L31 daily driver rebuild

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Orpedcrow

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I say stockish size will be the best for your 2wd road cruiser.
that's been my thinking too
PCM is going to limit the maximum torque of the 383 with torque management, but it will have a table top flat curve that peaks very early and holds until higher rpm.
that's good information, I didn't know our trucks had torque management. I do have a 411 to put in, I'm assuming it will do the same and that whoever I have tune it can mess with that.
You don't need a 4-bolt block. If you were towing or pushing 500 hp it would be worth the money. That 383 kit looks like a decent deal, but I'd call them and confirm what compression ratio you'd end up with. Are you planning on staying with the stock 64cc heads? Are you planning on decking the heads or block?
it is looking like a decent deal. I have ruled out the short block kit and will just get a rotating assembly. the nearly $400 in freight kind of negates the savings for me. now that you mention it, I guess I don't HAVE to deck the block if its flat (ill order a straight edge) I was planning on 64cc heads if mine are cracked or need to have a full valve job...
the one thing I regret in my latest 350 build was NOT going the 383 route
this seems to be the same sentiment amongst most SBC 350 people lol
as far as your transmission.... is it in relatively good shape? I can help you with a DIY shift kit that will extend the life of the trans if you are worried surviving behind.
it is in good shape, fluid is beautiful. its a GM Goodwrench that someone put in at an unknown milage. I know that "harder shifts" are supposed to be better for the transmission because it's not "slipping" the clutches as much? I think that's right. I do however really enjoy the feeling of NOT feeling a shift in my highway cruiser though :anitoof:
I did some research on building my 350 after I spun a rod bearing. I found a local machine shop who can do all the work (on my 2 bolt main block), including a full balancing. A Scat 383 kit and all of his work was going to be ~$4500 IIRC using my aluminum heads and cam. That's when I decided to go with Blue Print's new, 4 bolt main, "383" short block for $4712.53 with zero deck, 12cc pistons and 10.3:1 compression with my 62cc heads. I'm glad I went with it instead of staying with a 350 :33:

Now I have a 350 short block (and an almost new roller cam assembly) sitting under my bench waiting for some other project...
same here, its a $175 difference between having all my stock stuff machined vs buying the rotating assembly. plus my dad has a 68 c20 we can put this engine in later.
They fail to machine the valve cover rail correctly to allow the stock stamped steel valve covers to fit.
does this affect the center bolt covers too?
You don't need 4-bolt mains, you don't need a stroker kit, and you don't need aftermarket heads unless yours are cracked or severely wiped-out from wear. All you need is a fresh version of the engine you have already
sure this was my thinking also, but I figured a $175 difference for subjectively better parts seemed worth it to me :33:
I've heard that there are "two" Skip Whites, and one is good, the other is evil. But if that's true, why isn't the "good" Skip White suing the "bad" Skip White, or changing their name, or something?
the research I've done shows Skip White Performance is the original and White performance is next door and is the uncle or cousin of the original Skipe white or something like that but I don't know. as far as quality, unless they're reboxing communist garbage then its just about the same stuff I was looking at on summits website just less expensive and in kit form.
 

L31MaxExpress

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The cylinder head valve cover rail machining problem I described is only a stock stamped steel type centerbolt valve cover problem. The problem does not exist with most cast aluminum valve covers or perimiter bolt covers.

I also regret stopping at 383 cubes and not going for 415.
 

1998_K1500_Sub

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I also regret stopping at 383 cubes and not going for 415.

What's your recipe for a 415? Same as I might find on the WWW, e.g., stroked 400 block? Or a ~.060-over 350 block that's had the cylinder wall thickness checked?

What rod length?

I'm curious :popcorn:
 
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L31MaxExpress

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What's your recipe for a 415? Same as I might find on the WWW, e.g., stroked 400 block? Or a ~.060-over 350 block that's had the cylinder wall thickness checked?

What rod length?
My formula was going to be a Dart SHP 4.125 bore 350 main, 1 piece seal block with factory roller provisions. Then a 3.875" stroke and 6" rods.
 

Orpedcrow

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Am I under the correct assumption that some aftermarket parts are going to be better quality than factory parts? Apples to apples that is, not comparing full race forged parts.

Or is my assumption wrong that the $175 difference is worth it to replace everything vs having factory parts machined and reconditioned?
 

PlayingWithTBI

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Apples to apples that is, not comparing full race forged parts.
My example wasn't quite apples to apples. The Blue Print "383" short block came with the Comp Cam 08-432-8 (230/236 @0.050), lifters, timing set, and cover where, I was reusing the 08-430-8 (224/224) , and stuff (an additional $2000+ to convert to roller from flat tappet). The Blue Print made 436HP/443TQ with 1.6 rockers, their 195cc heads, and a 750CFM carb so, I figure I'm maybe closer to 400 with my 170cc heads but, I'm at 10.3:1 where theirs is 10:1. I know, my other cam won't do that and rev as high either. I'm happy with my set up now, you can tell it has a cam, idles at 850 RPM and ~70 MAP but, when cruising @~2200 and 60+ MPH, my MAP is down to ~45 and running smooth. I actually think it's quieter, and has less drone when cruising, than my 350 with the 08-430-8. As usual YMMV. ;)
 

tayto

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this seems to be the same sentiment amongst most SBC 350 people lol

it is in good shape, fluid is beautiful. its a GM Goodwrench that someone put in at an unknown milage. I know that "harder shifts" are supposed to be better for the transmission because it's not "slipping" the clutches as much? I think that's right. I do however really enjoy the feeling of NOT feeling a shift in my highway cruiser though :anitoof:
not to get too deep in the weeds but you don't want a hard shift, you want a QUICK shift. shift feel is subjective. i helped a member here set his unit up and it maybe 15-20% firmer than stock. you mostly won't notice it until you are WOT.
 

Schurkey

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Am I under the correct assumption that some aftermarket parts are going to be better quality than factory parts? Apples to apples that is, not comparing full race forged parts.

Or is my assumption wrong that the $175 difference is worth it to replace everything vs having factory parts machined and reconditioned?
Define "Better".

Aftermarket parts are ENORMOUSLY variable. Genuine OEM parts are tested, verified, generally-reliable.

Inexpensive "cast steel" (a TOTAL lie, Eagle has even admitted they've got too much carbon to be steel--they're CAST IRON) cranks, and inexpensive aftermarket rods get great advertising, but they're finished on high-speed machines that may or may not be in proper repair, using semi-skilled labor. Journal taper, journal roundness are questionable. Same for connecting rods. They may advertise super-steel, but is it CLEAN steel, or does it have impurities--contamination--within the grain structure? Is it, in fact, the grade of steel they're advertising? How would you know? Customers aren't going to submit one of their eight rods for testing. That "4340" steel could just as easily be 1015 steel, or 5140, or whatever grade was coming out of the furnace that day. The AIRCRAFT industry has been in trouble for cheap, contaminated steel in crankshafts, and they're watched like a hawk by the Feds.

And it's not like the Communist Collaborators in this country are going to do appropriate QA on those incoming parts. QA costs money, the whole reason for outsourcing is to cheapen the product and improve the profit margins. NOBODY goes to China to improve the product.
 
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Erik the Awful

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Or is my assumption wrong that the $175 difference is worth it to replace everything vs having factory parts machined and reconditioned?
What are you asking the machine shop to do, and how much are they charging? If you're asking for "the works", you're going to spend way too much money. Do as much as you can yourself. Clean and sonic check your crank yourself. Pop out all your core plugs yourself and just ask them vat, magnaflux, and bore the block. Only ask them to deck the block if it's not straight. Have them recondition the rods and install your oversize pistons.

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The factory rods are pretty good, even better than the famed "pink" rods. If you aren't spinning them to the moon and don't need 6" rods, stick with the stockers. Same for the crankshaft. For a street use motor, I'd stick with the stock pistons, but since you already need an overbore, you might as well bump up the compression ratio a bit. If you're not going wild, there are plenty of "good enough" piston sets out there under $200.

Aftermarket parts are ENORMOUSLY variable. Genuine OEM parts are tested, verified, generally-reliable.
I'm pretty sure Genuine OEM parts aren't tested mid-production by GM, other than via warranty returns. I'm also pretty sure GM isn't opening every pallet and sending one off to a lab for measurement. When I was a Nissan tech, Nissan's piston supplier dorked up and sent thousands of pistons with the wrong size marked on them. There were a couple of years of engines that developed piston slap and got replaced under warranty.

The AIRCRAFT industry has been in trouble for cheap, contaminated steel in crankshafts, and they're watched like a hawk by the Feds.
No, they're not. It's only "after the fact". You really don't want the FAA probing after your part fails, but up until it does there's pretty much no oversight. We have to trust that you haven't fraudulently filled out your paperwork.
 

BeXtreme

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No, they're not. It's only "after the fact". You really don't want the FAA probing after your part fails, but up until it does there's pretty much no oversight. We have to trust that you haven't fraudulently filled out your paperwork.
There is a significant amount of oversight. This includes inspections of the manufacturing facility and involvement from FAA personnel and FAA designees in both the design, testing, and approvals of parts for PMA and STC work for certificated aircraft applications.
https://www.faa.gov/aircraft/air_ce...e_prop/engine_approvals/engines_pma_approvals

There's a reason that an engine rebuild on a small aircraft can run you $50k, and it isn't the material cost. The certification work required and the level of quality control and inspections for the parts is not insubstantial.

I'm currently working on a PMA for a parts kit on one of my projects. It literally consists of two pieces of bent sheet aluminum, an electrical diode, three mil-spec circuit breakers, and a mil-spec relay. The part design and inspection work has probably consumed about 15 hours of engineering time. The compliance reports for the electrical certification aspects is probably another 5 hours. The compliance report for the flammability aspects is another 5 hours(plus both reports have to be reviewed and signed off by an FAA designee, in my case that is my boss since we have an organizational delegation from the FAA) plus the compliance report and sign off by the structural engineer and FAA structural unit member(probably another ~5 hours).

All of that is just to get the part approved to be added to the STC. Once it's added to the STC and the STC update is signed off, we then have to send a big bunch of documents off to our designated PMA guy who then spends at least a day processing and checking all of our work before he can issue a PMA letter. Once we get that letter we can then add a label to the part that designates it as PMA under that STC. Part of that is checking that the drawing we have for the parts and suppliers has enough detail in it to allow our incoming inspectors to make sure the part is not counterfeit and meets the specifications that the FAA delegates have determined is important.

The entire organization is audited by the FAA at least annually. We also have FAA personnel coming to the facility for meetings and tours randomly throughout the year for specific projects or for them to provide oversight as they decide they want to. Usually it is only if there is something particularly new or concerning to them being developed.

There was just a huge AD issued for continental engines for them shedding counterweights in flight. They had pre-emptively identified that there was a problem, what the problem was, and identified an inspection procedure and fix that was issued in a mandatory service bulletin before the FAA officially got involved. There is actually a process for this kind of thing and it starts with the manufacturer notifying the FAA that there is a problem and then keeping them apprised of the situation as its dealt with. Mistakes can be made by anyone, but the FAA can, and has in the past, revoked a manufacturers right to produce parts and get STC's. They can revoke an ODA at any point too if the manufacturer isn't doing the right thing. The end of the process usually has the FAA issuing an AD for whatever the issue ends up being.
https://www.aopa.org/news-and-media...continental-engine-issue-prompts-immediate-ad
 
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