kbar

Hi guys, I am looking a swapping an LS for my stock 350 in my 1975 C10 2wd. I got a buddy hooking me up with everything I need for the truck for a good price. I just have a couple of questions that I haven't read/googled and found yet.

I know that my turbo 350 tranny will bolt up to the engine with an adapter, but will it be enough for the engine. He was geting 372 HP and 431 ft/lbs at 4500rpms. If not what trannys do you guys recommend.

How does the whole AC/heater work with the newer engine, can I use my older stuff, or do I have to change that all as well.

I have been reading alot of ppl having to mod their crossmember, do I have to fab one, is there one I can use off of another vehicle?

He is letting me get all the wiring and stuff I want. Should I get the wiring to the gauges, or what. I was planning on using Dakota Digital guages.

I think that about somes it up. Thanks kbar

shanex25

iTrader: (3)

Whats the motor coming out of? You really just need the engine wiring harness. Dakota digital gauges will wire up into your factory 75 chevy wiring harness. As for the ac and heater, The heater is just the 2 heater hoses the will go right on your original heater core. As for the ac, there has been a lot of people that have used all their factory ac components. You just need a new AC compressor, (maybe the one coming out of the donor car or truck) and have an ac guy crimp up some new lines from the compressor. Im just going with a whole new set up. Vintage air makes a kit that replaces all your Ac stuff but it is pricey. The kits about $1300. The bell housing on the tranny will bolt right up to the Ls engine, I have not done it but from what i have read is that the issue is getting the flexplate mounted to the t-converter. You can get a TCI flexplate which bolts to the LS1 crank and bolts directly to a standard th350/400 converter. If you wanted to go another tranny route then get one with an over drive. 4l60e, or 4l80e if its in your budget, they both will go right on your LS. What will help you out the most with this swap is just reading swap threads on this site. You will see how everyone elses trial and error went. If you read enough post on here you will have a very strong understanding of everything you need to do to start the swap. Best of luck to you.

kbar

Thanks Shane for the reply. The engine is coming out of a 2000 model chevy truck. But he had a 4.8 I think he said bored out to a 400 sbc, it has a 4l80e but, it is a 4x4 tranny. Arent some of the gauges manual like the speedo, temp, etc. My biggest worry is can the turbo 350 handle the hp and torque from the engine. He said I can take whatever I need, so I am sure he won't mind me snatching up the ac compressor as well. Yeah I have been reading my **** off on all of these swap threads. Again thanks for the info. Any recommendation on crossmember?

shanex25

iTrader: (3)

There is a good chance that you can modify your original c10 cross-member to work, Otherwise im sure someone makes a custom one but they are probably really pricey. The gauges for the ls motor are all electrical. The sending units on the motor send data to the pcm and from the pcm to the gauges. Easiest thing to do in my opinion is to swap out the c10 gauges for some aftermarket gauges. In my el camino im using Dakota Digital gauges. You can also install different sending units on the ls to work for your gauges too. As far as the 350tbh can handle the hp... Hot rodders have been pushing those trannys well beyond 400hp years. If the tranny is strong it should be fine. My 65 probably has around 325hp or so to the wheels, the 350tbh works great! Drinks gas like water, but its next up for an ls swap... lol

Ian Johnston

I am running a 5.7 LS1/4L60E in my 1978 C20. I am in Australia, so most of what I did wont matter over your way. The AC compressor mounting if its a low one, may hit on the chassis rail, but your truck mounts maybe higher than our car ones that I used.
I modified my trans Xmember as I made my own front mount adaptors, and trans mount didnt line up. You have a better choice of mounts than we have(we have none), so you should be able to get a setback mount to put your trans in its original position.
I was looking at using Dakota Digital stuff, but way too expensive out here, so I used the instruments out of the car I got the engine/box out of.
Your turbo350 trans may need beafing up, or use a 4L60E. At least your gas mileage will be better.
And, please get some pics up. I like seeing what others are doing with their squares.