[jimmy daniel]

When I come off the stop around 3.6 seconds it runs hard to the finish line. Anytime you pick up hp the mph goes up. Plus you can look at your Racepak and see where it picks up. I’m crossing the finish line at the same rpm at the same mph

[Stan Weiss]

Jimmy,
I like to play with simulations. How close is 9.383 @ 1000 foot to what you run. Based on simulated run of 10.901 @ 151.28 MPH.

Stan

[Scott Stoneburg]

Originally Posted by jimmy daniel

When I come off the stop around 3.6 seconds it runs hard to the finish line. Anytime you pick up hp the mph goes up. Plus you can look at your Racepak and see where it picks up. I’m crossing the finish line at the same rpm at the same mph

So what did the heads flow before BES this time?

[slowbird]

Curious what rpm you shift at and cam specs. Kind of surprised by the results

[ponjohn]

Maybe the converter is too loose after the head tune up?

[3fastgtos]

Originally Posted by jimmy daniel

Well results are back and I hate to say I saw no improvement. Ran Gainesville and I was still 10.90 @ 151. Same exact speed as last year. Car ran well and was very consistent and predictable but didn’t pick up anywhere. I jetted up and down and had time to try the timing at 32 and 34. I’m at a loss here.?

In the past whenever I’ve upped the hp and the car didn’t speed up it was the converter holding me back.
SD

[jimmy daniel]

Originally Posted by Stan Weiss

Jimmy,
I like to play with simulations. How close is 9.383 @ 1000 foot to what you run. Based on simulated run of 10.901 @ 151.28 MPH.

Stan

That’s pretty much the number

[jimmy daniel]

Originally Posted by Scott Stoneburg

So what did the heads flow before BES this time?

414 intake I don’t remember the exhaust right off

[cgeise]

what is the first number on the stop ?? is it air or electric and where are you shifting?? 3.6 seems like a lot of timer --

[jimmy daniel]

I’m .05 1st timer and shifting at .05. 60’s are 1.91. Rpm is 3950-4000. I had 3.60-3.70 in the second timer last year and the same thing this year. It’s like I never touched the motor. It runs exactly the same. I have the APD Maxspeed carb 1250. It’s air and the shifter is electric.

[johnta1]

Brakes dragging?



I didn't see your car there Friday?
Did you leave?

[Scott Stoneburg]

Try going back to the 1050 Carb.

[S/st 54]

1st of all imo this does not suck. You didn’t go backwards and that’s a bonus!

2cnd you had some high quality work performed and now have higher quality parts.

3rd I’ve been in this exact spot before. Long story short. I didn’t start seeing considerable gains until I started playing with torque converters.

With the current state of events. It looks like we might have some down time. So maybe some dyno time might be a good place to start. Find a happy place with fuel and timing. And maybe a few carb spacer changes that can answer your questions from another thread.
It does’t matter “how much it makes”,however, it does matter that you can take some tangible,visible information to a converter manufacturer and they can get you closer if you decide to make a change with converters.
I’m guessing a lot of good dyno operators could agree that it doesn’t matter if it’s a “happy dyno” or a “conservative dyno” your peak horsepower and torque will Occur at nearly the same rpm. And your curves will look very similar.

I’ve come to realize that dyno info is just as valuable as our racepak data.

The dyno time is fairly cheap and a lot quicker to get data considering It averages out for us to pay roughly $50-$75 per pass to go down the track at division races.

[cgeise]

Soooooo do you have a racepak on the car ?? if so what is the converter slip at the top end -- Logic would tell me you have some other issue going on - restricted air scoop -- rev limiter doing funny stuff -- something that when you find it will be an AHH HAAA moment.

[J.C.you]

Sounds like the motor liked the velocity over the increased airflow if rpm points and finish line rpm is the same. Time for more rpm?
If no dyno time after head work, pretty much a guess as to what the motor likes.

[jimmy daniel]

Originally Posted by cgeise

Soooooo do you have a racepak on the car ?? if so what is the converter slip at the top end -- Logic would tell me you have some other issue going on - restricted air scoop -- rev limiter doing funny stuff -- something that when you find it will be an AHH HAAA moment.

I have a Racepak on the car but I don’t have my laptop with me at the time. I DID however go to Gainesville with one of those clear lexan scoops on the car instead of my pro stock style scoop. The 2” tapered KVH spacer made it all sit up higher than I liked. I bought the Reher Morrison anti reversion 1/2 spacer and I’m mounting the old hood scoop back on. We’ll see what that does when my track opens. Thanks for all the ideas

[jimmy daniel]

Originally Posted by J.C.you

Sounds like the motor liked the velocity over the increased airflow if rpm points and finish line rpm is the same. Time for more rpm?
If no dyno time after head work, pretty much a guess as to what the motor likes.

JC you may be right and I hate it got finished so late I didn’t get it on a dyno. That always means a time consuming guessing game..,

[cgeise]

maybe I missed it but I never saw the trap rpm listed ??? I also have some concerns about the runner divider length in the plenum.

[jimmy daniel]

I’m 7500-7550 at the trap. Are you thinking the dividers should be cut back shorter?

[cgeise]

I know those in my intake were cut back -- its important to know the distance from the back of the intake valve to the opening in the intake at the plenum -- just a thought 7500 seems high for 150 mph what tire and what gear ???
just for compare my s/g car is 7900 at 174 --- 4.30 gear and 33in tire