  I'm paying close attention to this one because I am game to tear into a 
> pump.  My 91 eco (no LDA) wants a turbo pump, and I have a used one for it, 
> but want it to be up to snuff with new seals and all before I install. With 
> enough good info here, I imagine I should be able to manage resealing it.  One 
> thing I can say is, the NA pump should actually give you pretty good 
> performance in the meantime if you need to use it because you can increase the 
> fueling with careful adjustment. (I did this with the ECO and it made a BIG 
> difference) I think you can get it to put out as much fuel as the turbo pump at 
> max, it's just that it won't modulate the flow according to boost the way the 
> turbo pump does.  That means, if you mash the throttle, you dump fuel right 
> away (smoke) instead of bringing it in gradually as the boost increases the way 
> the turbo pump does.  At full throttle, assuming the turbo has been able to 
> reach full boost, the turbo and non turbo pumps will be accomplishing the same 
> thing (again, that is if you have turned up the max fueling on the na pump 
> to match the max fueling on the turbo pump).  Let me know if that's helpful to 
> you at all.  Doug