Looking to build a good street setup

[Roadrunner]

I'm looking at building a new power train/truck. I have been running the gmt400's for a few years now and generally like them overall, but still haven't found a setup I really like. So far I've gone through a 98 vortec and a 93 tbi.

I started with the vortec first, bought a clapped out truck and had the engine and trans rebuilt. Long story short I drove the truck for 2 years and put about 40k on it. I ended up wrecking the truck. The engine and trans builds were probably not best as I had a list of crap to fix to get it rolling good when I got it back, but once straight it was a good truck.

After wrecking the 98 I picked up a 93 that had a bad trans with a 305. After driving the 305 a bit I decided the little 305 ran too good to swap the vortec into. So I built the trans and ran it for about a year that way. Along came a 350 tbi motor that had builder tags on it and a low mileage truck. So I swapped the 305 for a 350.

All said and done it took about a year to get this motor running good. It still has a few misc things to do to get it dialed in, but it's running pretty good now.

Here is where I'm looking to get to with my truck. First I need to go to a 4l80e instead of the vulnerable 4l60e. The one I built for the 93 works really well for the most part but I do tow and carry around a bunch of tools so it's probably not long for the world with the way I work the truck.

Next I need to build some small block power 190 horses just doesnt cut with the tbi. The low end grunt is great but gas mileage and low output is a bit hard to swallow for me. Along that note the vortec wasn't a whole lot better either but the mileage was better.

So here I am thinking of swapping the vortec in and building a 4l80e to go with it. At some point I'm probably going to go to the 3/4 ton 4 door chassis if I can find one that's not hammered. Probably going to do a 411 swap as well so I can tune easier and leave an ls option in the future if I cant get a small block I like going.

I guess right now I'm looking at building a small block that keeps the power band low most of my driving keeps the motor between 1800 and 3500 rpms with lots of 3/4 shifting. I'm in wide open space at 80 mph surrounded by mountains.

Looking for recommendations on a setup that going to make me happy in the end.

 

[89GMCJOHN]

Since your not very specific on your HP , TQ or mileage needs I would assume being in the mountains you need grunt. You cant have everything (mileage,hp,tq lol) but I am thinking a marine cammed 350 build with vortecs will get you 345 HP @5,000 RPM 396 LB-FT TORQUE @3,600 RPM for your mountains . If you drop a set of really good aftermarket heads on it maybe 10-15 more horse and maybe 10 more ft lbs. So 155 more horsepower on top of your current 190 and 80 ish more ft lbs might do the trick . P.s. idles like a sewing machine .

 

[Roadrunner]

I think that about sums up what I'm after. I was hoping that the vortec motor could get me there with a bit of work. 15 mpg would work out okay for me and that seems about where the tbi is now if I'm easy on it. It might be a little better now that I fixed a leaky injector but I'm not holding my breath.

I'm hoping a warmed over vortec will fit the bill.

 

[Gramps]

I used a comp roller cam, (have to look up the number) with oem lifter retainer spider, stock vortec roller lifters, hybrid tbi/vortec heads, on a .040 tbi block. With stock type dishes pistons coming in right around 9.5:1. Stock tbi intake, 350 tbi unit with a few mods and 454 injectors and 14psi fuel pressure. This was All controlled by the stock ecm. Pulled 300hp/385tq on the dyno, the tq was over 300ftlbs I want to say by 3000rpm only pulled it to 5500r.

 

[Roadrunner]

One of the reason I'm looking at going away from the tbi is the obd1 system it has. It's taken me a lot of work to diagnose some simple issues and at times made me want to set the thing on fire. So far when the truck has run poorly no check engine light will come on.

I still have a bit of hesitation when I turn left or when warm from a stop that is more than 2 minutes long. I was sold out on the simplicity and robust nature of the obd1. I think the obd2 is more useful for me as the vortec once straight ran well and never missed a beat.

I do really like the pull out of the hole with the tbi though but after that it just has no legs. I even considered putting a turbo setup to help up top but the ecm and tuning are prohibitive to doing so with having to burn chips, or do the ebl flash thing.

 

[Schurkey]

One of the reason I'm looking at going away from the tbi is the obd1 system it has. It's taken me a lot of work to diagnose some simple issues and at times made me want to set the thing on fire. So far when the truck has run poorly no check engine light will come on.

I still have a bit of hesitation when I turn left or when warm from a stop that is more than 2 minutes long. I was sold out on the simplicity and robust nature of the obd1.

What scan tool are you using?

 

[Roadrunner]

The old paper clip trick and a dvmm. Wish I had one that did the early obd stuff but I dont.

Recently I had to chase down a bad injector seal and had 2 different chinese injectors in the tbi. The bottom oring split and was choking the fuel feed ports. Everything looked good with the spray pattern in the shop but out on the road it had no power and missed really bad. It took a lot to get to that point though.

Right now I'm thinking of going to the vortec , 411, getting it running good and figureing out the tuning stuff. I saw some where you can tune the 411's with tunerpro and ls link or something to that effect.

 

[Schurkey]

It's taken me a lot of work to diagnose some simple issues.

What scan tool are you using?

The old paper clip trick and a dvmm.

What sense does it make to complain about the difficulties you're having with OBD-1/TBI if you're trying to do diagnosis without a scan tool?

OF COURSE it's taking a lot of work. That's the purpose of the scan tool--to save time, money, and effort by providing accurate and reliable results quickly.

For example, your blocked injectors would have shown up as lean mixture on the O2 sensors, and rich-command on the fuel trims. You'd have seen lower-than-expected vacuum at cruise with the MAP sensor, and--maybe--higher than expected throttle position. If your fuel pressure and volume tested OK, that'd take you directly to the injectors.

 

[PlayingWithTBI]

I even considered putting a turbo setup to help up top but the ecm and tuning are prohibitive to doing so with having to burn chips, or do the ebl flash thing.

The EBL Flash2 is a giant step up from the older ECMs and has the capability of controlling boost and nitrous, it has a built in data logging and troubleshooting app called the WUD (What's Up Display) but, keep in mind it doesn't control electronic transmissions like the 4L60E (wish it did). Here's a screen shot from the WUD running with a WBO2 sensor

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[RDF1]

I think a vortec 5.7 with just a good cam/springs and a turbo would get you somewhere. Keep it from shifting 3-4-3-4 constantly.
Along with the LS1 PCM swap, you would have everything you need with a custom operating system to run the boost.

I towed with a turbo LQ4 for years and loved it. 2000 rpms at 70mph and it chugged on along like a diesel with just 6-8 psi.