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: Rectangular port versus oval port heads? 70ECam Apr 22nd, 04, 4:44 PM I have a set of each heads (rect. being original) for a 396 and am curious about where the horsepower and torque curve lies with each. If the same head work and valve train were used what are the pros and cons of each set? This is for a '70 El Camino and I doubt I'll ever run the quarter in it. All facts, opinions, and personal experiences welcome! GRN69CHV Apr 22nd, 04, 5:10 PM Search this one and be prepared for a lot of reading. In reality, put the recs on the shelf for the day you build a 500 incher. NYCRAT Apr 22nd, 04, 5:38 PM Chevy High Performance July 2003 Pg 50-59 does a head to head oval vs rectangular ovals beat em across the entire spectrum (test was geared for a street motor) 2.19/1.88 (both) 220*@.50 .500 115 lsa oval avg tq 451 rec avg tq 437 oval avg hp 388 rec avg hp 376 Then they added a blower oval avg tq 609 rec avg tq 602 oval avg hp 523 rec avg hp 517 Andy 68chevelle533 Apr 22nd, 04, 6:27 PM I think the ovals are probably the right choice for most street 396 motors. The ovals are suppose to beat ret port heads to 5500 and then the ret ports start to have an edge, and that is on a 454. If you put bigger valves in the oval port heads and had a nice street port job performed IMO that would be the best bet for a street 396. 427L88 Apr 22nd, 04, 9:21 PM Andy, one thing about that test that 'blows' ( other than the blower, is that especially N/A, the rect port is going to much prefer the higher charge velocity of a tigher LSA cam. I realize they might have done that 115 lsa specifically for the blower, but N/A its a real hinderance to larger/slower inlet ports IMHO. Mike Feudo Apr 22nd, 04, 10:24 PM Use ovals on a 396 unless it is a very serious motor. 70ECam Apr 22nd, 04, 11:55 PM Thanks for all the input. I just hate to see those rect. port heads sitting on the shelf. Got plenty of holes to patch in the body first anyway, so there'll be time to plan the motor. That's when all of your builds will come in real handy. graemlins/thumbsup.gif 70BB Apr 23rd, 04, 12:09 AM I'm running the Merlin 310cc rectal ports on my (10:1) 496 .All I can say is "she ain't no slouch". Wooderson Apr 23rd, 04, 1:00 AM I've ran both types on my 454. Either one will incinerate street tires. When I posted my ET differences a few years ago, the thread got out of hand and was eventually locked, so you'll have to guess at what each head ran. smile.gif NYCRAT Apr 23rd, 04, 2:32 PM 427L88, Wha?? :confused: your talking Greek to me. I don't know (or pretend to)enough about cams to understand what your talking about graemlins/clonk.gif I just read the articles...... ;) Andy | ||