Who has done it and what did you use for the lsx wiring harness? HOw did you adapt the lt1 harness to lsx?
Or did you just replace it with a lsx harness?

What else is needed for a lsx swap I.E- engine parts, electrical?

I will add as needed

 

Funny how these thoughts cross our minds when bored...curious as well... I know you will need a ls1 crossmember

 

yep that for sure, but what about the harness? Keeping the stock one to work with all interior.

 

I helped a friend put a H/C LS1 in his '97 ss about six years ago, here's a couple of things I remember...

You'll need not only the LS1 k-member, but also the steering rack and steering shaft. The input on the rack sits in a different place, and causes interference with the steering shaft and headers. Lot of different options on wiring. My buddy chose the cheap way, which is also the most difficult. He went to the library and got wiring pin-outs for his '97, and then a '98 and did the the 'ol cut-n-splice dance with the two harnesses. Now a days, there is several companies that will make you a complete plug-n-play harness. Althought pricey, they'll make the swap a breeze.

 

i would say ls1 pull out tranny of your choice, you can make the lt1 cross member work, just need to make motor mounts, or im sure there is someone who makes the adaptors. then an ls1 computer and harness and your in bussiness, probably some fuel line modification involved aswell im sure it would be pretty straight foward

 

Lol nevermind guess you have to have a kmember

 

fugg that go with nitrous man. I think we get better stock cam fuel economy too in the LT1 (can anyone confirm?). I've contemplated the same thing about ls1s but it has to be A LOT of work. Probable more so than its worth. And its a more expensive engine to run. With nitrous u can keep a warm cam in our blocks and retain good fuel economy.

 

my lsx plans are l33 turbo but that's a few years away, still enjoying the lt1

my list is not engine specific, rather if i choose a LS type engine, what do I actually need in my LT1 fbody. took me a little research over the last few months. Here's what I have so far:

electronics:
ls1 pcm -pref 411pcm so you can get the hptuners, efi live etc
ls1 wiring harness (lot's of good writeups on here)
ls coils and brackets/connectors
98 camaro coolant temp sensor -3 wire

engine/trans
ls1 fbody oil pan/pick up/windage tray/dipstick
ls1 front accessories
ls1 t56 with bellhousing/mc/clutch/slave
99? corvette fuel regulator (for the return)
air/lid setup
ls1 headers

chassis:
ls1 kmember, but probably umi road race version for me
hood / mod to clear ls1 lid setup
ls1 steering rack and intermediate shaft
t56 ls1 cross member (again maybe UMI torque arm with integrated cross member)

 

I don't think the LT1 gets better mpg than the LS1. I seem to recall people saying on a stock A4 LS1 they can pull 25mpg highway. I can squeeze 22 out of my mostly stock car if i use the cruise control the majority of the time.

 

I recall seeing old factory spec labels flaunt 28mpg highway.
I dont know about the A4 but I dont think it flaunts the same overdrive some of the later years in M6 do. which is .50@6th gear. From I think 95' onward.

I sometimes shift 1 to 3 to 5 in the city...it really really helps.
The best ive seen gm post about LS1 equiped cars is 24 or 26 i think.
I'm not saying this as for certain on the numbers exactly (anyone confirm if they have more concrete)
My overall impression is the Lt1 renders better mpg and all later years started to deliver less and less but with more HP in return.
LSx is god. but Im definitely torn about between transplanting it vs. injecting nitrous. but hey thats just me.

would be lovely to do the transplant and run nitrous. scary thing is lsx are usually aluminum. so the LT1 comes up champing again...as its iron thru and thru.

 

All you guys want to swap to LS1 lids, LS1 PCMs, converting SBC cylinder heads and intake manifolds and all this BS. If you want to do all that, just buy a LSX or a SBC.

I swapped a LQ9 6.0 into my 97 WS6 and here is a list of parts I needed
-Motor
-Transmission
-Accessories
-LS1 F body engine harness and PCM (I used 2001)
-LS1 F body heater hoses
-1998 Corvette fuel filter (has built in pressure regulator)
-LS1 F body headers and Y pipe
-LS1 F body K member
-LS1 F body radiator hoses

If you are using a T56, the LT1 trans crossmember will work. If you are using the 4L60E, neither factory crossmember will work. The LT1 crossmember is too far forward for where the mount is placed on the LS1 4L60E. The LS1 F body crossmember will not bolt to the floor of a LT1 car. I had a tab added to my LT1 4L60E crossmember, and it now works on both.

As for wiring, I used ONLY the LS1 F body harness. I did have to go to the junkyard and get one connector which was the black flat 4 pin connector that goes to the interior harness. I just cut one off a V6 car. I didn't want to rob it from my LT1 harness, that way I could sell the LT1 harness and recoup some money. There are schematics on this site to repin the LS1 harness to be plug and play with a 96-97 F body. You change NOTHING on the car wiring.

In my opinion, it would be a worthwhile swap if...
A) If your LT1 motor and trans have high miles and/or are worn out
B) If your LT1 car is in better than average condition (a lot of LS1 cars are just as worn out as LT1 cars these days)
C) You don't already have all the bolt ons for your LT1. Less money invested means less money lost that can be put towards parts for the LSX that you were going to buy anyway for your LT1

Other than repinning the harness connectors, the whole swap is just changing parts. It's not hard.

That said, my LT1 had a stock short block, my heads were used up from being fixed so many times in their life, my trans was tired, I didn't like the converter I had at the time, I wanted to switch to a 6 speed, etc. So after having a LS1 car for a DD I decided to do a swap in my 97.

The motor was this:
-LQ9 Short block
-Untouched 243 heads
-AI 231/235 cam
-Patriot valve springs
-Comp pushrods
-Untouched LS1 intake
-Stock ported TB

The car had a T56, 12 bolt, and a good clutch. The only weight taken out of it was the AC compressor, lines, and condensor, and the spare tire. First and only time I ever took it to the track it went 7.30 in the 1/8 mile. Then I found a killer deal on my 408 and got that. No doubt it would have gone faster with some suspension and some tuning. I don't think that's too bad for a motor I had $2,500 in building from scratch, on what was basically shake down runs.

 

what's diff between Lq4 and Lq9....which of the LSx engines is the thriftiest?

also which delivers best fuel mileage just out of curiosity.

 

Answering myself and to anyone wanting a rundown on LSx engines. Here u go;

http://en.wikipedia.org/wiki/GM_LS_e...Vortec_engines

confusing but def answers many questions.

It looks like the thriftiest may very well be the LQ4/LQ9 lineup.

 

The LQ9 has flat top pistons, the LQ4 has dished. The LQ9 is basically a LS2 with an iron block

 

I wouldn't mind doing the swap on an old Camaro, Chevelle, Nova...they have more space to work with. But on an LT1 Camaro/TA, I think it's more of a hassle needing so many parts..minus well put all that money on the LT IMO...

 

LS1 cars are getting pretty cheap these days.

Wonder how long until the feasability of a swap is questioned...all that work when you can just pick up a decent condition LS1 f-body for cheap?

 

correct. i believe the lq9 makes more power but the lq4 is better for spray

 

No...

 

Hey man are the LT1 accessories bolt-ons to the LS1 or do we need all LS1 acessories?

 

If/when my LT1 lets go, this is what I will be doing. Maybe a turbo too