[Mark R]

I read the thread about the Soler Throttle Body, wherein the OP said the car's computer was basically shutting down the ability to make power with the throttle body, due to the stock tune.

I'm wondering how much power can be had by simply tuning a stock engine, or one with a throttle body, or an exhaust, or a CAI. These components don't really seem to add power, but are pretty common.

Would there be any negatives to going this route? Could a person get 50-70 HP just letting the engine realize the full potential of a basically stock set-up?

Curious minds want to know............

PS: Also, when a car is tuned, how does it still pass emissions tests?

[Chris357]

1. 50-70 peak hp? No, but I follow Pray Performance on facebook and he's been able to get tune-only cars into the 10s because there's huge amounts of torque gained by a tune in the middle parts of the RPM range. maybe 25hp peak at most?????? I'll let others that know more chime in here.

2. Emissions tests these days simply check the computer for completed readiness tests and pending codes. As long as the tune isn't disturbing those processes or throwing codes you're good. Even a tailpipe test would pass provided that the tune doesn't cause an overly rich idle or some such. A tune is going to void your warranty though.

[PROMETHEUS]

You are not going to get the full potential of a ported TB or CAI, without a tune. Those mods do not require a tune and should not cause a CEL.
Tunes generally do not cause an emission problem. With a ported TB, CAI, I would expect an increase in HP. But it certainly isn't going to give you drastic power.
The negative issues associated to a tune is the almost certain loss of your powertrain warranty from GM. So my advise to anyone is if you can afford the loss of your powertrain "if you have one", than tuning is a positive. However, finding that guy or shop that knows what they are doing when it comes to tuning....is a must for any car owner thinking about it. Do you due diligence, do your research, ask other owners, check reviews. Don't be afraid to ask questions of that guy or shop! If they cant/wont be upfront and open......walk away, no better yet, run away!
Because someone who doesn't know what they are doing, can do more harm than good!
GM, like most car manufacturer's, I suspect tune cars on the conservative side, for two reasons,
They don't want to deal with a large number of warranty issues and
government regulations on mileage, emissions, etc.
Is there hidden HP in these cars which can be accessed with the addition of simple mods and a tune. IMHO, absolutely!
I am sure you will get a fair share of opinions on this matter by others!

[Mark R]

Originally Posted by PROMETHEUS

You are not going to get the full potential of a ported TB or CAI, without a tune. Those mods do not require a tune and should not cause a CEL.
Tunes generally do not cause an emission problem. With a ported TB, CAI, I would expect an increase in HP. But it certainly isn't going to give you drastic power.
The negative issues associated to a tune is the almost certain loss of your powertrain warranty from GM. So my advise to anyone is if you can afford the loss of your powertrain "if you have one", than tuning is a positive. However, finding that guy or shop that knows what they are doing when it comes to tuning....is a must for any car owner thinking about it. Do you due diligence, do your research, ask other owners, check reviews. Don't be afraid to ask questions of that guy or shop! If they cant/wont be upfront and open......walk away, no better yet, run away!
Because someone who doesn't know what they are doing, can do more harm than good!
GM, like most car manufacturer's, I suspect tune cars on the conservative side, for two reasons,
They don't want to deal with a large number of warranty issues and
government regulations on mileage, emissions, etc.
Is there hidden HP in these cars which can be accessed with the addition of simple mods and a tune. IMHO, absolutely!
I am sure you will get a fair share of opinions on this matter by others!

I'm not going to do it because I have a warranty, and I have spent all the money I want to on this car for now. I just thought if someone did it, tune only, that it would be interesting to find out, for when my warranty does expire.

[ssmofo]

Ted Jannetty, what do you think about this question?

[SFV1LE]

If I was prepared to lose my warranty, I wouldn't waste time with a tune on only a CAI and PTB, it seems like a low return on the no-warranty risk being taken.

I'd do go 1 of 3 routes adding to my existing PTB and RF CAI:

1. Modest pulley to keep heat down (prefer belt in black so no visual signs of modification), ported SC, headers and green cats, tune
2. Everything above plus E85
3. Everything above but substitute ported SC for Magnuson 2650

[ProjectZL1]

Originally Posted by Chris357

1. 50-70 peak hp? No, but I follow Pray Performance on facebook and he's been able to get tune-only cars into the 10s because there's huge amounts of torque gained by a tune in the middle parts of the RPM range. maybe 25hp peak at most?????? I'll let others that know more chime in here.

Check this out, we did testing on TB's and saw that the stock tune closes the throttle body partially starting somewhere close to 3000 - 3500 rpm and gets down to 68% closed on even the stock TB to about 5000 rpm where it lets it go back to 100% open. I assume with a tune alone you could pick up 75 hp in that RPM range if you can stop the TB from partiality closing. I would not worry too much about peak gains at the top of the RPM range when you only spend a second or two. You want the power increase from 3000 - 3500 to 5000 where you spend a lot of time while driving.
.

[Mark R]

Originally Posted by ProjectZL1

Check this out, we did testing on TB's and saw that the stock tune closes the throttle body partially starting somewhere close to 3000 - 3500 rpm and gets down to 68% closed on even the stock TB to about 5000 rpm where it lets it go back to 100% open. I assume with a tune alone you could pick up 75 hp in that RPM range if you can stop the TB from partiality closing. I would not worry too much about peak gains at the top of the RPM range when you only spend a second or two. You want the power increase from 3000 - 3500 to 5000 where you spend a lot of time while driving.
.

Yours was the exact thread I was thinking about when I posed the question.

[CW3SF]

The emissions question depends on where you live. If you live in California or certain counties of Colorado any tune will absolutely cause an immediate fail on the emissions check.

They check for a tune, not just if you have codes. And they will fail you for it.

[JasonSB]

Originally Posted by ProjectZL1

Check this out, we did testing on TB's and saw that the stock tune closes the throttle body partially starting somewhere close to 3000 - 3500 rpm and gets down to 68% closed on even the stock TB to about 5000 rpm where it lets it go back to 100% open. I assume with a tune alone you could pick up 75 hp in that RPM range if you can stop the TB from partiality closing. I would not worry too much about peak gains at the top of the RPM range when you only spend a second or two. You want the power increase from 3000 - 3500 to 5000 where you spend a lot of time while driving.
.

If the throttle is closing then the odds are there are torque management issues. With an intake and ported TB on the stock tune I had no issues with the TB closing and the AFR was fine. I didn’t dyno it so not sure about HP gains but the stock tune was not an issue.
I would be surprised if there are any HP gains from tuning those mods. Maybe a few HP.

[JasonSB]

Originally Posted by CW3SF

The emissions question depends on where you live. If you live in California or certain counties of Colorado any tune will absolutely cause an immediate fail on the emissions check.

They check for a tune, not just if you have codes. And they will fail you for it.

How would they know if the car has been tuned? I haven’t looked in HP Tuners but does it say the stock map has been modified? Seems strange that they would be able to figure that out.

[SJFGTO]

A professional dyno and street tune might net you 15-20 more HP under the usable portion of the curve, maybe an overall gain of 20. I’d wait until I added long tubes and a pulley.

[Junkyardspecial]

I was tuned on Rotofab intake, and Kooks Long tube cat less headers with a corsa extreme exhaust.

I only gained 7whp on the top but over 80whp in the lower part of the power band.

[radz28]

While I thought that test seemed as scientific as one could reasonably be, I later wondered if heat soak was also taken into account. These things start KILLING power after a few runs due to heat soak. I don't recall if IATs were compared or monitored, but I wouldn't claim to know either way. I know heat soak is an issue though.

CSP did a test a while ago. They started with a stock car. They dyno'd in stock and PA temperatures around 30-40 degrees. Later, they ported the blower, then tuned, and followed up with more tests. As far as the tuning for the blower, they only picked up about 10-RWHP (something like that). Surely, the blower leaned the car out some, but tuning in that instance wasn't worth too much - peak-to-peak. After tuning the mid-range (I think there may have been some PM adjustments - I wouldn't claim to know that either though), the throttle stopped closing (like was seen in this video), and torque was back up (even though it didn't really effect power).

IMO - a tune might be worth maximizing everything you've done, but not necessary for a TB or CAI. You'll surely get a little more power, but it's not cheap. Bettering results, at least for A10s, would be tranny tuning by someone like PRAY or something. I totally agree with warranty concerns, as mentioned above. And above all else, if you decide to tune, make sure the person knows WTF they're doing...