Numbers?
Thread Starter
8th Gear
Joined: May 2018
Posts: 8
Likes: 0
Numbers?
So long story short I spent almost 5k with parts and labor on a tsp 228/600 r cam, tsp long tubes, xpipe (no cats) b&b bullet exhaust, halltech stinger intake, new Springs, timing parts etc. I was running mid grade gas instead of premium honestly cause I didn't drive it much. So a couple of pulls with the hp tune it only made 341 🤔🤔🤔 I'm being told my injectors are at 95 % cap, and they also tuned for the lower octsne. My mind baffles me because I've been told those mods I should be at least 400 to the tires. Should I go back to the shop and demand another tune? The tune the way it is now fuel trims look steady across the board.
Pro
Joined: Feb 2013
Posts: 535
Likes: 92
From: Raleigh NC
What year is your car? Manual or automatic? Mileage?
The graph shows 367 hp, but you said it made 341. Is one number STD and one Corrected? I do agree, that's seems a little low. But your stock numbers seem low too, so it may be that dyno just reads low. Typically a manual loses roughly 15% through the drivetrain. So a stock number of 268 would be 315 at the motor, which is lower than the factory rating. It looks like you picked up 100rwhp, so that's significant and in line with the mods you made.
Running lower octane fuel is costing you power. To compensate for the lower octane, they have to pull timing out of the tune. Why spend $5k on performance work and then lose hp by running cheap gas?
I'm surprised your injectors were maxed out at that power level. But if that's the case, then I would consider getting larger injectors (will require a new tune). Also, 2001+ got the LS6 intake manifold, which is worth some hp.
How does the car run? If it pulls strong, I wouldn't get too hung up on dyno numbers.
The graph shows 367 hp, but you said it made 341. Is one number STD and one Corrected? I do agree, that's seems a little low. But your stock numbers seem low too, so it may be that dyno just reads low. Typically a manual loses roughly 15% through the drivetrain. So a stock number of 268 would be 315 at the motor, which is lower than the factory rating. It looks like you picked up 100rwhp, so that's significant and in line with the mods you made.
Running lower octane fuel is costing you power. To compensate for the lower octane, they have to pull timing out of the tune. Why spend $5k on performance work and then lose hp by running cheap gas?
I'm surprised your injectors were maxed out at that power level. But if that's the case, then I would consider getting larger injectors (will require a new tune). Also, 2001+ got the LS6 intake manifold, which is worth some hp.
How does the car run? If it pulls strong, I wouldn't get too hung up on dyno numbers.
Thread Starter
8th Gear
Joined: May 2018
Posts: 8
Likes: 0
I hit the wrong number lol. It's a 2003 manual. The stock numbers were low because when I installed the halltech intake my check engine light was on and apparently the previous owner wired the maf wrong. Anyways I was only running mid grade gas because I was told no need to run 93+ because it wouldn't make much difference on stock. I forgot to fill it with premium before it went to the shop. Since then been running 93. It goes back Thursday for a few tweaks. It pulls nice and hard. Beat a Dodge challenger hemi last week.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Safety Car
Joined: May 2016
Posts: 4,672
Likes: 1,854
From: Erlanger, Kentucky
Don't get hung up on the dyno numbers too much. How the car feels and performs is what really counts. Best place to test performance on at the drag track.
It is possible that your injectors could be holding you back. If they are near maxed out and not able to provide enough fuel to keep up with the increased airflow, that would definitely limit your power. Only one way to find out, get bigger injectors and a re-tune.
It is possible that your injectors could be holding you back. If they are near maxed out and not able to provide enough fuel to keep up with the increased airflow, that would definitely limit your power. Only one way to find out, get bigger injectors and a re-tune.
Safety Car
Joined: Sep 2001
Posts: 4,161
Likes: 554
From: Glenbeulah Wi
Don't worry about the injectors costing you power. Your afr is nice and flat in the high 12's all the way to max power. Additional fuel will not make more power. These cars are sensitive to detonation so you should be running super unleaded fuel. Even a stock vette engine will pull timing (power) with 89 octane fuel. Since they built the tune for 89 octane fuel they may have pulled timing to keep it from detonating so using 93 octane fuel now may not add any additional power. Ask the tuner how the tune is built.
Thread Starter
8th Gear
Joined: May 2018
Posts: 8
Likes: 0
It just went back in for a miless rich idle to lean it some. Added a couple degrees in the top end to comp for the higher octane. Won't get another dyno tune again till I do heads, intake, Tb, and injectors next year. Over all I'm happy my car sounds mean and pulls good. Also going with a new clutch too. My goals are max hp without changing the fuel pump lol which I read is about 550 rwhp. So that's the goal.