TBI Engine Question

[Szil66]

Hey guys, this may have been asked somewhere but I'm not sure what to search for to find it, but here's my question.

I have a 95 GMC with the 5.7 TBI. I am looking at doing a motor swap to gain more power. I am leaning back and forth between a 5.3 or a built TBI motor. I know I can find a junk yard 5.3 for cheap but I've already done it that way once in my 60 Bel Air and I don't want to go that way again. I just had too many headaches with it. If I do a 5.3 I'm going to buy one that been tested, has everything, and has a reworked harness and flashed ECM already.

If I get a rebuilt TBI, I know I will have a faster swap but that's a lot of money spent and I will never get more power out of that engine.

So finally to my question: Older blocks can usually be rebuilt cheap and built for some good power. But I don't know if the TBI engines have certain sensors that I need that the older blocks don't have provisions for.

Basically I am asking if I can swap in a carbureted block, put a TBI intake on it, and run it? Will I need to chip my ECM? Or get a bigger TBI?

I am just looking for the most cost-effective way to get more power out of my pickup without doing away with fuel injection. I know TBI isn't the best set up, but when it's cold it still beats a carb IMO. I'd like to do the 5.3 swap but it's my daily and as many problems as I had with my Bel Air it just scares me that the swap won't go like I want it to.

Thanks for the help

 

[96-1500]

Hey guys, this may have been asked somewhere but I'm not sure what to search for to find it, but here's my question.

I have a 95 GMC with the 5.7 TBI. I am looking at doing a motor swap to gain more power. I am leaning back and forth between a 5.3 or a built TBI motor. I know I can find a junk yard 5.3 for cheap but I've already done it that way once in my 60 Bel Air and I don't want to go that way again. I just had too many headaches with it. If I do a 5.3 I'm going to buy one that been tested, has everything, and has a reworked harness and flashed ECM already.

If I get a rebuilt TBI, I know I will have a faster swap but that's a lot of money spent and I will never get more power out of that engine.

So finally to my question: Older blocks can usually be rebuilt cheap and built for some good power. But I don't know if the TBI engines have certain sensors that I need that the older blocks don't have provisions for.

Basically I am asking if I can swap in a carbureted block, put a TBI intake on it, and run it? Will I need to chip my ECM? Or get a bigger TBI?

I am just looking for the most cost-effective way to get more power out of my pickup without doing away with fuel injection. I know TBI isn't the best set up, but when it's cold it still beats a carb IMO. I'd like to do the 5.3 swap but it's my daily and as many problems as I had with my Bel Air it just scares me that the swap won't go like I want it to.

Thanks for the help

I'm assuming everything is mechanically good on your current 5.7.

I don't think you'll be particularly happy TBI swapping an old carb engine. Rebuilding them for good power is generally associated with running a carburettor.

Honestly, if you're committed to staying with TBI (hey, I'm not bashing TBI. I love them - extremely simple, super reliable, ridiculously cheap to buy parts for), probably the best balance of cost and power gain would be to somewhat upgrade what you have. There's lots of info here on TBI mods, tuning, intakes, exhaust, etc. Lots of relatively inexpensive stuff that will help the TBIs power.

Pretty much anything is possible with enough time and money, but TBI engines are simply not power houses by nature.

 

[Szil66]

I'm assuming everything is mechanically good on your current 5.7.

I don't think you'll be particularly happy TBI swapping an old carb engine. Rebuilding them for good power is generally associated with running a carburettor.

Honestly, if you're committed to staying with TBI (hey, I'm not bashing TBI. I love them - extremely simple, super reliable, ridiculously cheap to buy parts for), probably the best balance of cost and power gain would be to somewhat upgrade what you have. There's lots of info here on TBI mods, tuning, intakes, exhaust, etc. Lots of relatively inexpensive stuff that will help the TBIs power.

Pretty much anything is possible with enough time and money, but TBI engines are simply not power houses by nature.

So far, it is still mechanically sound but it has 217k on it. It's worn out! And the reason I am not considering just rebuilding mine is because it's my daily and the only reliable vehicle I have on hand right now, so I can't have it out of commission while my motor is being built. And if I build my motor I will go off the deep end and just throwing parts at it and racking up a bill..

I am looking at crate engines and have found a few in the 300-350hp range for $2500-$3000. Which is a significant step up from the stock 195-210hp that the TBI is rated at..

I was just wondering though because I can find 400+ hp carb motors for about the same cost.. Which I really don't need that much power, I don't do much with it but occasionally pull a trailer. And mine is a complete dog when it comes to that...

Plus I am not sure the TBI will even keep up with 300hp more or less 400... So I think that is the route I am going to go.

But I do get what you're saying about TBIs not being power houses but I do need a little more power just so my pickup can be used for pulling a trailer or what have you.

I also plan on putting headers on and a better intake. The engine place I talked to said the stock TBI would work but will probably look into chipping it.

Thanks for getting back to me!

 

[Keepinitoldskool]

buy a vortech motor and and keep the tbi with a different intake manifold. that alone would be a vast improvement. the limit to these tbi engines is the head design.

Sent from my SAMSUNG-SM-G890A using Tapatalk

 

[CrustyJunker]

I was a guy who attempted to build an all out TBI motor that was still emissions compliant because of the area I live in. Where I live, LS's are like gold and people want a ton of money for a high mile LS (220,000 mile kind of junk), that's if you can even find one. I built a 10.5:1 compression 383, maxed out TBI - 2" big block sized throttle bores with all the mods done, and a cam that was friendly for the computer. I like the fact that all of my factory stuff still works (gauges, cruise control, A/C, all front drive accessories, etc.), no adapters or fancy stuff. If you choose TBI, I recommend you do is your own tuning. I did mine, and I've heard and seen many other TBI trucks that should be on par or out-performing mine. If you're curious or whatever, feel free to send me a PM.

 

[Z Long Bed]

Crustyjunker, What all did you do to your engine? Same block, but all new internals?
I've thought about building the lower end and going with the aluminum Edlebrock heads (for the TBI) and upgrading the throttle body.

Or......going with this...
http://www.edelbrock.com/automotive/mc/crate-engines/chevy-estreet-338.shtml

 

[Eldogg]

I'm finishing up a TBI engine build now for my wife's K2500. 406ci, 5.7 rods, 9.8 to 1 cr, Promaxx vortec heads, Comp 260XFI cam, Edelbrock performer RPM intake with an adapter. I'm focusing on low end torque. Idle to 4500rpm. Its a extended cam LWB 8600 gvw 4l80e truck. I will be tuning it myself using Moates and TunerPro RT.