Crossfire Injection Question

[Brent Obermiller <ober_b@sssnet.com>]

This is a question/comment w/ regard to the Crossfire.  I
got my manifolds out of storage yesterday and looked at them
again, the first in a long time.  First, as I mentioned
before one has holes (14057017) between the runners and one
doesn't (14031372); these being the casting no's for what I
beleive are 82/83 Camaro/Firebird 305 manifolds.  Now my two
questions:  Should I be concerned about how small the
manifold ports are compared to even my stock 92 swirl-port
head ports; That is, there is about a 3/8 to 1/2 inched
difference in port height.  I'm under the impression that
the cross sectional area should get smaller to increase
velocity into the port, not only is this the other way but
the transition is abrupt (i.e. mismatched).  2nd, does
anyone know what the lobe seperation angle is for most gm
TBI's apps?  I know the L-98 and LT-4 are 114, which is what
I'm running (LT4), obviously this works for port injection
but is it to wide for TBI?  I'm told that's wide for carb,
and since TBI is wet manifold I wondered if there was any
correlation.

-Brent

Okay someone will ask, so: 4400 lbs, 5.7L, 670cfm Holley,
Stock TBI manifold opened to 2" bore, trickflow heads, LT4
cam, 55lb injectors, 700r4 (95 Impala SS convertor), TPI
exh. manifolds w/ 87 monte ss head pipe in single 3" cat and
exhaust, 3:42 posi
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