c5z headers & intake dyno results
Thread Starter
Teching In
Joined: Jun 2017
Posts: 11
Likes: 0
c5z headers & intake dyno results Had my car tuned last week after getting the long tubes and the intake installed. Overall I'm very happy with the numbers considering the conditions and the conservative tune, the car feels and sounds amazing. Shout out to Powertech Performance in St. Pete. If any of you guys are in the Pinellas/St. Pete/Tampa area I highly recommend you check them out. Joe (owner & tuner) is an awesome guy and the LS platform is his expertise. He walked me through the tune while it was on the dyno and explained what changes he was making as he went along.
Car: 04 c5 z06, 40k miles
Mods: American Racing 1 3/4" long tubes, off-road x-pipe no cats connected to stock Ti axle-backs. Vararam B2 intake w/ power duct.
Conditions: 92F outside/114F in dyno room, 85% humidity, approx 15ft above sea level.
Stock Baseline: 351hp & 329tq
Final Pull: 388hp & 370tq at only 20 degrees of timing.
Car: 04 c5 z06, 40k miles
Mods: American Racing 1 3/4" long tubes, off-road x-pipe no cats connected to stock Ti axle-backs. Vararam B2 intake w/ power duct.
Conditions: 92F outside/114F in dyno room, 85% humidity, approx 15ft above sea level.
Stock Baseline: 351hp & 329tq
Final Pull: 388hp & 370tq at only 20 degrees of timing.
Trending Topics
Thread Starter
Teching In
Joined: Jun 2017
Posts: 11
Likes: 0
I asked him the same thing, I was a little surprised by how low he kept the timing too but the more timing he added the more knock he would start to see. Very minimal knock but still knock. He said the heat and humidity was really holding him back from squeezing the last few degrees of timing out. We agreed to leave it conservative because it is my daily driver.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
Teching In
Joined: Jun 2017
Posts: 11
Likes: 0
I just felt the 1 3/4" was better suited for a stock 346ci daily driving in the city. I might have picked up a couple peak hp with 1 7/8" but I didn't want to sacrifice any mid range torque so I played it safe.
That's strange. Even in dead of summer I've been able to get 27.5* out of my LS1 with LS6 heads and now the LS2 which has even more compression (approx 11.2:1).
That humidity is pretty insane though.
Either way, good numbers.
That humidity is pretty insane though.
Either way, good numbers.
Thread Starter
Teching In
Joined: Jun 2017
Posts: 11
Likes: 0
Yeah it is a little unusual that we couldn't go past 20 degrees without seeing some knock. Most likely some combination of variables like heat/humidity, heat soak, bad gas, blow-bye in intake (I don't have a catch can yet and he mentioned that the intake manifold was very dirty) etc... who knows.
'Back pressure' be damned.
Jus' sayin'.....
KW
A buddy of mine just switched from 1 3/4" to 1 7/8" headers (both Speed Engineering as well) and picked up exactly 5 rwhp. It was the same dyno before and after. He has a heads and cam LS1 to boot.
Thread Starter
Teching In
Joined: Jun 2017
Posts: 11
Likes: 0
How did the curves compare? Everyone but my tuner seems to recommend 1 7/8" but I have yet to see a good back to back comparison. I find it hard to believe that going up in primary size will have zero effect on the low/mid range and will only extend peak torque to gain a couple hp. Either way the difference is not nearly significant enough to make the switch.
How did the curves compare? Everyone but my tuner seems to recommend 1 7/8" but I have yet to see a good back to back comparison. I find it hard to believe that going up in primary size will have zero effect on the low/mid range and will only extend peak torque to gain a couple hp. Either way the difference is not nearly significant enough to make the switch.
I was going to ask a similar question. We always look at peak HP for comparison sake, but in reality acceleration happens under the curve.
;