midge54

So i have the LT1 hooked up to my transmission and down in the car. Now im starting to second guess how i want to do this car after reading into it. I originally was going to wire up the fuel injection and run full fuel injection, but seeing as this my 86 is a carbed car there seems like there is going to be a decent amount of work and money to get this thing running fuel injection. Plus im not sure i want to do the wiring myself and it will cost a small fortune to get a stand alone harness. On top of that it will probably need new injectors, an optispark, pcm program, fuel system swap or modification and who knows what else. So ive been looking into maybe doing the GMPP carb LT1 intake and just running carbed since the car is set up for carb anyways. I know i will need to add timing system to the engine and saw summit has a block of plate for the optispark that also adds the timing tab. But what about the balancer, are there any LT1 specific ones that add the timing marks, and if so does it just bolt on to the hub at the end of the crankshaft. I know the hub isnt keyed so if i had to change the hub to a keyed how would i make sure that the length is right since i am running caprice accessories. Ive also thought about just going back to gen 1 sbc but ill be losing the aluminum heads and the power of the LT1 seeing as the lt1 has cc503 cam and chevy 1.6 full roller rockers. anyones input would be appreciated

Citation X

Love mine. Makes power up to 6500 rpm. No need for timing marks. Time by ear . I did put an indicator on my distributor so I could see how far I'm moving it when advancing or retarding it.

midge54

im not sure i could do it by ear although i would love to save the money by not having to switch hubs and balancer. if i went with the opti block off plate would i still be able to use the gear driven water pump or would it block that. Im seriously thinking about going carbed LT1 since my LT1 is already built but i really dont want to deal with converting the car to fuel injection

Citation X

Should still be able to use the pump. What carb do you plan on running?

Citation X

I haven't seen a sbc hub in different lengths. I think they are the same.

midge54

im looking at a edelbrock 1406 carb. im talking about the piece that slides on the crankshaft that the pully bolts to, are they different lengths or are the accessories different depending on car. cause i remember seeing you have to keep caprice with caprice, f body with fbody etc cause the belt wouldnt line up

Citation X

Ya you do but I didn't think that was the reason. I may be wrong on that though. Its been almost 15 years since I did my swap hah.

Citation X

You decide on what timing system your gonna use?

midge54

thats one of the things im trying to figure out. I want to have the timing marks to go along with the distributor to time it like a standard small block, and am considering going with the gm block off plate that has the pointer then going with this hub http://www.summitracing.com/parts/pfs-80030

Citation X

I used a msd distributor with mechanical curve that I welded open, the msd 6al and the electronic curve box. I think it is all in one now and have a programmable curve option too. I plugged the hole for the opti and put the distibutor in the normal sbc spot. Was no need for the hub then. If you go that route I would go with a holley so you can have more control over jetting.

midge54

i was thinking of going with a vaccum advance distributor, something like this http://www.summitracing.com/parts/sum-850001r

i still need a crank hub to run the accessories and im concerned that if the hub i showed doesnt bolt up to the piece on the end of the crankshaft right my belt wont line up

Citation X

I would bet it lines up. LT's are all over the yards you could probably pick up the accessory drives cheap.

midge54

i found a keyed hub on summit that specifies that it is for the 94+ impala caprice with lt1 so that should be the same length as what i have now

88IROC-USA

Carbed LT1s are pwn dude, I say go for it!

But don't run a 1406, that's a p.o.s.

Dragster Racer

I am wanting to do a modern LT swap. Something 2010 or newer. If the Wiring harness, ECU comes with the motor, how do you tie it into the existing systems? Speedo, Tach, Temps, AC controls, etc? Are there adaptors or do you have to wire individually each thing on the third gen into the new harness?

Bow_Tied

iTrader: (1)

It is more work to get the FI in place but you will enjoy it long term. If you are worried about the opti-spark you could eliminate it with a Torqhead kit (https://www.torqhead.com/why-24xlink-components.html) and then you'd have the option of LS tuneability.

1986BANDIT

you need a custom stand alone harness for the new lt1(you mean the most recent one im assuming) then you will need to talk to someone like hawks third gens,detroit speed or similar to see what else you need to do for the lights ,guages and everything else.

RS Chris

The new model LT is only a few years old, 2016 or so. I'm not sure how much swap parts are available right now so that will be a big issue. Wiring will be THE biggest pain with 2-3 decades of technology difference. A stand alone ecu with a digital dash (racepak, holley, etc.) would be the best way to display engine vitals. If you're comfortable fabing and re-wiring a car, then go for it. Otherwise might be best to wait for swap specific parts to come out.

Dragster Racer

If i got the wiring harness and ecu with the motor and connected it to a digital dash does this eliminate the existing electronics altogether or are there still connections to the existing system that would have to be made?

1986BANDIT

its a long arduous process that is never cheap and definitely not done in a weekend or two.when you need to chase down individual(expensive and rare) items to piece together a modern drive-train into an older car it gets expensive and time consuming.check threads that have done similar swaps and glean information for your own use.
ideally IMO the best thing to do is to buy a wrecked 1998 and newer z28/trans am/formula and transfer everything over(this way the drive train is usually not blown up OR DAMAGED because the car was scrapped because of a wreck and not because of mechanical/electrical issues).the entire dashboard,console and gauges,wiring and ecu,transmission,rear end etc can be used in a third gen with some creativity as well.

Jesse Dean

Hey I realize this thread is a few years old but I'm actually doing this swap now I'm swapping my 3.1 liter V6 out of my 3rd gen for a 95 LT1 out of an f-body and I'm converting it over to carburetor so I don't have to fool with the computer.I have the optispark block off and distributor on its way I have the new intake and a Holley 750 CFM with the vacuum secondary as a car but I'm wondering if you ever finish this build and do you have any tips tricks or pointers for me this is my first engine swap

1986BANDIT

#1 PRE LUBE the engine before starting it for the first time when you have it together.

cleanliness and organization are absolutely necessary.
dry fit everything to deal with issues before its together and take pictures,make notes.
use good gaskets,make sure all threads are clean and use sealer on the ones required.
torque in steps using the right pattern and never over torque.
check all clearances of your crank,rods,rings etc and make more notes.
the best machine shops make mistakes so better to check while its easy.
if you are using an old style vacuum secondary hei make sure you use a melonized gear with the roller cam in the LT1,
also consider bumping up the cam size while its all out and accessible.(lt4 hot cam or better)

a cam change is SUPER easy now and can be worth 50+ horsepower ,its a pita later .
this isnt an opinion,a cam change while on the stand is cake but in car is a massive pain in the a$$