LT4 Engine Swap (LT1 to LT4)

[Topless]

Ok, has anyone here dropped a complete LT4 into an OBD-I vette? I am looking to install it in my '92 (with 6spd), and boy do I have questions...

Computer? Can I run my '92 computer and leave off the MAF? Should I? If I switch computers, what else do I need to change/modify?

Any and all suggestions welcome. This will be a winter project, I am just planning the work. I am going to have the block freshened, and such, so any modifications while it is out and on a stand will help.

-Thanks

 

[93Rubie]

why do more work than you have too? Just put lt4 intake, heads, on with some roller rockers and you basically have a LT4. Stuff an lt4 hotcam in it and get your ECM custom tuned, while your at it. A lot cheaper and less hassle than pulling the motor to get a whole 30 to 40 extra horse.
Compression is only .1 higher than the LT1.

Why are you having the block freshened, from another post you said she had 127K on her??? GM designed the LT to be very durable and reliable. Is yours low on compression, low oil pressure, have other internal problems??? LT's that have regular oil changes should go 200K with no significant ill effects on internal parts.

If you do pull it and freshen it i suggest pulling out all the stops...Street Thunder magizine did a LT1 build, and punched it to 396 and had 550hp and made 450lb-ft from 2800RPM to like 5500 or something like that...Sweet.
You really want to go faster bolt on a blower and made some real big power!!!

 

[Topless]

I autocross under NCCC in Group II, so I have to keep the engine compliant with those rules. I could swap over the heads and intake, but was told that it was about the same amount of work as swapping the entire engine.

Sorry for the confusion, I am getting the LT4 freshened- the person I bought it from did not have it covered/sealed up. So, to use it I have been advised to pull it apart and look for condensation and what-not. And while I was at it, put in new rings and bearings.

I am doing this to build power, but there is absolutely nothing wrong with my LT1. (133K as of this morning.) I might have an opti spark going out, and for the amount of work to replace that, I might as well pull the engine. Last time I had the opti replaced, my vette was out of commission for weeks, and the mechanic (at a DEALER) used a prybar on the balancer. A mess of a situation that was.

 

[93Rubie]

I see, yeah you might as well just swap to an LT4 in your case.

 

[wickedlt4ce]

The engine itself is a direct drop in. I'd go ahead and just get a donor LT4 harness and ecu or get a aftermarket harness and ecu to do the job right. Plenty of aftermarket places to go for this.