439 small block. peak hp at 7000 (778) peak tq at 5800. Timing locked at 32. Car weighs 2970 race ready w/t driver. 29.5 tall tire, 4.30 gear. Run was at Barona 1/8th mile, 1650 altitude, 2800 DA. 1.30 60ft, 5.96 @ 114.9 mph.



Launch rpm was 4800, converter flashed to 5790, shift light on tach set at 6800, peak 1-2 shift was 7650, peak 2-3 was 7170 rpm. Peak accel G was 3.0 at the hit (blue line).

This was the 8" converter that was designed for our W5 mill and we decided to run with it. Looks like it might be pretty close, maybe a little tight. I think the rpm ramp for the 1 and 2 gear looks ok, but going into drive it doesn't seem to climb as much as maybe I'd expect. Engine was dynoed with a QF 1050 and adapter mated to my intake. I'm currently running a Braswell 4825 4150 carb rated at 1000cfm so the above peak hp and tq are most likely off. I will eventually have a 4500 carb on it when I get an intake prepped, but for now.... this is how I roll. 18 passes on the combo and other than playing with launch rpm, and jetting up, I really haven't played with the tune much. The Racepack stuff is all new for me, but it's interesting and I hope to add on a few items in the future.

I've carefully examined the Rpm range during the run, the tightness of the converter and the final gear ratio, and determined it's perfect for a 200 shot from .3 into the run and for about 8 seconds!! You can thank me later!!

I would look into band adjustment. Your first shift has issues.

I think you accidentally have the longitudinal g-force on the graph instead of lateral (foward).

Your 3g's looks to be pitch rotation/wheelie, not forward motion.

Somethings up with the g-meter too, because it shouldn't climb when you put the car on the two step from the foot brake since the car isn't moving yet.

are you referring to the spike on the driveline rpm Leon? This was the only recording where that occurred. unfortunately time and $$ only allowed me to mount the tone ring on the slip yoke up near the trans. I was a bit worried about the fore/aft movement of the driveline messing with the input. It would be interesting to add a switch on the shifter and see where the rpm was when the shift was made compared to actual engine rpm. Necessary? probably not, but interesting none the less. I guess I never gave it much thought on where your shift light was compared to the actual engine rpm. Guess seeing light, pulling lever, mechanical operation of trans can take some serious time

I've also noted where the accel G has come up to .3-.4 when the t brake is applied. Was thinking electrical noise possibly? not sure. The racepack is mounted securely. I'll have to contact them about that. The line prior to the tbrake apply is reading zero.

that is probably the case. I've found in the few hits we've had, that on a hot track if I lower the 2 step rpm and hit the tires with the converter flash we can (so far) leave consistently. In Bakersfield it was cooler and we did a couple hits with the 2 step at 5400 and the front stayed down and the 60 was a 1.28.

I should have highlighted the Lateral G too. guess I could and post another pict up.

Jay, Getting kinda complicated aren't we. In the Mirada didn't you just turn the key and hit the power window switch!

Where is peak TQ? Looks to me like the converter could be loosened up a good bit. The slow accel graph into high gear shows the converter is to tight, likely pulling the motor down to far and it is not recovering well. Typical for an NA deal, thus why converter and gear selection is so critical running NA,especially in a motor not making a ton of torque. Although you pull out of the launch great, there is no discernible drop in wheelspeed at all, it is just slow to climb, another indication more gear or a looser converter will help accelerate the car. Also why you get the high G readings, no real wheelspeed at all.

You accel G meter is likely seeing some vibration due to the way it is mounted in the car. Likely nowhere near 3g's at launch. As eveidence from the numbers rising going on the brake, likely from the car rocking some.

Now get some O2's on there so we can really start tuning. IMO the accel G is one of the most important numbers there, along with wheelspeed. Would not worry about the driveshaft sensor much, if it were a leafspring car then yes but not on a ladder bar car. I don't think it will be an issue. We have done it MANY times with no issues.

Amazing how long it takes for YOU to react to the shiftlite and get the car in the next gear. Put a go pro in the car aimed at the shiftlite and shifter to see how long it takes for you to grab the gear. That would answer those questions. IMO that shifter is not helping any, put the other one in. But it is not unusual for you to need to set the light a few hundred RPM before you want it to shift.

I agree the 4.30 gear is the wrong tool for the job here.... and peak torque was at 5800 rpm (650 range). Interesting stuff for sure

I am not seeing 780ish horsepower at all with that time slip.
The ET and Mph at your weight are more indicative of about 700 horsepower at the flywheel.
I know my old combo( new owner now) has only very slightly slower incrementals at the1/8, weighs 200+ pounds more and makes 700 horse peak. 9.62@ 140 1/4, 114+@ 1/8.
I am sure you will get it figured out once you play with it more.

Well I'm not disappointed with the performance either. I'm just out to optimize/play with what I have. Running 9.5's in Vegas on a 92 degree day with a handful of passes on it, it can only get better. This combo is not set on kill, parts should stay happy a long time.

Jay has been faster than 9.62 at elevation in the heat. But what do I know. His combo is nowhere near optimized either as the data bears out. Converter and gearing are nowhere near optimal. Pretty sure if he wants to we could find ALOT of ET in there.

Some people just wanna rain on the parade.

The tune is half the fun keep up the good work

Mine made peak at 28 degrees and likes tO Be shifted 400 over peak power..

Bite me Al...... Really.

I didn't say he hadn't been faster than 9.62. I mentioned a 250 pound heavier combo that had, and made right at 700 horsepower, with very similar incrementals.
Just stating a fact, based on what the OP posted, nowhere near 780 horsepower is on tap.
Not raining on anyone's parade, just commenting and posting my opinion, which is what the poster asked for.
You have a nasty habit of shouting down certain peoples honest opinions. I have no idea why.

Doesn't bother me in the least, or I wouldn't have layed all the cards on the table.... I'm sure you just brought out what a few were thinking.. "wow, what an underachieving W8 mill". More of a post showing where were at, and where it will go from here with a properly matched torque converter and gear and some fuel sys changes. I'm also new at the "data" end of things and thought it would be of interest to show. If I cared or chose to hide behind sheets of paper with numbers on them I would. I love the combo and it's a blast to drive. If I want to get crazy with one of these deals maybe I'll make an ET chaser out of my other one. Honestly I was expecting 9.7's in Vegas in the heat. So far getting it to launch repeatedly in the heat has me excited as it was always a problem with the Mirada. I might be able to make this thing go rounds someday.... the delicate balance between improving what you have to go faster.... and keeping it consistent. Once the "heat" set it, which is really soon, I'll most likely pull the trans and send the converter to Lenny and have it tailored more to this combo, and decide what gear to go with.... I do have some 5.13's (that's a joke.... I do have them, but they would be about as wrong as the 4.30's that are in it....just on the other end of the spectrum).

Thanks Jay

I have zero doubt your combo will shine once it's sorted out.

"I am not seeing 780ish horsepower at all with that time slip."

Sure seems like from your first sentence you were poo pooing on someones combo to me. Maybe I am out in left field but would not be the first time.

Is it not ok to offer an opinion, be it good or bad? Thought that was kinda the norm when people ask for opinions on combinations.

I also said I am sure he will get it figured out.
If you make it a point to slam honest opinions, all you will be left with is either no comments, or politically correct ones that may overlook issues with something not running as good as it should. I have complimented hundreds of combo' s on here over the years.

Car would be tenths faster for sure at Milan or any east coast area track Imo.