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1981 Cadillac Deville
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Discussion Starter #1
I Have a 1981 v864 Deville, the system works fine, an I was poking at a few ideas for a future project.
I heard the v864 rocker assembly will mount up to an Oldsmobile 307/350/403, can I get the system to work on one of those engines with some modifications? The idia is for more economy and possible performance mods, with keeping the old mpg sentinel.
 

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1980 FBC
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If you search this place carefully you might find a few old threads on the subject. I remember a few kids who were going to take over the world by fitting a modulated displacement setup to a 500.

One problem with that concept is the modulated displacement really didn't save that much fuel in the first place. Maybe 10% with a tail wind.

Another problem is the way the intake manifold behaves with 4 flows missing.

You want performance without ruining economy? Retrofit a 4L80e and 3.23 posi rear axle.

If you can get your hands on an Olds 403 I'd just use that and forget economy to a point. One of the best engines Generous Motors made.
 

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1981 Cadillac Deville
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Discussion Starter #3
Great thoughts, might just be what I end up doing, but here's what I had in mind
Combining a 290hp olds 350 with V864 (if possible), Seville EFI intake, and a suped up 200r4
Hopefully it could retain V4 and overdrive
Also, would the computer compensate with 350 injectors?
 

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1980 FBC
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8/6/4 will probably not play well with overdrive.

I'd just hang on to the parts. Someone will NEED them someday.

Olds 350 and 70s F.I. intake with modern retrofitted Megasquirt sequential injection and ignition controls would be your best bet for performance AND economy improvements. The factory 70s EFI computer was great but does not have a lot of leeway for more fuel delivery.

The 2004R is not a stout transmission and is tough to get a good full throttle shift from without all the expensive Grand National parts.

There's no way to go forward here without buxxxxx.
 

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Eldorado
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Great thoughts, might just be what I end up doing, but
here's what I had in mind. Combining a 290hp olds 350 with V864 (if possible), Seville
EFI intake, and a suped up 200r4. Hopefully it could retain V4 and overdrive
Also, would the computer compensate with 350 injectors?
Why don't you just use a 1981 864 368 engine complete? The valve modulators won't fit
an Olds, or I would have done it a long time ago. The valves are spaced differently.
Maybe they will fit an Olds aluminum head?

Some 864 on 500 conversions have been done with a CARB with streetable results. Using
a computer is really going to complicate the whole picture; the transitions between
# of cylinders are very difficult. Yea a Seville manifold fits an Olds, but the ECU isn't
easily adjusted and not set up for such things. Those cars had relatively large, low
impedance injectors, because the duty cycle could never exceed 50%: no overlap
possible between the 2 banks (of 4 injectors).

If fuel economy is the goal, first thing is get set up with an overdrive lockup trans
that keeps cruise rpms low and eliminates converter slip. Even the 864 didn't eliminate
the slip, you might do even better. Bruce Roe
 
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