5.7 TBI down for the count.

[colbystephens]

Well, my truck didn't pass smog today. I knew this was coming, and frankly it shouldn't have passed last year but the guy at the private smog station "overlooked" the fact that my engine smokes like crazy when you get on the throttle or start it up. When I arrived at the smog station, it showed 205,666 miles (). Guess I'll put it on "non-driver" status with the vehicle insurance.

So, it's time to start planning an engine swap for real. I'm interested in modernizing things a bit with a 5.3, 6.0, or 8.1, and I'm also open to considering a diesel swap. Pretty much anything is better than a 5.7TBI... I have a LOT of reading to do, including research on what swaps are legal in places where I may end up living in the next year or so.

[/end.of.whining]

 

[sweetk30]

lots of ls swap info and builds in this section . http://coloradok5.com/forums/forumdisplay.php?f=81

also www.ls1tech.com free to be member and tons of good info .

good 5.3 is 295hp stock form . I have heard guys doing dyno tunes and gain 40-50 hp just in tune.

also cam/springs/headers/pcm tune lots of guys say around 150 hp its good for and only drop around 2mpg loss.

 

[dhcomp]

I know you haven't been driving it, is it with putting a little effort Into getting to to pass? Mine was still passing at 262 when I pulled it.

 

[colbystephens]

The main reason it failed smog is that it is burning a TON of oil. Valve seals would probably do the trick, but I don't think that's worth it to me. It's a REALLy tired engine, so I think parking it for a while till I get a new engine/trans combo figured out is best.

Also, I was planning on parking it this fall anyway, because a previous professor of mine who is moving to Italy is giving me his early '90s Toyota pickup that my wife will use to commute to L. Tahoe to teach at Sierra Nevada College while I drive the car to S. L. Tahoe to teach at LTCC. I'll do bare minimum insurance on the Toy, and it'll get better mileage for commuting without burning through my SS Swampers.

So, in all reality, the timing couldn't be better if it really did have to happen this way.

 

[shady]

if its a 2wd toy maybe... otherwise you wont notice much difference them years SUCK for mpg if they're 4x4.

 

[colbystephens]

I was under the impression that they did OK for mileage - better than my 12-13 MPG, anyway. And again, no wear and tear on my Swampers.

 

[y5mgisi]

Yay! You will really like whatever you upgrade to! Even the little 5.3 in my burb makes it a lot of fun to cruise in!

 

[blazinzuk]

So many options. Me personally I would do a ls motor. Or a 6.5 turbo. You have had that genre before so you know the pitfalls.

Those little toys aren't that awesome for mileage if its stock low 20s. But like ya said better than the blazer and it gives you a chance to do whatever motor swap you decide

 

[shady]

I was under the impression that they did OK for mileage - better than my 12-13 MPG, anyway. And again, no wear and tear on my Swampers.

I was LUCKY to get 18 on a good day and tail wind 55-60 mph with my 90 4runner v6 auto. My uncle had a 92 ext cab v6 5 speed and was getting 15-17. better than 12-13 still i guess. But not by enough to matter much. does still keep miles off the rubber though.

$1500 grandprix or something would get enough milage to pay for its self over the truck. Then when ready sell it for near what you paid...... just a thought

 

[Kay86K5]

Pretty much anything is better than a 5.7TBI...

I don't necessarily agree with this statement. Yes, I do agree that going to a new LS, as of right now, is kinda the ends all. They are great motors even in stock form and do really well. However I don't think people give the old TBI's enough credit. They are probably one of the most simple and reliable motors ever. I guess it boils down to what you really want in a truck. If it really is more of a road truck with some wheeling here and there, then yeah, LS is probably a great way to go. However there is a lot of cost that goes into one of these swaps that people don't take into consideration. Yes you can usually pick up a 5.3 with relativly low miles with everything (including harness and computer) for ~$500-$800. But after motor mounts, re-tune, fluids, ext...it usually is more expensive then you think. And that is if you don't even want to crack open the 5.3 and put it in as it. Most people want to at least check heads, valves, and possibly throw a cam at it while everything is sitting there....adding to cost.

Once again, I am not bagging on LS swaps. I think they are bad A and I would love to have one. But I am huge on reliability for the most cost effective route. So give the old TBI's a shot. The reality is most of all the TBI's nowadays are going to have almost 200,000. I don't know about anyone else, but that is a good chunck of miles on any motor (maybe other than a diesle). But if you pull the TBI and rebuild that, maybe getting some higher flow heads, throwing a moderate cam at it with a new chip burned, you could have a really nice, fresh motor with good power for probably over half the cost (depending on how far you go with the LS swap). Plus, going a route like this is way easier than retro-fitting a newer style motor into an older truck....just saying

Just thought I would add a different perspective to ya'll

 

[colbystephens]

$1500 grandprix or something would get enough milage to pay for its self over the truck. Then when ready sell it for near what you paid...... just a thought

The pick up is free. So I'll come out ahead no matter what when I sell it.

 

[colbystephens]

Yay!

I sort of thought the same thing when I failed smog...

Once again, I am not bagging on LS swaps. I think they are bad A and I would love to have one. But I am huge on reliability for the most cost effective route. So give the old TBI's a shot. The reality is most of all the TBI's nowadays are going to have almost 200,000. I don't know about anyone else, but that is a good chunck of miles on any motor (maybe other than a diesle). But if you pull the TBI and rebuild that, maybe getting some higher flow heads, throwing a moderate cam at it with a new chip burned, you could have a really nice, fresh motor with good power for probably over half the cost (depending on how far you go with the LS swap). Plus, going a route like this is way easier than retro-fitting a newer style motor into an older truck....just saying

Just thought I would add a different perspective to ya'll

Good stuff!

 

[y5mgisi]

I used to be a huge tbi fan! But in the past 10 years or so, I have never seen a system with so many ghost issues. The main one usually being idle issues. Add to that they have very little power. The highest rated tbi motor in trucks was 210hp 300ft.lb. Add to that they seem to be about done by 200k miles. Conversely, I haven't ever heard of a stock ls motor that just ran weird. I think the lowest rated ls, the 4.8 had a lowest rating of 285hp and 295 ft.lb. The highest rated tbi truck motor depends on your prospective but for the sake of argument let's use the lq4 which had a highest rating of something like 340hp and 375 ft.lb. Add to that that I have never seen a ls that was done for at 200k miles. Most will do a minimum of 300k without so much as a timing chain replacement.

If I hadn't seen SO MANY ghost and phantom problems out of tbi, I would have said it was the ultimate in reliability. There has just been so many that have had strange and sometimes unsolved problems. So many fried ignition modules and coils etc that leave the truck stranded. I have personally, never seen or heard of one ls leaving a person stranded due to a problem in the injection system. Which is really saying something when compared to how many times I know of where a tbi truck broke down.

One thing I will say for the tbi motors is they do have way better throttle response stock for stock. People often mistake that for "more torque" but when you compare factory dyno charts they make the same low end torque.

 

[Kay86K5]

I used to be a huge tbi fan! But in the past 10 years or so, I have never seen a system with so many ghost issues. The main one usually being idle issues. Add to that they have very little power. The highest rated tbi motor in trucks was 210hp 300ft.lb. Add to that they seem to be about done by 200k miles. Conversely, I haven't ever heard of a stock ls motor that just ran weird. I think the lowest rated ls, the 4.8 had a lowest rating of 285hp and 295 ft.lb. The highest rated tbi truck motor depends on your prospective but for the sake of argument let's use the lq4 which had a highest rating of something like 340hp and 375 ft.lb. Add to that that I have never seen a ls that was done for at 200k miles. Most will do a minimum of 300k without so much as a timing chain replacement.

If I hadn't seen SO MANY ghost and phantom problems out of tbi, I would have said it was the ultimate in reliability. There has just been so many that have had strange and sometimes unsolved problems. So many fried ignition modules and coils etc that leave the truck stranded. I have personally, never seen or heard of one ls leaving a person stranded due to a problem in the injection system. Which is really saying something when compared to how many times I know of where a tbi truck broke down.

One thing I will say for the tbi motors is they do have way better throttle response stock for stock. People often mistake that for "more torque" but when you compare factory dyno charts they make the same low end torque.

All extremely good points as to why more and more people are going with LS swaps instead of sticking with TBI. The only light I was trying to shed was the cost associated with the swap that most people overlook. And your point about the power of a stock TBI was exaclty why I stated you could put some money into the motor with heads, cam and a properly tuned chip and get somewhere north of 300hp. Yes, not even what a stock 5.3 puts out, but once again, it depends on what you use the truck for. I prefer rock crawling where an extra 50-60hp doesn't really do me any good. If you street drive over passes or like to run the dunes, then yes, that extra 50-60 could make the difference. And the ghost of the systems, it does happen with all of them. LS's are less frequent, but I think if you give them another 5-10 years, we will be saying the same thing about them as we do with the TBI's right now.

Once again, trying to get poeple to look at it a little differently.

 

[y5mgisi]

Hey I'm with ya! Always good to have two valid points to consider! And you are right. There is often a case to be made for a rebuild and light mod on a tbi motor! Rock crawling and stuff like that does fit a tbi well with its responsiveness. There is a case to be made for either motor. It just takes a little soul searching on the part of the individual to decide what really fits best.

 

[Kay86K5]

Hey I'm with ya! Always good to have two valid points to consider! And you are right. There is often a case to be made for a rebuild and light mod on a tbi motor! Rock crawling and stuff like that does fit a tbi well with its responsiveness. There is a case to be made for either motor. It just takes a little soul searching on the part of the individual to decide what really fits best.

Amen, brother

 

[snowdriver]

I am a tbi fan myself, simple and reliable,and I know how the system works,not great for major horsepower,but the drive ability is outstanding

 

[Chevy305]

As far as LS goes, are you guys talking about electronic throttle response? If so tuning can remove the lag and improve the throttle response back to what a cable throttle has. Plus the LS factory tuning has quite a bit of torque management built in. If you remove that, it makes driving them quite a bit more lively.

As far as LS vs TBI, let me put it this way: TBI is like a rotary phone, LS is a smart phone. In fact I can tune my LS engines from my smart phone.

 

[y5mgisi]

No I'm not talking electronic. And electronic has milliseconds lag after a tune anyway. I mean tbi just has better throttle response. The ls can feel lazy in a truck compared to tbi taking off from a stop light, but no doubt the ls is more powerful. It's hard to explain but if you drive a stock tbi truck, then a stock ls truck, the ls isn't as "snappy" feeling. But in a race, or heavily loaded, obviously, the ls truck wins every time.

 

[ssyork]

There are definitely points to be made for each. After having a tbi with vortecs, cam, tune and a bb tbi unit and now my 5.3ls with a tune. There is no way I would rebuild a tbi motor. Just sold my heads and cam for $350, vortec to tbi intake $280 and the tbi unit for $100. Plus you're going to need a $80 fuel pump to go with and a new tune for a couple hundred. Tack that onto a rebuild and you're at an easy $1500. I just spent $2041.62 for the swap for every little last piece. It takes 6 wires to hook it up. Stock parts are available everywhere. 20 year old motor parts aren't as available in places like Moab. Oh and the power is so much more fun! Haven't read or heard of someone who has done the swap to ls say they regreted it. Just my 2 cents worth.