Could you all help me with an engine build?
Id like to make a mild street/strip build out of a 4-Bolt 350 #207 Cast. SBC block i've picked up, I dont know all that much about how each component pushes and pulls with another, and more likely than not what I came up with may be the worst thing you all have laid your eyes upon, but id appreciate any input on what I can do better.

Oh, and shoutout to sofakingdom for helping me find a compatible block, if you're reading this,

Specs:
383 CI
4.030" Bore
3.75" Stroke
5.7" Rod Length
9.5:1 CR
- 18 CC Dish Piston
- 64 CC Head
- .041" Compressed Head Gasket w/ 4.166" Bore
- .005" Deck Clearance
8.4:1 DCR
HEI Dist. w/ CC
750 CFM Rebuilt Quadrajet
Edelbrock Performer Intake Manifold #3701
TrickFlow Super 23 195CC Cylinder Heads
- 2.02" Int./1.6" Exh. Valve Diameter
- 195CC Int./75CC Exh. Runners
1 5/8" Headers -> 3" i.d. Single Exhaust
Crower 288H Hydraulic Flat Tappet
- 214/224 @ 0.05"
- .444/.464 Valve Lift w/ 1.5 Rockers (I likely will end up using 1.6 RR so .474/.494)
- 112 LSA
700R4 Tranny
- Rebuilt w/ way too many parts to list, far more then a TransGo shift kit, it'll hold up (hopefully)
- 2400 Stall Converter
7.5" Rear End
- As is, stock but I plan to beef it up substantially to stand up to the torque as I know these are always the first thing to go from reading
- 3.73 Gears
- 25.7"-ish Tall Tires (275/40R17)

I dont want a crazy speed-demon running <12 seconds at a 1/4 mile, just something reliable and torquey, thanks for reading!

 

I think you'll get exactly what you want out of that combo.

I have a cam about that size in my 383n 3.42 axle ratio, and 2500 rpm converter and it is an absolute blast. But it also has a smooth idle and very pleasant manners.

The heads might be a tad to big though... you might want to err closer to 180-190cc since the cam isn't that big.

 

Glad to be useful.

First thing I'd recommend is, make sure however you build it, select parts that make it INTERNALLY balanced. It might cost a bit more up front, but will save you untold grief, confusion, pain, and expense over the life of the engine. It's mostly a property of the crank: the rods must be long enough, and the pistons short enough, to allow the crank counterweights, which are "at TDC" when the pistons next to them are at BDC, to be large enough to completely counterbalance the other parts. 5.7" rods are long enough to allow this if the pistons are properly set up for it. A ring package that has narrower and/or more closely spaced rings may be necessary, so if you see pistons with 5/64" compression and 3/16" oil rings, they're possibly not capable of this. Usually you can buy all of those parts as a "kit" with the right dimensions.

Second thing is, with that CID, 64cc heads, .045" deck clearance, and those piston specs, the compression is about 8.8. Deck clearance is how far below the deck the pistons are at TDC. The factory "spec" for this is about .025" (pistons are that far "down in the hole" at TDC); although they fail to mention that they allow variations from cyl to cyl, often as much as .015", depending on how accurate the crank is machined, how well matched the rods and pistons are to each other, and most of all, how sloppy the deck machine process is. Often the deck height is substantially different from left bank to right, or front to rear on one side or both. Sometimes the crank tunnel isn't straight which produces the same effect on both sides. Worse yet. NEARLY ALL cast pistons, MOST hypereutectics, and QUITE A FEW forged ones particularly most TRW/SpeedPro, add an extra .020" of deck clearance, so that "rebuilders" who are working on blocks with destroyed decks (from blown head gaskets mostly) can use them even if they have to heavily deck the block. Aftermarket cranks and rods, and pistons for 383 which are more a "performance" than a "rebuilder" item, tend to have these problems FAR LESS than "rebuilder" parts, but it still needs to be verified. FYI the order in which a factory block is machined is, oil pan surface first (those 2 giant holes on the side opposite the oil filter that don't seem to have any purpose are the gauge holes for the whole process), then the crank and cam tunnels, then the decks. You can have your block trued up at the machine shop by first having the crank align-bored (or merely align-honed, if it's within the limits of that process) to perfect the crank location, then have it decked to set the decks perfectly parallel to the crank, perpendicular to each other, and at the correct height. Deck height "spec" from the factory for all SBCs is 9.025"; likewise, the "spec" for the height of the rot assy is 9.000" (½ the stroke, plus the rod length, plus the piston pin height). In your 383, those #s would be 1.875" for ½ the stroke, 5.7" for the rods, and 1.425" for piston pin height (distance from pin center to flat of the top of it). When getting it decked you can even "zero deck" it, i.e. distance from the crank centerline to the deck of 9.000", which will make your pistons come exactly flush to the top of the block at TDC. In that case, the CR will be about 9.6:1.

Note that you can't "take off .xxx" " to get this right, because the dimension you start with is SO RANDOM. You have to measure from the crank CL, NOT from wherever the deck is NOW. If the machine shop says "we'll take off .030" or whatever, tell them NO, that's NOT what you want; you want HOWEVER MUCH IT TAKES removed, to bring the height from crank CL to deck, to exactly what you want it to be. This will usually require a racing shop; yerbasic corner parts store machine shop generally won't have the tooling or expertise to do this.

Another thing to watch out for is the perpendicularity of the bores to the crank. The factory is notoriously sloppy about this as well. I've had motors where people brought me blocks, and the bores were tilted SO FAR front to rear, that the rods would bind on their sides. Have your block bored & honed with a deck plate, and instead of boring it "on the wear" as they usually do, have them locate the bores PERFECTLY where they belong. That is, perfectly perpendicular to each other L to R bank, perfectly centered on and pointed at the crank journals, and perfectly perpendicular to the crank CL. The deck plate will assure that the bores are as nearly a perfect circle as possible WHEN ASSEMBLED; a block distorts a surprising amount from the stress of the head bolts, causing all sorts of lumps and dips down the sides, and machining it while it's under that stress means the bores might be weird with no heads (when it doesn't matter), but when the heads are bolted up, they'll be straight.

Another detail I've seen make motors go sideways is, the oil passages from front to rear, which are those 3 holes around the cam tunnel. The ones to the sides of the tunnel feed the lifters, and the one above it feeds the bearings. They're supposed to be ½" diameter all the way through. Problem is, they're drilled with one drill halfway through from the front and another halfway from the rear; like building a bridge from both sides of a river, they're supposed to exactly meet at the center. I've seen blocks where they missed each other by so much that a ¼" rod couldn't be inserted all the way through (made it hard to knock the welch plugs out of the front of the passages). Needless to say, this will SEVERLY restrict oil flow to the front of the motor, and lead to main & rod bearing problems, or lifters with "mystery tick" that you can't fix no matter what you try. Have yours looked at and corrected if not perfect. Have the front plug holes tapped for ¼" pipe plugs; use brass ones with Allen drive, and drill a hole in the centers of the 2 to the sides of the cam, with about a #75 to #70 (around .020" to .028" or so) drill, to oil the timing chain.

Use a Melling IS-55E oil pump drive rod, which has a metal sleeve holding it to the pump, instead of the little nylon one. The plastic kind can break, although not often; I've had one that did, and it's NO FUN at all. Fortunately in that case the driver saw the oil pressure go away and shut it off soon enough that the bearings survived, but fixing it was a PITA of course.

All of these things are part of what people like to call "blueprinting" the motor. That's shorthand for making it PERFECTLY (or as nearly so as practical) match the specs, taking ALL of the tolerances and variations and imperfections out, as much as possible, or at least practical at some manageable level of $$$. This is the kind of thing that explains why some motors run SO MUCH BETTER than others, even when built out of the exact same part numbers. There are some tolerances you can't really take out unless you REALLY spend BIG $$$, and are just stuck with, such as lifter bore alignment to the cam lobes, head and bell housing dowel pin location accuracy (although for the BH ones you can get offset pins if the pattern is so far off-center from the crank CL that it needs correction), starter bolt hole location accuracy, and so on. While it's "possible" to fix alot of these errors if they exist, it's usually cheeeeeeeper to just scrap the block and get another if they're found, which they should be checked for before sinking too much machine work cost into it. It SUCKS to throw a complete block machining job in the trash, which YOU will have to pay for, since after all it's YOUR block, and it isn't the machine shop's fault if YOU brought them one that's too fornicated in some way to be used. Fortunately by the 80s when that block was made, the factory had cleaned up some of the worst of their sloppiness in the engine plants, but they're still prone to error and need to be checked.

 

Or can just get a HT383 short block from GM like i did. Already set up for a roller cam too. It's a fantastic foundation for building up a 383.

 

I planned on using Eagles B13054E030 Rotating Assembly, its internally balanced and the piston pin height is 1.433" which would give me around 9.008" deck height (I had no idea about that formula up until now, thanks! ), but the piston ring pack provided is 5/64", 5/64", 3/16", is it better to piece together a rotating assembly by scratch or would you still recommend going through with what Eagle provides and just buying a narrower ring pack to replace it?

Secondly, and more importantly,
I've just gotten into rebuilding my Trans Am I picked up not too long ago, all of the know-how and advice you've provided has been priceless to helping me get my bird on the road, thanks for all the help.

 

Ill definitely consider it, once I finally get around to the final cost of a prebuilt short block vs. a rebuilt short block i'll make my decision then.

 

If they say it's internally balanced, then go for it. Problem with the wider rings would be, if you were trying to piece together something, that would be a likely (though by no means absolute) indicator that they might not work. In this case they may have merely spaced them more tightly and/or moved them up slightly closer to the crown of the piston to get them to fit.

Who's doing your machine work? A racing shop? If not, I suggest NOT using them, but instead, find a specialist. It'll cost more, maybe you'll have to wait behind their regulars, butt DEFINITELY be worth it. If you don't know any, go to a circle track in your area, on a night they're running sprint cars or the like so that people who are hard-core and maybe even semi-pro are entered (not the "bomber" classes or that sort of thing, where you'll mostly be seeing rank amateurs); buy pit passes; hang out in the pits and talk to the guys THAT WIN, or at least whose motors last the whole race; find out who they use for their machine work; and go there. It's worth EVERY PENNY and then some. Back when I built motors, I used machinists of that sort, one in particular, and I always got referrals for building them from the semi-pro kind of guys, because everybody knows you CANNOT win a race with a motor, butt you SURE AS HELL can LOSE one. My motors got a reputation for finishing more races than most, lasting more races than most others (however many or few the particular class abused them to), and tending to be toward the front because they weren't down a cylinder or the rev limiter had to be set too low to keep them from blowing up. You want THAT KIND of motor. One of my most serious and competent competitors used to paint his blocks the most garish fingernail-polish color of metallic pinkish-purple you can think of, so that ONE GLANCE was all it took to know that it was HIS motor, kinda exactly like a sponsorship sticker; and if you repainted it, he'd never build you another. It's an interesting business.

 

Problem with a GM short block incidentally, is that they're prone to EXACTLY the same kind of tolerances and variations and uncertainties and whatnot, as new-vehicle ones. Uncontrolled production-line deck height for example. Not as extreme as mass-produced passenger car or light truck motors maybe; maybe for their "performance" products they take a bit more care than that; butt they're still not built with ANYWHERE NEAR the kind of individual attention to EVERY measurement, that can potentially be devoted to it. OTOH they do have the MAJOR advantage of a warranty, if not opened up, as well as being new (no need to worry about a history of overheating or metal shavings in the oil passages from previous blow-ups, for example). You get a FAR better product than most "rebuilds", butt NOWHERE NEAR what a genuine race shop can do. Price will probably end up about the same as what I"m descibing to you; no big advantage one way or the other there.

 

Fair. But I think for the vast majority of people it's probably more than adequate.

 

So I got a good bit of questions I recently started on a engine and it’s a 350 with a 0.040 bore on it with a eagle crank and stock pistons I’m trying to build it street /strip motor and I have a couple ideas of cans to put in it like the comp cans extreme energy cams or the ***** thumpr cam from comp cams just wondering what yall would think to put in it to use .

 

Im certainly no expert, but I think the general consensus is to steer clear of Comp Cams...

The price is certainly appealing, but after reading countless forums and posts trying to figure out what I wanted out of my engine I rarely or never found any complaints about destroyed cams/lifters from Isky, Crower, Schneider and so on but dozens when a Comp Cam is involved.

Could just be user error though due to their accessibility... hard to say.

 

Well I appreciate that cause I was seeing a lot of stuff about comp cans and I did not know really but I do appreciate it