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I guess that’s one way to wash the bore.
 

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1998 LS AWD Forest Green metallic
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That could turn out to be a nasty mess, or it could become a good rebuilder. I hope it comes apart ok.
IT will be fun to watch progress, if you allow us to follow along.
Rod J
Issaquah, WA
 

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Discussion Starter · #7 ·
That could turn out to be a nasty mess, or it could become a good rebuilder. I hope it comes apart ok.
IT will be fun to watch progress, if you allow us to follow along.
Rod J
Issaquah, WA
.030" overbore should solve everything. If not, then .060" will surely take care of it. I probably would have bored anyway.
 

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have the head shaved a tiny bit too, bump the compression ratio a tiny bit won't hurt the computer as long as you keep it at or below 9,5 to 1.
 

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Discussion Starter · #9 ·
have the head shaved a tiny bit too, bump the compression ratio a tiny bit won't hurt the computer as long as you keep it at or below 9,5 to 1.
Computer? Where we're going, we don't NEED computers. ;)

This is my first entry into SBC land, so I don't know that this is a universal thing, but my understanding is that GM put the pistons something like .005" down the hole at TDC. If that is true, the first thing to address is that. The engine is around 9.5:1 stock with a stock 64cc combustion chamber, so I don't think I have far to go before I have more compression than I want.

CR is a small contributor to horsepower anyway, so I'm not going nuts there. The main reason to have lots of compression is to make better use of a wild cam, which is something I can't afford to do on a family hauler with AC.
 

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2000 Lifted 4x4 Astro 92 V8-350 Shorty
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Yes... high compression, high rpm horsepower, wild cams... not ideal for a family hauler.
In fact.. a mild cam will yield possibly more low-midrange torque.. necessary to accelerate and move a van in it's normal operating range.

I have way too much cam in my 92 V8-350, and I often wish I had something a little more moderate. Not to mention how ridiculous it can be idling at a light while in gear while trying to run A/C.. with a rough choppy idle jumping all over the place. I have to chose between idling in-gear or A/C on, but never both. Even a practical higher stall converter can only do so much. Looks good and sounds cool though. But that's the phase I was in 20+ years ago, and this one caught me a little off guard. None the less, it's mostly a weekend cruiser, and it actually does quite well with fuel on the highway, despite being a little excessive.

As far as computers... I cut out a lot of wiring when I removed my computer permanently.. and have never looked back. I literally have 1 switched 12v wire to the HEI distributor to run the entire engine.. that's it. When I turn the key.. it's always 100% ready to go!

Regarding piston depth.. I utilized my first thin steel gaskets to maximize "combustion squish" effect.. something new to me that I never considered in the past. The results were excellent.

I hope that rust in you cylinders didn't ruin the bores.
Good luck
 

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Discussion Starter · #11 ·
Yes... high compression, high rpm horsepower, wild cams... not ideal for a family hauler.
In fact.. a mild cam will yield possibly more low-midrange torque.. necessary to accelerate and move a van in it's normal operating range.
Indeed. I have no intention of going there. I will keep LSA above 112 degrees and limit myself to about 220 degrees of duration at .050" lift. The problem--opposite of what I am used to dealing with--is choosing ONE cam out of many that fit those parameters. I am used to having one cam to choose at best, and now I am overrun with selection.

As far as computers... I cut out a lot of wiring when I removed my computer permanently.. and have never looked back. I literally have 1 switched 12v wire to the HEI distributor to run the entire engine.. that's it. When I turn the key.. it's always 100% ready to go!
For this one, at least to begin, I don't want to lose sight of the shore. So I'm going to protect the connectors with some dielectric grease and tuck them away in case I want to go back to the TBI V6, or just TBI.

I hope that rust in you cylinders didn't ruin the bores.
So do I! Really, I don't think it will be that bad. Certainly it will need a bore, but I think .030" will take care of it. Worst case is that it will take .060".
 

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Discussion Starter · #12 ·
I finally got the V8 engine torn down. Once I got the pistons out of the two rusted cylinders, the cylinders didn't look so bad anymore. I think a .030" overbore will do the trick. Of course, I'm not buying pistons until the final bore size is known. There were no other signs of trouble during the teardown. The engine is now ready to go to the engine builder.

I had to tear the engine down completely so that I could manage its weight by myself and load it into the Toyota Matrix that I will be using to haul it to the machine shop.

After a discussion with the engine builder, the basic parameters of the engine are set: ported heads, upsized stainless valves, mild springs, roller rockers, keeping pressed studs, mild cam. He is trying to revive my interest in FI, but I am still skeptical about the long term durability of aftermarket FI on a vehicle that is going to haul my wife and child all around the country.
 

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2000 Lifted 4x4 Astro 92 V8-350 Shorty
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A friend of mine (in his high-end classic custom show Camaro) spent the past year enduring a nightmare with 2 aftermarket FI units.. both FAILED and left him on side of road getting tow home each time. Despite professional engine builder installation, the product itself failed. When the 2nd unit failed (which he bought directly from FiTech).. they told him it would be 6-8 weeks to replace the defective unit. They offered NO solution when he asked what he was supposed to do for the next 2 months.

He purchased a NEW Holley carb.. and couldn't be happier (originally had a Holley that worked fine). He says it runs perfect, and no more worries when things might suddenly just stop working.

This is a guy with money.. but unfortunately still had horrible luck with this product. He lost much of the year with his car out of commission, or in and out of shops, all because he thought FI would be a smart upgrade. He calls it a nightmare that he will never repeat again.

Not 1, but 2 failed units.
He's done with that unreliable product.

I had started considering the aftermarket FI option (for my 2000 when I finally upgrade my engine).. but have now completely ruled out that idea. Factory FI is more reliable (although there are countless posts on this forum with endless issues).. so I've decided I will also stick with carburetion. It works great in my 92.. just turn key and it always starts. Carburetion has worked fantastic for me for decades and reliability is my most important concern. That and there are NO sensors, wiring, or controllers to go bad... ever.

I also don't have to deal with emissions issues where I live, and a carb can be tuned to run nice and clean too.

But that's me. I'm old school, and like things simple and working.
Not everyone has issues with FI.. and when it works it's great.
But it's just not for me. I find a fresh carb the easiest, mort reliable, and best!
Great gas mileage too.

Which ever route you choose... best of luck!
 

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2004 Astro AWD, 2004 Safari 2WD
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I think you paint it rosier than reality...
but I agree.
 

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Common Sense + Critical Thinking
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Of course you don't have to go aftermarket either, always can keep it rock solid OEM and still have the benefits of FI. All going to depend on what you want to do.
 

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Discussion Starter · #16 ·
A friend of mine (in his high-end classic custom show Camaro) spent the past year enduring a nightmare with 2 aftermarket FI units.. both FAILED and left him on side of road getting tow home each time. Despite professional engine builder installation, the product itself failed. When the 2nd unit failed (which he bought directly from FiTech).. they told him it would be 6-8 weeks to replace the defective unit. They offered NO solution when he asked what he was supposed to do for the next 2 months.
Right, and this isn't a show car or a toy that costs me an afternoon if it breaks down. This is the family truckster that is going to see long road trip use with wife and baby inside almost every mile. It MUST MUST MUST be reliable--at least as reliable as a factory vehicle in a good state of tune.

The EFI unit that I still consider is the Edelbrock Pro Flo because it is a conventional port injection system. The Holley and FITech systems with the ECU inside the TB unit are just asking for trouble. Maybe they make sense for the show car/toy that needs a super clean carb-like install, but they don't make sense to me. Keep the computers off the vibraty hot things. With that said, while I do still consider it, I am half afraid of it from a durability/reliability standpoint. A carb install is certainly easier and simpler, and a correctly tuned carb is as reliable as anything.

I, too, don't have to deal with emissions checks--yet. Time still remains for me to decide on fueling. It might well end up with a carburetor on top.
 

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Discussion Starter · #17 ·
Of course you don't have to go aftermarket either, always can keep it rock solid OEM and still have the benefits of FI. All going to depend on what you want to do.
That is also true. The factory TBI has probably millions of dollars of engineering and testing behind it with drivability engineers nitpicking it to death before it was released, and the aftermarket systems probably have thousands of dollars of engineering and testing, with maybe not much more than a wet thumb in the wind to reliability and drivability.

I don't want to go through the effort of a swap and the cost of a rebuild for OE TBI V8 power. The TBI system can be tuned and tinkered to make some more power, but it is always going to be the limiting factor in making power. The TBI unit can be bored and fitted with larger injectors and the pressure can be increased, but it's still pushing it really hard to make more than 350HP, and I would like to see 400. Plus, modifying the TBI system for power could bring in reliability issues. I mean, I would have to double (or better) the factory fuel pressure to get where I need to go.

Some thoughts have passed through my mind to build an intake manifold with dual TBI units to prevent each one from having to work so hard. But that is a stupid idea that I shouldn't even mention.

Sometimes I do think to settle for 250-300HP and keep the TBI, but I hate to give up 100-150 horsepower because of one component, especially since the rest of the build would cost almost the same regardless of power.
 

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I wasn't saying TBI, though a single ported TBI could be used for 600+cfm/400hp. Holley has a 670cfm version Holley 502-9: Replacement 670 cfm TBI 1990-95 GM 5.7L V8 truck - JEGS High Performance so it's definitely possible. I would be thinking more along the lines of the L31 FI with a 0411 computer that you can tune using free software.

Of course if you don't like the stock intake, Holley makes one with fuel injection bungs and fuel rails. Holley 300-263 Holley EFI Intake Manifolds | Summit Racing using EV1/EV6 injectors. Marine intake is available as well as adding ports to the aluminum Edelbrock intake.

Plenty of options for that engine, that is for sure.
 

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Discussion Starter · #19 ·
I wasn't saying TBI, though a single ported TBI could be used for 600+cfm/400hp. Holley has a 670cfm version Holley 502-9: Replacement 670 cfm TBI 1990-95 GM 5.7L V8 truck - JEGS High Performance so it's definitely possible.
I wasn't picking up on that. Yes, flowing the air through the TB isn't as much an issue as flowing the fuel through the injectors.

I would be thinking more along the lines of the L31 FI with a 0411 computer that you can tune using free software.
Everything that you have said is unfamiliar to me. Judging from some quick googling, it seems that the 0411 ECU is for a Gen III engine. This is somehow being used on the CPI (L31) harness, with the addition of wires for pulsed injectors? I have wondered about swapping complete engine management from a Gen III engine since it is so hackable, but I know nothing about what you are suggesting. Excuse me if I am way off, but I don't know what I don't know.
 

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I wasn't picking up on that. Yes, flowing the air through the TB isn't as much an issue as flowing the fuel through the injectors.

Everything that you have said is unfamiliar to me. Judging from some quick googling, it seems that the 0411 ECU is for a Gen III engine. This is somehow being used on the CPI (L31) harness, with the addition of wires for pulsed injectors? I have wondered about swapping complete engine management from a Gen III engine since it is so hackable, but I know nothing about what you are suggesting. Excuse me if I am way off, but I don't know what I don't know.
The 0411 PCM was used with a bunch of engines which makes it extremely popular, like a lot of engines/configs, 4.3/5.0/5.7/4.8/5.3/6.0/etc. So you could grab whatever you don't have, like the intake/injectors/wiring harness/PCM etc from the junkyard, for example an 01-03 Express, trucks had them, camaros, vettes had them. That would give you a complete factory proven SCPI/MPFI setup for your engine. Then you can use PCM Hammer and Tunerpro with a cheap adapter to adjust the tuning to your modifications without having to spend a dime on software/vin licensing/etc.
 
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