Low Dyno Numbers PLEASE HELP!!!
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 2,586
Likes: 2
From: Bardstown Kentucky
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???
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???
Melting Slicks
Joined: May 2007
Posts: 2,533
Likes: 1
From: North Aurora IL
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....
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
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
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
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 2,586
Likes: 2
From: Bardstown Kentucky
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 2,586
Likes: 2
From: Bardstown Kentucky
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
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
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Safety Car
Joined: Oct 2000
Posts: 4,949
Likes: 10
From: Monticello MN
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
Ed
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
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.
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 2,586
Likes: 2
From: Bardstown Kentucky
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.
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 2,586
Likes: 2
From: Bardstown Kentucky
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.
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 2,586
Likes: 2
From: Bardstown Kentucky