350 Specs

Ok, I've done a lot of talking, so here is what I'm actually looking at doing to this motor that I've started to build. I plan on re-using many of the internal parts but I don't know how advisable or even safe it is. My main concern is the price but if I'm going to blow this thing up the first time I turn it on I'll spend the money up front and won't think twice about it. This motor will be matched with a 700R4 with 3.73 gears at the back end. And before anyone goes off, I know I need to replace the bearings, piston rings etc..they are "no brainers" so I'm just listing the big stuff. I am doing some more research now on the parts I "want" should I just say screw it and go everything new...I'll post that when it's finished. Anyway, let me know what you all think.

--1996 Chevy 350 2-bolt main with factory roller cam (Should trade up or modify for 4-bolt?)
--Either use the crank that came with it or fork up $450.00 for a forged.
--Re-use the pistons, rods, and lifters (is this even advisable?)
--Edelbrock performer RPM intake (carburated, too much $$ involved for Multi or TPI).
--Rochester carb (stock 4bbl from 305, no clue as to CFM value but will have it rebuilt to spec if possible) or Edelbrock or Holly 650.
--Vortec heads modified for the extra lift the cam requires
--This cam...from Comp Cams or the one from Lunati listed after it

Camshaft Specification Table
Part Number 08-432-8
Engine -9999 Chevrolet
305ci-350ci
8cyl.
Grind Number CS XR282HR-10
Description
Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.51 0.52
Duration At 0.006 Tappet Lift 282 288
Valve Timing At 0.006
Open Close
Intake 35 67
Exhaust 78 30
These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 230 236
Lobe Lift 0.34 0.347
Lobe Separation 110


and Lunati's..

Advertised Duration IN/EX: 287/298
Duration @.050 IN/EX: 219/227
Gross Valve Lift IN/EX: .471"/.480"
Lobe Sep Angle / Intake Ctr Line: 112/108
Valve Lash IN/EX: Hyd/Hyd
RPM Range: 1800-5800


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my opinion?

never reuse lifters!!!!!

hardly ever reuse pistons, but i understand the cost savings if the bore is suitable for the stockers. (have block checked)

crank can be reused if the specs are within acceptable range, unless the performance numbers are going above 400hp. (have checked)

reuse intake

reuse Q-Jet (i personally love a Q-Jet)

if vortec heads check ok at machine shop go for it.

The roller lifters are fine to reuse, I`ve reused them several times and am about to do so again. Make sure you clean them up well and check the play in the roller bearings. The carb will likely be too lean being it came off a smogger 305, the primary will need tuned as will the secondary. If you use the cam you listed then you`ll need a power valve spring that`s weaker being the engine will pull a weaker vacuum signal. The stock pistons are also fine to reuse as long as there in good shape, and as long as the bore doesn`t have excessive wear. However keep in mind they are cast stockers, and they won`t hold up to continuous high rpm blasts. If it were me I would use the comp cams 215 duration @ .050 and .500 lift roller cam. We used this same cam in a friends car and it performs nicely and gives it a nice lopey idle. The first cam you listed would likely need a little more compression than the dish pistons can offer. The rods are also fine to reuse as long as there are no spun bearings. A tip I can give is to make sure you clean the he** out of the block after you hone it.

If you want a true 400 hp ( not desk top dyno or magazine hp) then there are a few things that need changed.

First get your self a set of flat top pistons. You will need to bore the block .030 over, unless it's a real low mileage engine. Also have it zero decked while it's at the machine shop. This will net you close to 10.0:1 static compression ratio with the vortec heads and a .041 gasket.....

Have the heads machined for you cam choice, and the correct springs installed. I personally would machine them for screw-in-studs and guide plates, and do away with the guided rockers, but they will also work. It's just my preference.

Then you will need a cam with the intake duration in the 230@.050 range. And 235@.050 for the exhaust....

With a good carb and ignition,headers this is a proven 400+ horsepower combo..

Keith

Ok, here is what I've been thinking of getting for some of those parts you say I should change...strait from Jegs or Summit racing. Should I go with Dome or Flat top pistons? Also, I will have the stock crank checked and if it's good and still within specs, then I will probably keep it, saves me almost $600.00. What I don't now is what bearings and rings to get. Anyone have any suggestions there? Now some say I should bore the engine anyway, which means I'll have to get new pistons anyway...is that the safest and most logical way to do this?

Camshaft --Hydraulic Roller Tappet, Advertised Duration 282/ 288, Lift .510/ .520, Chevy Small Block, Each
Competition Cams Xtreme Energy Camshafts Part number CCA-08-432-8 $245.88

Intake Manifold, Performer RPM Vortec, Dual Plane, Aluminum, Natural, Square Bore, Chevy, 302/ 327/ 350/ 400, ...
Edelbrock Performer RPM Vortec Intake Manifolds EDL-7116 $175.88

Keith Black Hypereutectic Pistons UEM-KB119-8 $220.69
Piston, Hypereutectic, Dome Top, 4.000 in. Bore, 5/ 64 in., 5/ 64 in., 3/ 16 in. Ring Grooves, Chevy, 350, Set

Or


UEM-KB120-8 $172.69 Piston, Hypereutectic, Flat Top, 4.000 in. Bore, 5/ 64 in., 5/ 64 in., 3/ 16 in. Ring Grooves, Chevy, 350, Set



Chevrolet 350 Forged 4340 Steel Crankshaft
356-435034805700 $589.99 "
3.480'' Stroke
5.700'' or Longer Rod Length
2.100'' Rod Journal
2-Piece Rear Seal (Early Style)
Internal Balance
1875 Bobweight
"


327-350ci 5.700'' Connecting Rods
356-SIR5700BBLW $259.99 327-400ci 5.700'' Connecting Rods
Large 2.100'' Crank Journal (2.100'')
Bushed Piston Pin
535-grams
Set of 8

Any reccomendations on the carb? And what headers will fit under a 84 Trans am? I can't run dual exaust because I don't have the room under the car for it so as I look at it, what's the point? Second, for a single exaust, how well does a 2.5inch single exaust compare to dual 2.5"? How would a 3" compare? Wow, once I start thinking about all the "other stuff" i need to do to go along with the engine it's going to be a huge project.