Need New Engine...and Help

Hello all,
New member and I am glad that I found this site. I have a project and I need some help. 1995 Chevrolet Silverado 1500 Z71. Engine is blown but has brand new 4L60e trans. I would like to replace the engine with something with more power. This will be a toy hauler truck. Looking for 300-350hp 350-400 torque. Looking at crate engines from various venders is leaving a lot to be desired as far as the power I want goes. Is it possible to use a 1996 and later vortec engine and switch the manifold and run the tbi I have currently? I really would like a 4 bolt roller cam engine with better flowing heads. Are there better ways to go about getting the power i want? Just wanting to test the waters here for some suggestions.

Thanks Guys

The TBI system tends to limit peak power. The largest diameter throttle body is from a 454 Chevy. With this and matching injectors you may get close to the power you want. You can buy intake manifolds with a carburetor flange that fit the Vortec heads then use an adapter to run the 454 throttle body. Of course you can use a roller cam with the Vortec block and you'll want to switch to better exhaust to complement the other changes. When all of these parts are put together you will have to make or buy a custom chip because the engine you want to build is far from the mild 350 that came in the truck originally so you'll need some equipment to view ecm data at the minimum.

There are many engine options to get you the performance your targeting.

One option is to modify the PCM you have for Multi Point Fuel Injection (MPFI) and install a Bone Stock Vortec 350 with a Bone Stock Vortec 350 intake. Two injectors (TBI) are good, eight injectors (MPFI) is better.

Another option is to install a Vortec 4 barrel carburetor intake with a TBI adapter plate on a crate Vortec 350 engine.

Yet another option is to install a Vortec Roller Camshaft assembly into a stock 350 TBI engine, unfortunately not ALL TBI 350 engines will accept the Vortec 350 Roller Camshaft assembly. Which leads to the option of using a Bone Stock Vortec 350 short block assembly with 350 TBI heads. This option might not offer the best ALL OUT performance, but has the fewest headaches and could be the lowest cost "performance" option.

For my 1993 K1500 engine replacement, I was lucky and was able to install the Vortec 350 roller camshaft assembly into a re-manufactured TBI 350 engine. I modified the 350 TBI intake to accept a 670 CFM throttle body with "Cop Car" injectors. I custom tuned the "CHIP" myself. I did not Dyno the K1500, but the 0 MPH to 60 MPH time was about 7 seconds, not bad for a 5200 lb pickup. Because I did all the labor myself, the total cost of my K1500 engine project was less than $1500 (including a new fuel pump). I'm sure others could spend more $$$ and get more performance?

dave w

Thanks for the responses.
I was doing some research last night and I think I may have a starting point. Chevrolet performance 4 bolt roller cam 350 with vortec heads. http://www.jegs.com/i/GM+Performance...30283/10002/-1
Replace with cam.
https://www.summitracing.com/parts/lun-20080660
***use tbi to vortec intake
https://www.summitracing.com/parts/nal-12496821

Do the ultimate tbi mods. machining the top "lip" of the throttle body and the throttle shafts.
Install 18 pound spring in the fuel pressure regulator.
Replace y-pipe with better one.
Short tube headers. 1 5/8 primaries.
Cat delete and dual back.
Replace fuel pump with the vortec fuel pump.
Find someone to make a performance chip based on the mods.
If I have $ left maybe have Throttle body bored and machine shop work on the heads.

***Reading up on the tbi to vortec intake, people seem to complain about the engineering. Many complaints about having to use this adapter and that. It was stated above to use a vortec carb intake and use an adapter. Would this save me a big headache going this route? Does anyone have part numbers or links to that setup?

I am trying to keep a budget of ~$4500. Is what I listed above a smart way to go about this build or is there a much better way to do this.

I was unaware of the "cop car" or "police special" injectors. I did a brief online search and only found rebuilt ones for sale. Can these be found "new" and do they simply replace the stock 350 tbi injectors or are there modifications involved?

Thanks!

I agree, there are several options. Basically TBI get a "Bad Rap" because it can be VERY Challenging to "TUNE"!

I don't always agree with the phrase "Ultimate TBI Mods", because there is truly ONE ULTIMATE TBI MOD, it's the CHIP

dave w

roger that dave,

just calling it that as that is what I have seen it called on the tbichips website and the youtube.
as for having a chip made, who would you guys suggest? i have heard of tbichips (harris performance) and ed wright.
I am admittedly not an efi guy, all of my experience has been with carb engines and 90% of that has been marine 2 stroke outboards. Always like learning new things so eventually I would like to learn how to tune this thing but to start off I might need someone to do it or at least walk me through it.

again thanks for the insight!

Quote:

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***Reading up on the tbi to vortec intake, people seem to complain about the engineering. Many complaints about having to use this adapter and that. It was stated above to use a vortec carb intake and use an adapter. Would this save me a big headache going this route? Does anyone have part numbers or links to that setup?

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Some people, myself included, believe the commonly available TBI to Vortec intake manifold is a copy of an OEM intake installed on vehicles which were exported in the mid-'90s. As such it offers relatively small peformance gains. It's possible and effective to increase the diameter of the opening but most folks don't opt for this solution. Instead they use an adapter to bolt on a 454 TB. The adapter spaces the TB up and does allow some cross-bore airflow but it's not the best solution.

The carburetor manifold with adapter is method to allow maximum airflow possible. With a TBI in a street application it can be important to balance airflow with air temperature and plenum size. There are several ways to do this but a good one might be to find a manifold with a smaller plenum size. There are race manifolds for Ford or Holley 2bbl intakes which can be a good choice with an adapter. Edelbrock 2912 is one possibility.

Another option is to use a spread bore Quadrajet style manifold with an adapter. These manifolds typically provide some coolant heating and do not raise the TB as far out of the engine valley. There are aluminum and high-rise cast iron versions. Edelbrock, Weiand, and Professional Products all make manifolds in this category.

Quote:

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Originally Posted by 1project2many

Some people, myself included, believe the commonly available TBI to Vortec intake manifold is a copy of an OEM intake installed on vehicles which were exported in the mid-'90s. As such it offers relatively small peformance gains. It's possible and effective to increase the diameter of the opening but most folks don't opt for this solution. Instead they use an adapter to bolt on a 454 TB. The adapter spaces the TB up and does allow some cross-bore airflow but it's not the best solution.

The carburetor manifold with adapter is method to allow maximum airflow possible. With a TBI in a street application it can be important to balance airflow with air temperature and plenum size. There are several ways to do this but a good one might be to find a manifold with a smaller plenum size. There are race manifolds for Ford or Holley 2bbl intakes which can be a good choice with an adapter. Edelbrock 2912 is one possibility.

Another option is to use a spread bore Quadrajet style manifold with an adapter. These manifolds typically provide some coolant heating and do not raise the TB as far out of the engine valley. There are aluminum and high-rise cast iron versions. Edelbrock, Weiand, and Professional Products all make manifolds in this category.

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I also feel the GMPP Vortec TBI manifold is a copy of a factory manifold. Either the Export manifold or the GM Marine manifold. I have seen a very similar manifold used on Crusader 305 and 350 engines and they are stamped Crusader.

In the past a 2912 ran very well for me. I used a water heated Holley Projection TBI to 2bbl carb adapter that was available at the time.

Quote:

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Originally Posted by DixieChicken

.
as for having a chip made, who would you guys suggest? i have heard of tbichips (harris performance) and ed wright.
I am admittedly not an efi guy, all of my experience has been with carb engines and 90% of that has been marine 2 stroke outboards. Always like learning new things so eventually I would like to learn how to tune this thing but to start off I might need someone to do it or at least walk me through it.

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I would recommend using Wide Band O2 Sensor (WBO2) "Tuning"! Here is a link to WBO2 tuning that has helped several gearhead-efi members with TBI tuning: http://www.gearhead-efi.com/Fuel-Inj...g)-Spreadsheet

See WBO2 tuning screen shot below.

I wonder if TBI Chips and Ed Wright use WBO2 tuning? It's likely they don't use WBO2 tuning, which might be why several gearhead-efi members are reluctant to recommend their services?

dave w