5.7 liter rebuild advise

[imiceman44]

So I was planning on getting one of the crate engines some dealers were selling for $2k shipped but I missed the boat.
So I have an engine that seems to be rebuildable.
I have an engine builder friend of mine that is going to build it for me in February but he's thinking build it wild and top it with a carburetor, but I want it for my suburban to overland.
I think efi is the way I want to go.
Now my thoughts are to keep it mild, keep the torque as low as possible in the rpm range, maybe better aluminum heads mild cam, and either run the stock injection system from 1999 or if not too much more money try a hybrid LS system I keep hearing about.
Hit me with what you got.
It would be wise to keep external parts off the shelf items for easy repairs while traveling but if there's enough advantages I could drop that requirement.

 

[Scribbles]

Do you have specific HP/TQ goals you want to meet or exceed? I intended to go this route for my K5 and I really intended to use these heads. Sadly I never got to the building part and I dropped a 602 crate motor in it which does perform quite well but I still wonder what if I had a roller cam and Edelbrock pro flo.

 

[imiceman44]

Do you have specific HP/TQ goals you want to meet or exceed? I intended to go this route for my K5 and I really intended to use these heads. Sadly I never got to the building part and I dropped a 602 crate motor in it which does perform quite well but I still wonder what if I had a roller cam and Edelbrock pro flo.

View attachment 398559

No goals.
Just any improvements that are worth it for overland.
Low end torque and reliability is the goal.

 

[tRustyK5]

Stock LQ4 or LQ9. i know it's LS, but they are monsters in dead stock form, all factory parts you can find anywhere and still easy enough to find with a bit of patience.

 

[imiceman44]

Stock LQ4 or LQ9. i know it's LS, but they are monsters in dead stock form, all factory parts you can find anywhere and still easy enough to find with a bit of patience.

I have 8 engines sitting in my shed, not buying more engines, just trying to use what I have and improving a little on it.
I also prefer the L31 because no need to change anything, it's a direct fit

 

[tRustyK5]

Fair enough, just throwing it out there. I'm no LS fan boy, but it's hard to argue with the numbers.

 

[Scribbles]

No goals.
Just any improvements that are worth it for overland.
Low end torque and reliability is the goal.

In that case I’d slap a set of Vortec heads or the ones above, stick a roller cam in it if your block will accept it and roll on! If you’re trying to play with the factory TBI you should be able to get a cam that’ll work, but in all honesty I am itching to try the Edelbrock pro flo 4 and after my experience with the GM TBI in my K5 I’m not interested in GM TBI unless you’re trying to end up very close to stock.
I started leaning away from vortec heads because I understand they’re prone to cracking when overheated but I know that they are a good flowing head so I wouldn’t be scared of them especially for a budget build.

 

[Big Ray]

What do you have lying around...?

 

[82355]

Vortec heads are not a good option if you have emmisions. No exhaust cross over.

Martin

 

[imiceman44]

In that case I’d slap a set of Vortec heads or the ones above, stick a roller cam in it if your block will accept it and roll on! If you’re trying to play with the factory TBI you should be able to get a cam that’ll work, but in all honesty I am itching to try the Edelbrock pro flo 4 and after my experience with the GM TBI in my K5 I’m not interested in GM TBI unless you’re trying to end up very close to stock.
I started leaning away from vortec heads because I understand they’re prone to cracking when overheated but I know that they are a good flowing head so I wouldn’t be scared of them especially for a budget build.

It's already a roller cam vortec.
It's a 1999 5.7 liter.
I haven't checked the heads yet but usually they are prone to cracking and if there's a hint I am getting aftermarket aluminum heads.
The crank is for sure damaged, not sure if replacing it or machine it, the machinist will figure that out.
The rods and pistons are confetti.

Vortec heads are not a good option if you have emmisions. No exhaust cross over.

Martin

No emissions on my 74 suburban

 

[dyeager535]

Personally I'd try and stay away from the Vortec injection setup. Not a ton of experience with them, but I know they are far more problematic than "normal" injection systems. And for reliability alone, if I had a decent choice, I'd do something else.

I'd have to look again, but I bet on low end torque, the TBI and Vortec 5.7s are nearly identical. The Vortecs make more power, but it is significantly higher in the RPM range IIRC. Low end is hurt with larger intake ports, valves, or higher lift camshafts. The TBI heads generally suck, EXCEPT in terms of building low end torque. About all you can realistically do for low end without penalty is headers. The only tangible benefit to a roller cam in this situation IMO is no worry about the lessened additives in modern oil that can affect flat tappet setups.

If TBI was easier to tune, I'd go that route on an L31 block, headers, and aftermarket heads that allowed me to retain whatever emissions is required. Yeah, you might lose something on the low end with the Vortec cam, but it's a roller at least. Bumping the compression up with ~64CC aftermarket heads will also help make power with 87 octane, which is possible with the modern chambers. TBI flat out works, and runs very well when tuned properly. Again the problem with it is tuning. But find someone with an aftermarket system that says it runs perfect under all conditions, all the time, and didn't or doesn't have to be futzed with to at least get it dialed in close. It's just easier to do than with TBI. But it is possible with TBI.

 

[Big Ray]

Stroke it...383. With a Proflo. Torque, torque, torque.

 

[imiceman44]

Personally I'd try and stay away from the Vortec injection setup. Not a ton of experience with them, but I know they are far more problematic than "normal" injection systems. And for reliability alone, if I had a decent choice, I'd do something else.

I'd have to look again, but I bet on low end torque, the TBI and Vortec 5.7s are nearly identical. The Vortecs make more power, but it is significantly higher in the RPM range IIRC. Low end is hurt with larger intake ports, valves, or higher lift camshafts. The TBI heads generally suck, EXCEPT in terms of building low end torque. About all you can realistically do for low end without penalty is headers. The only tangible benefit to a roller cam in this situation IMO is no worry about the lessened additives in modern oil that can affect flat tappet setups.

If TBI was easier to tune, I'd go that route on an L31 block, headers, and aftermarket heads that allowed me to retain whatever emissions is required. Yeah, you might lose something on the low end with the Vortec cam, but it's a roller at least. Bumping the compression up with ~64CC aftermarket heads will also help make power with 87 octane, which is possible with the modern chambers. TBI flat out works, and runs very well when tuned properly. Again the problem with it is tuning. But find someone with an aftermarket system that says it runs perfect under all conditions, all the time, and didn't or doesn't have to be futzed with to at least get it dialed in close. It's just easier to do than with TBI. But it is possible with TBI.

I agree my 89 tbi 350 has been running flawlessly for 9 years even with all the abuse I put it through.
It had a tick my guess now is a bad lifter, at the beginning I assumed bad thrust bearings, so I didn't do any maintenance for 5 years, no oil changes, no spark plugs, no cap and rotor, I put 45k miles, and it still ran perfectly except now I think I wiped the bearings and I have low oil pressure.
I was destroying the engine to justify putting a better engine, the 454 I had.
Since then I have been driving a Vortec and I like it better.
The weak link in the Vortec injection system is the spider and I believe there's an update for it.
Not sure how good it is but I haven't needed yet.
I haven't seen an aftermarket setup yet that has the reliability of either so I still tend to stick with oem.
Although I do have the mentality of anything can be improved on and I am willing to work on something until I figure it out if the outcome is worth it.
I am also pretty good with logical analysis of database and with diagnosis and if these aftermarket injection systems have the potential I might consider them.

 

[dyeager535]

If you think tuning would be something you'd have no issue really getting into, then perhaps OEM with mods is a potential way ahead for you.

No reason a carb intake with TBI adapter can't be used on pretty much anything, and since TBI and TPI use very similar components and processes, what you learn tuning one will be applicable to the other for the most part. I'd assume getting into tuning would run you $300 or so, I haven't looked to see what moates is selling their stuff for now.

The only advantage I see with the aftermarket stuff is that the tuning interface is simplified, and handier. It sounds like the good systems save you some tuning effort, but not all.

Buddy had some issues with the Vortec, that whole injection setup issue plus some distributor problem, but that was probably a one-off.

 

[imiceman44]

If you think tuning would be something you'd have no issue really getting into, then perhaps OEM with mods is a potential way ahead for you.

No reason a carb intake with TBI adapter can't be used on pretty much anything, and since TBI and TPI use very similar components and processes, what you learn tuning one will be applicable to the other for the most part. I'd assume getting into tuning would run you $300 or so, I haven't looked to see what moates is selling their stuff for now.

The only advantage I see with the aftermarket stuff is that the tuning interface is simplified, and handier. It sounds like the good systems save you some tuning effort, but not all.

Buddy had some issues with the Vortec, that whole injection setup issue plus some distributor problem, but that was probably a one-off.

Yeah vortec issues aren't very common on the injection side other than the spider leaking.
I also see all the time engines with 350k-480k still going.
I just bought a van with 293k still going and passing smog in California

 

[Wes Harden]

Vortex Spyder was updated very reliable now.
I remember the distributors being sh+& and caps and rotors are garbage too.
If your vortec starts missing cap and rotor 1st.

 

[imiceman44]

Vortex Spyder was updated very reliable now.
I remember the distributors being sh+& and caps and rotors are garbage too.
If your vortec starts missing cap and rotor 1st.

Yeah I have had to change cap and rotor on a couple already.
If I stick with stock, I will put all new upgraded parts for sure.

 

[bp71k5]

If you decide to try TBI, I can help with tuning/programming chips. You’de just need to modify a 7747 ECM to accept replaceable chips, and deal with the post office mailing back and forth.

 

[imiceman44]

If you decide to try TBI, I can help with tuning/programming chips. You’de just need to modify a 7747 ECM to accept replaceable chips, and deal with the post office mailing back and forth.

Tbi has been great for me, but I will not be programming tbi.
I might do the tpi on the tbi engine and I think I will keep the Vortec injection stock or close to it

 

[cheavyk10]

My vote would be for an intake for a 4 barrel and an aftermarket stand alone EFI system. I have been running the Summit Max-EFI for almost 2 years and it's been trouble free. I have put it through abuse in all conditions. Self learning but programmable and customizable. No timing control. After initial set up, the only thing I had to tinker with was some cold start settings. I believe @Kay86K5 runs one too, maybe he can chime in.