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350///357 build

38K views 156 replies 15 participants last post by  0trbo4myCHEVUICK 
#1 ·
Hello! I have started numerous threads in the past and have always been helped. Im hoping to return the favor to someone like me, in the future. (Even though you can find this build type countless times on countless sites all the frick over the place)

Going to try and post the best pictures as well as price throughout the whole thing.

First step is buying different pistons for my 1986 STOCK rebuilt short block.
Then looking for a roller cam, spider, bones, etc roller train components.

Probably going to use H345CP spreed pro pistons. Im shooting for 9:1 compression. I dont have them yet but I have 400 set back for a set of 64cc vortec heads.

I spent 425$ on the short block and 50$ on a gasket set.
 

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#83 ·
Well cool, just got off the phone with lunati. The man said the lt1/lt4 voodoo cams DO have the fuel pump lobe and the dowel pin is designed to be knocked back to proper length for a non lt1/lt4 OE roller block. So no grinding!

He also recommended timing set
Full Roller Timing Set - Chevrolet 262-400 (w/roller cam) 3 keyway - Lunati Power

Full Roller Timing Set - Chevrolet 262-400 (w/roller cam) 3 keyway
Product Description
Full roller timing set for Chevrolet 262-400 (w/ roller cam) applications
•Keyway(s): Three (+-4, 0)
•Roller Diameter: 0.250 in.
Part Number: 93026
Previoius Part Number: 93026LUN
Jobber Price: $70.27

He also stated the recommended valve springs for this cam are too weak. He couldn't say for sure about my springs without knowing the brand and type.
I gave him the spring specs I have and he said that they SOUND perfect for the application, but could not know for sure without further information.
Im going to run the springs I have.

I was also getting conflicting information on if the lift numbers were advertised with a 1.5 or 1.6 rocker. Some sites just say "factory rocker arm ratio" and some sites say with a 1.6 rocker.
He confirmed the lift numbers are with a 1.5 ratio rocker, which is a relief.

Gonna call scorpion next and try to talk rockers with them.
 
#85 ·
So if my heads have .040 milled off, and the block has not been decked. Do I simply subtract .040 off of the stock pushrod length? What other things are there that will effect required pushrod length?I know theres a tool and a procedure to check involving a sharpie and a solid lifter. I dont have either one of those three things lol.
 
#86 ·
You really cannot just subtract the amount milled to get the accuracy needed. Using published figures to calculate the p-rod length can also give inaccurate numbers. One good way to know for sure is to physically mock up the valve train to get the correct geometry. I like to do this with an adjustable pushrod (click on image for a short piece on making one).

Points to check
Geometry

 
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#88 · (Edited)
new pistons, resized rods, recon crank, new voodoo roller cam, new ls7 lifters, new valve springs, new valves, guideplates, reconditioned vortec heads with 59cc chambers, new pushrods(soon), new rockers(soon), new intake, new carb (Soon)

:thumbup:

Ive really been hoping to get a tech inspection on this build soon. I know he needs more info and in a more organized post as well. lol, I am aware the build and parts chosen are scattered throughout 7 pages of blabble and would never ask anyone to inspect the build in that fassion.

Im going to compile all of my information about this build including parts and measurments and everything else I can possibly think of into one clean organized post. Then hopefully the inspector will run through.

Im sure all the 350 builds get pretty old and boring for most of you guys, I def understand.
Doing live sound engineering for jazz music 5 or 6 nights a week gets old too me too! And audio is ONE of my top passions. Under the old school chevy of course!
 
#90 ·
............ Not sure what to think here.

I measured and I have 1/8"... Is that normal? I used what I had lol but I did replace the butter knife with several other straight edges in fear that the knife was not straight. I got the same measurements.
 

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#92 ·
stroke - 3.48
Bore - .040
rods - 5.7

heads - 906casting vortec heads milled to 59cc chambers. Never been used since built.
Heads have 1.94 Intake Valves, 1.5 Exhaust Valves
All Stainless Steel 1 piece Swirled Polished Competition Series Valves.
Custom 3 Angle Valve Job
Cut for Positive type Valve Seals installed.
Screw In Studs & Guide Plates were installed.
New Valve Springs and Retainers, Keepers
Springs are good for 600 Lift Cam.
Specs 135 lbs. @ 1.750, 325 lbs @ 1.200
Springs are 1.250 diameter
No port work has been done to heads.

compression - ?????

Carb - Dont have one yet, been looking at 650cfm double pumper holley's.

Intake - Vortec Edelbrock Performer RPM
Exhuast -1-5/8 Long tube headers. (dont own yet)
dual pipes with dual mufflers (Dont own yet)
Ill probably run the pipes all the way back or dump them by the rear tires on my regular bed 1982 silverado.(not short bed)

Camshaft - •
Voodoo Hyd Roller Cam - LT1 LT4 270/278 (20080721 or 60121)
Advertised Duration (Int/Exh): 270/278
•Duration @ .050 (Int/Exh): 221/229
•Gross Valve Lift (Int/Exh): .515/.530
•LSA/ICL: 112/106
•Valve Lash (Int/Exh): Hyd/Hyd
•RPM Range: 1800-5800
Voodoo Hyd Roller Cam - LT1 LT4 270/278 - Lunati Power

LS7 lifters, 1.5 scorpion platinum series roller rockers, skip white tall fabricated aluminum center bolt valve covers.
stock crank reconditioned
stock rods reconditioned

The block is a 2 bolt main...


the head gasket that came with it is stock.. I tried to measure it and its 1/32"...
 
#97 · (Edited)
#95 · (Edited)
I just wrote this reply on another thread, so I'll just copy and paste for you.....

Before you do anything, measure the piston deck clearance so I can compute your SCR. Here's how with cheap tools. All you need is a 6" or 12" steel rule and a set of feeler gauges. Bring any piston up to top dead center, stand the rule on edge about 1/4" from the edge of the bore (tallest part of the piston, right above the ring pack) at the 3 O'clock or 9 O'clock position as you are standing at the side of the short block. Trying to find the piston deck height with the steel rule placed at Noon or 6 O'clock will allow the piston to rock back and forth on its wrist pin and will give you false information. Stack feeler gauge blades together until you get a snug fit between the piston crown and the bottom of the rule. Hold the rule down firmly to the block deck, making absolutely certain that there is no air gap between the block deck and the bottom of the rule. Have a helper rock the crank back and forth a little clockwise and counter-clockwise to insure that the piston is at exact top dead center. Measure, re-measure and re-re-measure. I would do this on each corner of the deck, in other words on cylinders 1, 2, 7 and 8. In this way, you'll be able to find any discrepancy in the piston deck height, meaning that either the block needs to be cut to make the block decks parallel with the main bearing bore or one or more of the stack of parts (cylinder to cylinder) are not the same height. If the block decks are skewed (uphill/downhill) or not the same cylinder to cylinder, then the static compression ratio will be different from cylinder to cylinder. If you end up with an "on the edge" build with one or more cylinders making more cylinder pressure than the others, you could have detonation on those one or two cylinders while the rest of the cylinders are singing along happily. It's even possible that some of the pistons are 1.560" and some of them are 1.540". You have no idea until you measure the piston deck height as outlined above. With this simple procedure, you'll probably find that the corner to corner dimensions are off enough to make a problem. You can, of course, put the motor together without knowing any of this and it will run, but if you want the best performance from your build, you have to jump through some hoops.

My standard operating procedure includes align-honing or align-boring the main bearing bore, cutting the block decks to parallel with the main bearing bore, with the height of the deck being dependant on the stack of parts being used, along with the gasket dimensions and chamber volumes, then boring and honing the cylinders for new pistons that will work with my combination using torque plates, followed by a trial assembly where everything is measured before final assembly. That's how I do it. You can do it any way you wish or you can buy a crate motor and forget it.
 
#103 ·
Maybe a typo for 1/16" (0.0625")?

Anyway, the measurement need to be made at least w/feeler gauges between the quench band and the straight edge across the deck, spanning the bore. If you use a ruler, tip it up on its short edge, not laying flat where it can bow.

Below the piston is a true flat top. You would do the same thing except measure to the quench band of your piston:

 
#106 ·
The finest scale resolution is 1/64". So are you saying 5/64"? That would be 1/16" (4/64) plus 1/64 = 5/64". I hope it's not that, it would be a quench measurement of a whopping 0.078". Not good.

In any event, using a ruler like that is not accurate enough IMHO.

Edit I see you're getting feelers tomorrow. Good deal.
 
#110 ·
Technically the chamber volume includes the space between the deck the top of the top ring.In cases where you where right at the rag-get edge of a limit then that would be important. Some piston companies move the top ring down because of the application and heat issues.
 
#113 ·
And you jiggled the crank a little clockwise and counter-clockwise to make certain that the piston is at TDC, right? And no air gap under the rule at the block deck, right?

OK, now it'll be interesting to see what the other 3 corners look like.:eek:

This is one of the cornerstones of having a good build and not having a good build. The more information you can put together about various pieces in the motor, the better your choices will be for parts that contribute to the combination.
 
#114 ·
might catch hell for even mentioning this, but IMO you can figure deck height fairly accurately with a dial caliper. when i originally assembled my engine(350 sbc) i borrowed a friends deck bridge and indicator to check mine. They were found to be .010-.011 in the hole.. the other day just for curiousity i had a degree wheel on and rotated it to bdc. Using the leg on my caliper i measured from the deck surface to the piston edge inline with the wrist pin. 3.491"... - 3.48" stroke = .011" ...thats close enough for gasket selection purposes. Beware if you tried this method at TDC the chamfers would ruin any hope for accuracy..
 
#115 ·
Beware if you tried this method at TDC the chamfers would ruin any hope for accuracy..
As I say often, this stuff ain't rocket surgery :eek:
All you would need to get a very accurate measurement at TDC is a small framing square. Maybe I'm saying it wrong, but it's the flat measuring rule that is shaped like an L. Sit one side of the square down on the deck and butt the side of the dial caliper up against the other side of the square and measure with the slider on the caliper. There's room at the tip of the caliper to make contact with the deck and also to reach the crown of the piston with the slider part of the caliper.
 
#116 ·
After rocking the crank/piston to establish that you're at TDC, tap the top of the piston to seat the bearing against the crank journal. It won't make much difference (not more than ~ 0.002"), but it helps w/accuracy if you're measuring the all four corners to get a rough estimate of what the decks look like for being square.
 
#118 ·
Well, it wouldn't be good news, that's for sure. Getting a decent quench w/that much piston deck height isn't going to happen, not as things currently stand.

You have the option of one or more:

• shaving the decks
• using a taller compression height piston. If you have rebuilder pistons w/a 1.54 CH, that can gain you 0.020" (piston closer to deck)
• thinner head gaskets. The thinnest are 0.015" steel shims, they need a flat surface on both sides to seal to. The finish is important, too. That usually means a clean-up skim off the decks and heads for best results.
• You also could build it w/a less-than-perfect quench. Using a thin composite gasket (0.026-0.028") and your pistons you'd end up with about 0.065" quench. Definitely not ideal but I've seen worse. Not saying to do this, just saying.
 
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