Dyno question
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From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Dyno question
This might have to go in the Tech/Performance section.....
Over the summer I had my 93 A4 dynoed and I was wondering if my numbers might have been higher if she wasn't so hot. When I got to see the run I noticed the fans were on.... meaning the coolant temp was around 229-232 (thats when my fans click on when the a/c is not on) and the oil around 220. I was still happy with the results 254/286 at the tire. Anyone think it might have been higher if the engine temps were lower?
BTW: Damn sweet seeing my car up there. And boy did it sound Gooood! Gave me chills.
Over the summer I had my 93 A4 dynoed and I was wondering if my numbers might have been higher if she wasn't so hot. When I got to see the run I noticed the fans were on.... meaning the coolant temp was around 229-232 (thats when my fans click on when the a/c is not on) and the oil around 220. I was still happy with the results 254/286 at the tire. Anyone think it might have been higher if the engine temps were lower?
BTW: Damn sweet seeing my car up there. And boy did it sound Gooood! Gave me chills.
Melting Slicks
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From: Texas
My numbers are in my sig (or still should be, I'll check after I hit submit). It was a very hot day and my car had been driving around all day before hand. Also had a tranny leaking every where if that affected it at all.
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Motor temp and climate will play a role in the peak performance of your car... but not enough to make a difference... in other words you aren't going to loose 50hp just because your motor was over 200* and it was a 95* day outside. I'd say you may have lost 10hp tops in that circumstance... but I could be wrong.
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From: Punta Gorda, FL
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'13- '14
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Interesting. Did mine July 10th, and it was pretty damn hot out. I pulled a 286/326 at the rear. I'd love to see what it would do right now (its 49 out)
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From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Originally Posted by vetteweiser
Interesting. Did mine July 10th, and it was pretty damn hot out. I pulled a 286/326 at the rear. I'd love to see what it would do right now (its 49 out)
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From: Punta Gorda, FL
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'13- '14
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LT4 Roller Rockers, K&N filter, removed the mufflers. Thats been it 
(you already know this now, but figured I'd answer for the rest of the crowd)
(you already know this now, but figured I'd answer for the rest of the crowd)
Melting Slicks
Joined: May 2002
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From: Severna Park MD
Temps on dyno
The outside temperature is corrected for SAE standard on the numbers and charts you get. I'm not too sure it corrects 100% for the ambient humidity, but for temp it is correct.
The LT1s will run much better in cold air and produce more power, as much as 40HP on a really cold day. But that is corected in your numbers. Your car was too hot that day for a good result for that engine.
What is not corrected is the running temperature of your engine. If you installed a 160 T-stat and adjusted the fans to keep the water temp in a 180* range during the pull it would put down more power than you got at the temps you were seeing. Without modding the engine to run cooler you could get a better result on a cold day just because the cooling of the car works better sucking in the cold air through the radiator. Maybe 7.5 to 10 HP.
It's certainly worth $75.00 to do a run on a cold day.
My best numbers were on a day below freezing in December, and I was the first car to run at 09:00. We were all ducking inside to warm up that day. The SAE correction factor for my run that day was 0.90.
The LT1s will run much better in cold air and produce more power, as much as 40HP on a really cold day. But that is corected in your numbers. Your car was too hot that day for a good result for that engine.
What is not corrected is the running temperature of your engine. If you installed a 160 T-stat and adjusted the fans to keep the water temp in a 180* range during the pull it would put down more power than you got at the temps you were seeing. Without modding the engine to run cooler you could get a better result on a cold day just because the cooling of the car works better sucking in the cold air through the radiator. Maybe 7.5 to 10 HP.
It's certainly worth $75.00 to do a run on a cold day.
My best numbers were on a day below freezing in December, and I was the first car to run at 09:00. We were all ducking inside to warm up that day. The SAE correction factor for my run that day was 0.90.
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Melting Slicks
Joined: May 2002
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From: Severna Park MD
Originally Posted by BigTexas
How hard/easy is it to adjust the fans? I would like to do that to my 95. Thanks
B.
B.
LT1 edit can change these as well as the temp to bring on the high speed fan. The Hypertech changes only the low speed fan setting.
The cost af a license for LT1 edit is a lot for just these changes, and you need a laptop, etc. If you know anyone who has LT1 Edit for pesonal use they can do the change for you.
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by WZDADS
What temp should the car be at when doing a pull?
A dyno is basically a standing Ľ mile... or the same principal. you are gunning the motor to see what it's top performance is... so I figure that the motor will pull harder when cooler... so why not dyno with a cooler motor...
someone correct me if I'm wrong.
Melting Slicks
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From: Severna Park MD
Originally Posted by kwik_ta
A dyno is basically a standing Ľ mile... or the same principal. you are gunning the motor to see what it's top performance is... so I figure that the motor will pull harder when cooler... so why not dyno with a cooler motor...
It helps to go to the dyno on a cooler day, just like it helps to get a smog check in December instead of July.
Drifting
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From: Mobile AL
St. Jude Donor '05
Originally Posted by FELNGR8
With the 94-96 this change is a programming task. Either buy a Hyper-Crap to change this, the rev limit, and the gear ratio, or get a dyno tuner to change it while running a tuning session. I bought the hypertech to change these things and then found out the limitations.
LT1 edit can change these as well as the temp to bring on the high speed fan. The Hypertech changes only the low speed fan setting.
The cost af a license for LT1 edit is a lot for just these changes, and you need a laptop, etc. If you know anyone who has LT1 Edit for pesonal use they can do the change for you.
LT1 edit can change these as well as the temp to bring on the high speed fan. The Hypertech changes only the low speed fan setting.
The cost af a license for LT1 edit is a lot for just these changes, and you need a laptop, etc. If you know anyone who has LT1 Edit for pesonal use they can do the change for you.
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by kwik_ta
I figure that the motor will pull harder when cooler... so why not dyno with a cooler motor...
Your engine puts out what it puts out. Getting the last possible hp on the dyno doesn't make the engine any more powerful, it just gives you the most braggin' rights.
...which doesn't win races.
A cold day and a cold engine may gain you 15hp on the dyno chart, but won't make a bit of difference when that pesky Mustang GT pulls up beside you on the freeway and drops it down two gears. At that point you got what you got (as they say).
Larry
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From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Originally Posted by FELNGR8
A dyno operator should let your engine cool between runs, if they don't you are not getting your money's worth. But if you are there for a group session they are not going to waste a lot of time letting one car cool.
It helps to go to the dyno on a cooler day, just like it helps to get a smog check in December instead of July.
It helps to go to the dyno on a cooler day, just like it helps to get a smog check in December instead of July.
Any body know a good chip for the 93 LT1?? Thinking about adding 1.7's rollers, is that too much profile? Don't want to hit the pistons.
Melting Slicks
Joined: May 2002
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From: Severna Park MD
Originally Posted by code5coupe
You are absolutely right...but what's the point?
Your engine puts out what it puts out. Getting the last possible hp on the dyno doesn't make the engine any more powerful, it just gives you the most braggin' rights.
Your engine puts out what it puts out. Getting the last possible hp on the dyno doesn't make the engine any more powerful, it just gives you the most braggin' rights.
I think my last dyno pull was a little low because it was a rainy day but I'm not going back just because of that.
Do you realize how many guys go to extremes trying for perfect weather in the fall to brag about their "New Best"? Nobody's listed best ET was run on a 90 degree day with the engine running at 230 degrees.
I could run 0.2 faster in my car right now if I went out on a 40 degree day to specifically run a time to brag about. Well, not right now today because my throttle body is in Illinois and not on my engine.
