Mike- your attention to detail leads me to doubt its a wire. I'd check the sensor itself. I've run across knock sensors that were defective from the factory. I recently changed out a sensor from O'Reiley's that had inconsistent ohm readings.

I was in denial that the sensor could be bad for a long while. I tested it it four times- each time it would give the correct reading- if only for a second. It took buying another sensor and testing it to realize that the first one was registering gibberish on my multimeter. I did a comparison of the readings and how hard it was to get the first sensor to give a reading and determined it was bad that way. I think the sensor was dropped hard- or something.

Regardless, if both are new and one isn't working... then I'd suspect the sensor. It's not like you have ignition wires running against it!

BTW- the truck looks great buddy!

 

The Results are In!

The truck made a 300 mile round trip today to get tuned on a Dyno Jet.

First pull:
205hp / 266tq

Last pull:
311hp / 334tq

Engine Specs
- 355ci
- Vortec Heads
- LT4 HOT Cam
- 1.6 Rockers
- RamJet 350
- Coil per Cylinder
- Drive-by-Wire Throttle
- 4L60E Transmission
- 2003 Corvette PCM and Calibration

The horsepower and torque curves are smooth, the engine was responsive to the changes, there were no issues at all with the new ignition system.

The truck feels very powerful on the road and always pulls smooth. The 105hp improvement today was well noticed.

 

Those figures are at the wheels i assume? That should be making a stout 370hp at the flywheel...

 

 

That's some good looking numbers Mike.
That lets me know what I'm looking at when I get on road.
Thanks.

 

what did you do for the cam siginal on the LT1 without a distributer?

 

If you are using a 12200411 pcm it has a tach output that you can set the output pulses in efilive for pretty much any tach. I am running an autometer tach on my 93 Yukon with a genIII 6.0 running a 12200411. my friend swapped a 2001 5.3 in his 95 suburban and I just changed the output pulses to run the factory 95 tach. I believe the 2003+ 1mb pcm's used a serial data line to communicate with the gauge cluster, but I know for sure the 411 pcm's do have an output for speed and tach that are changeable.

 

We pulled it from the front of the engine. No pics, no additional info...until we have a final design.

 

We could do nothing to get the 1990 Trans Am tach and the 89-94 S-10 digital cluster tach to work with the LS1 Corvette calibration. Calibration changes were exhausted. Trust me. The Dakota Digital tachometer calibration box was the ONLY thing that made these tachs work. I set the S10 for a 4cyl input and 6cyl output. I think my buddy set his 90 Trans Am for 2cyl input and 8cyl output...same LS1 Corvette calibration.

If you find another way, build it and sell it for less than $75.00. You'll have something good going for you.

 

did it just display wrong or nothing at all? I read over on LS1Tech that people that had trouble just put a pull up resistor in the siginal line. I guess I have had good luck with it just working, stock 95 truck tach and Autometer tach as well. if you can try it let me know if it works, would be cool since resistors are less than $.75 I hope it's ok to post links here?
http://www.ls1tech.com/forums/showth...t=pull+tach+up

 

Without resistors, no display. With resistors (so many different resistors), tach displayed, but never correctly. I won't be putting any more time into this as the dash is back in the truck and the tach works with the Dakota Digial box.

 

Mike, I posted in a distributor thread on the pacificp.com forum regarding this specific 'Ignition DK' distributor. It was also noted that you were listed in the seller feedback section on Ebay for this unit. My primary concern as posted in that thread was regarding the quality of the generic Tiawan cam sensor in that unit. At the price of this dist. it wouldn't be the end of the world to replace the sensor with a OEM Delco sensor for $40-50 prior to an install.

 

I've not yet had any issues with this distributor or sensor.

 

Their blurb says that it's optical, so getting it to output the LS1 pulse train would require having a new shutter wheel cut. I should think that wouldn't be TOO hard with a waterjet.

For THAT matter, the 24x pulse train could be cut into a shutter wheel for the LT1 opti-spark. Using the CPC ignition gets the high voltage out of the opti which should make it reliable.

 

Also, the CPC ignition allows very large ignition advance angles (>50 degrees) which really help economy with light load.

 

On the LT1 are you running all the stock lt1 sensors? Any updates on the ring yet. Thanks Ed,

 

geez, i wish he'd just post a pic of the timng cover on the lt-1 either way, there is going to be a 496 with this on it in the near future. might even press it back into "street" duty.

 

All LT1 sensors are stock EXCEPT the camshaft, crankshaft, and knock sensors.

For those who will NOT be running speed density only, an LS1 MAF should be used.

I spoke with the machine shop last week. Their CNC equipment has been broken and was expected to be fixed by the end of last week. They are hoping to have the first CNC cut 24x ring done this week. We're waiting on that first ring before the LT1 is buttoned up and back on the test stand. If all is well with the CNC ring, we'll be looking for a few who are ready to try this out on non-LT1 engines.

We're still working on the cam signal pieces for the LT1. It's been a priority, but it all takes time. We had a custom cam sensor made for the LT1. It should work nicely with the prototype optispark replacement pieces.

 

A custom target, custom housing, and custom sensor were made. More details will be available after the pieces are ready for production.

 

I a'm also subscribing to this thread, please keep us posted on the LT1 stuff, I know for a fact, that if you can bring a plug and play kit for the LT1 you will sell hundreds if not thousands of kits, and please don't forget about us Impala people.

Jose

 

Mike, possible release dates. Just a guess, of course!

 

As long as the machine shop's date keeps changing, any date I would give will change as well.

I would like to see the gen1 SBC ready by December.

The LT1 is more involved, so hopefully early 2009.

If you have a 7.4L Vortec engine, "come and get it". Let's start planning your build. The pieces are available.

If you absolutely can't wait for the gen1 SBC, the prototype RamJet 350 is currently sitting on a stand and looking for an owner. Starting at $6500. Price will slightly increase depending on how it is dressed (electronic throttle, front accessories, etc).

 

Wow. Subscribed. This is just too intense.

If GM doesn't stop making these RamJet kits, I won't be surprised if I have more than one vehicle running this LS1 setup someday.

 

The RamJet 350 manifold may not be the only intake manifold to accept the LS type throttle body. It looks like Edelbrock just released an intake manifold ready to accept a Gen3 or Gen4 throttle body. This is part of their Pro-Flo XT package. If my eyes are seeing this correctly, I think the 4-bolt 90mm LS2/LS3 throttle body will fit this (as well as the 3-bolt LS1 Corvette electronic throttle body). Even if I'm wrong, there appears to be enough material there to drill/tap for the Gen3/Gen4 bolt pattern.

And get this! Do you think 90mm is too large for a mild engine? Adjust the calibration so that 100% throttle position opens the blade 75% (for example). Even the throttle body can be tuned!

Oh, and with this intake manifold Vortec heads are not a requirement! However, I think I read that Edelbrock does have a Vortec version available.

 

Your eyes do not appear to deceive you. That is most definitely a LS1 throttle body mount. The black with machined surfaces is a very clean look.

You can tune the throttle body? I'd assume you could tune it for driveability as well. If the engine ends up being a torque monster down low, you could have the throttle open less for more movement on the pedal, and have it taper off to 100% at full pedal travel. That's really interesting.

 

I am subcribing to this post so I ca nsee how it goes with the lt1

 

what are you using to tune with?

 

EFILive

Here are some examples out of the calibration currently in the S10 (2003 Corvette 4L60E).

B2706 - ETC Max Idle Contribution: value represents a percentage of throttle adjustment
B2713 - ETC Max Position for Idle: value represents a percentage of throttle position
B2717 - Minimum Throttle Blade Position: again, a percentage of throttle position
B2307 - ETC Pedal Reponse: table that controls ETC opening versus the actual pedal position and MAP (kPa)
B2702 - ETC Max Position: table that sets maximum throttle position at defined RPM values

Now I'm only speculating, but I see no reason why you can't "scale down" a larger throttle body if necessary.

 

are you using a 2003 file in a 12200411 pcm? I thought that the 411 was only 2001-2002 year?

 

The Corvette was an exception.
- 12200411 through 2003 (512K)
- 1MB LS-type PCM in 2004 (same as GTO)
- E40 ECM in 2005 (same as GTO)
- E38 ECM in 2006, 2007, 2008

 

For the LT1 guys a solution to the cam sensor is going to:

lt1intake.com and modify the intake and use one of the cam sensors in the back of the distributor like the old style...

is it possible?

 

Absolutely. That has been the advice I've given (by email and phone) to those who have been in a rush to get the LT1 up and running with coil per cylinder. It's not something I'm crazy about. It falls under the same category as mounting a buzz saw outside of the engine on the crank. In other words I don't think it's a clean solution, but it would be fully functional and acceptable.

My S10 used to have a modified LT1 intake (TPI electronics, not coil per cylinder). This goes back to 2002 when John was running lt1intake.com. He did great work.



Still waiting to hear from the machine shop for the crank reluctor.

 

I downloaded a 2003 corvette file from EFILive but I cant find those tables.

 

You have one of two problems (or both):
- You did not plug in your interface cable before opening the software (just the USB to laptop, vehicle not required). Why they did this I don't know.
- You do not have a Commercial or Workshop version of EFILive.

If both of those are true, the ETC calibration becomes available under Engine Calibration as a red icon.

 

You are the master. Don't worry.. I won't be another voice!
----------
one question i am interested is:

Is the edelbrock intake manifold an upgrade from the lt1 engine in the end?

 

that must be it, I dont have my cable with me now. I have noticed in the past that sometimes I have a ETC folder and sometimes I dont. I wonder why they did that?

 

this is an awsome thread, but i was just wondering, would it be possible to do this build up with the new stand alone ls7 controller gm has out?

 

Not exactly...
- incorrect crank signal
- incorrect cam signal
- GM LS2/LS3/LS7 harness kit is pinned incorrectly for early engine
- GM kit uses EV6 injectors (LS2/LS3/LS7/etc)
- GM kit is only for manual transmissions
- Electronic throttle body is required
- E67 ECM in the GM kits must be reflashed with a production vehicle calibration to begin with. The calibration loaded in the ECM can not be modified (for example by EFILive). I think the only current E67 ECM V8 vehicles are front wheel drive GM cars (Impala SS, Grand Prix, etc)...and a few hybrid trucks.

 

Someone with EFI Live and who has done this 411 swap can you please load PID CMPRET and upload the scan. I am constantly reading -45.xx degrees. Seems impossible since the car runs and I stabbed the dizzy in 3 times following the proceedure.

 

This thread is unrelated to a distributor application and unrelated to the Express Van calibration. All discussion has been around coil per cylinder and using a true LS1 calibration (Camaro/Firebird/Corvette).

To compare your PID values to another vehicle with the Express Van calibration, please use the sticky thread in the TPI forum for the 411 PCM and a distributor application.

To date, no one else has done the conversion mentioned in this thread.

 

and i doubt anyone will

 

Updates!!
When the S10 was on the dyno, we attempted to get the system into closed loop. We had two things working against us…the O2 voltages were all screwy and the system would never go into closed loop on its own. I now think these are related because with new O2 sensors the system automatically goes into closed loop when it should. So yesterday we put new O2 sensors in the truck and played with EFILive. Here’s the play-by-play.
- modify the LS calibration to use the Injector Bank Assignment values from the 2001 Express Van
- monitor the PIDS: Heated O2 Voltages, Short Term Trims, and Long Term Trims
- open the bi-directional control panel to have access to manual control of Open/Closed Loop
- start the engine, monitor data
- O2 voltages look good (old sensors were both bad – I should mention they were in the bungs when the bungs were welded to the pipes. Mental note – $100 mistake – don’t do that again)
- Watch A/F with the LM-2 (wideband controller)
- Play with throttle until there was a consistent 13.0 A/F
- Force Closed Loop
- Immediate adjustments to short and long term trims begins
- A/F quickly changes to about 14.7

I still want to spend more time with this using the RoadRunner. It would have been better to adjust the VE values to make the engine run rich in open loop and then force closed loop. Regardless, I was able to accomplish the same thing several times by playing with the throttle…an indicator that we still have more tuning to do. However, it was difficult to find an operating condition outside the 14 A/F range, so the tune is close.

Why is this significant? The LS firing order is different than the Gen 1 and Gen 2 engines. The injector bank assignents for the LS are different. And that means that, in close loop, the fuel trims would not work correctly because fuel would be added/removed from both sides of the engine in an attempt to correct air/fuel on any one bank.

Reluctor Update
Machine shop is looking into an alternative way of cutting teeth, and I'm waiting for an update. Some are asking, "What is the expected cost and availability?" We're asking the same question.

 

Nice. I've been thinking about something like this myself on my 383 HSR. Mainly just converting it to coil per cylinder and the function of being able to tune the 4l60e or 4l80e (whichever one I choose to run) easily in my truck.

Keeping the TPI parts(throttle body, etc) would this still work correctly or would we all have to upgrade the gauge cluster, etc?

 

TPI sensors are compatible. Electronic speedometer is compatible. All other gauges are independent of the ECM/PCM.

Tachometer may require a Dakota Digital converter. You will find this to be true with the Corvette calibration (electronic thottle). I can't speak for the Camaro/Firebird calibration (cable throttle - TPS and IAC), but do know it outputs a different tach signal. I don't know why they're different, .but the differences seem to go beyond what you can modify through the calibration.

Yes, there are changes you can make to the calibraion, but I now know of two people who have tried making the Corvette calibration cooperate with an older GM tach and there was no combination of resistors, etc that could be applied to the signal to make it work. If anyone has found a cheaper alternative to the Dakota Digital converter to fix to this, please post the details. Please trust me on this...significant time has been put into this with no other success.

I've not heard of similar problems with the guys swapping Camaro/Firebird LS1 engines into 3rd gen cars. There's something unique about the LS1 Corvette tach.

 

Well, right now, its driven off of the distributor for the tach. I don't have a tach on my 1990 C1500 gauge cluster so I wonder how I would run one.



Do we have an estimated price for the wiring harness conversion?

 

A tach is not required, but you could probably use any aftermarket tach. The Dakota Digital box may or may not be required.

A stand alone harness would run about $600. I'm working out the details for a plug and play LT1 harness. It would require the complete removal of the original LT1 fuel injection engine harness and the installation of the new fuel injection harness. This type of harness will probably be priced around $700.

 

Yea, I do have an aftermarket tach one right now ran to the distributor.


If I was to do this, I guess it would be easier to do a full harness swap rather than dealing with the gauge issues with running a "e" transmission rather than the 700r4. The governor calibration is just too much of a hassle when its a click away these days.

Or a standalone 4l60e harness for the transmission would be my only other option than your harness.

 

The S10 had a fresh 700R4 build to handle the 400hp. When I set my mind on the LS1 PCM, I pretty much welcomed the extra work and expense of the 4L60E. As you mentioned, the 700R4 still required some messing around with governor weights as it would never shift at full throttle. I absolutely love having the 4L60E in the truck.

 

Absolutely. Is there any luck in your company making a stand alone tcm (transmission control module) for the 4l60e or 4l80e with TPI electronics?

 

No, absolutely no chance of that.