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Discussion Starter · #1 ·
Hey guys what's up? I have a 94' Caprice Classic with an L99 V8 and I have found several decent Lt1's locally on Craigslist, and I was considering making the swap.. My 4.3 Litre, tranny and chassis on my 94' only have 60k, but I want more performance.. What all is to take into consideration? I have done some research myself, but any insight would be greatly appreciated! Feel free to fill this thread with random Lt1 swap links! I'll read everyone.. Thanks!
 

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I would do a Transgo kit at the same time as the tranny behind the L99 was setup a little lighter duty with smaller servos and boost valve, maybe some other things to but a shift kit will get you a good step in the right direction.

Use the LT1 injectors, get the pcm reprogrammed for the swap don't try just reusing the pcm from the donor.

The L99 fuel pump was smaller, if in good condition and the LT1 left near stock it will work fine.

Do you know if the car has the 7.5" or 8.5" axle? If it has the 7.5" the LT1 can tear it up if you have traction which is unlikely without a posi so this is something that would eventually need attention. The 7.5" axle was used in some civilian L99 cars.

What are the engines you are looking at out of?

I did this swap but it has been a little over a decade so you will have to ask question to get me to remember everything.
 

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Discussion Starter · #4 ·
My car has the 8.5" rearend and just put a new fuel pump in it (naturally).. I have found several and am emailing, calling and texting all of them lol,, Some are out of Camaros, some Impalas, Roadmasters and two are Corvettes.. So a bigger fuel pump and shift kit so far? making my list, to see if this fits my budget.......
 

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8th Gen Antagonist
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Stick to the B-body engines, caprice/impala/roadmaster, the vette/firebird/camaro engines were set up a little differently, and accessory routing could be an issue.
 

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The accessories from the L99 can be reused.
A new stock L99 fuel pump will feed the LT1 till you do internal modifications, heck depending what you bought many sources probably just use one replacement PN so you might have gotten something LT1 sized.

If considering f-body or Vette engines consider they are likely more abused and will command a much higher price, also possible hassles like the unvented opti and having to swap the timing cover and cam because of that.

Mechanically the vette and f-body motors really don't have much advantage and a LOT of the HP difference was in programming not parts and the cam in those compromises lowend torque unnecessarily IMO that was done for the f-bodies weak axle.
 

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Discussion Starter · #7 ·
Right on.. Thanks, these are all things i need to know.. I found on with 60k on it out of an actual Impala. He has the computer and harness.. but i`ll need to reprogram I guess...
 

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8th Gen Antagonist
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Ah, forgot you could just swap the accessories, I'm always thinking about swaps into older vehicles... The vented opti became standard in 95 on F and Y bodies.
 

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let me see if I can find my brother post, he did the l99 to lt1 swap for less than $850. That inclueds the price of the motor!
 

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you don't need a harness.
It really is a direct swap.
 

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Discussion Starter · #11 ·
Thanks to eveyone posting.. I have narrowed down my search.. I found an Lt1 out of a 95 Impala with 60k on it.. It has no intake (will mine fit the 5.7?) but he does have the throttle body, injectors and everything else minus all the assesories which I already have.. He told me to make an offer (hate it when they do that lol) .. I offered him $600, he told me $750.. What do you think? Am I missing anything moneywise? Just drop it in right? Maybe a shift kit, maybe a fuel pump later...........? What else?
 

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After my brother did his swap, which his was a l99 in a detective car so had the bigger rear end, his tranny only lasted two weeks!:eek:k3: But I think that had something to do with how he drove it!!!
 

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Discussion Starter · #13 ·
Yea my transmission man said the same thing as Dwayne J.. Transgo kit, bigger servos and boost valve should get it.. Hey dylan702 would you try to post a link to your bros thread on the swap please..
 

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yea I have been trying to find it for you cause he had it step by step including who he had do his computer for the injuectors. but he was on 4adrive which went down a few years ago then came back up, now he cant find it. I know if you google his screen name you will find alot of his stuff, motorman702!
 

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Your intake will work fine. There are several different castings but they are a year to year thing not an L99 LT1 thing and any of the 94-97 LT1 intake is fine, the 92-93 ones had a different fuel rail crossover arrangement which makes them harder to use.

Here in Wisconsin I wouldn't pay $600 for a used LT1 much less one missing the intake.
Does the guy think it is "special" because it is out of an Impala or what?
Pricing does depend on where you are.
 

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Around here that motor would be worth $200-300. For $750 it had better not only be 100% complete with wiring harness, but some recent work as well, or at least mated to a transmission.
 

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Discussion Starter · #17 ·
Well I'm from the Show-Me-State of Missouri and I would have to see that to believe it, but "here" they go anywhere from $300-$1000.. I found one with 160k for $400, one with 130k for $600, but the one I want and the one I was talking about had 60k on it.. He told me $750, I told him $600 NO more.. But anyways I was trying to get the swap done for right around a $1k.. And i'm talking everything..
 

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Creepy Ass Cracker
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try a junk yard.graiglist sellers want too much.ive called a couple of our local yards looking for a core engine to get this Fat Girl of mine rolling a bit faster.highest price one was 500$.craigslist prices start there.Stick with Dwayne,he's on top of these engines.
 

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Creepy Ass Cracker
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mine was born an LT1 though.but,i bet yours isnt on mother natures weight loss program like mine.i got the beginning of a sunroof in the floor:gaah:
 
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