Payback hits the chassis dyno
 

Had a great day. AJ rode over to the dyno shop with me and Curtis met us over there. Got her up on the dyno and made my first run. I had the jetting perfect. He was very experienced in drag racing and tuning and said don't touch the jets. I then added timing a few times, bumped the rev chip, and removed the air cleaner. It really liked the timing. I ended up with 41 total and just couldn't go any farther on pump gas. It wasn't detonating but it's loud! I wanted to:D He said the air here sucks and I'd see 20 hp and ftlbs in Cali. My favorite part is 497 ftlbs at 3800 rpm!!!! 491 horse doesn't suck either. Very happy with the performance. I'm sure it will be asked.
Gen VI 489 big block
9.5-1 compression
Dart Pro 1 heads 325cc
.632 Crane hydraulic roller 114lsa
Air gap
850 holley

http://i200.photobucket.com/albums/a...day3-09007.jpg
http://i200.photobucket.com/albums/a...nosheetstd.jpg

Man that dyno vid sounds awesome!! Nice numbers too... so with a 15% estimated drivetrain loss for a manual, you are at 587 crank hp. Is that what you figure?

Also, what octane pump gas you have there? 91 or 93?

It was fun man. The engine dynoed at 593hp at 6000 and 587 ftlbs at 3700. 91 octane Chassis dyno definitely backs that up. It calculates to 17% drivetrain loss on HP and 15% on torque. With our really dry crappy air he said it was right on the money and it was a great motor.

Sunoco Twist...
 

like i said be for one of my fav's....AWESOME VIDEO:thumbsup: :cheers:

Thats BAD ASS Todd I heard the guy in backround say 491 497 I would have had a smile on my face that you couldn't take off with a chisel

Wish we would have had a little 100 Octane to throw in it...bet we could have broken 500hp easy!

:unibrow:

Awesome numbers!! and it sounds wicked too!!!

500hp at the wheels makes for a fun street car. :thumbsup: Sounds awesome in the video.

Are you going to take it to LVMS and see what it will run?

Definitely going to make a trip down the drag strip this year. Not sure with what tires yet. I thought it was interesting that it only gained 1 hp and no torque removing the air cleaner.

love the flat t-courve- i need a ride!!!:thumbsup:

Nice numbers!
 

You have done a really nice job on the car. Way to stay on it and get all of the bugs worked out.

That's great but the poor rear tire's will live a short life.:unibrow:

Awesome Car! :cool:

Nice numbers Todd! Your car is Killer :thumbsup:

That's a nice car Todd!
GREAT NUMBERS!:hail:

That's awesome Todd!! I want a ride this year!! :cheers:

For the dyno did you use 91 octane? 93?

Don't they sell some 100 or C16 at the dragstrip you can throw in her? :woot:

What's your goal/estimate of 1/4 mile ET? Not sure if your 345s are drag radials, but I am gonna start the guessing at 11.50 @ 125mph.

Thanks guys...I can get 100 unleaded at the pump for big bucks. I always run 91 due to that being the highest regular pump gas. There is something me and Frank are cooking up for my first drag at the strip. Stay tuned.:D :D

Sweet numbers Todd ! The more I hear your car the better I feel about using my Magnaflow system, Sounds great. We had a nice 55 degree day in the north east today . Between your Video and working on my buddies 68 with the 509 in it .I got the fever bad. Awesome pull on the dyno.

The 100 octane thing is a myth. if the car does not need it it will run faster on lower octane.

The reason there are different race octanes is you only want to run the lowest you can get away with. My street racer is a pump gas motor and looses a full 1/10th on 110 octane on motor. But needs the 110 to be safe on nitrous.

So long story short, at 9:1 compression, 100 octane would steal power.

500HP at the tires at 3500LBS is plenty to run high 10s. One trip to the dragstrip and I bet I am sending him double adjustable shocks and Prodigy Bar ends!

Sounded awesome for that short burst,made my #'s look wimpy by comparison...but my little 383 sounded like a freight train all the way up to 6800rpms.
You got a good 100 lb ft of torque on me (391 rwtq),would love to hear what your 1/4 mile times are...congrats,awesome looking car,especially in Black!:thumbsup:

Gotta love big blocks...

I agree that to much octane will actually rob power. We were just talking about a mix to say 95-97 octane where I could go to 44 degrees total and not worry about detonation to try and get that 500/500.:D Going from 39 to 41 gained me 8 ftlbs and a 2 horse. Every time I added timing I gained. He had mentioned he has seen many big blocks love 44 degrees due to the large head chamber. If I was to try for the 500/500 I would mix 50/50 91/100 unleaded, change the pre load on the lifters to one full turn for better performance over 6k, and try 42 then 44 degrees of timing. I won't dyno it again unless I make a major change. To big a hastle getting it on that rack.

not out here in vegas... with good 60fts it should run mid-to low 11s, with a GREAT 60ft i could see a high 10 though.
yea the car has some serios traction problems.lol
when todd just lighty accelarates to pass a car its starts getting sideways lol

yes it needs stickier tires but i also feel it need some suspension tweaking...

Payback+Traction? :rofl:

Wow nice vid! and nice numbers!

Easy now...with the lack of rain the city streets get really greasy. I can hook it in second gear full throttle on some clean pavement. Pulls really hard. 1st gear is a challenge to say the least:_paranoid

Just saying it's going to be a challenge is all. When you get that beast to hook it's going to be like a catapult shot off an aircraft carrier!

:yes:

Nice numbers and great sound for sure! You might like this, you already might be past the 500hp with those readings. My dyno guy stated when we were running on that dyno that, " the humidity in the brick was off" and it could easily be out by 10-20 hp in your favor.(I guess it's a common problem on that particular dyno) I have no idea what that really means except your numbers are actually higher! Garth (from Leading Edge) did not really want to acknowledge that and the subject was dropped quickly.



No doubt... how many times did the wooden ramps go shooting along the floor for you. ha ha? Full blown clutch/leg work out!

He actually said his dyno was really tight and most guys complained of low numbers. I noticed the sheet says 5% humidity but the weather said 15% yesterday. I'm sure that would effect the correction factor. Oh man my foot was tired after getting it on that rack. I ended up bending a v clamp as well. Glad to hear it may be conservative. What did you end up making on his dyno?

If I recall correctly, Scott ran his 69 with ~500 rwhp and 335 drag radials to the tune of 11.50s. Even though one is a big block and one is LS7, pretty darn similar cars. That's where my prediction still stands.

High 10s? Yeah, if he throws on 15" big n littles, drag shocks, and a wicked clutch dump! :_paranoid

Don't forget I'm at 2500 feet.:unibrow:

530 I think? (the start of hungover no sleep wrench and race). Garth was great, treated us outstanding so I don't want to say anything negative, I'm sure it is tight. Leave it for the dyno techs, they agreed not to agree. lol

Nice...we tried to look it up but he couldn't find it. I think you are onto something with the humidity. I went back and looked at the weather Tuesday at around 2 PM when the car was dynoed. I used a calculator that uses temp vs dew point and the humidity should have been 15%. When I got home that day I checked and it was 15%. The lowest it got was 11% on Tuesday. http://www.wunderground.com/weathers...y=24&year=2009 I thought the HG was off but it's a calculation based on absolute pressure not barometric. I looked at my motorcycle dyon from two years ago and it's right on the money. I also found that the correction factor is based on 0% humidity. So if the humidity was really 15% and the computer used 5% the correction would be smaller than it should have been. I took it one step further and found a calculation. http://wahiduddin.net/calc/calc_hp.htm With the correction factor at 5% humidity, my engine would have made 93.1% of the power it would have created with perfect conditions or the standard. With 15% it would have made 92.8% of perfect conditions or the standard. So only .3% difference. Still shy but right at about 499 ftlbs. One more degree of timing and I'm there easy.:D

Just for fun...in Huntington Beach today I would be making 102.2% of the standard. 66 degrees/58% humidity/3 feet of elevation They would actually have to decrease the numbers. So I would have 9% more power today over there than here in the seat of the pants wich would be the equivelant of 44 ftlbs and 44 hp. California is good for something. LOL

Now if I was in Denver, CO today, I would only be making 87% of the standard thus losing 6%. So I gain more power driving to the coast than I lose going to Denver! It's 19 degrees, 90% humidity, and a mile high. I would lose approx 30 horse and ft lbs driving to Denver today. Little to cold for my taste.

Well one things for sure...no one can accuse you of not doing your home work!

:lol: