So I found out that my little 3.4l v6 has lifters that are going bad. Most likely assumed from the car going from sitting for a year or so to a daily driver. Now the lifters are pretty cheap, easy enough of a fix if I really wanted to, but I wanted to start a new. Only to find out the 3.4l are discontinued engines and any place that does still make them wants $2600. I can buy an RB25 turbo engine, 5 speed tranny, ecu, etc out of a skyline for $2000 if I wanted to.

So that leads me to look for a V8 that is mass produced. Now I initially wanted the V6 to calm the weight in the front end, but the LS1 being aluminum for the most part seemed to even out the weight even being a bigger motor, unlike the LT1 which was still cast and much heavier. Only one problem. Im looking at an easy $6000 for one of those engines used, and finding a parts car is near impossible where I live.

I searched around and came across the LM7 engine out of Chevy and GMC trucks and see nothing but great things about this engine. Both vin code T and Z. Between 2000-2003, these engines were made to be basically bulletproof and still have the same upgrade responses as the LS1. Its also set up with an aluminum block like the LS1.

Now I have a 1994 3.4l V6 with an automatic tranny. Now Im sure Ii will need some modification as far as braces and mounts go, maybe a custom driveshaft depending on where it mounts up at, and possibly a different hood depending on the height of the engine.
My question is, will this engine bolt right up to my transmission or will I need a whole new tranny as well to put this engine in?
Also, which ecu should I use? The LS1, the LM7, the 207? Im kind of mix and matching here so Im not sure.

Those are my only concerns are the ecu and mounting up to the tranny. Other than that, braces and mounts, driveshafts, etc, aren't much of a concern. I can grab one of these engines with low miles easily for $600 all day long around here. And since its only lifters in my engine that are going bad, I have a while to gather everything together.

 

Why not rebuild the 3.4? Or just replace the lifters? Also, from my knowledge, the LM7 (vin T) is a cast iron block and aluminum heads, just like the LT1. Vin code Z is a L59 which is the flex fuel version. Vin P and B are a LM4 and L33, respectively, which have the aluminum block and heads.

You will need a new trans for sure. A new k-member as well. Might as well put a one piece driveshaft in while you're at it. You'd have to switch the intakes for hood clearance as well. Exhaust may need to be modified. I'm sure I'm forgetting some things, but it would take a lot work and a few weeks down time for it to happen.

 

fix the 3.4

 

If you had a way to get, I have a low miles rebuilt 3.4 laying around

 

Slick, how much would you be asking for it? I could probably get down there depending on how much you wanted for it.

MK, it is a simple fix and cheap, but I wouldnt doubt something else to fail shortly after. This is normally a very reliable engine but since it went from sitting, to daily driving, it apparently shook it up a bit.
And youre right, I mixed up the 2 blocks. I forgot Ii decided to go with the LM7 anyhow because it was more durable. The L33 with the aluminum block is what I originally wanted but Ii found out its famous from the cylinder walls cracking. My mistake, I jumbled it all together in my head. haha

As for rebuilding the 3.4, I was thinking about it, but the main reason I wanted another engine all together is because this is my daily driver and I dont have anything else to drive period. So I could work on the new engine out of the car, then take a week to swap in the new engine and parts. But taking this engine out, rebuilding it, then putting it back in, Id be looking at down time substantially longer.

There is one other thing I was wanting to know, Ii have an OBD1 port, but that engine works off an OBD2, so wouldnt I have to switch the whole OBD?

Besides The LS1, LT1, and 3.8, are there any other motors that bolt right up to this tranny that would just need other modifications? I dont mind everything else, I just dont want a new tranny as well right now.

 

Im actually reading more and more on the LT1 engines. Despite me wanting to keep the front end as light as possible, I guess another 100 lbs wont hurt too much. Ii can always compensate by lowering the rear in comparison to the front by an inch.
The LTs are a little harder to get my hands on and find, but I can still find them for around $400-$600 in decent shape. Rebuild they are still $1800.

Just a couple questions. Im looking to get specifically the 1995 LT1 engine.
First off, are these known to last as long as the 3.4s in terms of mileage? Almost every 3.4l see's the day off 220k from what Ive noticed.
Are LT1s just as generous on their lifespan?
Also, if I go to swap that in, Im guessing I will need the ecu with it, new radiator, and new gauge cluster. Already wanted to put in a 1 piece driveshaft regardless as well.
Other than that, will this pretty much be a drop in and bolt up engine, no real modification required?

 

You are going to need a doner car. It is rarely worth the work. Check Socoms V8-V8 unproject. There is a link in the V6-V8 sticky thread that lists all the parts you will need from the doner car. The closer to your year the less parts you need.

 

Couple things I noticed here that I want to clear up for you...

True, but just replacing the lifters and intake gaskets/bolts reduces down time to about a weekend.

It's cool. Engine designations get mixed up all the time. Just wanted to make sure we were on the same page so we could give you the best info possible.

Yours is '94 right? 94 was still OBD1. 95 was the OBD1 computer with OBD2 connector.

Those three are about as close to being drop ins as possible...but your current trans will not bolt up to any of them. So you'd have to find a new trans as well.

I know where there are two LT1 blocks for sale, $175 for the pair that are closer to you than they are to me. I was looking at them, but I'm still tossing it in the air because it's a drive to get to them.

Why 95? Just curious.

Mines at 123k and did not have an easy life before I got my hands on it. I don't beat on it, but I don't baby it either.

Like Gorn said, a donor car is the easiest way to do it.

 

Gorn - I was thinking about just getting a donor car with how many parts I need from it. But as it turns out, I have miraculously found another 3.4l which I didnt think I was ever going to. So Im beyond happy about it. So luckily I wont need all of that now. Thank you, and Im still going to check out the articles for future reference.

MK - holy by coconuts you have a well focused attention span. haha.
I will really need a new tranny no matter which engine?? I thought 93-95, the LT1 still used the same automatic trans? (Im basing this off of reading stuff online, no hard evidence so I could be completely wrong. haha)
As far as why I wanted specifically a 95 (and now want my second camaro to be specifically a 95 LT1) here is a little info I found out about them.
"
The 92–93 LT1s used speed density fuel management, batch-fire fuel injection and a dedicated engine control module (ECM). In 94 the LT1 switched to a mass airflow sensor and sequential port injection. A new, more capable computer controlled the transmission as well as the engine and got a new name: powertrain control module (PCM). Where the ECM held its calibration information in a replaceable chip, the PCM was reprogrammable through the diagnostic port.
The early Optispark distributor had durability problems and a revised version was introduced with vacuum vents to remove moisture on the 1994 B-Bodies and in 1995 on the Y and F-Bodies; the vacuum vents can be added onto earlier distributors.[1] 1996 saw major revisions for OBD-II: a second catalytic converter on the F-body cars and rear oxygen sensors to monitor catalyst efficiency."

Now most people would probably say go for the 96, but I found out the 96 and 97 are temperamental about letting you fine tune them. So by a stroke of irony, the 95 is the best made LT1 that is also most easily tuned.

 

me thinks your thoughts are flawed. lol. i would go for a 96-97 depending on which interior i like. imo obd2 is a better system to deal with overall. oh and i do like the 97 interior better. most tuners that i have talked to like the old memcal ecm. i think more because its been used for so long there is a comfort zone but thats just me.