[johnta1]

Also, didn't the RAIV have a stronger bottom end whereas the 455HO did not? IMO the SD455 is a substantially improved 455HO, with all of the goodies. Besides the low compression and emission controls, I've always felt the 455HO Achilles heel was with the STD bottom end; which limits the top end of the RPM range.

I always figured the 455 HO was like an interim set up until the SD got going.

Too bad Pontiac got caught by the EPA with the SD455 emissions and had to re-work the engine to pass. Makes me wonder if some Chevrolet/Corvette spy didn’t send a little note to the GM brass; or the EPA itself.

Chevrolet ruled the roost.

what cam did the S.D. get?...its own special design?,or a previous one?...what is involved in making the dry sump functional?...does the motor need to be pulled?...anyone here ever hook theres up?!

It was supposed to be like the RA IV cam, but it ended up like the 9785744 cam.
The SD cam had a smaller gear on it for the distributor.
(distributor gear was bigger and engine had bigger distributor hole)

There has been at least one set up to use the cam gear pump.
The pump housing is at the rear of the engine, so engine has to be out for it to work.
There used to be a company that made the gears to use in it?



The SD and the RA V engines were probably the best thing coming out at Pontiac at that time.