Thread: 89 305 to older 350?

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i have an 89 caprice classic brougham with the original efi 305. i'm interested in a 350 swap and i'm not sure which year i'm going to end up with at this moment. i'm going back to carb for now and i'm wondering if i'll be able to use the accessories from this 305 on a 70s~ 350 sbc and if i'd need to change any wiring that'd be difficult for a novice.

also, we have a 350 on hand but it's a bit beat. how much would it cost/what steps could i take to have it inspected? should i just buy a new one that we know is running and driving?

i ask about the accessories because most motors come without them. maybe you all know something i don't, but they seem pretty hard to find. (water pump, ac, etc.)

Does this 1989 Caprice Classic Brougham have a special sentimental value to you? I'm not sure I'd be investing too much in the vehicle unless it's got a very special story. Even with a sentimental tie I'd be looking at a basic "crate engine" to drop in, like visiting your local O'Reilly's, Pep Boys or other big box auto parts store to get the cheapest basic 350 with a warranty. Check Summit too, and use the beat 350 you have for the core, and be done with it.

Originally Posted by rspears

Does this 1989 Caprice Classic Brougham have a special sentimental value to you? I'm not sure I'd be investing too much in the vehicle unless it's got a very special story. Even with a sentimental tie I'd be looking at a basic "crate engine" to drop in, like visiting your local O'Reilly's, Pep Boys or other big box auto parts store to get the cheapest basic 350 with a warranty. Check Summit too, and use the beat 350 you have for the core, and be done with it.

this specific car isn't special to me, no. i actually wanted the LS trim instead, but i can wait for that. i love these box chevys and wanted to start somewhere. i just want to put a better motor in for now since this 305 is almost trash. the car itself is a good base for a project. i'll probably go lt1 out of a bubble later on since i don't want to keep this one stock. i just want to cruise for now. the extra power would be nice as well.

Originally Posted by Sad Dad

this specific car isn't special to me, no. i actually wanted the LS trim instead, but i can wait for that. i love these box chevys and wanted to start somewhere. i just want to put a better motor in for now since this 305 is almost trash. the car itself is a good base for a project. i'll probably go lt1 out of a bubble later on since i don't want to keep this one stock. i just want to cruise for now. the extra power would be nice as well.

Shop for a nice crate engine from Summit or a similar source that you like. You'll spend twice as much rebuilding the 350 you've got, and the crate will have a warranty. Just my $0.02 on the options. Best of luck on your project.

Originally Posted by rspears

Shop for a nice crate engine from Summit or a similar source that you like. You'll spend twice as much rebuilding the 350 you've got, and the crate will have a warranty. Just my $0.02 on the options. Best of luck on your project.

that's good advice, so thank you. i'm a kid, so i was going to look for a used sbc to save some money for now. do you think the extra thousand or so is worth? i know this is pretty self explanatory, but may as well ask. also, since the crates are usually bare, should i look for a specific one to fit this 89 305 water pump and other accessories on? those pulley kits are pretty expensive

Log on to Summit Racing and check out what they offer - short block, long block, or complete with accessories depending on your budget. You might want to visit your local auto parts guys too, just for options.

Welcome to CHR!

All of the accessories will bolt up from the 305 to the 350, AC, alternator, power steering pump, water pump, pulleys, etc. I'd invest in a new water pump simply because the one on the 305 is 31 years old. The alternator may be a good one to swap out as well as new belts and hoses.

Carefully clean and label everything as you disassemble - take lots of pictures and write everything down. Make sure you disconnect the battery and remove it before you begin removing the accessories as a quick short to ground can make a real mess of wiring that's a pain to replace.

You'll need a different manifold for the 350 - not due to size - but to go back to a carburetor. I'd recommend a Weiand spreadbore manifold and a fairly stock 750 Quadrajet (Summit Racing is a good source).

I'm assuming you have access to a garage, an engine hoist (you can rent one as well) and a good engine stand.

Assemble all your parts, ask us lots of questions and you'll be just fine.

Let us know how you decide,
Glenn

Good advice from Roger. A basic crate engine can often be more cost effective than trying to build or rebuild the engine yourself. Check prices both ways. However, if you've never been into building engines, there is a lot to learn; it may be wise for you to find a friend or family member who has done it before and is willing to "walk you through it" the first time.

One thing that is helpful - small-block Chevy engines are all dimensionally the same on the outside. All the pulleys, brackets, and accessories from your 305 should bolt right on to a 350. Water pump, fuel pump, distributor, alternator and A/C brackets should be a direct interchange.

Originally Posted by J. Robinson

Good advice from Roger. A basic crate engine can often be more cost effective than trying to build or rebuild the engine yourself. Check prices both ways. However, if you've never been into building engines, there is a lot to learn; it may be wise for you to find a friend or family member who has done it before and is willing to "walk you through it" the first time.

One thing that is helpful - small-block Chevy engines are all dimensionally the same on the outside. All the pulleys, brackets, and accessories from your 305 should bolt right on to a 350. Water pump, fuel pump, distributor, alternator and A/C brackets should be a direct interchange.

all of this is appreciated. my friend looked at an ~85 *edit: it's an 87* 350 and a 70s 350 and said it looked like the newer water pump wouldn't fit on the older 350. this led me to believe nothing would be able to transfer over. isn't the 350's alternator usually on the passenger side? my 305's is on the driver's side. *edit, the crate motor would be the proper year for all of my accessories, but if i go with an older motor, i'd still be interested in knowing.

Originally Posted by glennsexton

Welcome to CHR!

All of the accessories will bolt up from the 305 to the 350, AC, alternator, power steering pump, water pump, pulleys, etc. I'd invest in a new water pump simply because the one on the 305 is 31 years old. The alternator may be a good one to swap out as well as new belts and hoses.

Carefully clean and label everything as you disassemble - take lots of pictures and write everything down. Make sure you disconnect the battery and remove it before you begin removing the accessories as a quick short to ground can make a real mess of wiring that's a pain to replace.

You'll need a different manifold for the 350 - not due to size - but to go back to a carburetor. I'd recommend a Weiand spreadbore manifold and a fairly stock 750 Quadrajet (Summit Racing is a good source).

I'm assuming you have access to a garage, an engine hoist (you can rent one as well) and a good engine stand.

Assemble all your parts, ask us lots of questions and you'll be just fine.

Let us know how you decide,
Glenn

thank you. i mostly need help assembling my parts and thinking the build over. the efi 305 to any carb 350 is a drag and drop, right? i won't have to modify any wiring harnesses? i have someone with experience pulling and dropping sbc's, but isn't updated on new tech.

https://www.summitracing.com/parts/vre-350g8795

is this a good option? it's on the cheap side of crate engines, but 350 mystery facebook motors are cheap as dirt in comparison. my friend picked a 350 up for something like $200 after seeing it run. i guess i'll see for myself if he got lucky or screwed when he gets it in.

new water pump, new belts and hoses, intake, carb..

do you guys prefer a 700r4 or 350 trans?

I personally would not use this crate engine as it is a flat tappet cam. I recommend roller cams for almost all applications as the break in for flat tappet is critical and if not done correctly, the cam can be compromised in the first few minutes of operation.

A good roller cam long block will be in the neighborhood of $2,500-3,000. Add in a new water pump, intake and carburetor, belts, hoses, fluids, etc.., and you break the low $3,000 mark real easily.

There is another option – if you have a u-pull-it wreaking yard you could get a 350 from a 90’s Chevy or GMC pickup. These are roller 350 engines and tough as nails. Most yards will guarantee a running engine that doesn’t smoke and this would be a true drop-in replacement for your tired 305. If you can get an engine/transmission combo - all the better. This could be a solution for under $1,000.

Whatever you decide, your sweat equity will be required. It sounds like you’ll also need to solicit some help (if nothing else to assist in removing the hood from the beast and pulling the engine).

Lots of opportunity to learn here – keep us posted.

X2 for what Glensexston said. If you're just looking to upgrade to a 350, a boneyard 350 out of a Chevy pickup would be an easy drop in. I am not even sure if you would have to switch the computer or not. 500 bucks would go a long ways to being done going that route.

this thread might be here and there for now, but does anyone have info on an efi 305 swap to an lt1? probably out of an impala SS. whether it's another thread or just posted here. if i got a complete lt1, dropped it in place of my 305, would i need a new wiring harness, or could i use what i have between the two engines? i found a video of someone with the swap but can't find much info for my application. i'm just wondering which swap i should put effort toward researching, since the regular 350 will probably cost more brand new than a good used SS LT1.