What mods did you do that made no difference or you regret

[crazydave]

Originally Posted by Viczl1

I'm shooting for 600-625whp. I started the thread to gain information on what not to have to do over. I'm famous for that haha. I don't mind modding in stages, in fact it's more fun that way so I can stay married.

The issue is that once you do anything that requires a tune, you will have to pay AGAIN to get it retuned.

I would suggest:

Stage 1: Rotofab CAI and ATI balance with 5% OD. Plus I would add a coolant reservoir at this time which will double system capacity and make purging air from the system a breeze. This alone netted me about .3 in the 1/4 mile. No tune needed. You might be happy with just these mods.

Stage 2:Upping the lower to a 9.1" (18% OD) and adding ID 850 injectors and headers. You can go up to a 9.5" but that's close to the limit on the stock FP (I did and didn't have any fuel problems). If you run the 9.5" you will also need a relocation bracket for the lower idler pulley. I would also at this stage recommend a larger front heat exchanger to cool the now much hotter charge. I was right at the 600rwhp mark with a conservative street tune.

[ZMEnow]

Originally Posted by Can'tHave2MuchHP

This is straight BS. Headers drop the boost pressure, but you don't lose that HP, you end up gaining RWHP and RWTQ with Headers. Boost = Restriction, and it is not always good. The supercharger is still putting that same amount of air into the engine, only thing that changed was the pressure of which it was under.

So do Headers if you want more flow (HP and TQ) and sound.

OP, I'd recommend waiting until you go in for real or don't mod. I'm the guy that's choosing to not mod because I know I'll be moving on shortly. If that is you, then don't mod. But if you plan to keep her then save up a few thousand do real mods right off the bat. If I could choose I'd do...

-9.1" Lower Pulley
-BTR 3 Cam
-ID1300s
-Cold air intake
-Headers
-Heat Exchanger
-Vmax ported throttle body
-Tune and misc necessary parts.
-R888 Tires all around

And drive it and enjoy it.

I experienced the same as JP has noted.. Friends that have done just long tubes and no cat's through Lingenfelter's have dyno'd 475rwhp with M6 with the tubes and modest tune. I have yet to see a stock M6 z dyno anything but 505 -519 stock.

http://performance-dyno.com/blog/2013-camaro-zl1-stage-2

Hey everyone, this is josh pearl (JP) with an update on my 2013 Camaro ZL1. After a long wait I have finally completed "Stage 2" of my build which includes Kooks long tube headers (ceramic coated with 2" primaries), Kooks 3" to 2.5" off-road pipes, Injector Dynamics 850cc injectors, Kenne Bell Boost-A-Pump, Metco 10" lower pulley, AFCO Racing heat exchanger (with dual fans), and NGK TR7ix spark plugs.
​
I'll provide some thoughts on the mods and results below. As usual, each dyno sheet is showing runs from the same day with equivalent coolant, oil, and intake temperatures. This will provide true before and after results.

Step 1 - Headers, Off-Road Pipes, and Plugs:

​The dyno sheet below shows some VERY interesting results from my Kooks header installation... no power gains! This was a bit disapointing at first, but simply proves that the factory manifolds and catalytic converters provide sufficient flow for ~600rwhp. This behavior is not uncommon on supercharged vehicles; we see it with Mustang Cobras and GT500s too. Blown motors do not experience the same benefits from improved exhaust scavenging as naturally aspirated vehicles because the supercharger is pushing the air through the motor. The exhaust simply needs to provide a hole big enough to let the air out.

​Step 2 - Tuning for the Headers:

​Though the headers did not realize an increase in power, they did provide a reduction of back pressure as seen in the slightly lower boost levels. This provided an opportunity to adjust the tune to gain some power as seen in the chart below. After the tune there was an increase of 15whp and 15wtq above 4,000rpm. These are certianly nice gains, but the cost of this power was quite high: $1,200 + install time + tune session. At this point in the build, my recommendation to ZL1 and CTS-V customers who have done my previous "Stage 1" mods would be to not invest in long tube headers unless further mods are planned...

​Step 3 - Injectors:

My experience with many different injectors led me to Injector Dynamics I850s for the ZL1. These are not the cheapest injectors available, but the quality and precision of the injectors and injector data is second to none. I often recommend these injectors to customers, because injector data is something a tuner cannot make-up or backwards engineer. There are multiple vendors who provide good quality injectors with data, but many who do not. The dyno graph below shows two pulls which are nearly identical... this is because the only change to the car was the installation of the ID850s and the only change to the tune was the injector data provided by Injector Dynamics for HPTuners. You can see the variance between the pulls is within the range of "run-to-run variance." Most low cost injectors would be unable to match this level of precision! This is why many tuners will not tune a vehicle without proper injector data.

Step 4 - 10" Lower Pulley + Tuning

My final modification for "Stage 2" of the ZL1 build was to install a 10" lower pulley. I previously installed the Innovators West Harmonic Balancer with Metco 8.6" lower pulley which provides ~2lbs extra boost over stock. The 10" lower pulley provides ~5lbs extra boost over stock. This large pulley does require an idler relocation bracket, but the installation is very straight forward and reuses the factory idlers. The tune was updated to compensate for the additional boost.

Note: the before and after pulls were not done on the same day although the operating temps were monitored to provide as much consistency as possible. Mid way through the installation my wife called with a "slight emergency." Long story short we ended up at the hospital for the birth of our first child. Some distractions are quite worthwhile

As you can see in the dyno sheet below, the gains from this pulley were very large: +48whp, +86wtq, and +4lbs boost. The torque increase was much higher than expected and the horsepower increase is on target. Taking a look at the dyno sheet you can see the boost spike above 5,000rpm. This boost spike and the ramp-down in the torque curve is indicative of a restriction in the system, which can be cured with a blower swap and/or upgraded cam

Conclusion:

All in all I would consider the "Stage 2" modifications a great success. The header swap did not offer much increase with the "Stage 1" modifications, but I feel the reduction in back pressure was a stepping stone for the big gains seen with the 10" lower pulley. In other words, I would not want the pulley without the long tubes and the long tubes are not a worthwhile investment without a large pulley.
​
With the installation of a lower pulley, idler bracket, belt, cold air intake, injectors, long tube headers, off road pipes, boost-a-pump, heat exchanger, and of course Performance Dyno tuning the ZL1 is up 150whp and 183wtq over stock!!

[d454brisson]

I did the Jannetty 75 hp kit then basically right into the 125 upgrade. They only thing I couldn't reuse was the pulley which i sold on ebay. Since i sourced some parts elsewhere I paid extra for the retune.

Sold my stock injectors for 200$ and stock balancer and bolt for 100$ so recover a couple bucks. Every little bit helps.

Honestly I would recommend going straight to the 125 version above if you can swing the parts out of the box.

If on a budget or building in stages go step by step and resell some parts.

Each step was easy and doable in just a few hours in the garage.

[crazydave]

Originally Posted by ZMEnow

Would have skipped headers and high flow cats between 10% JRE setup and 18% or 75RWHP and 125RWHP. The loss of boost made the car a dog.

You must need a new tune. This post is very misleading and not what a properly tuned car behaves like with headers. My car with a 5% and headers was far from a dog.

Your post above states a good deal of factual information such as:

Headers drop boost but add HP=True

The gains from headers are not as good as on a N/A engine=True

Is it worth the $1200, for a 15-30HP average gain(depending on mods) on a 500RW HP car? For some people it is. Headers are a good foundation piece that allows you to support more modifications in the future and to get a bit more out of them. If someone plans to ONLY do CAI and headers, then I would advise against headers as there are better HP/$ mods that you can do. Pretty soon, once you start modding you have to look to every avenue to gain additional HP. Headers do also help with your under hood temps a little bit if you get them ceramic coated vs the stock manifolds.

Headers kind of suck in states with reoccurring emissions inspections, so keep that in mind when you make your decision.

Also, don't forget to also go to the CTS-V forums for additional info. They had a few years head start on us with the LSA.

[Harley01]

Originally Posted by owhite3003

Like what was said above, wish I would have went 1300 injectors instead of the 850s.

+1!!

[Crash76]

If you dont plan on ever doing E85 then 850s are perfect...

Of course now i want to run e85...

Ill probably ditch my BAP and 850s soon... whole 500mi on them haha... such as life

[STUNNAH]

Originally Posted by Viczl1

Trying to get a feel for what not to do. In the past I've modded everything I owned and a lot of times just wasted time and money. I'm trying to get a feel for what not to do.

Most of the Stage 1 kits will get you close to 600rwhp at a reasonable price $2,500.00 installed...Like the other's have said knowing what your goals are and what you intend to do with the car is a major factor in getting solid recommendations...If you can't answer those questions it would be best to enjoy the car stock for awhile...While your making up your mine do the fuse pull to leave your cutouts open, fuse is in the trunk F8 I believe and you can add a CAI without a tune about $400.00...No lost money...

[deeds]

Same here as most. I should have went right to ID 1300's and a fuel pump instead of 850's and a BAP.

I was thinking the same as you were when I first got my car 625 RWHP is where I'll stop modding. But me being myself now my goal is 750RWHP+ and after that Im sure it will be 800hp then 900hp and so on.

[Viczl1]

Lots of great information here so far. This thread is a goldmine for someone starting out like myself.

[Nor Cal ZL1]

Originally Posted by crazydave

You must need a new tune. This post is very misleading and not what a properly tuned car behaves like with headers. My car with a 5% and headers was far from a dog.

Your post above states a good deal of factual information such as:

Headers drop boost but add HP=True

The gains from headers are not as good as on a N/A engine=True

Is it worth the $1200, for a 15-30HP average gain(depending on mods) on a 500RW HP car? For some people it is. Headers are a good foundation piece that allows you to support more modifications in the future and to get a bit more out of them. If someone plans to ONLY do CAI and headers, then I would advise against headers as there are better HP/$ mods that you can do. Pretty soon, once you start modding you have to look to every avenue to gain additional HP. Headers do also help with your under hood temps a little bit if you get them ceramic coated vs the stock manifolds.

Headers kind of suck in states with reoccurring emissions inspections, so keep that in mind when you make your decision.

Also, don't forget to also go to the CTS-V forums for additional info. They had a few years head start on us with the LSA.

Exactly. If you did headers, cam and ported heads without pulley changes, your going to dump a lot of boost. Each one decreases the restriction and lowers the boost numbers. It all goes back to tuning. Lower the boost, make it up with timing etc.

Headers are expensive if your only going to add those, and a CAI. Certainly pulleys are the less expensive route. Its a mod that is of better benefit when combined with a goal of other parts.

[evonschu]

Think carefully if you decide to get catless headers. They sound badass, but they will have the smell of unburnt gas when you're idling. This can get annoying and people in the backseat might get "gassed out" aka Mom. Although its a whole other discussion whether having cats on past a certain HP will just blow them out. I know a few people with the JDP 850 package with cats and have no issues. Just my 2 cents.

[GONMAD510]

Originally Posted by evonschu

Think carefully if you decide to get catless headers. They sound badass, but they will have the smell of unburnt gas when you're idling. This can get annoying and people in the backseat might get "gassed out" aka Mom. Although its a whole other discussion whether having cats on past a certain HP will just blow them out. I know a few people with the JDP 850 package with cats and have no issues. Just my 2 cents.

One thing really stood out in your comment. You can get people in your backseat. My car is basically a 2 seater. .

[Stephen12ZL1]

JBA high flow cats were useless and failed fairly quickly at the road course. I should have skipped that step and gone with headers immediately.

[918Stealth2SS]

I would of had the regret of going with 850's but talked with Ted today....for my total complete goal since I know once I keep growing in power, I will always want more. So I'm going to do 1300's and E-85 dual right out of the gate. Fuel will be step 1 on my way towards AGP TT.