Okay I have been struggling for a while now finding a compatible engine. I was told by some people truck/suv 350's work. They do not. They are flat tappet not roller like the Camaro and some other differences. I have looked and looked with no luck, I am trying to find a 350 TBI that works directly in a 92 Camaro. One that is compatible with stock setup like the 61lb fuel injectors, LxE6 ESC, the 305 ECM (should work in both if the proper stock engine), and has the same wiring harness. I've asked around a TON and people keep saying, yeah it's all cross compatible yeah it all uses the same but I am finding it does not. I am just really struggling finding the Engine I need. Should I just buy a 91-92 Caprice 350 Engine? I was told those are directly compatible, it's just been extremely hard to find one. I would love you forever and appreciate you more than anything in this world if I could get some direct links, if you've done the swap direct me to what you used that worked! I wanted to just pay someone to find the components and do the swap but everyone in my area hates doing engine work anymore so they no longer do swaps unless you provide the setup (I don't have a lift or any tools at home to do it myself).

 

So you have a 305 and are wanting to do a 350 swap, yes?

There are some parts that can be reused, and several that cannot. It's not as simple as just pulling the engine, dropping the 350 in, and hooking up all the 305 electronics. This thread outlines everything you need:

https://www.thirdgen.org/forums/tbi/...-350-swap.html

 

Later flat tappet blocks can be converted to roller, but flat tappet cams also open and close valves so if you're going for a budget deal, just leave it in there. One thing I would not do, is replace a working flat tappet cam with another flat tappet cam. It's still going to make more power than a 305. You should be able to reuse your existing harness, etc, so what are these incompatible differences?

 

L05 350 pretty much direct replascement and will run decent on the stock 305 tune because they are both so mild. Put a lil more spring pressure to your TBI ( like say 14lb spring )and you should be good to go with much more torque than the old L03

 

A TBI LO5 350 for an 88-94' full size pickup truck would be the most direct replacement. Everything should bolt up to it. You would need a knock sensor for the 350 (look one up for the truck). The Lo5 would run OK on the 305 injectors with a bump in fuel pressure, but 350 injectors and a PROM chip change would make it run better. This is the most straighforward swap.
ALL NEW ! GM 5.7L 350 L05 Gen 1 87-95 Truck Crate Engine 210HP - ETA LATE JANUARY: GM Performance Motor

You could also go with a Vortec L31 350 from a 96'-00' pickup truck, but there are more differences that you would need to work around. You would still need to 350 knock sensor and would also need a Vortec TBI intake manifold since the stock TBI intake will not bolt up to the Vortec cylinder heads. The TBI EGR system doesn't work with the Vortec heads, so you would need an external EGR kit or eliminate the EGR altogether. 350 injectors and a reprogrammed PROM chip and also headers because the rearmost bolt on the passenger side exhaust manifold will not work on the Vortec heads. Some people leave that last bolt out and have no issues, but it could result in an exhaust leak. Headers will bolt up.
ALL NEW ! Vortec 96-02 350 L31 Crate Engine - ETA Late January: GM Performance Motor

The L31 will give you 30-40 horsepower more than the LO5, however there is more to work around to get it to work.

There are other options for 350's out there, but these are the most direct bolt in replacements to what you have and are 100% brand new GM engines.

 

The Best Chevrolet Small Block 350 that GM produced...
ONLY came in Trucks/ SUVs.

It absolutely has Roller Lifters/ Camshaft.

...The ORIGINAL Vortec Engine (NOT the Gen-III/ IV SBC Vortec Engines) 5700!

As already Posted, 1996 and Up 350s are what you want!


Putting Truck Engines into Cars back in the Early 1960s is what GM did to start the Muscle Car Era!

 

Vorteciroc, (PM sent) are you stating OP should go with the GM engine, "TransamGTA350" posted the link to?


https://www.gmperformancemotor.com/parts/19432780.html

 

Not if the Original Fuel Injection needs to be reused... the Intake Manifold will not fit those Cylinder-Heads.

Otherwise... Yes.

 

Scoggin Dickey lower intake manifold to solve the problem?

Confirming the engine in the GM Parts link, is the one you were speaking highly of? Thank you.

 

This is the Vortec TBI intake. It's a little pricey though.

TBI Intake for Vortec Heads Chevrolet Performance Parts (paceperformance.com)

 

Yes and Yes.

Spend the extra $ for an Aftermarket Camshaft and Valve-Springs...
The Vortec TPI set up can do 375 HP and 475 Ft/Lbs.

Swap to a Vortec Performer RPM Air-gap (and an appropriate Camshaft/ Springs) with a 4BBL Throttle-Body (or Carburetor) and...
Make a good 450 HP and 400 Ft/Lbs.

 

Back in the day...
I used to build and sell a TON of 383s with Vortec Heads, Performer RPM Air-Gap, Cam, Etc...
Easy 500+ HP and 450+ Ft/Lbs.

Toss on (back then very popular) 1 or 2 Stages of Nitrous-Oxide...
700 - 750 HP!


Those were the easy days!
Now everyone wants a 1,000+ HP turbocharged Gen-III/ IV SBC!

 

Do you know if Performer RPM Air Gap, quadrajet and stock air cleaner will fit under stock hood?

 

It absolutely will not.

 

Just curious on your thoughts about starting with a 1985 LG4 and
then making those mods to it ???

 

Sadly I do not recommend that course of action...
Most modern Gen-I SBC Cylinder-Heads are restricted (Valves can NOT UnShroud adequately) on Bores smaller than 4.00"

 

The things I listed like the 61lb fuel injectors, knock sensor etc would be upgrades. I currently have the 305 and its smaller injectors etc. The parts I listed are what I was told I needed but I wasn't given the specific engine those upgrades would work on, like I assume depending on the 350 it requires different components. I just wanted the 350 TBI not TPI so I assumed it was the caprice engine people were mentioning with those upgrades since it seems like the lxe6 and 61 injectors were for those. I already have an aftermarket ecm that is compatible with both engines I double checked on that.


I should mention too, I spoke with Jegs and when I asked them about it they said the truck ones wouldn't work due to the tappets and oil pan being a different size. So idk... But yeah, I basically just want a 2 bolt that besides some of the smaller components like injectors etc can essentially plug and play. I was told the 350 tbis use the same pully system, alternator, and water pump as the 305?

 

I'm not sure what you mean by tappets? Do you mean flat tappet hydraulic lifters vs. roller hydraulic lifters? If that's what you're referring to, it's not an issue. The L05 truck engine did have flat tappet hydraulic lifters, but it's internal to the motor and it works fine. Roller lifters are better, but it's not a dealbreaker it wouldn't stop me from buying a new long block. The L05 Caprice engine did have roller lifters, but I don't know if you can get one of those new. I've only seen the truck L05 long block available. The 305 L03's were the same deal. The car versions had roller lifters and the truck versions were flat tappet.

All of the exterior accessories, water pump, oil pan, valve covers, intake, etc. will transfer from the L03 to the L05. Externally, the long blocks are identical.

 

​​You guys are awesome! Yeah, that was exactly what I meant. I was hoping for the rollers, will the oil pan fit okay? L05. I am so new to this so I apologize.

I do see one issue with the ones you linked. Mine is a 2 bolt and that's a 4. Is there a 2 bolt that will plug and play that you like so I don't have to alter mounts?

https://www.jegs.com/i/JEGS/059/8758/10002/-1
this is the one I am looking at.

Edit: I found from Jegs this one should plug and play with my car minus the basic components that need to be replaced, my question is, does this one take 61lb injectors? Does it have an esc module? If so which one and which rod knock sensor? Jegs didn't have that info and I am not sure how to find it. I don't even see an actual model # to look up matching parts.

Also, Summit's version of this engine says it has the mechanical fuel pump boss cast into the block but it has not been drilled or machined out. I assume it works with my federal mogul electric fuel pump but has that so you can do the carb/mechanical conversion?

​

 

2-bolt vs. 4-bolt refers to the main bearing caps that hold the crankshaft in the block. It's internal and has nothing to do with the external motor mounts. Either will work for you. 4-bolt mains are stronger, but for the power level you are looking at, it won't matter.

That Jegs motor will work, but it's a remanufactured, not new. No idea on the quality of the rebuild. Jegs doesn't do it themselves, it's done by a vendor and they put their name on it. I don't know who they use, so can't say if they are reputable or not. That motor is $2K, but also has a $500 core charge. So, since you don't have a rebuildable L05 350 to send back to them, you need to include the core charge in the total cost of the motor, so $2,500. A new GM L05 350 is $4K for comparison.

I don't know the specific flow rates of the injectors. I would use injectors from the truck L05 (88-94 pickup) and have a PROM chip burned for the new injectors. But, before I did that, I would fire it up on the L03 injectors to make sure everything is working OK. You could also use the L03 injectors with an adjustable fuel pressure regulator and turn the fuel pressure up a little bit. It should run pretty good that way and you can always do the new injectors and PROM chip later.

Use a knock sensor from a 92 Z28 with a 350 TPI. It's not there to detect rod knock. It's there to detect the pistons rocking in the bore due to detonation (pre-ignition). The knock sensor is tuned to the natural frequency of the cylinder walls "ringing" when the piston hits the cylinder wall. A 305 and 350 have different cylinder bore diameters, therefore different natural frequencies.

Don't worry about the fuel pump. The mechanical fuel pump is for a carburator. All small block chevy bare blocks have the fuel pump mounting boss cast into them. The L05 is fuel injected and doesn't need the mechanical fuel pump, so GM didn't machine the fuel pump mounting surface and didn't drill the hole in the block for the fuel pump pushrod because there was no need. Some blocks are machined and have the hole, so in that case you would just use a blockoff plate.

 

Quick question...the Brand New, GM LO5 350 linked above, is that an L98 ? Am I seeing EGR supply port, with a drilled/tapped hole above said EGR port?

 

No, L05 is not L98.

The heads, intake, camshaft, and exhaust are different. There are also smaller differences in the short-block, but those don't really impact power production.

That said, an L98 is significantly less powerful than modern versions of the SBC like the Vortec based engines from the late 90's. Head flow, and intake design means they make much more power with similar torque output.

 

You would expect the Vortec based 350 to make more HP and torque, yet when I look up the rated power, I am not seeing much diferance. (I'm considering a L98 or L31 to replace the OE LB9 305 TPI in my '89 IROC Z Vert).

 

A stock L98 and stock L31 are going to produce about the same power (250hp give or take). The L98 has a more aggressive cam, but poorer flowing heads. The L31 has a smaller cam and better flowing heads. They tend to net out pretty close. An L31 is a reasonable stock replacement for an L98, except that you need a specific intake manifold for Vortec heads.

Yes, an L31 has more potential with a cam swap, but stock for stock, they are going to perform about the same.

 

THANK YOU.

 

Plus if you would like to make more power later, you have an easy avenue to do so with Vortec Heads.

Maybe a little Turbo!