How smart is Holley Sniper EFI?
#21
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It was season 3 episode 39. I think their analysis was that the jets shoot down under pressure and the fuel can't make the turn. Get a subscription to Motor Trend it's worth the money. Over the seasons they have tested everything I've done and I'm feeling pretty good about my choices. They do a lot of testing on BBC so we can learn a lot.
#22
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weiand stealth and regular performer intake. % or so years ago a friend brought a 502 to dyno, small cam, vic jr intake. motor was a zz502 he had got cheap and fixed up. motor made a embarrassingly low tq number for a 502. We bolted a ported performer on, picked up tremendous torque AND top end hp (only hgad power to 5400/5500). #3 was burn down lean, #2 was pig rich, talking 4+ afr points apart. we monkeyed with carb spacers, still sucked. He bought a perfomer rpm, picked up even more tq and hp, 2 was like 11.5, 3 was like 13.5 give or take, half as bad.
Fast forward, guys building a similar engine, asked what he should get, I told him a perf rpm, he couldn't get one, so he bought a weiand dual plane. Same deal, 2 in low 10s, 3 in almost the 15s. tried a couple spacers, made no difference. Compared a stock carbed 502 intake I had to his weiand, they were a mirror image of each other BUT the factory intake had little ridges/troughs turning the sharp corner to 3, I assume to help fuel distribution. We looked at a beat up, nasty perf rpm I had, the turn to 3 was much more radiused and port to 2 much smaller than the other 2 , as if they actually put some thought in the design. We found a new perf rpm online, ordered it, swapped it on, picked up tq/hp over the weiand (like around 15/20 at peaks) and again, distribution was half as bad as the weiand. If anyone calls and wants to dyno a marine engine with regular dual plane in future, Im pretty convinced theres no real good way to fix the fuel issues, Smiitty
Fast forward, guys building a similar engine, asked what he should get, I told him a perf rpm, he couldn't get one, so he bought a weiand dual plane. Same deal, 2 in low 10s, 3 in almost the 15s. tried a couple spacers, made no difference. Compared a stock carbed 502 intake I had to his weiand, they were a mirror image of each other BUT the factory intake had little ridges/troughs turning the sharp corner to 3, I assume to help fuel distribution. We looked at a beat up, nasty perf rpm I had, the turn to 3 was much more radiused and port to 2 much smaller than the other 2 , as if they actually put some thought in the design. We found a new perf rpm online, ordered it, swapped it on, picked up tq/hp over the weiand (like around 15/20 at peaks) and again, distribution was half as bad as the weiand. If anyone calls and wants to dyno a marine engine with regular dual plane in future, Im pretty convinced theres no real good way to fix the fuel issues, Smiitty
https://www.summitracing.com/search/...take-manifolds
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articfriends (08-24-2022)
#23
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Looks like the BBC RPM rect port's are back in stock. Note, the air gap's don't seem to be yet.
https://www.summitracing.com/search/...take-manifolds
https://www.summitracing.com/search/...take-manifolds