FrankenCub

Hey guys, I've been reading the threads for a couple days now and figured I might as well jump in. I have a '71 GMC that will be needing a heart transplant soon and thought a 5.3 would be pretty sweet way to go. Well, maybe even a 6.0. Especially seems I found that there is a way to go carbed. I hate FI, just not my cup of coffee.
A couple questions if I may, I'd like to stay with my 3OTT if at all possible, until I get the extra funds for a nv4500, it really needs OD. 3400rpm on the highway kinda sucks. I thought about going to a 700r4 but I really prefer to row my way down the road and having a standard tranny also keeps my wife from driving my baby lol. She's really rough on vehicles.
Another question is with the manifolds, they seem to be for higher rpm range, my truck is a driver and I still use it as a truck for towing and hauling firewood. Is there a manifold available for the lower rpm ranges ?

I'm not ready to jump into the project just yet, I want to get all the information needed forst and start gathering parts first. I kinda thinking I can go this way cheaper than having a stout conventional 350 built.

speedtigger

iTrader: (16)

Welcome to LS1 Tech Frankencub!

The 67-72 trucks are great looking pickups. Post up a picture. As for going carbed, that is not a problem. In fact, one of our sponsors has a special right now at a great price:
https://ls1tech.com/forums/carburete...0-shipped.html

The Performer RPM manifold will be a great choice for what you are doing. As for your transmission questions, you may get more insight for your particular case in the conversion section:
https://ls1tech.com/forums/conversions-hybrids-28/
Do some reading in there. I would bet others have done similar conversions.

windmill

iTrader: (4)

Welcome!!!

They are a lot of info here, also on 67-72 chevy trucks site too,, lots of info here for the carb guys tho..

Im changing my 1972 chevy truck at the moment too,, it will have a 5.3 with 4l60 trans. its been a long drawed out thing with my truck because it took it all apart.. good look on your truck build..

FrankenCub

Thanks for the welcome guys. That is a great price, unfortunately I won't be ready for a couple months yet. Tax time ya know lol. I'm sure I won't have a problem finding used if he doesn't have a sale going when I get ready. I've been casually looking at different engines too, up here idiots quickly forget how to drive in the snow so there is a LOT of wrecked 2 wheel drive trucks getting their engines yanked for reasonable prices. I plan on keeping it as stock as possible, for my uses I don't see any need to make any other mods. She'll still produce way more than my 307 currently in it.

I have looked some in the conversion section but haven't found any old school tranny info yet. I am also a member of the 67-72 Chevy truck forum and have found some info there but can't find it now that I'm interested in it lol. Terrible memory. I'll look around some more and weigh the options, and probably make some calls to the wrecking yards that I see most of these engines coming out of, maybe they could hook me up with a LSx+nv4500 combo if the price is right. Not holding my breath there, most every engine I've seen for sale has had a flexplate. Must be the guys drivin sticks are better drivers

Here she is..."Mercedes"
I used to have a really nice classic Mercedes and always wanted to name my daughter Mercedes, but seems I never ended up with one my step daughter told me I should name my truck that. It kinda stuck.

speedtigger

iTrader: (16)

Great looking truck. I would drive that everywhere.

FrankenCub

Thanks. I drive it pretty much everywhere. Except in the snow ! It usually goes into hibernation in November through March, but have driven it a couple times this winter when the roads were clear so I could pick up another vintage Ski Doo. She'll stay parked the rest of the winter unless absolutely needed and the roads have no snow.
The more I research this LSx stuff, I think I'm going to also put one in a mid 70's 4x4 that I won't worry about the snow with. I'm really liking this LSx idea !