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Discussion Starter #1
Okay, after all the battles (mostly lost) trying to tune the LLT, I have offically given up. We started working on seeing what it would take to get the ECU from a 2012 to work with the LLT, but it was just too big a project. So...

In October I took ownership of a 2012 2LT/RS LFX. GPI (Gwatney Performance Innocations) was able to immediately connected to it with EFI Live and is working with them on a few tweaks for the transmission connectivity.

In the next update I will let you know how the stock tuning went.. After that we will start the twin turbo build info.

Before we could do any of that they had to take all the good parts off my old car to swap what we can. I'll post a link to my classified ad for the parts I can't use (like ported heads, ported intake manifold, shorty headers, intake isolator, etc..), so keep an eye out for that you LLT guys.

And now for some pics of the new ride.

01-Car.jpg

02-Car.jpg
 

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Very cool Gretchen. I'll respect your privacy. Thank you for posting this over here.
 

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OK Ill bite what happened to the old ride.
 

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Discussion Starter #5
Yes...I look forward to hearing more about your project. I would be interested in your intake isolator...it's the one thing I don't have...pm me with a price if you're ready to part with it. Envy would be proud to wear a piece of Gretchen...lol :D
Sure, be glad for you to have it. We are working on a solution to get some more fuel to the LFX. If that works we will probably build one for the LLT and I'll need the isolator for a pattern. After that, it's all yours.
 

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Discussion Starter #6
OK Ill bite what happened to the old ride.
We never could tune it. Got it up to 500 on the dyno ONCE! It was a pain not being able to see the logs as we were making the pulls. Ended up breaking the ring lands on two pistons right before CFest. Since neither of the two tuners were interested in giving us a way to see the logs or make tweaks ourselves, we gave up on the LLT.
 

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Discussion Starter #7
Sorry about the delays in updating. Got really busy at home and work.

Basically, after messing up the LLT and my horrible runs at CFest, I decided to buy a new LLT motor, build it for more power, and try to find a better tuning solution. We had no luck on the tuning, so we thought about chancing the ECU for the Delphi unit used in the LFX. Unfortunately, that was going to be expensive. So, GPI got me a low mileage 2013 and I traded my 2010 for that. We put the new LLT engine in the old 2010, along with the rest of the drive train from the 2013. It sold the day they put it on the lot and is still running well.

We then put the transmission, driveshaft and differential from my old build in this new car and ordered some 10:1 compression ratio Diamond forged pistons. Everything else on the old LLT motor looked great. The bearings looked brand new.

We have a local shop that builds for Nascar and NHRA. He's been consulting with us and he said the design of these LLT/LFX motors is amazing. Rods and crank are much better than stock LS parts. He loves the design of the block with nice think walls and good webbing. He thinks they'll hold quite a lot of power if we don't do something stupid.

I'll get you some pics of the intake system he designed for us if I get a chance tonight. Otherwise, it will probably be this weekend.
 

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Sweet man, glad to hear you didn't give up.
 

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Discussion Starter #9
Updates coming soon. Making just under 600 RWHP and over 600 RWTQ on an unlocked converter. New multidisk converter on the way.
 

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Discussion Starter #10
Well, I didn't want to post until we had the biggest issue resolved, but looks like that's not going to happen soon.

Both EFILive and HPTuners have some missing tables for the E39 ECU. It isn't an issue on the NA cars or even centri FI that don't have a torque converter, but for me it has been a killer. We can command open throttle but it really won't open all the way until it reaches a certain RPM or MPH. That means I can't get my throttle to open more than about 40% at launch and it takes about 2 sec. for me to get it to open all the way. This is costing me about .3 on the 60' and probably over .6 on the 1/4th.

HP just had their lastest release and there were no new tables for my ECU. I still haven't heard anything about the next release of EFILive, so can't say when we might get this fixed.

However, we move one. Driveability tuning should be finished this weekend. Cage goes in next week. After that we put her on the dyno and see what she can do. Don't know when the multidisk converter will be ready, but hopefully by late September when I hope to hit the track again. Still hoping to hit a 10.5 or better pass, but that may not happend with the throttle issue.
 

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Well best of luck. I know my J-body PCM is still missing some of the tables in HPTuners, and it was one of the first PCM's supported back in 04-05.

So....what are you running in the 1/4?

Can you go into the desired throttle area and change the numbers? I know you can completely mess up the PCM and brick it changing these values....

BUT can you change the Desired Area Axis type from VSS to RPM? I know on 2010s you can.


Also, did you change the Max torque setting on the traction control? 2010s are set at 479 ft/lbs.


DID YOU DISABLE or CHANGE THE ETC LIMIT! under Tip-in Limiting?


Just some random thoughts after looking at some tunes on the HPTuners repository.
 

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Discussion Starter #12
Well best of luck. I know my J-body PCM is still missing some of the tables in HPTuners, and it was one of the first PCM's supported back in 04-05.

So....what are you running in the 1/4?

Can you go into the desired throttle area and change the numbers? I know you can completely mess up the PCM and brick it changing these values....

BUT can you change the Desired Area Axis type from VSS to RPM? I know on 2010s you can.


Also, did you change the Max torque setting on the traction control? 2010s are set at 479 ft/lbs.


DID YOU DISABLE or CHANGE THE ETC LIMIT! under Tip-in Limiting?


Just some random thoughts after looking at some tunes on the HPTuners repository.
Yeah, we have tried all of that. It appears that there is a limit on actual throttle position based on the frequency of air across the MAF, but we aren't sure. It appears that the NA cars with the E39 have that set at 100 KHz, but in the FI cars it is set at 200 KHz. We've tried changing that value and it fixed the issue at WOT but drivability was crap. So, we think there are some TM tables that reference the frequency that we don't have yet.

As for 1/4 times well...we should have gone forged rods when we did the pistons. Made 1/8th at 102 mph, engine gave up at 103 and coasted in with a 11.49 ET. Guessing that was a 10.9x run. Losing .3 on the 60' and it takes about 2 sec for throttle to open all the way. Sure hoping I can get a 10.5 or better when we get the tune right.
 

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Discussion Starter #13
Drivability tuning is done. Ryan (the builder/tuner) says it now feels stronger on 17psi that it did on the old motor at 20psi. Won't really know until we get it on the dyno and to the track though.

The old piston/wristpin setup was about 43 g/cylinder heaver than stock. The new setup is 21 g/cylinder ligher than stock. We went with jetted rings and they seem to be doing the job.

Roll cage work is starting Friday (I forgot to take them the rear seat so it was delayed). They may get it on the dyno before then, but more than likely it will happen after it is back from the fabricator.
 

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Does the pistons have Vertical Gas Ports in them? I haven't heard the term Jetted Rings before...

I copied this since I think we are talking about the same thing....
Taken from Wiseco's FAQ:

Q. What are gas ports and when should they be used?

A. Vertical gas ports are primarily used in drag race applications. Lateral gas ports are more often used in circle-track and road-race applications where carbon build up can occur. When gas ports are used, pressure is directed to build up behind the compression ring and seal it against the cylinder wall. This helps prevent ring flutter and extends the power curve upward in the RPM range. Vertical gas ports have the holes drilled from the deck of the piston into the top ring groove and behind the ring. Lateral gas ports are drilled through the bottom side of the top land and extend to the back wall of the ring groove.
 

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Discussion Starter #15
Does the pistons have Vertical Gas Ports in them? I haven't heard the term Jetted Rings before...

I copied this since I think we are talking about the same thing....
Taken from Wiseco's FAQ:

Q. What are gas ports and when should they be used?

A. Vertical gas ports are primarily used in drag race applications. Lateral gas ports are more often used in circle-track and road-race applications where carbon build up can occur. When gas ports are used, pressure is directed to build up behind the compression ring and seal it against the cylinder wall. This helps prevent ring flutter and extends the power curve upward in the RPM range. Vertical gas ports have the holes drilled from the deck of the piston into the top ring groove and behind the ring. Lateral gas ports are drilled through the bottom side of the top land and extend to the back wall of the ring groove.
Sorry, brain fart on my part. Vertical Gas Ported!
 

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Discussion Starter #17
A few of my buddies have done with on high boosted cars. Has worked great!
With that and the tougher rings I was thinking it may feel a little rough. It actually feels smoother than when it was stock. I'm like this setup. Now I have to see if it will hold up at the track.:lol:
 

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They are all very happy. Seems to hold higher boost SO much better. None of them have rebuilt their engines "yet".
 

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Discussion Starter #19
They are all very happy. Seems to hold higher boost SO much better. None of them have rebuilt their engines "yet".
The operative word!

So, took the measurements for the cage today. Should be done next week. I'm going to drive it a few weeks with the heavy oil in it to make absolutely sure the rings have seated. Then it is back on the dyno.
 
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