Wednesday, July 25, 2012

Do research before you start spewing insults.......

Had several idiots email me after yesterday's post telling me I was "dreaming" about the idea for low-budget fuel-injected Pontiac and Olds engines. The one genius said that although the intake off a 350 Seville would fit a 350 / 403, it wouldn't work for high performance, since the late '70s Sevilles weren't known for their blistering acceleration. 1st off-the late '70's Sevilles weighed about 4,200 lbs, had 8:1 compression, and 2.41:1 and 2.56:1 axle ratios. I proposed a 78-88 "G" body Cutlass which weighs about 3,300 lbs, and I said "With proper cam, compression and gearing you could run in the 13's and get 20 mpg."  That means a 3.42:1 or 3.73:1 axle ratio, an overdrive transmission, 9.5:1 compression, and a "Torquer" cam-ala' Edelbrock Performer.  As for the fuel injection system- this one works like a big two-barrel carb-you could port-match the intake to the heads, for a little extra airflow, and Cadillac used the same throttle body to feed the 425 and 500 inch engines in the Deville and Eldorado lines from 75-78. If it could feed a 500 inch Cad engine properly, it should have no problem feeding a mildly modified 350 or 403 Olds. And-duh-you can use an electric fuel pump and a pressure regulator to adjust fuel pressure. to the engine's needs. Plus-your only accentuating what Olds and Cad engineers did to begin with-make big torque at low rpm. The engine would probably be redlined at 5,200 rpm max. This would actually be a pretty easy project to do, if you could find a Seville donor car for the engine, or at least the induction system in a junkyard.  As for the Pontiacs-the Offenhauser Dual-Quad 4bbl manifold has a spread-bore bolt pattern. I have seen people use Carter AFBs, Edelbrock Performers, Holleys, and even Quadrajet carbs on these manifolds. It wouldn't be hard to buy or make an adapter to bolt up 454 Chevy TBI throttle bodies to the carb pads. Nor would it be hard to fabricate a progressive throttle linkage. Since Corvettes used large-cap HEIs until 1989-it wouldn't be hard to hook up a 1984-"Cross-Fire" injection PROM to a Pontiac HEI distributor, or if you had to use a small-cap HEI for clearance, a 1990 and later TPI 'Vette Prom or a 1990-93 SS454 truck PROM would provide the fuel curve you'd need for a 400 inch engine. Plus Hypertech and other companies will make you a custom PROM chip for a reasonable fee. It wouldn't be a bolt-on like the 350 Olds setup, but it's not rocket science either. Any competent mechanic could probably do it.  The other setup I proposed would be even simpler-a high-school metal shop or foundry could cast a baseplate from the bottom of a Pontiac intake and the top of a Small-block Chevy TPI baseplate. Edelbrock offers hi-flow runners and trick flow and other companies offer 58mm throttle bodies, and high-flow injectors. Many people run TPI systems on 383 inch Chevy engines, so it can feed a 400 Pontiac pretty easily. Again-this would be a torque monster-I'd set shift points at 5000-5,600 rpm depending on the engines state of tune. Use a Corvette PROM, and the 85-88 MAF system which is infinitely more adjustable and adaptable to modifications than the 89-92 Speed Density system.  I wouldn't have a 16 year old attempt it, but a competent mechanic could make it fly pretty easily.  I'm thick-skinned, but I wish people would think before they start spewing about wrong you are. Mastermind     

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