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Low Dyno Numbers PLEASE HELP!!!

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Old Aug 28, 2007 | 11:03 PM
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Default Low Dyno Numbers PLEASE HELP!!!

I am at my wits end with this car!!! Can someone please look over my mods and tell me what could possibly be wrong???

98 Corvette
Dart 205 Heads- Right out of the box
Texas Speed Off Road Headers and X Pipe
B&B Exhaust
Blackwing Air Intake
160* Thermostat
Custom Grind Cam
Forged Bottom End- 10.9:1
LS6 Intake

The car is an Auto and made 365RWHP on a 100* day. I know thats hot weather but then again it shouldnt hurt it that bad. I was figuring on the 420-450 range. Something else thats kind of weird is my other car thats a 99 A&A car was down 60RWHP on the same day and same dyno. Do you think it was just the air or is there something wrong??? For some strange reason I have a feeling its the MSD Spark Plug wires, I have not liked them since I bought them. Does anyone have any experience with this???
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Old Aug 28, 2007 | 11:28 PM
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I dont see how the sprak plug wires would have a loss in HP......I have them on mine, but havent laid into the pedal cause still breaking in the clutch.....My mods are in my sig......I put down 423rwhp on a mustang dyno with the clutch slipping a bit....
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Old Aug 29, 2007 | 06:28 AM
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Was your converter locked during the pull?

Can you post the curve?

What is the cam specs (do you have them)?

When is the last time you cleaned the air filter? Believe it or not my Vararam with a dirty filter put me down 20 hp, we blew it out and the dyno curve came right up.

The Dart's have excellent valve springs, but they are a beehive design and are installed with a somewhat reduced height. Is your lift over 0.600"?

If the local weather information is incorrect in the dyno software that can account for what you are seeing as well from what I have read.

You need to list the variables and examine each one, one at a time to sort this out. I have made modifications with negative results and it comes down to doing some good sleuth work to find the problem. Hang in there
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Old Aug 29, 2007 | 12:21 PM
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do you have a bigger stall? do you have gears? was the car tuned or just put on the dyno? what was the air fuel ratio? did it have any knock retard? more questions to answer
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Old Aug 29, 2007 | 01:26 PM
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Originally Posted by silver01z06
do you have a bigger stall? do you have gears? was the car tuned or just put on the dyno? what was the air fuel ratio? did it have any knock retard? more questions to answer
Stock converter, 3.15 gears, tuned on the dyno to 13:1, no KR (30* timing up top)
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Old Aug 30, 2007 | 08:02 AM
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The cam specs:

Intake 224/.581
Exhaust 230/.592
LSA 114
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Old Aug 30, 2007 | 10:03 AM
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The flow numbers on these heads dont look too great but still it should be making more power. Could it possibly be a lifter issue???
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Old Aug 30, 2007 | 11:35 AM
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Originally Posted by vettenuts
Was your converter locked during the pull?Yes it was locked on the highest pull

Can you post the curve?I will call and try to get the graph emailed

What is the cam specs (do you have them)? 224/230 .581/.592 114LSA

When is the last time you cleaned the air filter? Believe it or not my Vararam with a dirty filter put me down 20 hp, we blew it out and the dyno curve came right up.Cleaned filter before going to the dyno

The Dart's have excellent valve springs, but they are a beehive design and are installed with a somewhat reduced height. Is your lift over 0.600"? I have upgraded valvesprings and the lift is not over .600

If the local weather information is incorrect in the dyno software that can account for what you are seeing as well from what I have read.

You need to list the variables and examine each one, one at a time to sort this out. I have made modifications with negative results and it comes down to doing some good sleuth work to find the problem. Hang in there
Questions answered
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Old Aug 30, 2007 | 05:47 PM
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Personally, seeing as your other car was down 60hp, on the same day, on the same dyno, I believe that the dyno reading is the culprit, for whatever reason, and the numbers you're seeing are artificially low.
Ed
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Old Aug 30, 2007 | 08:54 PM
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Nothing "pops out". Any other dyno's in the area where you could get a 2nd run? Would hate to see your start chasing down a bunch of stuff only to find out the dyno was the issue.
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Old Aug 30, 2007 | 09:27 PM
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Originally Posted by vettenuts
Nothing "pops out". Any other dyno's in the area where you could get a 2nd run? Would hate to see your start chasing down a bunch of stuff only to find out the dyno was the issue.
Is there any chance of it being the converter??? I am noticing when the car shifts I get KR. On the dyno it has no KR but if you drive it on the street and punch it when it goes into the next gear it picks up some KR.
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Old Aug 30, 2007 | 10:45 PM
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Check out the TCI converter I have posted in parts,with the cam you have it certainly couldn't your setup.
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Old Aug 31, 2007 | 09:26 AM
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I have a stock converter for sale, cheap, if you're interested. It has about 20K on it. It operates absolutely perfectly. The only reason I replaced it is I went to a Yank SS3200.
Ed
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Old Aug 31, 2007 | 11:54 AM
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I just came from a different dyno, SAE numbers were 376/378. Somewhat better but still not what I am looking for. I did notice it was leaking tranny fluid where the B&M cooler lines go from metal to rubber. I wonder if line pressure would have anything to do with the power problem? I removed the air filter and that smoothed the graph out a lot, it took the dip out at 5500.
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Old Aug 31, 2007 | 05:32 PM
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Can you post the curves?
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Old Aug 31, 2007 | 06:20 PM
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Originally Posted by vettenuts
Can you post the curves?
This is in STD the SAE numbers were 376/378
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Old Aug 31, 2007 | 06:52 PM
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What are your rear gears? That seems like a lot of MPH for 3rd gear (1:1).
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To Low Dyno Numbers PLEASE HELP!!!

Old Sep 1, 2007 | 12:23 AM
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Thats too much timing for your setup.It WILL detenate on the street.

Also looks like an unlocked converter graph which will show less hp.
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Old Sep 2, 2007 | 11:55 AM
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Originally Posted by vettenuts
What are your rear gears? That seems like a lot of MPH for 3rd gear (1:1).
3.15 I thought it was a high MPH as well. The converter was locked using hptuners for this pull.
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Old Sep 2, 2007 | 09:24 PM
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Originally Posted by 95BlueBomber
3.15
OK, the numbers some out OK for the MPH on the graph.
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