Twin turbo 5.3?
 

So, a little background... I tore the reverse gear out of my 1979 k10 with a 305/th350/np203. My friends finally convinced me to do a 5.3l swap into the truck...


So while perusing a local junkyard I found 2 6.5 turbodiesels being parted out... both turbos are there and in good condition. I've seen a video or two of "stock" 5.3s with 2 turbos but I have a feeling thats not exactly true.


Should I attempt this? Is this a doable build on a 3-4k budget? I will raise my budget as neccessary.

Re: Twin turbo 5.3?
 

Google Sloppy Mechanics. Denmah builds some pretty damn fast cars/trucks with cheap parts and runs the **** out of them. There is even a company that offers a "sloppy mechanics kit" for 800(?) that has all the parts he usually uses.

Re: Twin turbo 5.3?
 

Thanks Tiny. That website was a perfect place for me to start looking. I'm going to go for it.

I've decided to go with a 5.3/4l60e/np241 setup. I haven't decided what I want to do for suspension yet. I might end up going with a 4" lift but we'll see, I kind of wish it was a 2wd for this build but oh well.

The plan of action as of now is:
•to get the engine/transmission/tcase.
•get LS6 top end
•get my turbo setup (from headers to exhaust tips)
•remove bed clean up/reinforce frame as needed. Body work and gas tank/fuel pumps
•remove cab and do the same thing as above
•remove front clip (again do everything like above.) Drop everything in and hope to God it will run.

IF it doesn't blow up, off to get dyno tuned it goes. If it does I'll just cry for a minute and start over.

Axles I haven't thought about much yet, might just build the 12 bolt I have.

For the gas tank I'll start looking at either newer tanks or building a sump in mine. I want to keep the truck looking as stock as possible from the outside so no in bed tanks for me.

The frame has one or two pinky sized holes in it so I'll have to figure out how I want to fix that.

The goal is low 600hp and if not then high 500.

This is going to take me some time but I am going to do it. I guess as I go along I'll just add this to the build thread I already have. No sense in making two.



If I have left anything out or should change my plan of action or lower my overall goal please let me know. This is my first build and I don't want to learn the hard way lol.

Re: Twin turbo 5.3?
 

And no I'm not using those crappy turbos off of the 6.5s lol. I've learned better in the past 20 hours haha.

Re: Twin turbo 5.3?
 

I just looked through your build thread. If I were in Alaska Id keep 4wd but I love 2wd. Since you will have the front clip off and engine/trans out, its not hard to convert to 2wd.

Why the LS6 top end? Its expensive compared to other options. Are you talking heads/cam/intake?

Edit:
The engine we are building for my brothers Nova has LS6 heads and intake on a LQ4 to bump up compression (with a custom cam) but he wasnt as concerned with the cost as I am

Re: Twin turbo 5.3?
 

I know it's not hard to swap over but since I've gotten the truck, all my original plans went completely out of the window so the only thing that's left is its 4x4. The truck will have to be built up from ground up IMO for this setup so it'll be sitting for at least a year.

I picked the LS6 because I believe it was originally intended to take the abuse. I've only started researching EFI motors for about a week now so if there are more cost effective heads out there I'm all ears.

As for cam, I'll be looking more towards a custom cam.


I can assure you that the next truck will be on the ground.:metal:

Re: Twin turbo 5.3?
 

Depends on how much boost you want to run. Look at the 317 heads. 600 on stock heads is possible. The stock intake flows pretty well also. You can run the ls6 cam if you can find one used for cheap. The LSA is good for turbo motors.

Re: Twin turbo 5.3?
 

So, what did you learn about turbos from a 6.5? I have 2 of those on the shelf I was saving for my eventual ls swap.

Re: Twin turbo 5.3?
 

It took some digging because there's not much info on these. It seems like borg-warner and IHI produced these gm-x turbos together...

The first 6 posts on this thread were on topic, after that it went down hill. http://www.thetruckstop.us/forum/sho...-quot-bad-quot

I believe that the RHE61 is the IHI version of the turbo.
http://www.ihi-turbo.com/turbo_RHE-RHF.htm


What I took from what I read is with the amount of boost I want to run, power would be restricted due to the sizing of the turbines. i'm not saying its not possible to use these on a small block I believe you'll see more gains with a different one. I was a hair away from buying those turbos but there is a reason the motor was taken apart and they were just sitting there in the open. The 6.5 was not at all built with our power hungry ideas in mind so I would say they selected the turbo for the intended purpose.

These are my opinions based on what I have read which could be baised since it was off of other forums. But what do I know? I just happened to stumble over into this section 34 ish hours ago:lol:

Re: Twin turbo 5.3?
 

Check out the turbo forum. They have a section for GM small block and ls1

Re: Twin turbo 5.3?
 

Here's an older thread on a single turbo 5.3 in a 4x4. I believe there is a more detailed thread on that truck here somewhere.

http://67-72chevytrucks.com/vboard/s...d.php?t=228856

Re: Twin turbo 5.3?
 

Thanks for the websites. I'm slowly starting to get together what I want for the motor setup. Denmah's build really helped narrow down and answer A LOT of questions I had.



Thanks for the link. Definitely a good thread and it definitely helped me along with the previous sites mentioned.




Decided to keep the truck heads and adjust the valves and springs. I am going to keep the stock PCM and tune it, no Microsquirt on this build. 80lb injectors, stock fuel rail, 3/8ths fuel line...

Turbos: Still need to decide turbos but no rush right now

BOV: I'm going to run one 50mm BOV

Cam: will be between an LS6 or custom cam from TICK performance.

Fuel Pump/tank: I need to consider my options here on what is more cost effective/least problematic. I could use the same tank that came with the truck and install a sump and run the Walbro 400 pump OR, put in an EFI tank. Ill have to look more into that as time moves on.

Cooling: Ill have to look into more.




At this point, if you asked me what I was building this truck for I couldnt exactly think of a better reason than, "to make me smile":devil:

Re: Twin turbo 5.3?
 

I wonder if a holset hx-35 would be a good turbo. You can get them new for around $300.

Re: Twin turbo 5.3?
 

That is one of 3 turbos I'll be looking at more in depth. The other two are the GT45 and on 3 76mm turbo.

Here's a good site with formulas that will help with turbo selection

http://www.forcedinductions.com/help.htm

Re: Twin turbo 5.3?
 

I'm in the same boat as you on picking a turbo. I've seen a lot of good things about the gt-45s, but there seems to be some very mixed reviews about the on3. I think I'm going to go with the sloppy mechanics kit with some 80lb injectors on e85 in my 79 with a 5.3.

Re: Twin turbo 5.3?
 

Do yourself a favor and ditch the 4l60e and get a 4l80e.

Re: Twin turbo 5.3?
 

My only concern with the 80e is that they were built for HD trucks. I saw someone with a fox body mustang that was complaining about the 80e saying it was holding the car back.





Found a 5.3 133k with a 90 day warranty $775 shipped to my house with computer, harness, and computer... It will be ordered momentarily.

Re: Twin turbo 5.3?
 

Lol....you know what holds a car back more than an 80e? Being on a rollback wrecker.

I grendaded a 4L60E with a mild 5.3. They are not meant for abuse/racing/big hp. If you want to pour a few thousand $ into one, yea they'll live....but take the advice given to you, and go with a 4L80e.

Re: Twin turbo 5.3?
 

Engine is ordered and should be here (weather permitting) friday... I'm sure it'll be delayed because of the storm. The motor is coming from PA.


For the building part of this I will post in my build thread, however any questions I have along the way I'll keep here if not, I will provide links so others can use this one as a reference.


I've got a lot of negativity coming from a good friend of mine on this build, his concerns are $$$, time, and my not being able to fully enjoy the vehicle due to the costs and time involved.


I'm pretty motivated and set on this decision even though I've never built anything so in depth before. For the next month or two I'll be in my learning phase. After that im throwing wallets and wrenches at it.:D

Re: Twin turbo 5.3?
 

Gotcha, and your right. Ill look into the 4l80e and see if there are any deals around here.

Edit: Ill look into your build.

Re: Twin turbo 5.3?
 

4l80e and a transgo hd shift kit with the right converter will hold up to what you are looking to do. Just make sure to get a good core

Re: Twin turbo 5.3?
 

Tell your buddy that there are plenty of people out there doing the swap and enjoying it. Price out what it will take to build a healthy SBC or BBC and then compare, its pretty damn close. I did a lot of extra stuff to the truck as far as suspension and interior at the same time and I spent just as much time on the suspension as I did the motor swap. It's very straight forward and not that complicated. Get the motor in and drive it while you are collecting the turbo parts.

Re: Twin turbo 5.3?
 

Tips/advice:
If you want different heads just use 799/243s and keep the truck intake for simplicity. they will lower the compression a little and flow better than the stock truck heads. The stock truck heads should get you to your HP goals though.

Re: Twin turbo 5.3?
 

Wasted Income has some great build threads and tons of knowledge.

Price wise I doubt the LSX will cost more than another build with similar HP. I was originally going with a blown BBC but traded my blower for a 5.3 as the BBC would have cost me thousands to build how I wanted it. Then there was the whole issue of getting a standalone controller for a 4l80e as I didn't want to turn a ton of RPM's on the freeway.

Re: Twin turbo 5.3?
 

I'm thinking about running the stock heads now and just doing valves/springs for a bigger cam.


My friend I mentioned earlier who's trying to talk me out of it is doing my standalone harness from the factory harness. Lol.