[NA18CamaroSS]

Modding my Camaro has been a journey. It started when I bought the car and almost immediately had it baselined to see what my starting point would be. 404 HP seems like a very respectable place to start. The very first thing I did was add a flex fuel kit and get the car tuned. It picked up 34 HP as easy as you please.
Later, I added a Pray Performance ported intake manifold, a Soler Performance ported throttle body, a RotoFab dry intake and some New Era cat delete pipes. Had it retuned. The car put down 464 HP. So far, so good. Every mod had behaved predictably and gained an appropriate amount of power.
Next I added a Pray ported MSD intake manifold. It made about the same torque and picked up about 15 peak WHP, and over 30 WHP above 6,000 RPM. Nothing unexpected. 479 WHP is quite respectable, 75 WHP over what the car had put down stock.
Here is where it gets confusing, at least for me. In January of this year I installed ARH 1 7/8" headers and full exhaust with X-pipe into the stock NPP muffler. The car made less power-significantly less. After spending a great deal of time tuning and tweaking, the car got back up to 472 WHP- 7 WHP less than it made with the stock exhaust manifolds. WTF? I still don't know why.
So, in an attempt to get the car as close to 500 RWHP before I do a cam and heads, I installed the ATI 10% under drive pulley. The car picked up 3 ft-lbs of torque and about 8 WHP on the dyno. I also feel less harmonic vibration from the engine. The ATI pulley has to be one of my favorite modifications, second only to switching to E85.I highly recommend it.
In a nutshell, the car is making 481 WHP, a 77 WHP gain from stock. The last few HP have been very hard to come by. Had I known what I know now three months ago, I would have skipped doing the headers. All numbers are SAE. I hope that my experiences will be helpful and informative for others.

[s346k]

awesome post. my power curve above 6k is a lot flatter than yours. very similar mods. mine peaks around 5900 and holds very flat to 6700.

i have

2" headers & full 3" exhaust
mamo ported msd
stock LT5 tb
rotofab cai
ethanol

i have a damper but its still holding down a table in my dining room.

cant put a relative dyno number on my car as it was tuned on a dynodynamics dyno and it reads very low. dynojet "conversion" showed ~494. dyno numbers are whatever, the car picked up 8+ mph over stock with 0 weight reduction.

[Murder6.2]

Nice write up, you’re always very informative!
So you think if you would’ve stayed with the Test pipes you’d be at 488whp?
I’ve heard Granatelli wires actually pick up about 5whp. That would be interesting to see on the dyno should put you at 485whp Atleast

[sage85z28]

I’m somewhat in the same situation as you also. So my first tune was roto fab, ported TB and ported stock IM on pump gas and it made 426, dumped in E85 and it made 449.

A couple months later I installed the 2 inch ARH headers with high flow cats, 3 inch X pipe into the stock NPP and it made 486. A hug jump and I was very pleased.

A couple more months later I was shooting for the 500 mark so I added the LT2, ported Katech 95 Tb and the ATI damper. It made more power but I have to say I was a bit disappointed with the final results.....493. It made more power which I’m happy about but all the hype about the LT2 I honestly was expecting more. Oh well it is what it is and the parts are on and the money is spent.

[NA18CamaroSS]

Originally Posted by Murder6.2

Nice write up, you’re always very informative!
So you think if you would’ve stayed with the Test pipes you’d be at 488whp?
I’ve heard Granatelli wires actually pick up about 5whp. That would be interesting to see on the dyno should put you at 485whp At least

I wish that were true. When the numbers came in after the header, install I threw on the Granatelli wires and ignition coils. I still have the stock manifolds and exhaust, but I sold the test pipes. I'm really tempted to buy another set of test pipes and throw the stock manifolds back on the car to see what happens.

[cmitchell17]

Originally Posted by sage85z28

I’m somewhat in the same situation as you also. So my first tune was roto fab, ported TB and ported stock IM on pump gas and it made 426, dumped in E85 and it made 449.

A couple months later I installed the 2 inch ARH headers with high flow cats, 3 inch X pipe into the stock NPP and it made 486. A hug jump and I was very pleased.

A couple more months later I was shooting for the 500 mark so I added the LT2, ported Katech 95 Tb and the ATI damper. It made more power but I have to say I was a bit disappointed with the final results.....493. It made more power which I’m happy about but all the hype about the LT2 I honestly was expecting more. Oh well it is what it is and the parts are on and the money is spent.

Yeah I was expecting to see a lot more increase in airflow going from a stock ported LT1 intake to a LT2 ported intake with a 95mm ported TB, but unfortunately I just didn't see much. I also have a cam and ported heads so I expected even more of an increase but it just wasn't there.

[kingwale]

Crazy but we made exactly thesame number fbo e85. I recently added ATI UD Pulley so it safe to say I’m around thesame power as you.

[laynlo15]

Those are good numbers. Congrats

[laynlo15]

I was surprised to see you lost hp on the long tubes. Mine made about 15 rwhp but it picked up 4 tenths of a second and 4 mph in the 1/4. I just added the Ported MSD and we picked up about 18 rwhp so now we are at 462. We are going back to the track tomorrow night to see what we pick up there. I hope we'll see some 10.90s or maybe a high 80.

[lt4camaro]

Originally Posted by NA18CamaroSS

Modding my Camaro has been a journey. It started when I bought the car and almost immediately had it baselined to see what my starting point would be. 404 HP seems like a very respectable place to start. The very first thing I did was add a flex fuel kit and get the car tuned. It picked up 34 HP as easy as you please.
Later, I added a Pray Performance ported intake manifold, a Soler Performance ported throttle body, a RotoFab dry intake and some New Era cat delete pipes. Had it retuned. The car put down 464 HP. So far, so good. Every mod had behaved predictably and gained an appropriate amount of power.
Next I added a Pray ported MSD intake manifold. It made about the same torque and picked up about 15 peak WHP, and over 30 WHP above 6,000 RPM. Nothing unexpected. 479 WHP is quite respectable, 75 WHP over what the car had put down stock.
Here is where it gets confusing, at least for me. In January of this year I installed ARH 1 7/8" headers and full exhaust with X-pipe into the stock NPP muffler. The car made less power-significantly less. After spending a great deal of time tuning and tweaking, the car got back up to 472 WHP- 7 WHP less than it made with the stock exhaust manifolds. WTF? I still don't know why.
So, in an attempt to get the car as close to 500 RWHP before I do a cam and heads, I installed the ATI 10% under drive pulley. The car picked up 3 ft-lbs of torque and about 8 WHP on the dyno. I also feel less harmonic vibration from the engine. The ATI pulley has to be one of my favorite modifications, second only to switching to E85.I highly recommend it.
In a nutshell, the car is making 481 WHP, a 77 WHP gain from stock. The last few HP have been very hard to come by. Had I known what I know now three months ago, I would have skipped doing the headers. All numbers are SAE. I hope that my experiences will be helpful and informative for others.

Can you tell me how easy / hard it was to replace the OE balancer with the ATI 10 % underdrive? what belt issues did you encounter? how did the stretch fit a/c belt go back on? was it to loose requiring a smaller diameter belt?

[17camaroSS]

Originally Posted by lt4camaro

Can you tell me how easy / hard it was to replace the OE balancer with the ATI 10 % underdrive? what belt issues did you encounter? how did the stretch fit a/c belt go back on? was it to loose requiring a smaller diameter belt?

I’m stilling running the factory a/c belt with my ATI

[lt4camaro]

Originally Posted by 17camaroSS

I’m stilling running the factory a/c belt with my ATI

OK, great to hear. Was replacing the balancer a easy job for you? What problems did you encounter? and you did use the 10 % underdrive unit correct? Just wondering if the ATI unit creates a 10% underdrive , how do the belts still fit?

[BlackbeastSS2]

Originally Posted by lt4camaro

OK, great to hear. Was replacing the balancer a easy job for you? What problems did you encounter? and you did use the 10 % underdrive unit correct? Just wondering if the ATI unit creates a 10% underdrive , how do the belts still fit?

Like most jobs you need the right tools.

“Harmonic dampers are typically press-fit and next-to-impossible to properly remove and install without the right tools.”

Here’s a good read to understand what you will encounter if you try it yourself.

https://www.onallcylinders.com/2020/...e-right-tools/

[17camaroSS]

Originally Posted by lt4camaro

OK, great to hear. Was replacing the balancer a easy job for you? What problems did you encounter? and you did use the 10 % underdrive unit correct? Just wondering if the ATI unit creates a 10% underdrive , how do the belts still fit?

It wasn’t too bad. But I’ve also got an uncle that runs a machine shop and warned me before to check and make sure it didn’t need honed before install like the instructions mentioned, and I’ve also got the ATI dampener puller/install kit which makes thing a pretty smooth. Ya, it’s a 10% unit.