<VV> engine names-no corvair

[Tony Underwood]

At 07:03 PM 7/16/2010, djtcz at comcast.net wrote:
>Sonoramic Commando
>
>http://www.allpar.com/photos/bios/weertman/sonoramic-commando.jpg
>
>
>http://www.allpar.com/images/plymouth/1960/ram.jpg
>
>
>Only the Turbocharged Corvair dared exposed any where near so much 
>naughty intake manifold for all the world to see.



...got a couple of these intake systems in my basement.


There were two different types, both of which looked almost 
identical.  One had runner dividers longer than the other.    The 
extra intake plumbing  that wasn't divided acted more as a plenum 
than anything which would behave as a tuned ram inducing 
runner.   The divider made the difference.    This meant that the 
tuned length of the runners were different depending on the length of 
those dividers.

One had 11" long dividers that made max torque at 4000-4500 rpm and 
was intended for high speed performance.   The other had dividers 20" 
long which made max torque (nearly 500 lbs/ft) at a relatively low 
rpm, around 2800.   This intake was great for street use and had an 
interesting surge of "umph" when you nailed the throttle to pass someone.

It also sounded amazing.  :)

Interestingly enough, Chrysler radically modified their Cross-Ram 
intake system in 1962 to shorten its external dimensions so it would 
fit under the hood of the B-body line of cars (Belvedere and Coronet) 
without hitting the fender wells.   This intake eliminated the extra 
runner length and ended up no wider than the engine itself, although 
it retained the hi-perf 11" long dividers and was used on the 
Stage-1, II, and III series Max-Wedge engines.   It was also a 
one-piece design that was less complicated.   This same intake design 
migrated to the first 426 "race" Hemi engines in 1964 which were 
somewhat vicious with very high compression, radical cams, and a pair 
of 750 cfm Comp series AFBs on the intake.   The 4000+ torque peak 
worked out well for Superstock racing and to this day the record for 
SS/A-A is held by a Barracuda with a Race Hemi engine sporting this 
same intake.    It is not very practical for street use except for a 
weekend warrior, and even then unless it's allowed to buzz 6k or more 
it will still often get outrun by something newer with just a single 
carb, like the intake that comes on the "crate" 426-465hp street 
hemi.    But, let it sing, and the results will set you 
back.   Literally.  ;)  And, it is still used on the "crate" 
426-580hp race hemi which was sometimes (to remain sorta topical) 
called "The Elephant".

Chrysler advertised BOTH 426 hemi engines at a somewhat unbelievable 
425hp.   I have a 1965 factory dyno report that showed the prototype 
model street hemi as producing 463hp at 5200 rpm with a torque curve 
of over 300 lbs feet between 1900 rpm through 5000 rpm with a peak of 
496 lbs/ft at 4200 rpm.

How many standard induction streetable automobile engines will do 
that regardless of vintage?

NHRA rated the street hemi at 470hp for class drag racing.  The 
current 426 street hemi in crate form from the factory is rated at 
465hp but people who put them on a dyno got between 470 and 490 hp in 
original factory stock form.
The race hemi, according to dyno tests, put out (depending on who ran 
the dyno) between 580 and 590 hp with a single large NASCAR approved 
carb.   With the dragrace tuned crossram mag intake it would bump 
610hp.   This is with 1964 tech.   Current Superstock race hemi 
engines can produce 850hp... on gasoline... and pass a tech 
inspection for its original 1968 factory stock specs... and propel a 
1968 Barracuda down a 1/4 mile in 8.6 seconds at over 150mph.   I can 
remember when many Top Fuel dragsters were having to work pretty hard 
doing that.

It was Chrysler's experimentation with ram induction and improved 
combustion chamber designs on street engines in the '50s and '60s 
that led to a lot of advances in driveline design for American 
performance automobiles...  which is something from which a stock 
Corvair cylinder head could sorely benefit.




tony..