A-man930

iTrader: (2)

I'm planning on picking up a junkyard LT1 to tear apart/build soon after I get my '97 Formy. I was wondering if there are some specific years or models to avoid due to electronics differences etc... is there really anything besides the vented/non-vented optispark issue? Thanks guys

Formula350

iTrader: (3)

96-97 use OBD2, but if you're BUILDING a motor, that shouldn't matter, since you'll use all the bolt on parts from yours (timing cover, intake, Opti, all that stuff). Vettes use 4bolt, Caprice and Impala use cast iron head, as well as some having the 4.3L Baby LT1. I'd stick with 95+

A-man930

iTrader: (2)

Forgot about the 'vette 4 bolt So 95 and up F or B body 5.7L...

Javier97Z28

iTrader: (1)

You don't know what a 4 bolt main means do ya?

96capricemgr

iTrader: (1)

IMO the Vette 4 bolt mains does not make them more desirable as most think they are, I would avoid them just to avoid getting raped for no real benifit.

IMO the best motor to find for a build is a 95 Vette or F-body motor(Vette only if the same price). These will have the early thick casting lesser flowing heads most desirable for porting and a vented opti setup. The timing cover will lack the CPS hole you need for OBD1 but the cover can be sold to someone with an unvented opti setup so they can upgrade.

That said all the LT1 blocks are the same casting, even the 4-bolt mains. If just looking for a block not worried about extra periferals or core heads then a
94-96 Caprice sedan police or civilian(4.3L was the base LT1 was optional so make sure it says 5700 behind the drivers side head)
94-96 Caprice wagon LT1 was the base motor, rumors of a single special order 4.3L car out there, again you could check for the 5700 but it would be REALLY FREAK if you found 4300

The 93 and back intakes wont work with the 94+ fuel rails blocks and heads would be perfect though
94-96 Roadmaster sedan or wagon LT1 was the only engine option
94-96 Fleetwood again LT1 was the only option

Formula350

iTrader: (3)

Well, from my understanding the 4bolt handles torque a bit better. But yes, you can make any 2bolt motor into a 4, or even 6 if you plan to make ungodly amounts of power (as in running Nitromethane heh).

What's the benefit of upgrading to that timing chain cover? o_0

Irish350

iTrader: (14)

coming from someone who has to deal with emmissions, id say go with obd2 (so no 93-95)


ive never even heard of a 4.3 lt1....

Formula350

iTrader: (3)

It's called the Baby LT1. Can't use the 4.3L heads on a 5.7L and vice versa.

Well, I guess you might be able to use the 4.3 on the 5.7, but I can't see why you'd want to with the smaller valves.

A-man930

iTrader: (2)

Uhh, yea sure do. And I also know that doing a splayed 4 bolt from a original 2 bolt block would be stronger... thanks

I'm really don't need the heads or intake, but I guess having the correct (95 & up style) would be preferable. I really only need the block and bottom end, so if all the castings are the same...

Formula350

iTrader: (3)

Rods are different between the years, I don't remember which is better though. Someone else will have to chime in with that.

94Pontiac

iTrader: (4)

I think that 93-94 were pink rods and 95-97 are powdered metal rods...

96capricemgr

iTrader: (1)

Pretty much and the PM are considered better but the "pink" were the gold standard of OEM smallblock rods for decades so they are no slouch. That said, rebuilding stock rods will cost easily $160, for under $300 you can get some pretty good aftermarket rods these days si I wouldn't bother with the stockers on an engine build.



Formula350, the vented opti is more reliable and takes a different timing cover.
At the level most of us play at the "4 bolts are better" is meaningless because the 2 do the job just fine. I don't care what somebodies father told them about the 30 year old stuff he used to work on or anything else. IN THIS APPLICATION the 2 bolt is solid. Yes 4 bolt can be better but most of us will never need it.

That is something I missed earlier the b-bodies got the vented in 94.

Formula350

iTrader: (3)

Oh, yea I know about the vented and so forth, I thought the timing cover itself was just a good thing to upgrade to by itself, and couldn't figure out the reason Thanks.