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Old 08-05-2018, 05:29 PM
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Nighteagle1981
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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.
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Old 08-06-2018, 05:23 PM
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99blkfrc99
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Post dyno graph. What heads?
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Old 08-06-2018, 05:37 PM
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Nighteagle1981
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Heads are stock atm
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Old 08-06-2018, 06:02 PM
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Originally Posted by 99blkfrc99 View Post
Post dyno graph. What heads?

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Old 08-07-2018, 12:33 AM
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sirdano
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If your car is a 97-2000 my tuner said the head are the biggest hold back on power on these cars.
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Old 08-07-2018, 06:26 AM
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Are the blue numbers stock?
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Old 08-07-2018, 10:15 AM
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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.
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Old 08-07-2018, 10:31 AM
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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.
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Old 08-07-2018, 11:51 AM
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Big Mack beat me to it. That was along the lines of what I was going to say. Curve looks good. Dyno's vary. Trap speed don't. Go run it at the track will give you an indication of accurate hp.
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Old 08-08-2018, 07:21 PM
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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.
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Old 08-12-2018, 07:57 AM
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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.
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Old 08-12-2018, 12:02 PM
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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.
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