njm12333

I have an 01 z28 t56. SLP intake, ported and polished stock tb, ls6 intake, long tube headers with true dual 3 inch exhaust with small mufflers. Would it be worth it to get a professional tune done? There is a very reputable tuner who does dyno tunes nearby. Would it be worth it and what could I get out of the car with a tune?

the_merv

iTrader: (88)

If they are a good tuner you'll notice a difference. LT Headers need a tune to get dialed in right.

Y2K_Frenzy

10’ish horsepower maybe?

RPM WS6

iTrader: (3)

If you are done with modifications, at least for the foreseeable future, then I would definitely suggest getting a tune to get the most out of the setup. If you plan other mods in the foreseeable future, I would just wait and get it all done at once.

the_merv

iTrader: (88)

20+ wheel easily with them mods if it's still a stock tune in the PCM. If you saw how under-tuned these cars are from the factory you'd know what I mean.

RevGTO

iTrader: (12)

Yep - 20+ for sure plus so much more torque in the mid-range - power under the curve.

Another option is to buy a tuning suite and learn to do it yourself. I did that years ago, but back then, there was a repository of tunes online that you could match with your mods to give you a baseline. It's a steeper climb these days.

Nonetheless, it gives you the opportunity to continuously modify your tune till you get it where YOU want it, rather than having to be satisfied with someone else's interpretation of your goals.

Y2K_Frenzy

20+ from the tune alone? Or are y’all saying the headers plus the tune equal more than twenty? Example- headers were good for fifteen and the tune “squeezed” another five out of it. When I first got Camaro I was googling around looking at dynos for long tubes on stock motors & it seems likes most stock were gaining around 15’ish horsepower. I remember it being on the lower side to where the “bang for buck meter” wasn’t that good. Cars with cams saw a bigger gain though.

the_merv

iTrader: (88)

You literally quoted my post that answered what you just asked.

Y2K_Frenzy

The OP asked how much power from THE TUNE and you said, “With those mods 20.” The way you worded it makes it sound like he’ll get an additional 20 horsepower (from the tune) on top of the 15 or whatever gain the headers gave. So if he got a tune is he getting an additional 20 horsepower from the tune? No correct? It’ll be twenty or so “all in.” Arbitrary numbers- 15 from the headers and the tune gives five more. So with a $500 tune (arbitrary) he’ll gain an aditional five to ten horsepower.

the_merv

iTrader: (88)

You're way over analyzing this.

His mods with the proper tune to dial it all in I see at minimum 20+whp gain. That's everything above combined in his car if it's still on a factory tune.

I don't have exact numbers for each mod, just making that call based on stuff I've seen and done.

RPM WS6

iTrader: (3)

The factory tune leads to a rich condition at WOT, and this only gets worse (for most examples) when you add LT headers. Just cleaning up the fuel trims and adjusting timing with a completely stock car will usually show gains of 7-12rwhp depending on how aggressive you get, and those potential gains will increase as you add modifications that cause fuel trims to be even more elevated than stock. So, yes, it's certainly possible to gain 15-20rwhp from just the tune alone if you're coming from a 100% stock tune plus all of the modifications listed above.

the_merv

iTrader: (88)

Hence why the tuning is the last step. Get everything in there and then dial it all in.

Y2K_Frenzy

I was looking at it from a monetary perspective just incase he doesn’t have self-tuning capabilities. He asked is it “worth it” and I’m assuming the “it” is money. My initial guess of ten horsepower was what he would gain from tuning. That’s just a guess of course based off of reading a butt-load of long tube header dyno threads. It looked like most stock cam guys were gaininng 15-25 horsepower (some less) from headers and a tune. So I deducted that the headers are probably where the bigger chunk of extra power came from and the tune was able to squeeze out a little more. I was guessing it was the headers because if the A/F ratio was all that bad after LT’s then there wouldn’t be reports of guys going a little faster down the 1/4 mile un-tuned after switching to LT’s. If a tune is worth it or not kind of depends on how much the tune costs and if one is willing to pay X amount for a hair more power.
Long story short I think he was asking how much power is he leaving on the table without a tune. I bet not a whole bunch but some.

99 Black Bird T/A

iTrader: (4)

Yes, the tune is worth it on a bolt on car as the last step.

My stock 02 Z28, A4 w/2.73's dyno'd 280 whp.

Tuned with FTP 98mm lid, 85mm MAF, WARR 92 mm TB, 90mm LPE snout LS6 intake, 1 7/8 long tube headers, Kook's 3 inch Y pipe, SLP Dual/Dual catback, new plugs, new wires made 326 whp

46 whp gain peak to peak plus lots of area under the curves. Well worth it.

jond99

iTrader: (1)

Could always
get a handheld tuner. That’s what I did with a bolt-on only modded engine. Very noticeable gains. Plus it acts as a code reader for future use.

G Atsma

Handhelds aren't real tuners....

jond99

iTrader: (1)

Searched around and found this:

https://ls1tech.com/forums/dynamomet...o-results.html

the_merv

iTrader: (88)

When you dial in the proper airflow, timing, and get the fuel right, these things come alive. If you ever saw a stock tune compared to a good one, it's night and day. I said 20+whp to be on the conservative side with them mods. Bone stock cars tune only can get that gain if you tune it up good. LS Engines have a sweet spot with the timing, you don't need to go to a couple degrees before knock like other stuff.

I would not drive around with a car not dialed in correctly. It'll be rich, lean, and run like ****.

RPM WS6

iTrader: (3)

I tend to disagree with this part of the third post in that thread:

~265rwhp would be pretty low on a DynoJet (unless newer DynoJets are more like a Mustang Dyno?) for a stock '01+ A4 LS1 F-body. Anything below 280-285 would indicate, to me, something (engine, transmission, fuel system, etc.) that is hurt, worn, or in need of maintenance. All things being proper, 280-300 would be more accurate for an A4 example.