Original TBI 350 needs to be rebuilt and I am thinking this may be a time to upgrade.

Looking for recommendations since I know there are a few on here that have done something like this more than once.

It is a 1989 V1500 Suburban.

I'm thinking of swapping for a LM7 and while I'm at it replacing the 700R4 with a 4L60E. I wouldn't mind having a little more than stock HP but realize that its probably not needed as I will already be getting more than this thing rolled off the line with.

Its not going to be a race truck or a rock crawler. I'll probably drive it around town quite a bit when I am taking all 3 kids somewhere and it will take the occasional road trip, camping etc.

Thanks in advance.

I have nothing to add on the engine situation, but post some pics. Those old suburbans were the best.

5.3/60e is certainly a great setup for what you're after. I don't recall how compatible the 700r4 is with LS 60e in regards to transfer case.

Alternatively, for a more straightforward swap, you could drop in a vortec 350 (L31) with a carb intake & Holley Sniper EFI. L31 is a hydraulic roller engine, so it'd be fairly easy to toss a mild cam in. If you still want a 60e over 700r4 with L31, you can just buy a standalone controller for the trans.

I'm looking at getting a crate engine. On Jeggs there is a pretty big price difference for what looks to be the same engine made by ATK and one made by GM (both remanufactured)

https://www.jegs.com/i/ATK-Engines/059/VCT84WD/10002/-1

https://www.jegs.com/p/Chevrolet-Performance/GM-Goodwrench-Truck-53L-LM7-L59-285HP-Crate-Engine/1696860/10002/-1

I think they both come with 3 year warranties. Any reason to be suspect of the ATK?

If you're looking to go crate, I'd probably go with the below. Any time I had an issue with part ordered from Summit, they did a great job of taking care of me. I'm sure that they would provide best support if you have any issues with engine itself.
https://www.summitracing.com/parts/sum-150153

You're going to spend a ton more money going crate rather pullout. You'll still need to source accessories, brackets, intake, TB, covers, etc.

I've ran 3 junkyard pullouts and haven't had issues with any. The first of those engines was ran in two separate trucks of mine lol

Jasper engines have great warranties.

will.mcg said:

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Jasper engines have great warranties.

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Never had first hand experience with Jasper, but I have heard a lot of complaints about their quality

silverado_lover said:

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5.3/60e is certainly a great setup for what you're after. I don't recall how compatible the 700r4 is with LS 60e in regards to transfer case.

Alternatively, for a more straightforward swap, you could drop in a vortec 350 (L31) with a carb intake & Holley Sniper EFI. L31 is a hydraulic roller engine, so it'd be fairly easy to toss a mild cam in. If you still want a 60e over 700r4 with L31, you can just buy a standalone controller for the trans.

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The output shafts are the same 27 spline design between the 700r4 and 4l60 (LS and LT). Big difference between them in input shaft and converter size. An LT4l60/700r4 converter won't work on an LS 4l60.

I knew outputs were same, but I'm not so sure about the bolt pattern for mating transfer case to 60e. When I was looking at mating NP203 to LS 60e, I seem to recall there was adapting required.

I don't want to **** with it so I'm just going to stay Gen I for that build lol

Wouldn't this beg for LQ9 out of a van or 2500 with no active fuel management.

LQ4 out of van/2500/Denali
LQ9 out of Escalade/SS/Vortec Max

None of the above or an LM7 have AFM.

LM7 with headers and tune will feel like a rocketship coming from a 350 TBI. Speaking from experience

silverado_lover said:

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I knew outputs were same, but I'm not so sure about the bolt pattern for mating transfer case to 60e. When I was looking at mating NP203 to LS 60e, I seem to recall there was adapting required.

I don't want to **** with it so I'm just going to stay Gen I for that build lol

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Ha! Yeah the 700r4 has the 4 bolt transfer case adapter. 60e is 6 bolt.

Is LT 60e 4 bolt or is it 6 bolt as well?

Pics!

I guess I need to be getting more pics of the truck. I'll add more later. Here she is the day I picked her up in Midland a few years ago.

https://photos.app.goo.gl/Wr5qbmmF1BpY4Rqm6

ozzy said:

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I guess I need to be getting more pics of the truck. I'll add more later. Here she is the day I picked her up in Midland a few years ago.

https://photos.app.goo.gl/Wr5qbmmF1BpY4Rqm6

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One of my favorite Chevy paint combos.

That thing is awesome. I honestly think it'd be cooler/more unique to keep it gen I.

This is awesome. I want to do something similar but I keep getting hung up on the interior. It seems like you can upside down quickly trying to keep up with broken AC, power locks, power windows, gauges, etc.

I lucked out in that this one was in pretty good shape on the interior. Everything works. It got a new headliner and I cleaned the crap (figuratively) out of it. Was missing the 3rd row seat but I was able to get one shipped from a junk yard. Didn't get rid of the west Texas dust smell till I took apart the AC ducts and cleaned them.

It's fun to drive. Accelerates like a golf cart, corners like a boat.

Decisions. I like that its all original now.

Now you've got me wondering if I should go with something like this to get a little more power.

https://www.summitracing.com/parts/mll-bp350tbict

or a 383 Stroker

Any reason you couldn't put a big block in there? Gas mileage would suck but power would significantly increase.

That was our deer lease vehicle.

I was driving across a pasture and sent one airborne on accident. Incredibly reliable and could hold up to the abuse.

I'd do the LS 6.0 swap. It's just better all around than the 350.

If you were to stay with SBC, how does the original TBI compare to a Holley Sniper?

https://www.phoenixengine.com/Chevy-16.html

you could run a sniper set up on that motor and make up to 375 hp.

The main difference is tunability. OBDI is very outdated and hard to find someone to tune it. If you manage to find someone that can do it, it'll be a painstakingly long process.

Holley Sniper can self learn and will be drivable very quickly. If you're not stoked with how it's driving, it'd be easy to find someone to tune it or possibly learn yourself.

Finally got around to doing this last fall. I went with what was described as the drop in 350 TBI replacement from Blueprint Engines.

Things are mostly going great but I am getting an intermittent Code 43 (ESC/Knock Sensor). I've been chasing it around for a while now. It started as something that would trip any time I accelerated hard. Replacing the MAP sensor and TPS fixed that and made it more intermittent.

I continued troubleshooting using the manual and one of the bullets says to ensure that the wire from CKT 453 to the distributor should have a good contact to ground.

Here I could use some help interpreting the results I am getting or comparing to known good part if anyone has one.

CKT 453 is one of the wires plugging in to the ICM on the distributor. For my truck it shows up as EST REF LOW but in newer manuals the same CKT I think is call IC REF LOW.

When I disconnected the plug from the distributor and check continuity between the the pin in the plug and the end of the negative battery cable I get 50K Ohms (K is not a typo).

I hooked everything back up so I could get it out of the driveway.

The next day validated that the ECM had a good ground by checking A12 in the ECM harness to the end of the negative battery cable. I get <1 Ohm. ECM ground appears to be good.

I check the other half of the circuit and notice that when I move the lead for the multimeter from A12 to B3 (other end CKT 453) I also get <1 Ohm. This seemed odd but when I check schematics the ICM is tied to ground through one of the screws that installs it to the distributor and the distributor to the engine block.

I then checked between the B3 and A12 pins on the ECM itself and found my 50K Ohm reading.

Question for the board is if the 50K Ohm through the ECM is right or not. I've found one thread on the interwebs that describes this check as being done through the ECM but they way the manual reads it isn't clear how that should be checked.

For what its worth the manuals for newer vehicles read the same way in regards to CKT 453 even if the vehicle uses a different ECM

ozzy said:

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I went with what was described as the drop in 350 TBI replacement from Blueprint Engines.

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Godspeed, carb or Holley Sniper swap if you can't figure it out.

Quote:

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Godspeed, carb or Holley Sniper swap if you can't figure it out.

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Aggh

ozzy said:

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Quote:

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Godspeed, carb or Holley Sniper swap if you can't figure it out.

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Aggh

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To be fair, you did exactly what the board recommended against doing.