new member with a 97 Tahoe with a 383 vortec - with some modifications...

Hello, been lurking around for a while, just found out the way to post :-) my intro

so, I have a 97 Tahoe (2 Door), with some modifications on the engine, transmission, axels, suspension & tires.

I live in the middle east, but I am a westerner, I use my Tahoe for camping trips & desert dunes crossing....good fun indeed.

I have been doing a lot of reading on the I Gen vortec EFI system and now managed to get Jet DST software.

So now, I am looking forward to learning some more and help others where I can.

here is a list of the Mods done to my truck

383 SBC Vortec
Compcams 12-422-8 CS XR270HR-10
STS performance 1.6 rockers
Edelbrock 60989 heads 200cc
Speed-Pro Hypereutectic Pistons H859CP30 12cc
CompCams-15853-16 short travel Hydraulic Roller Lifters
Manley 25734-16 Pushrods- 4130 5/16 7.100
High Volume Oil and Water pumps
New Delco MPI Injector Spider conversion Assembly
160* Thermostat
BBK 80mm throttle body
K&N Stage 2 intake
New Spark Plugs Champion RC12YC and Accel 9042 Extreme Cables.
Delco distributor + gear
Summit Racing SUM-29006B-C MAF sensor
Thorley Headers 1 5/8" ID and 2 1/2" ID THY-301Y-FED
Gibson 315501 catback exhaust and No Cats

On the 4L60e
Corvette 1-2 servo
Beast sunshell
HD TransGo Kit & sonnax servos from Dana Wilkes of Pro-Built in CA
stock S10 Blazer Torque Converter

315/75-R16 Cooper ATR Tires
4.88 Motive gears
Detroit -no spin- locker on the rear 10 bolt
Bilstein shocks all around
add-a-leaf from Rough Country to lift the rear 2"
Uprated GL torsion bars (off a 97 suburban), cranked 2" - hard on the road, awesome on the dunes

that's it for now

Cheers
MZ

Quote:

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Originally Posted by MazingerZ

Hello, been lurking around for a while, just found out the way to post :-) my intro

so, I have a 97 Tahoe (2 Door), with some modifications on the engine, transmission, axels, suspension & tires.

I live in the middle east, but I am a westerner, I use my Tahoe for camping trips & desert dunes crossing....good fun indeed.

I have been doing a lot of reading on the I Gen vortec EFI system and now managed to get Jet DST software.

So now, I am looking forward to learning some more and help others where I can.

here is a list of the Mods done to my truck

383 SBC Vortec
Compcams 12-422-8 CS XR270HR-10
STS performance 1.6 rockers
Edelbrock 60989 heads 200cc
Speed-Pro Hypereutectic Pistons H859CP30 12cc
CompCams-15853-16 short travel Hydraulic Roller Lifters
Manley 25734-16 Pushrods- 4130 5/16 7.100
High Volume Oil and Water pumps
New Delco MPI Injector Spider conversion Assembly
160* Thermostat
BBK 80mm throttle body
K&N Stage 2 intake
New Spark Plugs Champion RC12YC and Accel 9042 Extreme Cables.
Delco distributor + gear
Summit Racing SUM-29006B-C MAF sensor
Thorley Headers 1 5/8" ID and 2 1/2" ID THY-301Y-FED
Gibson 315501 catback exhaust and No Cats

On the 4L60e
Corvette 1-2 servo
Beast sunshell
HD TransGo Kit & sonnax servos from Dana Wilkes of Pro-Built in CA
stock S10 Blazer Torque Converter

315/75-R16 Cooper ATR Tires
4.88 Motive gears
Detroit -no spin- locker on the rear 10 bolt
Bilstein shocks all around
add-a-leaf from Rough Country to lift the rear 2"
Uprated GL torsion bars (off a 97 suburban), cranked 2" - hard on the road, awesome on the dunes

that's it for now

Cheers
MZ

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Welcome!!

Nice sounding rig with a lot of nice modifications. If it were mine I probably would have gone with the 170cc intake runner heads(have a set of them that I had on my 350 and the stock intake even a marine just does not flow enough air to use the 200cc ports effectively), a 9.5" 14-bolt and a 4L80E. Making it a torque monster and practically bulletproof. Before you tune that Black Box you might look into an 0411 swap. I swapped my 1997 Express to one and LOVE it compared to the Black Box. I am in the process of swapping over to the EFI Connection 24x system with 5.3/6.0L truck coils. I am running the L31 marine intake and have dreams of a 383 or 406 someday to pull my ~6,000 lbs 23' travel trailer.

Now onto the problem I see with your combination. When you start datalogging I expect you are going to see injector duty cycle well over 100% and a general shortage of available fuel. I tuned my buddies 1998 K1500 truck with a similarly spec'd 383 and it was out of fuel by 4,500 rpm and hit 125% duty cycle by the 5,500 rpm fuel kill. He had Ebay 200cc aluminum heads and a slightly smaller comp cam. 212/218 @ .050, .487/.495" lift on a 110* LSA.

Quote:

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Originally Posted by Fast355

Welcome!!

Nice sounding rig with a lot of nice modifications. If it were mine I probably would have gone with the 170cc intake runner heads(have a set of them that I had on my 350 and the stock intake even a marine just does not flow enough air to use the 200cc ports effectively), a 9.5" 14-bolt and a 4L80E. Making it a torque monster and practically bulletproof. Before you tune that Black Box you might look into an 0411 swap. I swapped my 1997 Express to one and LOVE it compared to the Black Box. I am in the process of swapping over to the EFI Connection 24x system with 5.3/6.0L truck coils. I am running the L31 marine intake and have dreams of a 383 or 406 someday to pull my ~6,000 lbs 23' travel trailer.

Now onto the problem I see with your combination. When you start datalogging I expect you are going to see injector duty cycle well over 100% and a general shortage of available fuel. I tuned my buddies 1998 K1500 truck with a similarly spec'd 383 and it was out of fuel by 4,500 rpm and hit 125% duty cycle by the 5,500 rpm fuel kill. He had Ebay 200cc aluminum heads and a slightly smaller comp cam. 212/218 @ .050, .487/.495" lift on a 110* LSA.

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thanks for the welcome and feedback, will dig into the injector cycle topic, I never thought about that, will check my scanner to see what's going on.

when I am out in the desert on long or soft dune, the engine sees short bursts of 4500-5500 RPM on 4L, it has been ok so far. I have the updated Delco injectors

Might get it dyno'd just to see what's going on.

cheers
MZ