I'm struggling to decide which way to go on my trans am I just bought. 1986 ta t top lg4 5 speed. Has 130,000mi on it and original powertrain. Pump the pedal twice and hit the key and it fires right up without missing a beat. But I have a brand new lt1 with cc503 and 1.6rr that hasn't even been started yet. My dilemma is it worth keep the original lg4 in the car and doing some slight mods to it or yank the 305 and put the lt1 in. I'm really only going to drive this thing very rarely so it will be lucky to see 1,000 miles a year, and I'm not planning on dragging it or anything like that, just take a nice weekend cruise in it every once and again. So in the long run which option is better the original 305 or the lt1

 

I say do a swap when/if the 305 breaks. If you're not worried about power then leave it for now. It's not like it'll be worth more stock, but it'll be worth more unhacked. Also I'd look into that carb, all quadrajets that I've had only take maybe a 1/4 pedal push to close the choke and squirt a touch of fuel to fire up nicely. Two pedal pumps is dumping a lot of fuel. If they've been sitting for a while it may crank longer but that's the nature of evaporating fuel out of the fuel bowl.

 

It has a new edelbrock carb on it and I just pump pedal twice before turning the key

 

In that case there's no point in worrying about keeping it an LG4 for originality sake. I say swap in the LT1 whenever or if ever the 305 goes down.

 

i'd swap the LT1 in... once you have it running you will wonder why you even thought to do otherwise..

 

So in the long run there will be no difference in value by keeping the original lg4 's restomodding it with an lt1

 

Done right the lt1 swap may increase the value a little but that increase will be offset by the cost of doing the swap right. If your looking for future values, I'd say in the far future the lt1 would decrease the value since it's a bit of an odd motor and the Ls and new lt platform are taking over.
For a cruiser I'd do a full exhaust, intake, cam, and a little head work to the lg4 and enjoy it.

 

value?
what's that?
cars are meant to be enjoyed and driven..

 

There is NO "VALUE" WHATSOEVER in leaving a LG4 in it.

Whether changing it to a LT1 would "increase" its "value" is a horse of a different color.

I think it's safe to say though, that as pitiful as the LG4 is today compared to other cars on the road, where a Kia minivan can DRILL you at will, that just about ANYTHING that will give the car some pep will add "value" to you as the driver, if nothing else.

There wouldn't be any point in keeping a LG4 for "originality" even if it was as stock as it could be after that many miles. Nobody is going to want to be reminded that such a thing even existed, let alone pay extra to get that.

That said though, the LT1 wouldn't be my swap choice. It's a real "fragile" kind of motor. (not the short block of course, rather, the electronics and such... not likely to be readily maintainable far into the future) I'd sell the LT1 to somebody that needs it and use the cash to buy a LSx motor of some sort.

 

i can tell you for certain an lsx swap is not gunna happen. The LT1 i have is complete top to bottom new and ready to drop in as soon as i get the harness finished for it. By selling the LT1 to go with an ls id still need 2-4K to try and even get an LS engine and get it in the vehicle, and the wife wont allow that much to be spent after putting over a grand in the LT1. i want to retain the T5, so at least with the LT1 i can get a gforce case to stop case flex and just bolt it behind my LT1.

 

Get a LT-1 swap to carb manifold and make it easier... Uses your existing carb and HEI distro.
I don't know what else is needed, but GMPP has the manifold- I was thinking about going this route, too...