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Re: UPDATE, Swapped to carb to rule out ignition.. and pseudo-intro..



I have only converted one car from carbs to FI.  It was a Jag straight 6 from 
two 2inch SUs to port injection.  Low end grunt improved (according to the 
butt-o-meter) and 'around town' fuel economy improved dramatically.  But the 
top end did not feel nearly as quick (again, according to the butt-o-meter.)  
And I used to get rubber in second, and never got it with FI.  Yet, my 
stop-watch timing to 60mph showed a good 1-second quicker (the low end grunt, 
maybe?)
But I really missed that top end screaming that put you back in the seat 
(well, relatively speaking, given the 4200 lb sedan with a 6cyl).
It wasn't a restrictive throttle body ( 3 inch) or to small injectors (24lb). 
 It just seemed the nature of the FI.  Maybe it's the long runners, I don't 
know.
Now I have a Chevy v8 that I am going to switch to TPI.  This car pulls real 
hard on the highway, but is kinda wimpy in first gear (stumbles a lot, I 
don't know why).  I'm hoping I get the Fuel economy gains and the low end 
grunt, but I will be very disappointed if I lose the high end pull.  (and by 
high end pull, I mean from 3500rpm to 5000rpm.  The auto. doesn't really let 
it do much more than that, and I'm going 100mph by then anyway!)  Also, 
basically stock engine ('75 L48 with a 4 bbl.)  It was rebuilt at some time, 
so maybe it is slightly hotter than stock, but has a smooth idle and 
absolutely stock on the outside.  0-60 is about 9 seconds (when it doesn't 
stumble to much in first gear) but 60 to 80 is 5 seconds flat, which is 
pretty quick.  1/8 is 10.3 at 69mph (it's only just starting to get moving!)
So to sum up, my experience so far has been similar to yours.  I hope the 
trend doesn't continue with my TPI.  Maybe someone on this list knows why 
this is, or can just tell us to stop using the But-o-meters?
Ted
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