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Discussion Starter · #1 ·
After nearly 2 years of accumulating parts, 1 year of working on it (slow work last winter), and a few hiccups, I finally got everything sorted on my car. Did a few rounds of street tuning, then made it to the dyno a couple weeks ago. I'm quite pleased with the results. :)

The process to get here was much more involved than just the LSA. Redid the fuel system (now CTS-V bucket, AEM 340 pumps, Vaporworx controller) and had the rear subframe out of the car for paint, all new bushings, all new arms including SS aluminum upper control arms, BMR trailing arms and toe rods, and BMR sway bar. Oh, and finally adding the rear brembos and stainless brake lines.

The good bit:
After a bit of initial WOT tuning work, the car made 580hp on 93 (with no ice in the trunk tank and a conservative tune since I never plan to race the car on 93). I then added 10 gallons of E85, bringing the mix in the tank to about 55% ethanol. My tuner was hoping for about 70%, but didn't have enough E85 with me. With E55 mix, the car made 648hp. We then added some ice to the trunk tank, and the final pull was 676hp! My goal was 650-700, so it's right there. It's a completely stock LSA other than the pulley and a reinforced brick. No porting yet. Made 13-13.5 psi of boost.

Afterwards, my tuner (Tim Haines) said he's pretty sure it will crack 700hp with 70+% ethanol content, which luckily I have enough fuel pump and injector for.

Most of my major mods are listed in my signature. If anyone has specific questions, please ask away.

Vehicle Hood Car Motor vehicle Automotive design


Tire Car Wheel Vehicle Automotive tire


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Trying to post video of it. Hopefully can figure it out in a following post.
 

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Discussion Starter · #2 ·
I think I got it.

 

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Very nice! Install looks super clean too. I'm not sure more E will get you to 700+ (it might) as most of the benefits of E85 are achieved at @ 50%, then diminished returns after that. What cam are you running? Any plans to port the blower in the future? Meth?
BTW, I love seeing threads like this. We need way more of them. One more, "Which cat back should I put on my V6?" and I'm going to lose my mind.
 

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Discussion Starter · #4 ·
Very nice! Install looks super clean too. I'm not sure more E will get you to 700+ (it might) as most of the benefits of E85 are achieved at @ 50%, then diminished returns after that. What cam are you running? Any plans to port the blower in the future? Meth?
BTW, I love seeing threads like this. We need way more of them. One more, "Which cat back should I put on my V6?" and I'm going to lose my mind.
Yeah, we'll see what it does on more E85. The last run (even though it had some ice in it) was also IAT of 72F at start of run, and 100F at end of run. So combo of more E and colder temps, I think it will do it.

The cam is Blue Line Performance PDS cam. 219/239 .626/.630 115. I do plan to eventually port the blower and/or do a bigger lower. Meth would come after that. Of course, all of that is after enjoying it for awhile, and see how the trans enjoys double the power. :D

Unfortunately too many people have moved solely to Facebook groups.
 

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Discussion Starter · #6 ·
Haha. Yeah, yours is gonna be hating life after awhile. Seems the 6L80 is pretty happy up to the 700 mark assuming good tuning. After that, it's a guessing game of when it goes.
 

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I'm interested to see if there was a significant power loss with the valves in the Xforce closed vs open. Car sounds good (makes me want to get LTs) and agreed, very clean install looks like.

Nice results!

-J
 

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Discussion Starter · #8 ·
I'm interested to see if there was a significant power loss with the valves in the Xforce closed vs open. Car sounds good (makes me want to get LTs) and agreed, very clean install looks like.

Nice results!

-J
Yeah, me too. We almost did that test, but didn't want to take up more dyno time than needed since I'm pretty much never gonna go WOT with the valves closed.

And thank you. Tried my best to take my time and have things neat.
 

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Discussion Starter · #10 ·
The GT mufflers I run on the street are close to a 100 whp penalty at full send. Still, I wouldn't street drive without them.
Yeah, I thought I caught that in the video. I'm not sure mine would be that much loss since it's still a 3-inch in and out on the mufflers.

It is really nice to open/close on demand. I drive a fair bit with it open, but it's a little resonant sitting at stoplights, so I close it then. And once cruising on the highway, they're always closed, then it's almost like stock.
 
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I've been waiting for this thread for awhile despite the fact I've been getting updates every several days since you started this project. So glad everything worked out and met your goal!
 
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Extremely nice build. Rims "appear" to be 19's so tire size? Plan on making any passes at the track? If so, what drag setup will you be running?
 
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Very nice! I may be starting to source LSA parts soon as well. Got a friend with a CTSV who is going with a Kong ported blower and I'll be buying his oem blower and injectors. I'll have to source a lid, though. I may be coming to you for tips/part numbers if you have those readily available.
 
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Discussion Starter · #14 ·
I've been waiting for this thread for awhile despite the fact I've been getting updates every several days since you started this project. So glad everything worked out and met your goal!
Thanks! And thanks for the help with all the suspension part numbers and such.

Extremely nice build. Rims "appear" to be 19's so tire size? Plan on making any passes at the track? If so, what drag setup will you be running?
They are 19s. Front is 245/40/19, rear is 275/35/19. Yes, going to the track this weekend. I have a pair of MT ET Street S/S on Camaro 18s. Tires are 285/40/18.

Very nice! I may be starting to source LSA parts soon as well. Got a friend with a CTSV who is going with a Kong ported blower and I'll be buying his oem blower and injectors. I'll have to source a lid, though. I may be coming to you for tips/part numbers if you have those readily available.
Thanks! And happy to help. I think the lids are starting to come back down in price now. They used to be about $650 new with the intercooler, then all the supply chain crap made the price double or triple that.
 
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It is really nice to open/close on demand. I drive a fair bit with it open, but it's a little resonant sitting at stoplights, so I close it then. And once cruising on the highway, they're always closed, then it's almost like stock.
(One of the) best parts about the exhaust. When I start it up before leaving for work, with the valves closed, it only has a slightly louder burble, almost imperceptible. My neighbor's S6 is louder. On the way to work on the highway, it's so quiet, like someone just turned down the bass and mid on the radio that is the engine.

I wish I got the updated looking fobs like I see on XForce's website but oh well.
 

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Discussion Starter · #16 ·
(One of the) best parts about the exhaust. When I start it up before leaving for work, with the valves closed, it only has a slightly louder burble, almost imperceptible. My neighbor's S6 is louder. On the way to work on the highway, it's so quiet, like someone just turned down the bass and mid on the radio that is the engine.

I wish I got the updated looking fobs like I see on XForce's website but oh well.
Yep! Cruising on the highway is nice with it closed.

I'm not sure which updated fobs you're talking about. Mine look like the ones on the website, black and silver with A and B buttons.
 

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