>Marc Tyler
> The stock downdraught intake manifold opens into a common chamber, but
> i can't imagine that would be the case for a DCOE manifold, that would
> put the carb well into the wheel well of a 411 ;-) Here's a pic of a
> 520's J13 with a DCOE carb. The Manifold has separate runners. Who
> ever's truck this is, he's got the stock exhaust manifold installed so
> i doubt that big honkin' carbie is buying him much
If the head's restrictive I doubt the exhaust manifold's gonna make much
difference. Any engine is limited to what the most restrictive point in the
system will flow. That was the problem with putting the SSS/twin SU intake
setup on stock US spec L-16s in the 510. The SSS manifold has 1 1/2 inch
runners and the ports in the head were 1 1/4. Not only would the flow be
slowed by cramming the 1 1/2 inch air column in the manifold down to 1 1/4
inch at the head, but the flat 1/8 edge hanging out in the air stream at
that point created eddies and swirls that disturbed the air flow even more.
Geez..., too much theorizing. I'll be very glad when we're out of this
apartment and into our own place again, with the requisite shop next door of
course, so I can get going on the cars again.
FWIW,
Ron
Ronnie Day
rday@hot.rr.com
Ronnie_day@acd.org
Temple, TX
***********************
'71 510 2-dr (Prepared Class Autocrosser)
'73 510 2-dr (Street Toy)
'70 2000 (on hold)
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