Marine Intake is on and running.

[Fast355]

What year 4L80e are you using Fast?

2002

[Fast355]

Someone got ambitious and datalogged after adding 2° of timing across the board under load and 2° more in the heavy load, lowest rpm area. Still massaging a lean spot caused by the intake but this thing pulls harder now than ever. The only time I am seeing any knock retard is at the lowest speed the converter stays locked in overdrive while aggressively opening the throttle. No timing was added in the trouble area but I am considering adding a little more burst knock back in and around that area to prevent it from doing it. I have also considered slightly raising the lockup mph to keep the engine from seeing that load.

[Fast355]

I raised the TCC lockup to 60 mph and the lockup induced lugging and spark knock is no more. I am able to run a 13.4:1 air/fuel ratio and 28* total timing from 3,500 rpm though 5,500 rpm in 1st and 2nd gear. I found through testing the CCOT logic is actually very accurate. I have the EGT limit set to start brining in the CCOT at about 1,400* and have the AFR timing compensation map setup to pull up to 8* of timing as the CCOT air/fuel ratios increase. The maximum enrichement is set for 1,650*F estimated EGT and the actual EGTs run about 1,600 on prolonged WOT and actually start to drop as the air/fuel mixture richens to its maximum of 10.8:1 at about 85 mph. With the timing retard I am not seeing knock going into 3rd gear either. So basically its working as intended now.

Also managed to get a piece of 3.5" aluminum tubing mandral bent in the shape of my PVC intake and wrapped with a heat insulator. We tig welded on a couple of aluminum tabs to hold the intake on the fan shroud. I am seeing 98 KPA on a 101 KPA baro reading now and spikes over 250 gms/sec airflow.

Someone is also well over 300 RWHP now with his L31/4L80E/9.5" 14-bolt driveline. This person also gained 40 ft/lbs of torque at 1000 rpm at the wheels by adjusting the timing map in that area using a locked 3rd gear pull on a dyno. Talk about a throttle response boost. Someone drifted his Express around a 90* right hand corner afterwords without intending to.

[EagleMark]

Someone is also well over 300 RWHP now with his L31/4L80E/9.5" 14-bolt driveline. This person also gained 40 ft/lbs of torque at 1000 rpm at the wheels by adjusting the timing map in that area using a locked 3rd gear pull on a dyno. Talk about a throttle response boost. Someone drifted his Express around a 90* right hand corner afterwords without intending to.

Dam! Who might this someone be? Can you get him over here to tell us how?

I like the toque curve, thius would explain the express van drifting?

[Fast355]

Dam! Who might this someone be? Can you get him over here to tell us how?

I like the torque curve, this would explain the express van drifting?

The little 4x4 comp cam and marine intake are likely the biggest part of the equation. Followed by lots of little stuff to the setup and tuning.

I have a crazy aggressive timing curve that works well for this setup. Running no less than 10° @ 1000 rpm except during burst knock retard, 24° by 2,800 and 30° total by 4,600. I can't wait to see how it reacts to the tri-ys! I have seen milder engines gain 20 hp and 30-40 ft/lbs at the crank from a simple set of long tubes. That and it needs 4.10s badly so much so that I wish I had gone with a smaller, lighter, higher STR 2,800 rpm converter.

[Hog]

Nice package there Fast, you've got LS1 power from the GEN !E Vortec, plus its running through the HD drivetrain, better than LS1 power!

That lean spot you're speaking of, was it a lean bog when cold? I myself had some decent lean bogging upon throttle application after the swap. AT least 3 other guys I know have had the same issue, exageratted when cold, not as bad when engine is warmed up.
There are no "throttle stomp" or "pump shit" in the blackbox PCM, IIRC I did some major VE tuning as a work around.

Do you think that the stock L31 intake manifold are major obstacles to making power on the L31?

Cant wait to see after the Thorleys are installed.

Someone asked about prices, I paid around $600 for mine, it came with brand new parts to assemble the USCAR connectors, colour coded wires, wiring diagram, all gaskets for instal, marine t-body, marine IAT/MAP sensor, cleaned and flowed marine injactyors(25 lb/hr@43.5psi), machined for Vortec bypass, a couple new brass waternecks, new pig iron quick connect heater connector, it was a very good kit.
My retrofit was done for under $1000 including tuning. IO cant remember if my Tunercats OBD2 tuning system was in that $1000 or not. I paid $330 for it during a group discount.

Good work man, that torque curve is flat, tough to pic a stall speed with that flatline. Good problem to have.

peace
Hog

[Fast355]

Nice package there Fast, you've got LS1 power from the GEN !E Vortec, plus its running through the HD drivetrain, better than LS1 power!

That lean spot you're speaking of, was it a lean bog when cold? I myself had some decent lean bogging upon throttle application after the swap. AT least 3 other guys I know have had the same issue, exageratted when cold, not as bad when engine is warmed up.
There are no "throttle stomp" or "pump shit" in the blackbox PCM, IIRC I did some major VE tuning as a work around.

Do you think that the stock L31 intake manifold are major obstacles to making power on the L31?

Cant wait to see after the Thorleys are installed.

Someone asked about prices, I paid around $600 for mine, it came with brand new parts to assemble the USCAR connectors, colour coded wires, wiring diagram, all gaskets for instal, marine t-body, marine IAT/MAP sensor, cleaned and flowed marine injactyors(25 lb/hr@43.5psi), machined for Vortec bypass, a couple new brass waternecks, new pig iron quick connect heater connector, it was a very good kit.
My retrofit was done for under $1000 including tuning. IO cant remember if my Tunercats OBD2 tuning system was in that $1000 or not. I paid $330 for it during a group discount.

Good work man, that torque curve is flat, tough to pic a stall speed with that flatline. Good problem to have.

peace
Hog

I was able to tweak on the end of injection timing and accelerationenrichment tables to make the lean spot vanish with a cold engine. The latest lean spot was due to the CAI leaning out the tune slightly. Added between 1% and 5% to the MAF table via datalogging amd its now just about perfect. In this cool weather it likes spinning the 255s on it. I think the factory intake, throttle body and intake ducting are all major restrictions to power once a decent cam and exhaust is installed.

[PJG1173]

Fast,
which comp 4x4 cam are you using the 260, 270 or 280? with the 280 cam I can't get more than 24*@3200 without knock on my TBI converted vortec 355.