Neill117
|
| posted on 20/7/08 at 04:36 PM |
|
|
Weber tune up
Since I put my car together it has always seemed a bit rich so I decided to have a go at it today armed with a Gunson colour tune and some new
jets.
what it was ....
130 main
f16 emulsion
180 air correct
45f9 idle
40 pump
I changed the jets to...
190 air corrector
40f9 idle
35 pump
Which apart from the emulsion tubes brings it inline with the jets speced in an example in the weber speed pro book.
The car seems to run better and the screws are within 2 turns of totally closed and give a nice blue flame. the car has lost its stink of unburnt fuel
and doesn't pop and bang on over run.
What is does now is between about 2.5-3.5k on the drive (not tested on the road) it pops from the carb. This is supposed to be a lean characteristic
but if i put the colour tune in look at whats happening the pops coincide with yellow flashes so show rich. After 4k the popping stops.
I think this is about the range for the jets to crossover from idle to main so does anyone know how to smooth it out? i tried bumping the mains to 135
and it made no odds. it used to have the odd pop in this range but its allot worse now i have the newer jets in. How can i improve that range or
smooth the crossover?
|
|
|
|
|
cadebytiger
|
| posted on 20/7/08 at 06:58 PM |
|
|
not sure about the progression but my setup is much richer (prob too rich). It was setup on a rolling road however:
Starter Jets F985
Air corrector 180
Emulsion tube F16
Main jet 155
Idle jet 55F9
pump jets 45
Main venturi 36mm
aux venturi 4.5
|
|
|
Neill117
|
| posted on 20/7/08 at 09:34 PM |
|
|
They're interestingly large. Do you have an after market cam? the jets I had in passed emissions at SVA but I found the car stunk of fuel when
running and got a bit lively on overrun. It also ate spark plugs.
|
|
|
cadebytiger
|
| posted on 20/7/08 at 10:54 PM |
|
|
yes. It is running an FR32 i think. The fast road one. I assume we are both talking about pintos.
I get a good amount of popping and banging on the overun. I twas setup on a rolling road by the previous owner but have always assumed it is running a
little on the rich side!
|
|
|
Neill117
|
| posted on 21/7/08 at 10:08 PM |
|
|
Yep, pinto too. I guess i may try a richer idle then to try and sort the progression and see what the mix screws can do.
I noticed that you cant really lean it out too much with the mix screws. There is just a point where its won't burn properly and never goes
white, the cylinder just dies. I guess if i can get it blue and smooth the progression its probably right. I guess its just a matter of what seems
right.
|
|
|
