looking for a cam power upgrade without problems

grumpyvette

grumpyvette

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hey grumpyvette?
I'm very new to the whole car/engine thing to be honest. Just started this summer. I have a mostly stock L81 corvette. The only thing not stock is a Holley 650 spread-bore carb and a distributor with a vacuum advance. My next step is to get a camshaft. What is safe for a stock converter for my transmission, TH350? Thanks.



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OK I looked up all the specs on your engine and corvette, and having that no potential future problems firmly in mind and still wanting you to feel a decent improvement in the engines power yet not wanting you to need to upgrade the converter, or rear gears or stock valve train....remember every change is a compromise in some area , but with experience you can make impressive gains without effecting your engines durability or drive-ability

the crower cam below is a good match, as it will work with all the stock clearances, components and your transmission stall and rear gearing, stock or upgraded,it should easily give you an additional 30 plus flywheel horsepower

http://www.crower.com/misc/cam_spec/cam ... 3&x=37&y=7

http://www.jegs.com/webapp/wcs/stores/s ... Term=00223

the lifters and cam quality selected are critical to long term durability, and while you can get lifters and cams that are far cheaper that the micro polished crower lifters ,and hardened cams they tend to be much softer and much more prone to wiping the cam lobes, you don,t want to be doing this twice or getting bits of worn cam lobes in the bearings when a cheap bargain cam wipes

Id suggest strongly you use the matched part #6600 CAM SAVER crower lifters, that have extra oil flow and a hardened and polished base and ID also sugest use of a 8oz tube of zddp paste with moly lube during the installation

http://www.jegs.com/i/Crower/258/66000X ... Id=1145259


http://www.jegs.com/i/Crower/258/86094/ ... Id=1145256

ID suggest a new timing chain set be installed with the new cam & lifters
http://www.jegs.com/i/Cloyes/220/9-1100/10002/-1
 
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Hello Experts,
I hope this is the right place to ask this question. I've got a stock zz4 350 with the Accel DFI Gen VII. Being stock, it has a "carb" camshaft. What is the difference between this and an "EFI" camshaft? Why is one better for EFI? Would I see appreciable perrformance or efficiency gain?

Thanks in Advance!


your carb cam timing is slightly different than the similar engine with the ideal EFI cam, but it won,t be a huge change as the cams LSA (LOBE SEPARATION ANGLE, DURATION and LIFT would be changed on an efi engine mostly to make the sensors for the efi read their data more clearly
keep in mind the cam was selected mostly for durability and reasonable power not to maximize performance.

heres your zz4 specs

10185071 Hydraulic Roller Tappet (ZZ4 Camshaft)
This hydraulic roller tappet is used on the 5.7-liter H.O. 350 ZZ3 & 4 engines. The duration at lash point in degrees (intake/exhaust) is 275/280; duration at .050” tappet lift (intake/exhaust) is 208/221; and maximum lift with 1.5:1 rocker ratio (intake/exhaust) is 474/501. Valve lash is zero/zero and lobe center-line is 112 degrees.

http://www.gmperformanceparts.com/E...=ZZ4350&engine=ZZ4+350&sku=12499712&engCat=sb


G.M. says youll get 40 more hp swapping to the HOT CAM

12480002 Hot Cam Kit (LT4)
This off-highway camshaft kit has the major valve train component to convert production LT1 engine for showroom stock racing, or hop up your small block Chevrolet V8 that was originally equipped with a roller tappet camshaft. The 1.6 roller rockers, light weight valve spring caps, special designed valve springs and hot camshaft offers a significant gain in horsepower at a reasonable price. This kit includes the following items: one camshaft P/N 24502586, 16 roller rocker arms kit P/N 12370839, 16 valve springs P/N 12551483, 16 valve caps P/N 10212808, 16 valve keys P/N 24503856, 16 valve spring shims P/N 10212809.
Technical Notes: This kit does not include roller tappets. If your engine already has roller lifters, you can use them with this kit, but always check for wear and replace if needed before installing this kit. If you are building an engine from a bare block, you can use the roller lifter kit P/N 12371042.
Special Note For ZZ4 Owners: This kit is worth 40HP more when installed in a ZZ4 which will boost the horsepower from 355 to 395, but the ZZ4 comes with the most of the LT4 HOT Cam Kit components already installed. The camshaft and lifters are all that are needed to complete the LT4 Hot Cam conversion on the ZZ4. The ZZ3 and prior versions of the ZZ4 will require the complete kit for the upgrade.




PROVIDED youve got a 3.73:1 rear gear and a manual transmission or a 3000rpm stall converter you can do better, but the drive train must match the much more aggressive cams operational rpm band, with its longer duration and youll need better springs with greater clearance to work correctly






you should read thru these links

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=82

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=181

example

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00470&x=51&y=9

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00471&x=51&y=9
 
that corvette or muscle car, youve purchased thats got an engine thats putting out less than impressive power levels doesn,t have to remain a boat anchor!
you can take your time, acquire the correct components and build a second engine while you continue to drive the car as it is, and once you've built a decent replacement engine a single weekend is required to do the swap out.
I can,t even remember all the times Ive build or helped guys build a warmed over second engine that we swapped in later and all the amazing grins I seen once the transformations completed.
the real secret here is careful planing and building exactly what you want, with matched parts, vs the far more common route of throwing together parts you find or get deals on, that seldom match as the funds allow and rarely getting a decent combo built.

spend a few days reading thru the links and sub links, and get a good grasp[ on the subject then post questions, building a really impressive SBC might take awhile but nearly anyone can do it if they chose too!

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=5078

http://forum.grumpysperformance.com/viewtopic.php?f=69&t=7722&p=26314&hilit=started+hobby#p26314

http://forum.grumpysperformance.com/viewtopic.php?f=69&t=3814

http://forum.grumpysperformance.com/viewtopic.php?f=44&t=38

http://forum.grumpysperformance.com/viewtopic.php?f=50&t=428

http://forum.grumpysperformance.com/viewtopic.php?f=87&t=339&p=21733&hilit=started+hobby#p21733

http://forum.grumpysperformance.com/viewtopic.php?f=87&t=4687&p=12679&hilit=started+hobby#p12679

http://forum.grumpysperformance.com/viewtopic.php?f=69&t=519&p=6077&hilit=+books+video#p6077

http://forum.grumpysperformance.com/viewtopic.php?f=50&t=46&p=55&hilit=+books+video#p55
 
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