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Discussion Starter #1
I plan on home porting my heads and intake on my 350 sbc. I have been told that i have picked out a bad cam for my setup (which is likely because i was like 17). I was wondering if anyone could give me a good suggestion for a flat tappet cam from summit.

I am running this setup in my 3rd gen camaro
-4 bolt 350 standard bore
-Eagle I beam rods rates for 500 HP
-Speedpro aluminum hypereutectic Flat top pistons
-906 vortec heads (Machining has been done to clear high lift)
-Summit cam (.480/.480 lift and 284/284 duration)
-Random headman shorty headers
-Summit stage 3 vortec intake
-650 Holley double pumper
-1.6 Lunati Voodoo full roller rockers
-1.250 inch comp cams springs 410 pound
-Ill be running a cowl induction hood too
-Torque converter is a 2800 stall and my posi has a 3.90 gear in the back.

Thanks for your help!
 

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consider looking at the Isky Z-20 or Z-25 solid flat tappet with pressurized followers.
consider a 750 cfm carb
consider real, long tube headers with 1 5/8 primaries
 

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More for Less Racer
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Sure, there are some better more modern cam grinds that will pick you up some, but you really aren't that bad off with your current choice. You might be able to swap to a better flat tappet cam and get 25 more horsepower, or going to a retro-fit hydraulic roller and pick up another 40hp, but to gain more than that you'll need more stall converter to be able to live with it, and it will need long tube headers.

What you've got right now isn't terrible at all.

With the ProForm HP main body upgrade you can turn your 650DP into a 750 for a real reasonable cost, as the 650, 700, 750, and 800 Double Pumpers all share a 1-11/16" throttle plate bore size baseplate. Keep your metering blocks and bowls, screws, etcetera, change the provided jets, and presto, you've got an adjustable air bleed, HP-bodied Holley 750 DP. Real nice, easy upgrade! :thumbup:

It will also probably like a 1" open spacer, or a Super Sucker style.

How serious are you about getting more power out of it??
Willing to rev it to near 6800-7000 rpm??
Willing to run a modern solid lifter cam??
 

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Discussion Starter #4
The Carb upgrade is an awesome suggestion I will have to look into that. I would like to maximize my hp but I'm not trying to spend big bucks on a roller setup. I have my limiter on my ignition box set to like 6800 rpm and she revs up there without effort. How does a solid lifter flat tappet setup change the way your engine runs? I mean if it makes good power I do not see why i couldn't go that route.

Oh and is this the type of upgrade you are referring to? https://www.summitracing.com/parts/pro-67100c/overview/
 

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yeah, that's the main body upgrade. :thumbup:

a solid lifter cam will pick up a bit of low end and midrange power, say 10-15 HP/20 ft.lbs TQ from 2500-2800 thru 4400, and then start gaining even more on up to a 30+hp gain at 6500 rpm.

A couple idea's for you:
Howards #110812-06 : 276/280° adv duration, 248/252° dur @.050", .535"/.540" lift w/1.5, .570"/.576" lift w/1.6 rockers, 106° lobe separation. This is listed as a tight lash(.014-.018") oval track cam but makes a great semi-serious street/strip cam 2500-6500 rpm range.

To compare this to what you have, if you take about 10° off the .050" duration of the solid cam, that would give you the equivalent hydraulic flat tappet. This is to account for the lash ramps on the solid cam lobes....so this cam would be fairly close to a 238/242° @.050" Hydraulic flat......so basically it would be about 10° bigger but a good bit more lift, which results in a lot more valve open area under the lift curve.
I've used a cam with this basic spec in several 350 and 383 street/strip/hotrod engines and it pulls really strong, has about a 1000 rpm idle, and pulls about 12-13" of vacuum.

I'd use a Direct Lube lifter also. They have a laser burned micro oil fed hole right in the lifter face to oil the lobe.
 

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Sure, there are some better more modern cam grinds that will pick you up some, but you really aren't that bad off with your current choice.
X 2... your combo isn't bad...

What are you using it for? Just performance Street cruising? Or racing where you want that last 20 HP?

Is your crankshaft cast or forged? If cast, you're prolly already pushing it RPMswise...
.
 
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