Guess ET for 318 ? With slicks ???

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T67POWER

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I went to the track and ran my 318 barracuda.
Gave it half pedal out of the hole and then rolled into it.
Result was a 14.38 @ 94.37 mph.
Being more aggressive with the pedal at the starting line did not work to well as you can see.
Car went 15.82 \ 15.39 \15.18 smoking the tires

(The car has a radial tire on it now and a 7 1/4 rear with 3.91 gears.)

I am installing a 8 3/4 with 2.94 gears, and will also try a set of 4.56 gears.
((((((( I will be using slicks with the new rear. ))))))

EVERYTHING ELSE WILL BE THE SAME SET UP>>>>>
318 REBUILD PARTS:1967 318 BLOCK
KEITH BLACK STOCK SILVO- LITE 9.1 PISTONS (1266)
STOCK 920 1967 HEADS (1.78/1.50 VALVES)
PAW VS150 VALVE SPRINGS PAW SUPER STOCK CAM .453 LIFT
225 @ 50 DURATION
108 LSA EDELBROCK PERFORMER INTAKE WITH 1/2 INCH FOUR HOLE SPACER
750 HOLLEY 4150 MECHANICAL SECONDARY CARB
904 TRANS.
CHEETAH VALVE BODY(17676)
3000 DYNAMIC CONVERTER

my car weight was 3150 lbs.
3330 lbs with me in the car.

:idea1: GUESS NEW ET FOR CAR WITH A:2.94 GEARS

:-k GUESS NEW ET FOR CAR WITH B:4.56 GEARS

P.S. ((( I WILL BE USING A 28 INCH TALL SLICK ))) good luck :thumrigh:
 
2.94s and a 28" slick will be bad. If a 15.1 was your best before I bet the tall tire and bad gears will put you in the 16s.

Edit…. I just saw you ran a best of 14.38. My new guess is a mid 15 with the 2.94s.
 
Don't forget to a guess for each set of gears i will be running.

Guess ET for the 2.94 gear set, and also guess the ET for the 4.56 gear set.

This is the perfect car to do this test with because it already has some track time, and i will be trying one change at a time.
This should be a good test for gearing a car for the track and will also help people with similar combinations go faster.

HELPFUL FACT>>>>>>>>>>>>
I WILL BE RUNNING THE 2.94 GEARS AS A TWO SPEED, USING ONLY 1ST AND 2ND GEAR IN THE QUARTER MILE.
 
Call me crazy but I think you will be in the mid 15s with the 2.94s and the 4.56s.

Im pulling this out of my butt, but I would bet $1 on it.
 
TO 1968formulaS340,
I won't call you crazy,thats what you think, and thats cool.
Buy the way, nice color paint on the cuda.
 
Call me crazy but I think you will be in the mid 15s with the 2.94s and the 4.56s.

Im pulling this out of my butt, but I would bet $1 on it.

Hahaha I like it, you think he will go slower with better tires regardless of the gears... haha

My guess is close to 14.00, maybe 14.1 and thats with either gear ratio.
 
Put a rear suspension in it; gearing- just all over the place. You will never find the happy spot.
 
I went to the track and ran my 318 barracuda.
Gave it half pedal out of the hole and then rolled into it.
Result was a 14.38 @ 94.37 mph.
Being more aggressive with the pedal at the starting line did not work to well as you can see.
Car went 15.82 \ 15.39 \15.18 smoking the tires

(The car has a radial tire on it now and a 7 1/4 rear with 3.91 gears.)

I am installing a 8 3/4 with 2.94 gears, and will also try a set of 4.56 gears.
((((((( I will be using slicks with the new rear. ))))))

EVERYTHING ELSE WILL BE THE SAME SET UP>>>>>
318 REBUILD PARTS:1967 318 BLOCK
KEITH BLACK STOCK SILVO- LITE 9.1 PISTONS (1266)
STOCK 920 1967 HEADS (1.78/1.50 VALVES)
PAW VS150 VALVE SPRINGS PAW SUPER STOCK CAM .453 LIFT
225 @ 50 DURATION
108 LSA EDELBROCK PERFORMER INTAKE WITH 1/2 INCH FOUR HOLE SPACER
750 HOLLEY 4150 MECHANICAL SECONDARY CARB
904 TRANS.
CHEETAH VALVE BODY(17676)
3000 DYNAMIC CONVERTER

my car weight was 3150 lbs.
3330 lbs with me in the car.

:idea1: GUESS NEW ET FOR CAR WITH A:2.94 GEARS

:-k GUESS NEW ET FOR CAR WITH B:4.56 GEARS

P.S. ((( I WILL BE USING A 28 INCH TALL SLICK ))) good luck :thumrigh:

I'll bet you'll be in the 13s hooking & the 4.56s.
 
Wow, 2.94 and a 4.56? What`s going on here? Are these just gears that you`re able to get your hands on? Neither gear seems a good match for your combo. With that 2.94 gear you`ll probably never get into 3rd gear and with the 4.56 you`ll probably run out of engine. The 3.91 you have now sounds like a better gear than either of the other two. With the 2.94 gear I would guess an ET in the upper 15`s, with the 4.56, about what you`re presently running , maybe a smidgeon faster/slower than your best 14.38.
 
Wow, 2.94 and a 4.56? What`s going on here? Are these just gears that you`re able to get your hands on? Neither gear seems a good match for your combo. With that 2.94 gear you`ll probably never get into 3rd gear and with the 4.56 you`ll probably run out of engine. The 3.91 you have now sounds like a better gear than either of the other two. With the 2.94 gear I would guess an ET in the upper 15`s, with the 4.56, about what you`re presently running , maybe a smidgeon faster/slower than your best 14.38.
I'am with longgone on this one.
 
I'll step out on a limb here and say...13.98 with the 4.56 gears and 14.98 with the tall gears....sure, why not.:toothy10:
 
I'll step out on a limb here and say...13.98 with the 4.56 gears and 14.98 with the tall gears....sure, why not.:toothy10:

Thats what i'm thinking too, he already went 14.3s on street tires & easing on it from the gate, his MPH at 94 should be enough for high 13s with good 60ft. times, that will be better achieved with 4.56 gears, i'm sure theres a couple more MPH left in it, its a SB, they like alittle more gear, i'll agree a 3.91s or 4.11 would be about all thats needed for his combo, but he is going to run a 28" tire, this will be better suited for that 4.56, most run 4.11s with a 26 or 27", so he's close.
 
13.9 with 4.56 gears and slicks and good driving, 2.94 gears. . . stay on the highway and drive right past the place :-D why not try slicks with the 3.91 rear end? That would get your best ET I bet.
 
13.9 with 4.56 gears and slicks and good driving, 2.94 gears. . . stay on the highway and drive right past the place :-D why not try slicks with the 3.91 rear end? That would get your best ET I bet.

The 3.91s are in a 7 1/4. Slicks, 3.91 and a 7 1/4 = I could beat him walking.
 
14.38 is a really good time with that converter and those heads. In my opinion it will be no faster with the 4.56 gears as it,ll run outta motor at the 1000 ft. and I wouldnt waste my time with the 2.94. Why not trade the 4.56 for a set of 3.73 or 3.91 since the 3.91s seem to work so well. What rpms were you turning thru the traps on the 14.38 pass? Where does the rpm band max out?
 
I shifted the motor at 6000 in first and second gear and went threw the traps at about 5400 rpm.
The 3.91 gears are perfect for the combination i have ,if i run a 26 inch tall tire.
The 7 1/4 rear won't handle slicks though.
The 8 3/4 has a 2.94 gear set in it.
I also have a set of 4.56 gears in a 489 case with welded spider gears.
I will be buying a spool for the 4.56 gears, and will run those too.
I will be using a 28 inch tall tire, and when used with 4.56 gears will add only about 400 rpms to my trap rpm.
If i ran 4.56 gears with a 26 inch tall tire it would be to much gear for the motors power band.
At 5800 it will be just past my peak horse power and will run the fastest due to my 60 foot short time being improved ,and it will give me more mph.
The 2.94 gears will be slower but the cam and converter are perfect for both gear sets.

The bigger tire will help with traction with the 4.56 gears.

The bigger tire will help in a different way with the 2.94 gears, since i will only be using 1st and 2nd gear,so i need to keep the rpm's down and this will do just that.
When racing with the 2.94's, i will shift at 6200 and go threw the traps a little over 6000 rpms.

Thank you for your reply's and we will see who's the closest on the ET guess.

This might surprise some people in the end, at what you can get out of a set of highway gears when run as a two speed, and also when you rev a pretty much stock small block up ,and keep it wound up the hole way threw the traps.8)
 
I shifted the motor at 6000 in first and second gear and went threw the traps at about 5400 rpm.
The 3.91 gears are perfect for the combination i have ,if i run a 26 inch tall tire.
The 7 1/4 rear won't handle slicks though.
The 8 3/4 has a 2.94 gear set in it.
I also have a set of 4.56 gears in a 489 case with welded spider gears.
I will be buying a spool for the 4.56 gears, and will run those too.
I will be using a 28 inch tall tire, and when used with 4.56 gears will add only about 400 rpms to my trap rpm.
If i ran 4.56 gears with a 26 inch tall tire it would be to much gear for the motors power band.
At 5800 it will be just past my peak horse power and will run the fastest due to my 60 foot short time being improved ,and it will give me more mph.
The 2.94 gears will be slower but the cam and converter are perfect for both gear sets.

The bigger tire will help with traction with the 4.56 gears.

The bigger tire will help in a different way with the 2.94 gears, since i will only be using 1st and 2nd gear,so i need to keep the rpm's down and this will do just that.
When racing with the 2.94's, i will shift at 6200 and go threw the traps a little over 6000 rpms.

Thank you for your reply's and we will see who's the closest on the ET guess.

This might surprise some people in the end, at what you can get out of a set of highway gears when run as a two speed, and also when you rev a pretty much stock small block up and keep it wound up the hole way threw the traps.8)

I like the way you think 8)
 
I dont get your 2 speed concept because your trans is geared as a 3 speed. I bracket raced a teen for years and it needed the gear.
 
daredevil,
When you have a gear set 2.94 or less and run at least a 28 inch tall tire, you don't use third gear.
The hole idea is to have the car go over the finish line, with the motor pulling it's highest rpm and making the most power.

When people run at the drag strip, they hit third gear and it's like pulling
the carpet out from under the car and it slows the et down.

If i had to compare it to something else it's like running a chevy power glide in your car.

My coronet with a 360 and a .474 purple shaft went 13.86 at 98 mph doing this, and i ran a 235/75/15 inch radial tire.
On a hot day it would go 14.00 flat.
The cuda has a smaller cam but it pulls also to 6000 rpm's
It's all about the tire size and the gears.
You have to run a tall tire to get traction and effectively reduce the gear ratio even more so you can run the car as a two speed.

I put 4.10's in the coronet with a slick and guess what it ran???????
13.65 at 99 mph on a hot day and 13.46 or so on a cool day.
THIS IMPROVED MY SHORT TIME BY 2 TENTH'S OF A SECOND
AND IMPROVED MY OVER ALL ET BY 4 TENTHS OF A SECOND. :burnout:
 
I think you`ll see the most improvement in your ET`s once you get the rear end set up with the proper spring clamps, long shocks, pinion snubber, proper gear, and tire type/size/pressure. If you`re having to pedal the car at launch you`re losing a lot of time, I think you`ll see several tenths (if not more) with a full throttle launch.
 
For my 2 cents, I'm no race expert but did do a little bracket racing when I was younger and couldn't afford good gears so I'm gonna guess that with the tall gears it'll bog so bad at the line that high 15's will be the best to expect. The 4:56 is a tougher call, given the taller tires I'm gonna say you might break into the 13's. BTW, who's collecting the bet money on this thing LOL. Kev
 
I will post what i think it will run before i go to the track, and then post the time slips.
Keep the guess's coming
This will turn out to be a cool thread that everyone can use for info, and it will be a lot of fun to see who win's.
 
With 2.94s and 28" slicks - 15.30s
With 4.56s and 28" slicks - 14.00s

Calculators say about 260 crankshaft hp and potential of mid to high 13s as it sits. But like Longgone said... IMO it's a mismatch from the carb to the rear tires but those are fun to play with and see what you can do.
 
T67, i was told by most on here & moparts that my combo would NOT see 12s, it just wasn't in the math lol, i just went 12.58 last night if that tells you anything!!
 
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