Took out the duster this weekend ran 11.475 with 4.11 gears running through the traps at 6200. Whould i be better to step up to a 456 gear change and hopefully run 7000 through the lights.And would that get me in the tens. I have a stroked 360 to 426 dyno at 628hp at 6800rpm i have a 28.5 tall tire
456 gears
- Thread starter 71dustya
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There's may help and most likely will.
Where did you shift on the run?
I have a 489 case, spool ,4.56 geared pumpkin.
Where did you shift on the run?
I have a 489 case, spool ,4.56 geared pumpkin.
daredevil
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sounds like you are leaving a lot on the table somewhere.whats the 60 foot?
60 foot was 1.63
What did it MPH? Do you know the car weight?
The 60' and ET are about right.
The 60' and ET are about right.
stroked 340
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That car should be running a LOT quicker then that, my 520 h.p. 416 puts my '70 duster in the 11.0's with only 3.91's...
Yep, that's why I asked the MPH question. If it's trapping at 128 with that e.t., it's all lost in the first 60'. My friends car goes 10.50/127, car weighs 3350 w/driver and 565hp. If it's not MPH in the high 120's it's not making 628 sitting in the car.
My guess is a converter that's too tight for the engine. It probably needs about/at least 5K stall to effectively use the powerband.
With 628 HP you should be trapping at 130 or so and be running 10.00 range.
116 at that weight is about 350-360 at the rear wheels
You're losing a ton through the driveline or the dyno was very happy.
What converter are you running and what's changed since the dyno to the car.
Is the fuel supply adequate. A holley black isn't going to feed that engine adequately.
i am running a mechanical pump from clay smith he said it plenty for my engine i ran a 125 on the g-tech matched it agianst the speedo. after that i sent my carb back to bigs and he leaned it out for me. i wonder if i should richen up the carb. i talked to jessie at bigs all he did was lean up the idol circuit and went down in jet size
Nope, the MPH shows what kind of power you're making. FWIW, My car weighs almost exactly the same and my stroker runs 117.8 in the 1/4...but I make nowhere near 620+ hp. My converter flashes to 5000 and I shift at 6000...if I shift at 6500 it runs the same number (strokers make big flat torque curves...and most are at max hp by 6000-6500.)
Without your combo, all I can do is guess...which is what I'm currently doing.
the motor is 360 stroked to 426 w-2 heads ported by ryan at shady dell flow 320 at 700 intake 217 exhaust run a indy -3 intake single plane 950 carb stage five from bigs. cam is roller dur @50 261/270 lift .630,1.5 rockers compression is 12.5 electric waterpump msd ignition timing is at 28 degrees locked out that is where we found the most power on the engine dyno the car is 70 duster, tranny is from john cope conveter is also from john cope stalls at 5200 dana rearend with 4.11 and 28.5 tall tires hope this helps
stroked 340
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Man,something is way off on your car i'm running those 11.0's @120 with a smaller carb,dual plane intake,and a much smaller hyd. cam and only a 3800 converter...
i know i just dont know where to look next wits end
Look at the fuel system first. Stock fuel tank or a cell. If stock, what's the sender line size?
Put a mechanical pressure gauge on it that you can see all through the run.
I wouldn't run anything less than a -8 or 3/8 line from the back, better yet a -10 or 1/2 line all the way up. 250gph pump minimum.
Something has changed drastically from the dyno session. Headers, carb... something. What's different from the dyno session?
Put a mechanical pressure gauge on it that you can see all through the run.
I wouldn't run anything less than a -8 or 3/8 line from the back, better yet a -10 or 1/2 line all the way up. 250gph pump minimum.
Something has changed drastically from the dyno session. Headers, carb... something. What's different from the dyno session?
timing set at 28 degrees?
are the w2 open or closed chamber heads....
28 degree does not seem to be enough....open chamber heads are going to want about 35 degrees total....
are the w2 open or closed chamber heads....
28 degree does not seem to be enough....open chamber heads are going to want about 35 degrees total....
i have 1/2 inch line all the way 1/2 inch pick-up. i have a fuel gauge and it doesnt fall below 7.5 pounds through out the run. only thing changed was the car was the idol circuit was leaned out by bigs and smaller jets were installed could that be it? almost half to be
What jetting was in it on the dyno and when you got it back from the carb guy?
The 28 sounds pretty low for timing. How did the pulling of timing effect the lower range numbers?
The 28 sounds pretty low for timing. How did the pulling of timing effect the lower range numbers?
jysnflem
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You might want to put it on a chassis dyno and see what your air fuel ratio is thru the entire power band. This would verify what horsepower you're putting to the ground and see if it adds up somewhere. Like everyone else said my car also runs mid 11's and it might be in the 450 to 500 hp range and with the driver it weighs 3260. I tried to scan a time slip for you to compare a 11.48 pass to a 11.10 pass but scanner not working so I typed them in for you. My car #102 did the slower pass of 11.487 very close to what you ran. Jayson
#202 #102
1.567 60ft 1.614
4.565 330ft 4.690
7.076 1/8ET 7.297
97.77 1/8mph 93.91
9.250 1000'ET 9.559
111.93 1000'mph 107.41
11.104 1/4ET 11.487
121.58 1/4mph 116.54
#202 #102
1.567 60ft 1.614
4.565 330ft 4.690
7.076 1/8ET 7.297
97.77 1/8mph 93.91
9.250 1000'ET 9.559
111.93 1000'mph 107.41
11.104 1/4ET 11.487
121.58 1/4mph 116.54
I'm going to say timing and jets.
Go to a test and tune night at you local drag strip and start tuning for maximum trap speed...forget the ET for now. Make a baseline pass, then bump the timing up to 34° and make a pass. If it picks up a big chunk then try 36 (I bet it will like 34-38°). Next jet it up 2 sizes until you MPH drops, then back up one size and you should have the jetting dialed. After that, then start messing with launch rpm and begin to get a handle on that 60' time...one step at a time, but get the motor making the power first before you start worrying about ET.
FWIW, last fall my old motor picked up half a second and 6 MPH when I took it from my high altitude nitrous tune (28° timing) to low altitude All motor tune (35° timing and jetted up 4 sizes).
Go to a test and tune night at you local drag strip and start tuning for maximum trap speed...forget the ET for now. Make a baseline pass, then bump the timing up to 34° and make a pass. If it picks up a big chunk then try 36 (I bet it will like 34-38°). Next jet it up 2 sizes until you MPH drops, then back up one size and you should have the jetting dialed. After that, then start messing with launch rpm and begin to get a handle on that 60' time...one step at a time, but get the motor making the power first before you start worrying about ET.
FWIW, last fall my old motor picked up half a second and 6 MPH when I took it from my high altitude nitrous tune (28° timing) to low altitude All motor tune (35° timing and jetted up 4 sizes).
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