>Sounds like you have some hard data to back that up with. I currently am
>running a bone stock (junkyard pullout) 1980 SD1 3.5l, with a 4bbl buick
>intake(with adapter plate) and a Holley 390. Installed the Holley straight
>out of the box, just set the float level, and go. Carb. seems to flood at
>idle, and seems to run very rich. What jets does this carb come with stock,
>and which are preferred? Also, engine seems to cut out at high rpm. Can't
>tell if its fuel starvation, or whether its valve float. (no working tach
>yet!) I am running a Autozone generic electric fuel pump throught the stock
>TR7 fuel lines.
Flooding at idle can be due to many things:
misadjusted floats
blown power valve
too low a power valve opening point
too rich an idle mixture
ignition problems
Don't have the jet diameters for the 390 handy but you can email
holley and they will be glad to tell you. You'll want to convert to
removable secondary jets. Also, convert to the quick change
secondary spring kit and put in the power valve check ball protection
kit. Find the proper power valve with a vacuum guage then play with
jets and springs. The PVCR's may also need adjusting. Luckily they
are small so can be drilled out. Usually they are too large and have
to be epoxied shut and re-drilled. I also like the quick jet change
bowls but they require center hung floats (also a good thing to have).
These can be had by picking up a cheap trashed swap meet Holley
with center hung floats. Too much to Holley tuning than I can write here.
I started a tuning guide. I guess I should get back to work on it.
Make sure the ignition system is in top shape before messing with the
carb. Also make sure fuel pressure is within bounds.
>PS-the 4bbl buick w/adapter creates some clearance problems with the hood,
>with all but the slimmest air cleaners, is the Edelbrock any lower? (or
>HIGHER?)
The Edelbrock and Carter AFB's are lower than the Holley and
don't require the adapter plate so you can run a taller filter
element. There are also drop base filter cases. This may be
part of you problem at higher revs. The filter may be choking
off the air supply. Try running it with no filter. I'm working on
a remote air cleaner set up for the Pantera which I'll probably
duplicate for TR7V8.
Later,
Dan Jones
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