Engine SwapEverything about swapping an engine into your Third Gen.....be it V6, V8, LTX/LSX, crate engine, etc. Pictures, questions, answers, and work logs.
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I have an LG4 in my '85 Z28 and it has 150,000 on it. It still runs great, doesn't burn much oil at all. However I know I'm at a significant loss for power and I 'm sure the internals are sloppy now. Auto Zone offers reconditioned 305's for sale if I trade in my old engine. Has anyone done this? Would I just be buying the same factory horsepower and torque? I don't want a 350 because I don't want to change the computer. Please advise.
That's not exactly the advice I'm looking for, but thanks anyways. Has anyone else done this engine swap before? I'm not going to heavily mod this car, that's for the old camaro.
I may not meet your qualifications since I haven't put an Autozone engine in my car. But, I think you should reconsider your ground rules.
A rebuilt 350 may actually cost less than the 305. You could bolt in the 350 will all of your LG4 parts. To get the most out of it, you'd want to tune it, but a different computer probably isn't what you'd need - more likely things like secondary rods & hanger, exhaust some day.
You'd be happier overall with a 350.
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82 Berlinetta, orig V-6 car. Rescued w/86 LG4/TH700R with all harnesses, sensors, ECM, etc. 2.73 open. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LB9 w/ZZ3 cam, exhaust, paint, etc.).
57 Bel Air, my 1st car. Currently 396 .030 over, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & shift kit, 3.08 10-bolt, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.
Stop befor you get hurt. The Autozone engines are remanufactured and have all kinds of clauses to help them get out of honoring the warrenty. A friend of mine put one of their 350's in a truck and it died within 3 months. He went to claim the warrenty and they told him no because he had an aftermarket breather on the valve cover. Can you believe that!? Go to www.sdcp2000.com and check out their goodwrench crate engine. It has a 50000 mile unlimmited warrenty and cost 1289 bucks brand new. I just installed one in my camaro last week. It is cheaper to go with that motor than to rebuild or buy a replacement 305. Besides, everything from the 305 bolts on perfectly and the 350 is rates at 100 more hp than the lg4. email me if you want some details, I used to have the weakly lg4 myself, but it did last 215,000 miles!
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1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock Tes Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
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"I used to be a Mustang Guy! I didn't know the power of the dark side!!"
RustyZ, I agree with chris. the gm crate motor is the best deal and you will be much happier with a 350. I would do the same thing but my 305 only has 80,000 on it so I am doing a few mods. but If I needed a new engine it would be a Gm crate engine hands down. If your 305 still runs ok, save up some more money and get the Gm 350 . You won't regret it based on the 100's of posts I have read on this site....bob
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91 camaro RS convert
t-5
open element air cleaner
TBI spacer
Flowmaster muffler
3.42 Torsen posi
RustyZ ,i agree with everyone else.I have heard nightmare stories about autozone replacement's.I'm looking at swapping out my lg4 this winter.I talked to jeff at scoggindickey and he was very helpful.The tech line # is 806-798-4108.A 350 crate would be the way to go,if you're really stuck on getting another 305 ask about a late model caprice 305 it's gm part# 12518296 ,the only thing you'd have to change would be you're flywheel since this motor has a one piece rear seal.Hope this helps.
It's rusty Z again. If I were to change out the old 305 for the GM 350 how much of my "old" stuff could I use, carb/manifold, water pump, starter? The fact that my computer and electronics would be ok has persuaded me to lean towards the 350! Has any one here had any major problems with the switch? Pollution or any other systems? Please advise.
Originally posted by rusty Z: It's rusty Z again. If I were to change out the old 305 for the GM 350 how much of my "old" stuff could I use, carb/manifold, water pump, starter? The fact that my computer and electronics would be ok has persuaded me to lean towards the 350! Has any one here had any major problems with the switch? Pollution or any other systems? Please advise.
See the 3rd response above.
About the only thing you'd have to insure is that you have the correct flex plate; i.e., you currently have a two-piece rear main, and unless your new engine is also two-piece, you'll have to get a new flex plate. If it doesn't come with the harmonic balancer, you'll want to get a 350 piece.
Originally posted by MilehighBird: RustyZ,
If you switch to the 350 you'd probably want to save yourself some trouble and get a knock sensor for a 350 as well.
Check what you have, but I believe LG4's didn't get knock sensors until '86. But, if you have it now, get a sensor & module for a 350.
Thanks for all of the responses guys. I have not changed a motor before and appreciate all your insight. When I purchase the 350 can I buy my flex plate from the same vendor? GM? As for a knock sensor where can I look on the motor to find it. thanks!
On a funny note about the Autozone engines. LOL The guys at my local Autozone actually recommend the GM Goodwrench crate motor over their own.
Regarding the 350 Crate motor... I don't need no steeeeeenkin' computer for it, do I? I was hoping I don't... BUt... Then again, I do have an 86 LG4, computer controlled Q-jet and HEI. If I got the 350, could I still use the computer for the carb and the distributor 'til I got a vaccuum advance HEI and non-comp carb? Also... About that flex plate. Having the 86 LG4, will I need a different one?
Also, anything else you can throw at me would be lovely.
The knock sensor is located in the passenger side block drain hole, under the exhaust maniford and in front of the starter. If there's a can with a wire going to it in that location, you have a knock sensor. If just a pipe plug, you don't.
You really have to know exactly which "crate" motor you're getting to know if you need a new flex plate. Some have one-piece rear seals, some have two-piece. You can figure that out when ordering, and have them get the proper flex plate for you while you're at it (some crate engines come with the flex plate).
Again, the LG4 computer will operate a 350. You don't "need" a computer to run a crate 350, but if you "need" to pass emissions testing, you most likely "need" a computer (although there are exceptions for now - don't count on it forever).
OK... So my ECM will work... But I do eventually wanna yank that biddy out of there. I wanna put the Edelbrock 1406 carb on there with the 7101 intake and a new vacuum advance distro and remove all vestages of crap that reduces performance. But I guess for now, that'll operate the carb and distro.
But about the flex plate. The 350 crate motor on sdpc2000.com has a two piece rear seal... Now what do I have on my 86 LG4? Can I use my current flex plate?
Originally posted by GilmourD: OK... So my ECM will work... But I do eventually wanna yank that biddy out of there. I wanna put the Edelbrock 1406 carb on there with the 7101 intake and a new vacuum advance distro and remove all vestages of crap that reduces performance. But I guess for now, that'll operate the carb and distro.
But about the flex plate. The 350 crate motor on sdpc2000.com has a two piece rear seal... Now what do I have on my 86 LG4? Can I use my current flex plate?
You have a two-piece, so you can use your current flex plate.
Keep everything you take off in a box in the attic. You're bound to be sought out by the EPA sooner or later.
I beleive that the only mod you will need is to change the jets and metering rods in the carb... I would recommend rebuilding the carb while your at it...
Didn't one piece rear main seal small block production begin in '86? The one piece design is a good one and should be sought after.
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'85 Sport Coupe V6 T5(bought new)Putting in 88 350 TPI/AOD and a bunch of 88 IROC and aftermarket performance parts now.
86 IROC 305 TPI AOD
(selling after Sport Coupe rebuild is done)
Originally posted by Glen: Didn't one piece rear main seal small block production begin in '86? The one piece design is a good one and should be sought after.
Yes, it did, but not all '86's (such as LG4's) received the one-piece. Didn't get roller cam or different-angle intake manifold bolts, either.
The point is, if getting a crate motor, make sure you have a flex plate that will work with it.
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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.73 unlimited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LB9 w/ZZ3 cam, TBD heads, exhaust, paint, etc.).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & shift kit, 3.08 10-bolt, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.
hey Rusty, I did the switch and I love it--and thats no bull, that 350 gm crate is awesome, the switch was cake--and I have to tell ya, I was nervous---but for nothing---my rs gets it and then some, also my new 350 gets way better gas milage then the last 2 305's Ive had and that is fact!!! Just do it and then pat yourself on the back for being a genious..
I was looking for cranks and every one lists the 86 block as a 1 piece rear main but, not as a roller so perhaps the 86 is a singled out block . (1 p. rearmain, no roller)
Something to ponder:
I have a friend with an 85 IROC that needed a new engine. The Chevy dealer would not honor the warranty if he put a GM crate 350 in it because it was not offered in the 1985 camaro line. He ended up getting a crate 305 instead. It's worth checking into.
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'85 Sport Coupe V6 T5(bought new)Putting in 88 350 TPI/AOD and a bunch of 88 IROC and aftermarket performance parts now.
86 IROC 305 TPI AOD
(selling after Sport Coupe rebuild is done)
alright, i may be the dumbest person here, but i have a 305 TBI, in my 90 bird. Engine option LO3 (go ahead and laugh). If i were to get a gm 350 crate motor, could i keep my tranny?
alright, i may be the dumbest person here, but i have a 305 TBI, in my 90 bird. Engine option LO3 (go ahead and laugh). If i were to get a gm 350 crate motor, could i keep my tranny?
I got just one guestion. Most of you here only know about when the engines changed beacuse you heard it from someone eles.I have two suggestions, 4th gen engine and trans, such as the LT-1 and T-56(There are instructions on how to do this at this site, this is what i am doing.) or go ask the guys at thirdgenparts.com. You can net a wreacked camaro for around 1500.
-Tom
[This message has been edited by camaro6spd (edited January 04, 2001).]
