Hey guys,

I am looking to pick up an LT1 T/A or Z/28 come spring-time and I had some questions for the veterans here. I'm on my second 3rd gen T/A now, and it's giving me nothing but trouble. So in the spring I am selling it and buying an LT1 4th gen, so hopefully I can enjoy the summer in the car instead of under it.

What years would you recommend, and which to avoid. What are some common problems on LT1s? Any mechanical difference between Z/28 and T/A's? How are the tops on the verts, do they leak/close poorly? Do T-Tops on 4th gens leak like the 3rds? I hear the LT1s are a pain to work on since half the engine's under the cowl, is this as bad as the 3rd genners paint it out to be?

BTW What is the cheapest I can get an early LS1 with decent miles?

Thanks for the help,
-Max

 

As far as the 4th gen goes, they aren't much harder to work on than a 3rd gen. Yeah, the engines sit under some of the cowl, but most of it can be reached by rolling up your sleaves. It's not like there's a distributor back there or anything. As far as woes on the LT1, the imfamous Optispark is easily the worst. It's not really hard to change, but it takes time and it isn't cheap (not like the $20 cap and rotor for a SBC). The mechanilcal differences between a TA and Z28 are negligable, it's mostly cosmetics. As for picking up a cheap LS1 car, you can get them for $10 grand or even less, but expect the miles to be high. Price goes up for fewer miles.

 

As far as the leaking issue I can address the convertible. Mine has a cheap replacement top on it now and it only leaks whan I am washing it if i spray the hose in the right spot. I just replaced my opti and spark plugs and wires and hoses. It's not easy but not impossible either. Just find a buddy with small hands if yours are not.

 

95 is probably the best year of lt1 4th gens
reasons:
optispark is vented (so are 96-97) to help keep moisture out and make it last longer, you could though convert a 93-94 to a vented (not sure how expensive or what you have to do though)
95 is last year of obd1, which is better for working on or something, ask around for this one
95 is last year for hardened pushrods

some other quick facts
93 are speed density, meaning no maf, take it for what you will
93 have 22lb injectors, 94-97 have 24lb
96 start of obd2
96-97 (and some very rare 95's) have dual cats which is the supposed reason for 10 hp leap

o, and my dad has a 95 camaro, no leaks in the t-tops although it only has 60k miles so
but still, i heard 4th gens are waay better than 3rd gens for preventing t-top leaks

oo, and i have seen 98 or 99 ls1's go from 8-11 grand or so

hope this helps man

 

aah yes, one mor ething

95 is the start of the 5 speaker bose system (93-94 had 3 speaker bose) if you got tat option of course
and 97 start of the monsoon system (kickass)
monsoon is like a really great head unit (automatcally raises and lowers volume when you get on and off highway or something, sort of a neat feature )
it also has 1 or 2 amps, can't remember, that power 8 speakers (10 in the firebird i think)

 

two common problems that i know of on the lt1s is the infamous "intake oil leak". it is noticable by a small amount of oil dripping off the back of the block. nothing to destructive, just need to watch your oil level. it can be fixed if you don't mind removing the intake.

another one is the crappy steel driveshaft that isn't very well balanced. some are better than others it seems. it isn't a problem, but sometimes you'll get a vibration between say 70 and 90 on the highway. this can easily be fixed by buying an LS1 aluminum DS (typically sold for about $150 or less or a 1le shaft from any year 1le car even third gens), or an expensive aftermarket shaft for $300+

as for problems working on them, the biggest hassle in routine maintenance is the spark plugs. a typical plug and wire replacement takes about 4 hours your first time. tips include removing the alt. and pulling the passenger motormount bolt and jacking the motor up 2". i did it myself, taking my time, and never having done it, and it took me 4 hours.

 

Well everyone has pretty much everything covered here except 1 thing. 94 Z28s are the fastest of the 93-97 4th gens

 

damn, how did i miss that one?

 

Thanks for all the help guys,

Well I figured I should stay away from 93-94, heard about their crappy Optis a while back. Kinda sucks that maintenance is so difficult, I can change my spark plugs in half an hour on my TA. (BTW Is it so cluttered underneath, that you can't get to the spark plugs easily from under the car?) I hope it doesn't take three hours for an oil change

What years does the intake leak, and how hard is it to change the intake gasket, easier then on 3rd gen TPI's I would guess?

I like the 5-speaker Bose, and the Monsoon sounds even nicer.

From just taking a quick glance at prices on autotrader, it looks like I'll be in the market for maybe an early LS1 T/A (Damn, they are much cheaper in Texas then here in Jersey), a 97 T/A, or a 95-96 vert.

Also most 4th gens aroud here are autos, is it the same 700R4 that's in the 3rd gens?

Finally, most important, are 4th gens known for any particular electical gremlins? I had those problems on both my cars and I don't want to deal with it again.

Thanks for the help,
-Max

 

Get a 95, I'm not biased, can you tell When you find a car you might think you want to buy, take it out and do a few full throttle runs. Punch it at about 40-45 so you can pull through second gear. If you get any stumbling or hesitation don't even bother with it and go look some more. I know the problem may be simple, but I have heard so many horror stories of people with ignition problems not being able to find the culprit, or finally fixing it after spending close to a grand in parts and time.

I don't care what anyone says, fourth gens are so much harder to work on than thirdgens. I had a 91 Camaro, and it was a walk in the park compared to my current one. There is absolutely no room in there to work, and after working on my car for years now, I am convinced that GM hired a team of retards to design the fourth gen engine bay.

 

Crappy opti? I just turned 80,000 miles on the odometer with the original opti :knock on wood: .

The infamous intake leak leaks on every year LT1. Some leak, some don't, but I believe it has happened thru all 93-97s.

 

it is essentially the same thing...
700r4 with an electronic part to it and a different valvebody
the electronic just makes nice smooth part throttle shifts then on wot it shifts a little firmer (you know, for your granny drivers then you're more "enthusiastic" drivers )
also, it is either weaker or just isn't up to snuff under the power of the lt1 (i've heard some last and some have broken at like 60k, sort of a hit or miss)
i would go 6 speed (that's just me though) but beware, they are fewer and fa between all the autos, also the 6spds are much tougher, which you might already know
also, fyi, the auto is called 4l60-e
also, in 93's, it is just the 4l60 (700r4 with different valvebody, no electronics yet)