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-   -   Dyno fudging the numbers?? (https://www.racingjunk.com/forums/showthread.php?t=21427)

dynaguy03 08-03-2008 06:13 PM

Dyno tuning finished
 
Ok Gents .. thanks everyone for your input.. The day on the dyno actully was only a few hrs. over 2 days. We broke the cam in first day and checked everything.. let it cool down overnight re-tourqued the heads and went over everything again
Day 2 we made a few pulls - made 2 jet changed on a 750 carb and adjusted the timing a few times. By the readings he explained the 750 was too small so i threw on my 850 made 2 pulls adjusted jets again .
Was pretty drama free.. the peak hp was at 6805 rpm the peak tourque was @ 5900 but stayed the same till 6150rpm.
Wound up 624hp and 553ft/lbs within a rpm range of 4300-7000 on this 388ci chevy. Im pretty happy.
Of coarse we could have worn it out on the dyno but i felt once we tweaked it .. carb and timing it was smooth sailing
Thanks for all your comments and input!

Keith

dynaguy03 08-03-2008 06:20 PM

motor we dyno'd
 
388 ci sbc 13-1 -,canfield heads extensive bowl ,port and runner work, 208-160 valves - super victor intake, plenum work,port matched, AED 850 carb, 1 in spacer, jesel shaft rockers, comp cams roller lifters, rockers,mech roller cam.. i dont have the cam card and everything is still at the builder, eagle rotating assembly J&E forged small dome pistons, ati super dampener, msd dist./wires,crank trigger. Comp cams custom cam 640 in 630 ex. installed at 108 -timing 37 degrees.

promodjohn 08-05-2008 09:45 AM

DYNO
 
You are paying all that money for the dyno so insist on being there with the builder.If they don,t allow that I would not trust them been burnt too many times.USE SOMEONE ELSE!!!!!!!!!!!!!

CarbGuy 08-07-2008 03:24 PM

Re: Dyno fudging the numbers??
 

Originally Posted by dynaguy03
How would i know if the numbers on the dyno werent manipulated to falsely achive the numbers??

thanks
In advance

Simple, get both the raw (uncorrected) numbers, and the corrected numbers. Then find out what the weather was during the dyno test (Air inlet temp, humidity, and barometric pressure) from that you can go online and determine what the air correction for that day should have been. If the correction is right you're usually pretty good. Depending on the type of dyno used there are other ways, but as stated before a dyno is a tuning tool used for baselining an engines performance, and that's it.

cncmotorsports 08-20-2008 07:01 PM

Sounds like your dyno numbers are pretty close for a super flow dyno, they generally ready 5-8% higher than most other dyno's. On Our DTS dyno, I would guess it would have made around the 585-590 HP mark.
Either way sounds like all is well.
Would have been neat to have tried the AED 950HOM on there, bet it would be good for another 10-15 HP


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