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FlyinRyan 10-25-2009 11:32 PM

Sleepy4.7 ON THE DYNO!!!!!
Myself, Sleeper, and Chaz went down on a whim to the Big Valley Performance dyno day. BVP is a predominantly import shop off of Orange Blossom Trail in Orlando. They have an in-house Dynojet Eddy Current dyno, which I'm told is 1 of 13 on the East Coast. They charged us 65 each for 3 pulls. The dyno was AWD, which is why I decided to go.

For quick reference:
Ryan (myself): '02 4.7 WJ, Hybrid lift, 31" tires, FRP prototype TB, homebrew POS intake with ginormous 6x11" UNI filter, SCT custom tuning, 3" ceramic coated exhaust
Sleeper: SN95 mustang V6 with Mark 8 Lincoln 4.6 DOHC swapped in, AOD w/ 3.73s, big K&N, X pipe, flows
Chaz: 4th gen Camaro V6 5 spd, intake lid, pacesetter shorty headers, flowmaster muffler

We got there and once we figured out how everything would play out, we sat and watched an Evo X be tuned. this took 3.5 HOURS. Apparently the Evo X requires the use of a special extra deep-threaded spark plug that can only be purchased through the dealer. They had to physically run out to the dealer , get new plugs. It was worth the wait, as it eventually put down 490/415 on pump gas + meth. the car was an absolute monster. Very little of this time was used towards tuning, the downtime of troubleshooting the plugs & the parts run took up alot of that time spent with it on the rollers.

At about 6 pm, the Evo finally rolls off the dyno, and Sleeper goes. One thing that was kinda cool/interesting about BVP is that they let us operate the dyno ourselves. Specifically, we were allowed to be in the drivers seat while the car was on the rollers. No offense to Sleeper, but I guess he hasn't really ever watched a dyno closely enough to know what he was doing...he ran it WOT through the gears, banging the rev limiter on several occassions, until he hit the top of 3rd. his motor did not like this kind of treatment, as it billowed blue smoke out the tailpipes after the 1st run in particular. Once they got it to stop skewing the values, he put down 245/287...which is literally exactly in the range of the 240-250 whp I expected him to put down. He thought he was going to put down 300+ rwhp....I told him he is bound to be disappointed, and sure enough he was. Oh well, it happens.

Chaz had arrived just in time to get on the rollers. He put down several runs , all of which where shut down at 4500. Very interesting as we have been trying to troubleshoot a bogging issue at 4k at the track...Anyhow, a local tuner in the shop (more on that below) believed it was a speed sensor issue , i.e. freaking out due to sensing the front wheels going 0 mph while the rears were doing 100+ mph. Nonetheless, Chaz put down 178/218. Nice job BTW Chaz.

Then it was showtime for me. I had originally planned to be doing some remote dyno-tuning with Sean Powell of KRC Performance during my runs, but at the last minute I found out that the computer used for logging the graphs did NOT have internet. So I was basically stuck using the latest revision I had , a SCT custom 93 octane file I had loaded earlier in the day. My tuner was on dial in case we needed a tweak. I also had my laptop on hand with 15 or 16 files already written to play with.

I have an auto, and no trans control, so I got it to lock in 3rd, and gradually rolled on the throttle. Because it would downshift to 2nd if I dropped the hammer too soon (we had to abort 1 run because of this), I had to wind it up through the gears, get it to lock in 3rd, then at about 70 mph at 3200 rpm I could finally go WOT till about 115ish. The truck was dead consistent, netting 3 back to back to back runs of 180-182 awhp/240 awtq with 107* ambient temps in the dyno room, typical FL humidity, 31" off-road tires and a tune that was intentionally a little conservative. AFR was 12-12.1:1 . There is no doubt in my mind that we could have picked up another 5-10whp had I gone to one of my other files with leaner AFR and in some files more timing. But between my cooling issues, the hot dyno room, and my coolant temp spiking to 240 after every run, I did not want to push the limit. Knowing what it is capable of now, I will likely turn up the wick a little bit for the next dyno day we do as a club. My curve looks awesome- it holds max tq value from 3200 to 4000, and hp builds linearly. I'm very happy with the results.

Jerson (owner of BVP) and everyone at the shop was extremely friendly, supplying us with as much BBQ as we could eat. I would use their facility again.

Robert Palmer 10-25-2009 11:41 PM

Re: Sleepy4.7 ON THE DYNO!!!!!
Badass for the WJ. Too bad there were no pics and video. Love seeing video of dyno runs.

chefalan23 10-25-2009 11:53 PM

Re: Sleepy4.7 ON THE DYNO!!!!!
thats strange the mustang only put down 245. a bolt on 4v usually does 270 rwhp

FlyinRyan 10-25-2009 11:54 PM

Re: Sleepy4.7 ON THE DYNO!!!!!

Originally Posted by Elvis Presley (Post 86632)
Badass for the WJ. Too bad there were no pics and video. Love seeing video of dyno runs.

Check your phone, and there IS a video.....

FlyinRyan 10-25-2009 11:56 PM

Re: Sleepy4.7 ON THE DYNO!!!!!

Originally Posted by chefalan23 (Post 86635)
thats strange the mustang only put down 245. a bolt on 4v usually does 270 rwhp

its a Mark VIII motor, not a cobra motor, thats why.

Also, it's a Dynojet dyno, not a Mustang where you can fudge the numbers some....

B.P.O.D 10-26-2009 09:17 AM

Re: Sleepy4.7 ON THE DYNO!!!!!
awesome bro!!!! where is the vid?!?!?!?!?!

dreamer1213 10-26-2009 05:51 PM

Re: Sleepy4.7 ON THE DYNO!!!!!
Thats awesome Ryan!! Very glad that you got the results you wanted! :D

Scottina06 10-26-2009 06:00 PM

Re: Sleepy4.7 ON THE DYNO!!!!!
would love to see the video

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