Chevy 350 Swap Reliability?? (1 Viewer)

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LucyProject

FJ Adventures
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Feb 10, 2019
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Centralia, WA
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For those of you that have installed a gen 1 350 crate motor, how has the reliability been? I bought a FJ40 with a seized 350, and was going to drop in a new crate 350 with EFI from Summit or JEGS into her - for ease of application, and cost. But, I want longevity more than horsepower. Thanks in advance for sharing.

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I would expect you to see 150k or more. A moderate engine like you are thinking about would be a good choice in my not so humble opinion.

Larry in El Paso
 
How much are you looking to spend on that motor? Have you considered jumping to a 5.3? I'm not expert, but I think it would drop in similarly to the 350, except for the computer - but the new 350 you are talking about would have a computer too.
 
Longevity is determined, in part, by maintenance, environment and driving style. Moderate use of the skinny pedal and regular service should get you to 150k.
I agree that a 5.3 LS series engine is a MUCH better choice. It's a modern platform, plenty of parts and support, better fuel economy and fits in the same space. Absolutely worth the extra effort. Adapters allow use of your SBC mounts. Much smoother throttle response, plenty of torque.
 
Longevity is determined, in part, by maintenance, environment and driving style. Moderate use of the skinny pedal and regular service should get you to 150k.
I agree that a 5.3 LS series engine is a MUCH better choice. It's a modern platform, plenty of parts and support, better fuel economy and fits in the same space. Absolutely worth the extra effort. Adapters allow use of your SBC mounts. Much smoother throttle response, plenty of torque.
Only downside is they are often 2-3 times the price for a used engine. I can find running 350's and other SBC's for $200-500 while most yards want $1000+ for a well used LS series engine, might be different in other areas though. I thought about finding a 4.8 for my swap but I keep comeing back to the old SBC and varients based on price.
 
I've run Chev engines in my 40 since about 1985. The 1st motors I used a were good used engines. Hot SBC's and a BBC, then I purchase a new GM crate engine about 15yrs ago, and have had no problems with it. It's been raced and wheeled hard. I believe GM warranties a new GM crate engine for 2yr/50k miles. I would think, reliability issues would probably be more related to the quality to the installation than the engine itself.
 
Our ramjet has about 15k on it. Initial problems with idle took some time to sort out. So far, only the water pump has needed to be replaced (apparently, GM included a reman from Mexico in the accessories package) This is the third GM V-8 in the vehicle since 1979.

Other 1975 FJ40 has a used 350 from a '98 or so Suburban. Unknown miles, but about 20K by me since purchase. Very reliable so far. Impressive acceleration and 15mpg or so.

I would do a first gen V8 or vortec again in a heartbeat.
 
Only downside is they are often 2-3 times the price for a used engine. I can find running 350's and other SBC's for $200-500 while most yards want $1000+ for a well used LS series engine, might be different in other areas though. I thought about finding a 4.8 for my swap but I keep comeing back to the old SBC and varients based on price.

Just my opinion. It makes no difference to me either way. I've literally been through every stage of the Chevy engine evolution on the old Gen I platform (I'm an old fart), beginning with the original 265 V-8 in my first car, a '55 Chevy 2-door hardtop. I've been through carbs to multiple carbs to propane to throttle bodies and TPI, and I resisted going to the LS-series engines for a LONG, long time. I wouldn't switch back now even if you gave me a brand new SBC crate motor for free.

On a side note, I know some folks have heartburn over computers (ECU, PCM, ECM, ECU, whatever). I say 'get over it'. Literally MILLIONS of cars and trucks, including all modern four wheel drive vehicles, have them and they work flawlessly every day. The one thing my Gen I SBC could NEVER do is tell me why it decided to wake up one morning and run crappy for no apparent reason. My LM7 can tell me why, and everything else that's going on right now when I plug in a scan tool.

FWIW, my son just picked up a complete LM7, w/PCM for $700.

Like I said, it's just my 2 cents worth. Ultimately, everyone needs to be content with their decisions. After all, this is supposed to be fun ;) .
 
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Just my opinion. It makes no difference to me either way. I've literally been through every stage of the Chevy engine evolution on the old Gen I platform (I'm an old fart), beginning with the original 265 V-8 in my first car, a '55 Chevy 2-door hardtop. I've been through carbs to multiple carbs to propane to throttle bodies and TPI, and I resisted going to the LS-series engines for a LONG, long time. I wouldn't switch back now even if you gave me a brand new SBC crate motor for free.

On a side note, I know some folks have heartburn over computers (ECU, PCM, ECM, ECU, whatever). I say 'get over it'. Literally MILLIONS of cars and trucks, including all modern four wheel drive vehicles, have them and they work flawlessly every day. The one thing my Gen I SBC could NEVER do is tell me why it decided to wake up one morning and run crappy for no apparent reason. My LM7 can tell me why, and everything else that's going on right now when I plug in a scan tool.

FWIW, my son just picked up a complete LM7, w/PCM for $700.

Like I said, it's just my 2 cents worth. Ultimately, everyone needs to be content with their decisions. After all, this is supposed to be fun ;) .

You are correct, but I have a $20. vac gauge that does the same thing all the time for a lot less money. :)
 
Really hated to give up the six and go with a 350 back in 1985 but time and money was an issue.
I had been taking long highway drives about that time so the V8 handled that type of driving better.
The first 350 was a used one out of 75 Belair. Can't remember how many miles it had on it when I got it but put a good 100K on it the first ten years of driving.
The engine is as basic as one can get and when I finally decided to rebuild it kept it that way except for an HEI up grade.
Have about 75,000 on the rebuild and it is going strong.
In all the years the chevy engine hasn't missed a beat.
Pulled the oil pan a couple thousand miles ago to have a look and the pan was as clean as the day I rebuilt it.
As much as I liked the six it would take a lot for me to go back now.
 
Like others have said the SBC is a good engine. Mine will hum down the road and idle up the rocks, then hum back down the highway. Exactly what I built it for. If I were to do again, I’d wait for an ls in my price range. I may have drank the cool aid, but they’re just smoother. Of course I’d update the trann(nv4500) and transfer(split?) if budget allowed.
 
Really hated to give up the six and go with a 350 back in 1985 but time and money was an issue.
I had been taking long highway drives about that time so the V8 handled that type of driving better.
The first 350 was a used one out of 75 Belair. Can't remember how many miles it had on it when I got it but put a good 100K on it the first ten years of driving.
The engine is as basic as one can get and when I finally decided to rebuild it kept it that way except for an HEI up grade.
Have about 75,000 on the rebuild and it is going strong.
In all the years the chevy engine hasn't missed a beat.
Pulled the oil pan a couple thousand miles ago to have a look and the pan was as clean as the day I rebuilt it.
As much as I liked the six it would take a lot for me to go back now.
Coincidentally my first SBC in ‘96 was a Sept ‘69 Belaire 350. It had about 100k miles when I started. After about 20 years the $300 engine spun a bearing. I cracked it open, found flat top pistons, and almost no ridge.
I had decided to rebuild it when I stumbled appon a 70k 350 out of a ‘72 Fleetside for $300 with an unneeded TH350. It was a no-brainer... when I opened it up to replace all the gaskets I found it to be an extremely clean 4 bolt main (inside)... so I thanked my lucky horseshoe and bolted it back up with a new True double roller timing chain, an RV cam, and an SP - 2P Edelbrock intake, and a 1406 Edelbrock carb. It’s incredibly smooth running and continues to pull well below idle (<500 rpm).
Like others have said the SBC is a good engine. Mine will hum down the road and idle up the rocks, then hum back down the highway. Exactly what I built it for. If I were to do again, I’d wait for an ls in my price range. I may have drank the cool aid, but they’re just smoother. Of course I’d update the trann(nv4500) and transfer(split?) if budget allowed.
I had a balanced l6 that was silky smooth... but I agree the V8 is smoother and happier at higher RPMs than a stock l6.

OP, 350/SBC are extremely reliable in Cruisers. They can potentially overheat if cooling isn’t taken into consideration.
 
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Coincidentally my first SBC in ‘96 was a Sept ‘69 Belaire 350. It had about 100k miles when I started. After about 20 years the $300 engine spun a bearing. I cracked it open, found flat top pistons, and almost no ridge.
I had decided to rebuild it when I stumbled appon a 70k 350 out of a ‘72 Fleetside for $300 with an unneeded TH350. It was a no-brainer... when I opened it up to replace all the gaskets I found it to be an extremely clean 4 bolt main (inside)... so I thanked my lucky horseshoe and bolted it back up with a new True double roller timing chain, an RV cam, and an SP - 2P Edelbrock intake, and a 1406 Edelbrock carb. It’s incredibly smooth running and continues to pull well below idle (<500 rpm).

I had a blast at alanced l6 that was silky smooth... but I agree the V8 is smoother and happier at higher RPMs than a stock l6.

OP, 350/SBC are extremely reliable in Cruisers. They can potentially overheat if cooling isn’t taken into consideration.

The radiator in my FJ40 was a four row so with a shroud and a stainless flex fan the 350 ran cool even pulling a trailer in summer.
In mid 90's after the rebuild the stock radiator got to the point it could not be reliably rebuilt I search around and wound up putting in a new three row and with the same shroud and fan had heating problems on hot days even while not pulling a trailer.
Struggled with that setup for a few years until they invented the computer and I found an aluminum 4 row on E-bay.
Now with the 4 row and an electric fan with shroud it is back to happy engine temps again.
I debated between a aluminum or a brass radiator and decided on the aluminum but that is another whole debate.
 
I've got a brand new, base, 195HP carbureted 350 in my 40. It replaced a rebuilt 283 with unknown mileage. I only have about 1000mi on it so far but all in all I am happy with the performance. I can't speak to reliability yet...

I will say that cooling is the big issue. We had several hot (90+) days this summer. I have a 4-row, OEM-style (made by CSF) radiator with a shroud and 17 inch mechanical (no clutch, no flex) fan. Sitting in traffic (poor air flow) temperatures would creep up to around 215 degrees when it was hot. In Winter, it has been running closer to about 175-180 degrees at idle. So I'm sort of stock between under-cooling in summer, and overcooling in winter. My understanding, however, is that a SBC is "happy" as long as temperatures stay under about 230 degrees and you don't boil the coolant. Let me tell you though, a SBC at 215 degrees jammed up against the firewall with exhaust under your feet makes for a HOT ride in the summer.

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Had a 350 with an RV cam in a 67 FJ40. It was rebuilt with about 5k on it when I got it. It got very little use so I pulled the engine and resealed it. It had a Quadrajet that was bad. Instead of rebuilding, I opted to go junkyard TBI. I pulled the computer/TBI harness, intake from a police cruiser. Got a pump from the parts store along with an O2 sensor and opened up the wiring schematics.

It really wasn't that hard all. The only issues I had was that I had to switch back to a manual fan as the electrical Taurus fans caused some issues with the computer and it would act all sorts of weird when they kicked on. The manual actually cooled better.
The other had to do with the Vehicle Speed sensor which I was too cheap to spend $200ish on at the time. Only issue with that was sometimes the engine would lope weird at idle, but that was it.

All in all, the TBI turned that 350 into a MUCH more enjoyable starting/driving rig. Those 350s with good maintenance will last 150K plus pretty easily. Worst case a rebuild or buying a rebuilt engine is pretty dang cheap.

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I've got a brand new, base, 195HP carbureted 350 in my 40. It replaced a rebuilt 283 with unknown mileage. I only have about 1000mi on it so far but all in all I am happy with the performance. I can't speak to reliability yet...

I will say that cooling is the big issue. We had several hot (90+) days this summer. I have a 4-row, OEM-style (made by CSF) radiator with a shroud and 17 inch mechanical (no clutch, no flex) fan. Sitting in traffic (poor air flow) temperatures would creep up to around 215 degrees when it was hot. In Winter, it has been running closer to about 175-180 degrees at idle. So I'm sort of stock between under-cooling in summer, and overcooling in winter. My understanding, however, is that a SBC is "happy" as long as temperatures stay under about 230 degrees and you don't boil the coolant. Let me tell you though, a SBC at 215 degrees jammed up against the firewall with exhaust under your feet makes for a HOT ride in the summer.

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In the past my 350 has gotten up over 220 and closer to 230 with no adverse effect but I rest easiest with the needle at the prescribed 190.
I ran street huggers when I first installed the V8 then when I rebuilt it I put on a set off ram horns. They hold the heat and the engine ran a bit hotter plus it also seemed to make the cab warmer in summer.
I went back to the headers and the gauge says the engine is cooler but can't say for sure how much cooler the cab is as it still can get stuffy in the summer.
Best cure for a hot cab is pop the top, on the cruiser that is, wait till you get home before you pop that other top.
 
I see you're in Washington, so I don't know what your local prices are like, but I see complete LS engines every day on Craigslist for less than $1000 here in Nebraska. I paid $300 for my L33 5.3LS complete with ECM. I had to pull it, and that saved me $200. I'll end up paying more for the Advanced Adapter to mate the auto to my split case than I have into the whole rest of the drivetrain.

That being said, I had a 400 SBC in my 40 before I started the LS swap. Other that running a little hotter than a similar 350 because of the Siamese ports, I never had any trouble with it. Started out with a Q-Jet, then swapped a 600cfm Edelbrock carb.

I haven't gotten any miles on the LS swap yet, its my winter project. But I haven't heard of anyone regretting doing the LS swap.
 
350 conversions got a bad rap starting about 20 years ago as many were just cobbled together with fly by night conversion kits and companies. In the last 10 years or so, there have been a few reputable conversion vendors which have these swaps very reliable

My sell on the 350 is the gen I or II: That's because it is one of the most common engines in the world. Try getting a water pump or a belt for a inline 6 Toyota engine in nowhere USA. I was stuck in the San Luis Valley with a broken belt on my 350. There was NOTHING in the area. A farmer pulls up and says a NAPA store is about 3 miles away, would I like a ride? (This NAPA was in the middle of a row of silos, NO other stores) in about 20-30 miles.

They are easy to work on, parts are cheap and available everywhere
 

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