Analysis Paralysis
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Double ck on valve size vs pistons. Are those 2.25" intakes? Gonna need a wide valve pocket for radial clearance.
Sounds like you'll be happy with that cam considering your needs for idle and smoothness. It will still thump a little.
You might look at Brodix intakes also......they make some nice flowing dual planes also. A regular Performer might be a restriction. How many cubes did you decide on?
JIM
Sounds like you'll be happy with that cam considering your needs for idle and smoothness. It will still thump a little.
You might look at Brodix intakes also......they make some nice flowing dual planes also. A regular Performer might be a restriction. How many cubes did you decide on?
JIM
We looked at the Brodix intakes but the earliest they make power is 2,500 rpms. The Eddy Performer RPM starts at 1,500. I didn't specify the RPM version above but that's what I meant.
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You don’t want shorter pistons. You want them as close to zero deck as possible. Mine actually stick .009” OUT of the hole!
You’ve got to get pistons with enough radial clearance. Either made into them or you need to cut them on a mill or with a cutter using the head as a template.
It’s entirely possible the cam you have is mild enough the piston and valve wont be close but you MUST check during the mock up stage. Ask whoever is making pistons if they will clear a 2.300 valve which is much more common these days. I had to open my pistons up to clear my 2.350 valves.
Its not the depth of the pocket it’s the edge clearance.
You’ve got to get pistons with enough radial clearance. Either made into them or you need to cut them on a mill or with a cutter using the head as a template.
It’s entirely possible the cam you have is mild enough the piston and valve wont be close but you MUST check during the mock up stage. Ask whoever is making pistons if they will clear a 2.300 valve which is much more common these days. I had to open my pistons up to clear my 2.350 valves.
Its not the depth of the pocket it’s the edge clearance.
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2020 C2 of the Year - Modified Winner
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2017 C2 of Year Finalist
And on the intake you’re not going to be going wide open throttle at 1500 rpm. You’ll be at 3-4K RPM in a nano second.
Big misconception on cams and intake power ranges. Yes a small one will be responsive off idle but it will choke up as RPM increases.
When I ran my 427 I usually had a strip dominator single plane on it with. 256* solid flat tappet with .600 lift on a 110 LSA. Worked great. Later with a set of well ported iron Merlin oval ports flowing similar to your new heads I ran a Comp 288 street roller. It’s a solid roller with 244/244@.050 on a 110 LSA and .623 lift. REALLY great combo. Peaked HP on chassis dyno at 5850 RPM but only dropped 6 HP at 7000 RPM. Incredible RPM spread made it pull from any speed and held great vacuum.
Big misconception on cams and intake power ranges. Yes a small one will be responsive off idle but it will choke up as RPM increases.
When I ran my 427 I usually had a strip dominator single plane on it with. 256* solid flat tappet with .600 lift on a 110 LSA. Worked great. Later with a set of well ported iron Merlin oval ports flowing similar to your new heads I ran a Comp 288 street roller. It’s a solid roller with 244/244@.050 on a 110 LSA and .623 lift. REALLY great combo. Peaked HP on chassis dyno at 5850 RPM but only dropped 6 HP at 7000 RPM. Incredible RPM spread made it pull from any speed and held great vacuum.
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Thanks gentlemen. I spent the evening researching P/V clearance. I get it now. Certainly I will check while mocking. The good news is I can get the smaller 2.190 valves with little effect given my mild specs. That should help clearance but I like the idea of also contacting the piston manufacturer to ask about clearance. Apparently this hurdle is really just part of the process/fun.
Last edited by C2lover; Sep 9, 2024 at 09:53 PM.
Old Pro Solo Guy
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From: Marlton NJ
You are gonna like that combo.
Great heads make the power. That's your best 1st choice.
Then you can keep the cam just a touch milder, at 224, vs 230, and have great low end TQ as well.
I predict ~550-560HP @ 6000, and a high TQ curve down low, almost flat from 1500 on up.
TQ should be high, say 480-500#
16" vac at idle.
It's gonna be a blast!
Great combo!
Now decide on what hood you want.
BB intakes are very much hood dependent.
Great heads make the power. That's your best 1st choice.
Then you can keep the cam just a touch milder, at 224, vs 230, and have great low end TQ as well.
I predict ~550-560HP @ 6000, and a high TQ curve down low, almost flat from 1500 on up.
TQ should be high, say 480-500#
16" vac at idle.
It's gonna be a blast!
Great combo!
Now decide on what hood you want.
BB intakes are very much hood dependent.
Last edited by leigh1322; Sep 9, 2024 at 10:36 PM.
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Thanks for the confirmation. Looking forward to it especially if it hits those power estimates. Funny thing about the hood. One of the first things I looked into were good intakes. And I was immediately hit with fine print stating “Will not fit under stock corvette hood.” It’s been lingering in the back of my mind ever since. just one more hurdle to overcome!
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Helpful info! Thanks. I still have to figure out how to get even half the power to the ground too. I foresee lots of chassis work and of course, coilovers. Oh yeah, and a 5-speed and about 427 other items that I don't even know that I don't know.
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