Finally bought my first LS1 to make the jump from LT1. Now, the 99 SS vert, is sitting and looking pretty in my garage.

By the way, since my car is bone stock, should I get it tuned? What are the advantages of getting it tuned?

Although eventually I do want more power, I do not really need them right now.

Please advise. Thanks.

 

Though you could likely pick up a small bit of power even on a stock car, personally I would not get a tune until I did some mods.

 

Personally I wouldn't get a tune on a bone stock car. You may pick up a couple ponies but nothing to justify the 300-500 for a dyno tune. The stock PCM is actually pretty decent. I would minimum get a set of headers, intake and exhaust before a tune. Even then with the minor bold ons the stock pcm can do an ok job of keeping up and a tune may not pick up a whole lot. You will be pleasantly surprised how much your car will wake up with a set of headers($300-$400), Lid(~$100) and a LS6 intake(~$300). If you decide to do a cam then I would definately say to get a tune even though a stock PCM can handle a small one.

 

I agree with the above posts. Tuning a stock car can yield some gains, typically between 10-15 rwhp, but it would be more beneficial to stick some exhaust on the car first. The cars respond very well to long tube headers and free flowing exhaust. I personally feel that those modifications are more satisfying then just a tune, espeically for the money.

 

I just got some headers this weekend - I'm really happy I got them, the car not only sounds way better but it runs stronger too. I say headers over the tune.

 

Headers and a lid then tune the bad boy!

 

a4 or m6?

 

Id do your bolt ons first then a tune.

 

Bringing an old thread back!

Update:

Well, right around last month, I did a dyno and my car pulled 306rwhp but the AFR ratio was at 14.1 from 3500 to 5000rpm. Now after the dyno, i changed the plugs and wires, and it turns out my plugs were shot to hell, some of them have a gap at .070 or higher. After the plug were changed, the car runs a lot smoother and idle better. So, right now, I really need to make sure that my afr is good, therefore I think a tune is necessary. Current mods: SLP lid and SLP dual/dual.

I am worried driving the car at 14.1 afr, so i am gonna bite the bullet and get a tune to make sure my engine is healthy. I am not planning to add anymore power mods, just suspension mods in the foreseeable future.

Another question: If i get a tune now, and I add more mods in the future and I go back to my original tuner, do I still have to pay full price, assuming I do not do any internal mods? Generally speaking of course.

What do you guys think?

 

You may have better luck with these questions in the PCM Diagnostics and tuning section.

 

Thanks, I will post there.

 

If you have a bone stock car that's running an overly lean AFR, your problem is NOT the tune. Understand, these cars were tuned to run rich at WOT from the factory. If you have not modified any engine related parts on this car, then the problem is NOT your tune. At this point, for that condition, a tune would only be masking your actual problem. Actually, a tune may not even be able to mask it, if the issue is weak injectors or pump, etc.

 

Thanks.

I checked the fuel pressure at the rail and I am getting 60psi consistent throughout all RPMs, which lead me to believe that my fuel pump is ok. The injectors though, i have no idea on how to check those.

Another objective with the tune is to make sure that my car really is lean, and not because of any mechanical problems. I already spoke to my tuner and he said that some of these cars runs lean from the factory although most are setup to run rich.

Also, if i have a weak injectors, can I assume that my MPG will increase since the injectors are not spraying enough fuel?

Lastly, any advice on how to check if my car is running lean aside from spending $200 for a wideband sensor? Can i inspect a sparkplug or something in that nature?

Thanks for all the help.

 

Just do bolt ons and enjoy it. I miss my stock car, especially the gas milage.

 

A lid and exhaust cut out will yield the most ponies for the cheapest, if you have a ton of money to throw at it right off the bat id do long tubes, manifold,ported throttle body, and some sort of cai, possibly rear end gears.

 

If yours is an auto, and you are bent on some sort of tune id pick up a cheap *** Hypertech, used on craigslist they are like $75.00 and you can turn your shift pressures up, that makes a fairly decent difference, and makes your car funner to drive, i had my car tuned with one and it delivered the power a little better and with the shift pressures turned up it helped drivability, until i got my nitrous now im getting tuned with EFI Live.

 

If you're not planning on doing anything along the lines of a cam swap, and want a tune, you can always get a mail order tune from a reputable place like Frost. Tunes for these cars are $125 I think, and from when I talked to him a while back he said retunes within 90 days (or 30....but I think 90) were free and after that it was only $50. That way all you have to do down the road if you add any more power would be the shipping and $50 if it's outside of that time period.

Even if you're not planning on adding more power (like LT's, etc.) that $125 for an extra 10-15 hp now is worth it IMO.

 

In my experiance, LS1s were factory tuned to be on the rich side at WOT. However, your tuner may have just meant that he's seen some with factory tunes that were running lean even with a stock engine, which is entirely possible if there is some mechanical or eletrical issue with the metering or delivery of A/F mixture. But I am 100% certain that none of these cars left the showroom with an overly lean WOT tune....the OEMs like to leave a nice safety margin.

You could toss an ohm tester on your injectors, looking for out-of-spec resistance. Stock LS1 injectors should be right around 12.5 ohms when new, so anything far away from that value might suggest an issue. I'd run some injector cleaner, since you said the plugs were old/bad, chances are the injectors could use some cleaning as well. I like the SI-1 detergent from Red Line.

If you have a good OBD scanner, you can watch your front O2 values at WOT for a ballpark of your A/F. These are not as good as a wideband, but it's something you can check if you have the scanner. Leaner than .800 is very lean for a stock car, .880-.890 would be about perfect, but .900+ should be expected for a stock tune with a properly functioning stock engine, fuel and control system.

You can also look at KR (knock retard) if you have the scanner. If the A/F is as lean as you're thinking, you might be getting some detonation at higher rpms. This will show how much (if any) spark advance is being pulled. If it's 0, I wouldn't be too worried.

Check also the LTFTs (long term fuel trims). If the O2 sensors are reading an excessively lean mixture, then these LTFTs should be very elevated (like +20% or more, under all conditions). The WOT value won't do you much good though, since they lock at whatever the last observed trim cell was prior to WOT (unless they were negative, then they lock at 0). But, if you see that the PCM is strugging with excessively high LTFT under all cruise conditions, then you know that something is up with fueling (or a vacuum leak).

Lastly, yeah, you can always inspect the plugs, but that won't tell you much about WOT mixture unless you shut the engine off right after a WOT run, coast to a stop, and pull the plugs. Otherwise, what you see on the plugs will be your idle/cruise deposits. Now, if the WOT tune is super lean, you might blow the tip of the plug apart - that should be noticeable.

 

I'm not sure how correct the following is, but i was told by multiple people that LS1 cars from the factory can/will gain from a good tune due to the fact that there are some sort of torque management measures built into it.

I'm highly considering getting an acquaintance of mine do a tune via HP Tuners next season. All I have is LID and PP which I don't think that a thing.

 

Torque management isn't really an issue for you M6 guys. Auto cars can see some gains by removing/reducing it.