late 90's vortec 350 in a 79 stepside

[bradf74]

I have a 79 chevy stepside that I would like to swap in a late 90's vortec 350. I have couple reasons for this. They are cheap around here, and reliable. I would like more reliabilty than the 327 that is in the truck now. I do not want/need an LSx. Power is not a real concern. Those vortecs have plenty power for what I am looking for. The TH350 trans is ok (might rebiuld it, but it is good now.) My questions are:

Would this swap be easier than the lsX swap? I believe the vortec's will not require mods to the motor mounts.

Would I have to have the late model tranny with the vortec? Or can the computer be convinced to work with the th350?

Does the vortec require a return line to the gas tank? Will an inline fuel pump work?

Thanks

[Pyrotechnic]

If you found a manual transmission computer, you could use your turbo 350. It would actually be beneficial to get the motor and matching 4L60E transmission as a unit because the 4L60E has and overdrive gear.

If you just wanted to go carbureted and use your existing transmission, then the Vortec 350 would be a good route. However, if you are going to fuel inject and use the 4L60E, it's actually not that much more work to step up to a 5.3L. With some readily available motor mount adapter plates, it will drop right in place. If you are going to go through all the trouble of the computer and wiring, then just go all out. Cost is not really a factor, since the 5.3 seems to be a dime a dozen.

[turbotank]

or maybe even the 4.8,cause everybody wants the 5.3!Its got pretty good juice dez days.

[bradf74]

Does anybody make a transmission crossmember for this swap? (4l60e into 79 truck)

[Pyrotechnic]

All you have to do is slide the cross member back a few inches and drill the new holes.

[silvereagle07]

If you're talking about Vortec up to 99 you could always carb it. Correct me if Im wrong but I believe the trans from your truck will work.

[bradf74]

The more I have researched this, I will most likley go with the carb setup on the vortec motor. The intake is $140 from summit, and I would need an electric fuel pump. That would allow me to use the th350 and avoid the computer and wiring snafu. I could also keep my mechanical guages. I believe I can do this swap for less that $1000.

[us111]

HELLO,got that same motor in a 76 stepside,edell intake,edell 650 carb ,mine is 4 wheel drive,350 tranny,and for as heavy as it is it will go from 0 to 60 in a heartbeat.plenty of power,easy to work on.all u need is the carb,intake,electric fuel pump,fuel pressure regulator and your good to go.
started to go with fuel injection but the hassle in my opnion just wasnt worth it,plus like has been said when u carb it all your standard stuff bolts right up (tranny,etc)

[68c10owner]

Originally Posted by turbotank

or maybe even the 4.8,cause everybody wants the 5.3!Its got pretty good juice dez days.

If you find one that needs rebuilding I`d ge a 4.8 because they use the same block for the 4.8 and 5.3. Only the crank and pistons are different.

[silvereagle07]

bradf74 what year is the engine exactly? I have built a vortec engine to go in my 84. Is it a 5.7 or the later 5.3?

[bradf74]

I have not bought an engine yet. I am just in the planning stages. I was hoping to score a 5.7L (350) from about 97 or 98.

[spudz]

96-99 vortecs kick ass.. I got a couple of them.. I am in the process of installing the motor and trans out of my 96 tahoe into my 96 s10 blazer and keeping it fuel injection.. should look almost stock under the hood except for some core support modifications.. .I recomend these motors... the lsx motors are nice....and if I had the money Id love to have a LS2 in one of my SWBs. You can keep it fuel injected and I found a few places that sell the wiring harness to do it.. its just nice to walk out to your truck in the winter and spin the motor over once and have it bust off without pating the gas and feathering it for a while..

[bradf74]

who sells the wiring harness to do the conversion?

[82stepside]

Hey in summer of 2007 i did a 96 vortec conversion in my stepside after reliability issues with my 250-6cyl. Those vortecs uses the same clam shells and rubbers as every other chevy v8 prior to it. the block is basically the same, its just mechanical fuel pump delete, and has BS plastic timing chain cover that no one seems to make in either steel or aluminum. I bolted mine to the same shift kitted TH350 that i had put in brand new when i bought the truck. I put a edelbrock performer RPM Airgap intake and a 670 street avenger on it and it runs really well. The only real issues Ive had are keeping my electric fuel pump pressure regulated and happy (i get these weird pressure drops where it drops to 3 1/2 pounds and stays there. About the only thing that seems to fix it is taking the system apart and putting it back together and resetting it to 7 pounds, and it will stay like that for awhile. Vented gas cap is no help.) And getting the right HEI distributor advance curve for that factory hydro-roller cam. But im about ready to start really dialing the carb and timing in...

[gchemist]

Buy a stock 350. Swap the cam- XE-268. Add an Edelbrock RPM Air gap intake. Add headers. You'll be one happy camper.

I saw a 67-72 with the combo above at a track. 3.73 gears and 350th it ran the 1/4 mile at 13.3! with slicks! Same time as a stock C-4 Vette!

[draggin86]

i am about to do this swap. i have a 98 5.7 with a 4l60e i want to keep the EFI seems like the plug and play harness for the motor are about 700 so if you want to keep the EFI it will be a little more spendy but i think in the long run it will be worth it.. there are a few places to get the harness from. i have been in contact with a guy from speedscenewiring.com he would do a new harness with a tune for 900 which is the best i have found. i believe the painless harness is around 700 bucks with out the tune.. if you are going this route you need to get a 90-91 burban cluster to use the 4l60e.... as stated above it use same motor mounts im not sure about the 4l60e mounting up to the stock tranny mount im sure it can be done.

[bradf74]

Have you checked speedtech.com? Over at the LS1tech website, he seems to be the man.

I was thinking that the cross member from the 98 truck (for the trans) maybe the best bet.

Not trying to get into your business (and you can PM if you want) how much was your motor and trans combo?

[draggin86]

i have not... ill have to talk to him! the motor is out of one of my other trucks so it was free! lol

[bradf74]

For this following this thread it is speartech.com. It was 30 degrees last night in Mississippi. That WAY too cold for us rednecks. I guess my brain froze.

[84 400]

If any one out there is looking to go 5.3 steer clear of the 00-03 ones. ours has developed the piston slap.

[68c10owner]

Any of you guys who swapped to a vortec but yanked the fuel injection off for a carb let me know if you want to sell the fuel injected stuff. I just made a deal with a buddy for a 5.7 vortec but he`s missing the intake, distributor and all the fuel injection and harness.