NASCAR engine options

[boss429kiwi]

Hi

Just a thought, was the 440 engine in the Superbird or Daytona ever used for NASCAR racing? Or was it always the 426?

Thanks
Gary

[pettybird]

Hi

Just a thought, was the 440 engine in the Superbird or Daytona ever used for NASCAR racing? Or was it always the 426?

Thanks
Gary

there was a 7 liter limit then, so no 440, but the 426 with Max Wedge heads did work pretty well.  since the hemi was legal there wasn't a point to running without it, but I'm sure some privateers made due.  Paging Doug S....Doug S to the vintage NASCAR help desk...

[Aero426]

Once the 426 Hemi was established and lots of parts were in the user pipeline there was no reason for anyone to run the 426 wedge.    But in 1971 when restrictor plates came in, both Ford and Chrysler teams went away from the Hemis back to the old 426 Wedge and 427 Tunnelport because they got a larger plate opening.    Because of the 7L limit, no 440 CI engines would have been legal.

[boss429kiwi]

Oh course, the 7lt limit...................what was I thinking! 

[learical1]

I'm sure Doug will correct me if I'm not remembering correctly.

For 1971 (at the beginning of the season):
7 liter engines = restrictor plates (wedge heads bigger holes in the plate, hemi heads smaller holes)
6 liter (366 CID) = no restrictor plates
5 liter (305 CID) = no restrictor plates [required size for limited production Aero cars]

Ford had run the 427 Tunnelport as recently as early 1969, and there was already plenty of development on this engine, so it was a quick and easy step to return to the 427 from the Boss 429.  Now, Mopar hadn't run the 426 Wedge since 1963, and they were way behind the 8 ball.  Hemi blocks, like the side-oiler Ford 427's, had cross-bolted main bearing caps for strength at hi RPM's; 426 Wedge blocks were not cross bolted.  The Mopar teams welded up the Hemi block (where the stud from the bottom of the intake port passes through) to take a bolt.  From what I read, the Mopar teams used 440-6bbl head almost straight out of the box, not the Max Wedge heads because the new intake manifold had the smaller ports.  The Ford boys screamed that Mopar never made a cross bolted wedge block, Mopar said Ford never built a street tunnel port engine.  Nascar told them both to shut up and race.  

[hemi68charger]

....  Nascar sold them both to shut up and race.