Need help with LS1/4L60e tune, bad idle

[LS-SWAPPER]

I know this has been covered in may different ways, and I've searched around but haven't found a fix. First off I need to say that I am still a novice especially when it comes to tuning with major engine changes. We are trying to get a friends LS1/4L60e going in his classic car (in other words this is a swap). It has a decent sized cam, headers and cold air intake. The MAF, throttle body and engine displacement are still stock. I have it running OK on the highway and during WOT but the idle is embarrassing. It starts up just fine and as long as I let it warm up completely it will drive, but if the ect is below 180*F it will die when put into gear. Once it is warmed up it will still stumble pretty dramatically when put into gear but it will recover. Even when its warmed up the idle still hunts for steady state for a while and then finally it will stick at 850 rpms like I have it set to do at the moment.

Like I said, this is my first time trying to tune a vehicle with a larger cam and I am pretty sure its what's causing my trouble. Can someone please take a look at the tune in progress that I have? Also attached is a datalog and the cam specs. I'm sure its an easy fix for you guys. Thanks!

[bimbleuk]

That cam looks like the one I've just installed. I've been using the tune in the first post below as a base for my tuning.

http://forum.efilive.com/showthread....ips-amp-Tricks

It's for a manual car so I can't help with specifc changes for an auto however that tune idled OK on my LS1 with the 222/224 cam. After doing a few CALC.VET runs to dial in the MAF and VE tables it's pretty good now. You may not have enough base air flow at idle at the mo. On my TB (80mm Edelbrock) I adjusted the idle bypass screw so that the Idle Control Valve sits at 50 steps at idle. I've seen 80 steps mentioned in the tutorials but it appears to work better around 50 steps on my car anyway.

Only annoying thing on my car now is a surging between 2-3% Throttle angle at low speeds which I need to work on but may not be helped by the slop in my transmission.

[gmperformancecentre]

give this a try

[EagleMark]

I know this has been covered in may different ways, and I've searched around but haven't found a fix. First off I need to say that I am still a novice especially when it comes to tuning with major engine changes. We are trying to get a friends LS1/4L60e going in his classic car (in other words this is a swap). It has a decent sized cam, headers and cold air intake. The MAF, throttle body and engine displacement are still stock. I have it running OK on the highway and during WOT but the idle is embarrassing. It starts up just fine and as long as I let it warm up completely it will drive, but if the ect is below 180*F it will die when put into gear. Once it is warmed up it will still stumble pretty dramatically when put into gear but it will recover. Even when its warmed up the idle still hunts for steady state for a while and then finally it will stick at 850 rpms like I have it set to do at the moment.

Like I said, this is my first time trying to tune a vehicle with a larger cam and I am pretty sure its what's causing my trouble. Can someone please take a look at the tune in progress that I have? Also attached is a datalog and the cam specs. I'm sure its an easy fix for you guys. Thanks!

Something is wrong with how you adjusted your Main VE table, it's way off?

[LS-SWAPPER]

Thanks guys. Yes my VE table is off I'm sure, I was working on that when I had to quit. It's hard to tune the car when I can barely drive it around the parking lot. However, I don't think the VE is whats causing my issue but maybe I'm wrong. The reason I think that is because my idle issues are equally bad regardless of VE changes. In other words after I had started building the tune and it was still running the stock VE table, the dying when put into gear issue was just as bad as it is now. None of the VE changes I have made seem to affect this problem. One of the tables somewhere is changing the parameters of the tune when it is changed from P/N to reverse/drive. There are obviously a few different files that seem to play into this but I'm a little nervous to just start arbitrarily changing stuff.

On the other hand, I'm a little embarrassed to say I don't think the Calc.VET procedure went as planned. I'm almost positive it wasn't completed properly. Is my problem stemming from that??? Like I said though regardless of whether I was using stock parameters, Calc.VET attempts, and any other VE adjustments the dying issue while changing from P/N to a gear has pretty much remained unchanged. About the only thing I can do to alter it any is by changing the idle RPM settings and that has minimal effect.

For the record bimbleuk, I feel like this car would run fine if it was a standard trans. It runs great once its out on the road, and it idles decent...until the gear selector tells the computer that the shifter has been moved. And you might be right on the base air flow at idle issue. I know some people drill the throttle plate, other adjust the screw like you mentioned. What is the best way to tackle this?

By now everyone is probably worn out from my NOOBness! Sorry, and thank you!

[joecar]

AutoVE and Calc.VET are different... the latter is a more general case of AutoMAF.

[bimbleuk]

If there is a bypass screw then use that I think that on larger cams there may not be enough adjustment so they have to drill the hole bigger. You won't need to do that with this cam.

As mentioned the VE is all over so go back to a stock values or copy the VE table from the LS1 M6 tune I referenced. That'll certainly be closer than what you have now.

I only started myself this year and it took me a few weeks to get the maps setup correctly when logging and develop a suitable driving style plus route to correct the majority of the VE in a single drive.

[minytrker]

Thanks guys. Yes my VE table is off I'm sure, I was working on that when I had to quit. It's hard to tune the car when I can barely drive it around the parking lot. However, I don't think the VE is whats causing my issue but maybe I'm wrong. The reason I think that is because my idle issues are equally bad regardless of VE changes. In other words after I had started building the tune and it was still running the stock VE table, the dying when put into gear issue was just as bad as it is now. None of the VE changes I have made seem to affect this problem. One of the tables somewhere is changing the parameters of the tune when it is changed from P/N to reverse/drive. There are obviously a few different files that seem to play into this but I'm a little nervous to just start arbitrarily changing stuff.

On the other hand, I'm a little embarrassed to say I don't think the Calc.VET procedure went as planned. I'm almost positive it wasn't completed properly. Is my problem stemming from that??? Like I said though regardless of whether I was using stock parameters, Calc.VET attempts, and any other VE adjustments the dying issue while changing from P/N to a gear has pretty much remained unchanged. About the only thing I can do to alter it any is by changing the idle RPM settings and that has minimal effect.

For the record bimbleuk, I feel like this car would run fine if it was a standard trans. It runs great once its out on the road, and it idles decent...until the gear selector tells the computer that the shifter has been moved. And you might be right on the base air flow at idle issue. I know some people drill the throttle plate, other adjust the screw like you mentioned. What is the best way to tackle this?

By now everyone is probably worn out from my NOOBness! Sorry, and thank you!

Its already been said but your VE is definitely off and could cause it to run poorly.

If there is a bypass screw then use that I think that on larger cams there may not be enough adjustment so they have to drill the hole bigger. You won't need to do that with this cam.

As mentioned the VE is all over so go back to a stock values or copy the VE table from the LS1 M6 tune I referenced. That'll certainly be closer than what you have now.

I only started myself this year and it took me a few weeks to get the maps setup correctly when logging and develop a suitable driving style plus route to correct the majority of the VE in a single drive.

99.99% of the time you should never drill a hole in a throttle body.

[jstplyn331]

I have a few issues with my new setup, I had this tuned by a local guy that did this on my swap and it ran OK, but then we found out I needed to go bigger.....:0) You know due to bad rings.

So know it is a 383 LS1 with a 4l60e and I am having a hard time ideling. I am not sure the guy that tuned it the first time was at all very good anyway, So I bought a V2 and thought I would give it a go.

Along with the motor build we also did headman header long tubes 3" exhaust. Same cam as it was big and would still work.

here is my file, but not sure what to change and or if it was even correct in the begining. any help would be much appreciated and thank you in advance.

[joecar]

More info (year/model/vehicle, any other mods, FPR...)...?

Log files...?