crazy dyno = bad opti ???
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TECH Fanatic
Joined: Jan 2005
Posts: 1,162
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From: St. Augustine, FL
crazy dyno = bad opti ??? So, I dyno'ed my SS back in January when I had shorty headers with stock cat-back & hypertech programming. The dyno showed 274HP and 304ft/lb. I heard the numbers and figured the car is just tired and waiting for a rebuild but, when I look at the graph,... OMG! right about 4500RPM the hp and torque lines get crazy. I mean, basically it was a steady climb right to about 4500 and it took a major ****. I raced the car a few times in the past and remember it would feel as if the car stopped pulling around 4500-5000. I mean, it just felt like it bogged down and I suppose now I'm just looking at the same thing on the dyno sheet. I put in an LT4 knock module thinking that might be it. I also changed out the entire exhaust since then. The car feels like it pulls straight through and doesn't bog down at the higher RPMs like it used to. I went to the dyno again yesterday march 30th and the results were 279HP and 319ft/lb. with that same crazy **** at about 4500rpm. I know I really need to post pictures for anyone to better understand but I dont have a way to do it right now. If anybody would like to see my dyno sheets, I have them saved as jpg files and can e-mail them to you. PM me.
My BIG QUESTION is : Does this sound like an opticrap symptom?
ALSO : Does anyone have any dyno results showing what a bad opti will look like???
My BIG QUESTION is : Does this sound like an opticrap symptom?
ALSO : Does anyone have any dyno results showing what a bad opti will look like???
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Joined: Aug 2004
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Thread Starter
TECH Fanatic
Joined: Jan 2005
Posts: 1,162
Likes: 0
From: St. Augustine, FL
I wont be able to e-mail anybody the pictures till friday since I'm on duty and stuck on my ship all day/night until tomorrow. 
I really appreaciate any help/advice I can get.
I really appreaciate any help/advice I can get. Thread Starter
TECH Fanatic
Joined: Jan 2005
Posts: 1,162
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From: St. Augustine, FL
The Air/Fuel :
The first dyno I ran back in January had shorty headers with all emissions hookups and I was running with the HTPP3 tuning. The air/fuel line was running at like 11.5 flat up to 4000rpm. Between 4000 and 4500 it rose quickly to 12. From 4500 to 6000 it has a slight hump/curve where it peaked at 12.5 for the run
The second dyno which I ran the other day was with pacesetter long tube headers hooked up to the TSP x-pipe true dual 3" inch exhaust (no cats), LT4 Knock module installed, removed secondary air, removed and capped the egr, installed breather and plugged PCV spot on TB. Also, The rear O2 sensors are not hooked up and the front two had to be extended for the long tubes. No HTPP3 tuning. The air/fuel on this run looks like the exact same line, just minus one. Like instead of starting at 11.5 flat it was 10.5 flat and so on.
The crazyness in the hp line starts at that jump in the fuel ration between 4000 and 4500. And after that change it just goes completely wacky and basically starts declining as its jumping up and down. Thats the best description I can give in words. Send me a PM with your e-mail addresses if anyone would like to see the dyno sheets. Again, I really appreciate all the info and suggestions I can get. Thanks guys!
The first dyno I ran back in January had shorty headers with all emissions hookups and I was running with the HTPP3 tuning. The air/fuel line was running at like 11.5 flat up to 4000rpm. Between 4000 and 4500 it rose quickly to 12. From 4500 to 6000 it has a slight hump/curve where it peaked at 12.5 for the run
The second dyno which I ran the other day was with pacesetter long tube headers hooked up to the TSP x-pipe true dual 3" inch exhaust (no cats), LT4 Knock module installed, removed secondary air, removed and capped the egr, installed breather and plugged PCV spot on TB. Also, The rear O2 sensors are not hooked up and the front two had to be extended for the long tubes. No HTPP3 tuning. The air/fuel on this run looks like the exact same line, just minus one. Like instead of starting at 11.5 flat it was 10.5 flat and so on.
The crazyness in the hp line starts at that jump in the fuel ration between 4000 and 4500. And after that change it just goes completely wacky and basically starts declining as its jumping up and down. Thats the best description I can give in words. Send me a PM with your e-mail addresses if anyone would like to see the dyno sheets. Again, I really appreciate all the info and suggestions I can get. Thanks guys!
Last edited by hyperzone; Apr 1, 2005 at 01:14 PM.
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TECH Apprentice
Joined: Dec 2004
Posts: 325
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From: Charleston, SC
Originally Posted by Crazyz28
Does it look anything like mine? 
This was caused by a spark plug wire hitting the power steering pump and arcing. But it did make for a CrAzY dyno graph
Ryan
This was caused by a spark plug wire hitting the power steering pump and arcing. But it did make for a CrAzY dyno graph
Ryan
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