This is from a mid sixties Aussie hot rod mag...





South Australia

Was done back in th 60,s looking for mythical power increase, generally in constant high RPM applications, speedboats etc, i have pair buried here, will post when i can get to them, You got to realise back in the days of seat of the pants tuning, any mod seemed to go better, but now flow testing is the norm before you start, i think TED may have input re divider removal. I cant remember actual results that long ago.

yyy

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

I guess I have the intake that matches up to that. It's an old Offy intake that I bought about 15 years ago. I used it when I had the 239 first rebuilt. I showed pictures of it to Jerry a few years ago at Columbus, he said that's not good.



  Dennis in Lititz PA

A 2 x 4 Cain intake was tested which has no intake dividers. It didn't do too well.

http://forums.y-blocksforever.com/FindPost46008.aspx

Lawrenceville, GA

Charlie, thats right! If you had engine that had to run at constant High pm range, maybe then it would be better but not good idea.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Back in the 60's in Aus, the Y block was the engine of choice for powerboat racers.
My father spent the family fortune on mods to his engine.
But when I did get around to racing it was definately Chev (sorry) for me as so many performance parts were available.

Gary - 1958 Star Customline and 1940 Ford Deluxe Hotrod

The dividerless Cain intake Ted E. tested, had poor throttle response & a terrible torque curve.The 60s head that Slick just posted, is back in the "hog the ports out" era.. a disproven method long ago.

Paul

Removing the port dividers is a good way to wreck what could have been a good pair of heads. Low end torque numbers go out the door without seeing an increase in peak horsepower numbers and in most instances, overall performance suffers. Here’s the link to the CAIN intake manifold testing which is essentially the same scenario except the runners are removed from the intake instead of the cylinder heads.

---

http://forums.y-blocksforever.com/FindPost46009.aspx

Lorena, Texas (South of Waco)

I too talked to Jerry Christenson some years ago about eliminating the divider between the runners. His thoughts at the time were that it would be a negative for the lower rpm range and perhaps a positive for the higher range. My thinking at the time was anything that helped the top end performance was all I needed to be concerned about. However, on the shorter tracks it is almost a drag race to get the best time possible.

His thinking was that the intake runners would experience great reversion at the lower rpms. This would be due to the reverse pumping of the air/fuel caused by the intake valve opening while the piston is approaching TDC, therefore lowering the torque and HP. This should diminish as the rpm increases, but little was known if the high end performance would surpass a divided runner in a head that was expertly ported.

Land speed racing might benefit from some testing, but with few trips down the track at a given event, I doubt anyone would use the track for a dyno. Perhaps some time on a conventional dyno or a chassis dyno would give some insight.

Charlie Burns Laton, Ca (South of Fresno)







BurnsRacing981@gmail.com