1/4 mile ET guesses

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Walker434

Walker434

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Ok so I took my 71 dart 318 to the track last fall after I had just purchased it. Original 318/904/7.25 combo. I don't know the internal specs of the engine but it's got headers to 2.5 flowmasters, original heads (not sure of compression or if any work has been done to heads), a weiand stealth intake and a carter AFB 625 carb. I ran a 15.53 at 88 mph and couldn't get it to hook (open 2.76 gears and old cookie cutter tires).

Since then I have swapped out the 7.25 for an 8.75 with 3.91 sure grip. Installed offset SS springs with 50/50 drag shocks and put 275/60/15 MT drag radials on. I also swapped the front wheels and tires for skinny centerlines. Everything else is exactly the same. So now it hooks VERY WELL. I can lauch perfectly at 2500 with little to no tire spin.

I am going back to the track this weekend for Test and Tune. Any guesses on my new ET?

Here is a pic of the new look by the way. It's a fixer upper.
 

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awesome! I like the look! not sure what it'll run but have fun and keep us posted!
 
With a taller tire in rear(other than old cookie cutters)I,ll say 15.00.You might wanna look into 3 inch studs at the rear with sticky tires.What you have would,nt pass tech here.Good luck.
 
I will say 14.59 :glasses7:

BTW, your car looks badda$$ with the new stance and tires :finga: :D :prayer:
 
15.28 @ 87MPH

I bet if you weighed the wheels and tires you took off and compared that to the total weight of the wheels and tires you put on you will find that it is a wash.

28" tall tires with a 3.91 = 26" tire and a 3.55 gear

I bet the original tires on the back were closer to 25", so the original 2.76 was closer to a 2.85 gear on a 26" tire.

The overall gear change was from 2.85 to 3.55 or .70 ratio difference.

Guessing here:
60ft = 2.08
1/8mi = 9.73
1/4 mi = 15.28
1/4 MPH = 87
 
Thanks for all the compliments on the looks! I hate that it looks fast and currently is a dog but I am prepping for when I drop in a 408. I have a 1978 360 block but am now thinking about trying to find a late 80s early 90s roller. I realize the tall tire makes the 3.91 more like a 3.55 but I knew I would need the meats when I have the 408 torque monster.

I would be really happy with anything under 15 flat we will see. I'll let you guys know who got the closest when I get back.

Another pic of the new stance. It's driving my wife crazy that I'm spending all the money on go fast not look pretty :finga:
 

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I put longer wheel studs on the back when I had the axles out.... I was really suprised when my acorn nuts still worked. Do they just require the studs to show or do they actually require them to be 3"?
 
Walker434 said:
I put longer wheel studs on the back when I had the axles out.... I was really suprised when my acorn nuts still worked. Do they just require the studs to show or do they actually require them to be 3"?
Click to expand...

They do not have to be 3" studs. The rule book states the stud must be long enough to engage the threaded hex portion of the nut by at least as much as the diameter of the stud. In other words a 1/2" stud must thread at least a half inch into the hex portion of the nut. Generally not an issue with steel wheels but check your fronts.

And I'll guess 14.90-15.00.
 
99% of tracks will not even look at this.. Hell new corvettes run 12's and they do not have them and I have never seen any new car stopped at tech.

I will go 15.05 You are going to be close to that 14.99.. good luck with it..
 
AND THE WINNER IS...... Sledger46. I just couldn't break into the 14s :banghead:

The best run was 15.22 @ 86 MPH. I will attach the ET slip from last fall when the car was as purchased and then this weekends ET slip along with some pics. I would post a video but can't figure out how yet. The one picture shows me pulling the camaro out of the hole but my lead didn't last long! He ended up running 13.1.
 

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Glad I kept my money in my wallet on this one....lol.

3 tenths is 3 tenths :thumleft:, but where did the mph go? My only guess there is, that the new gear/tire combo has you trapping at the low end of 3rd gear instead of the higher end of 2nd with the old combo.
 
best way to post video is to upload it to youtube...then copy and paste link here...
 
As oldmanrick said, 3 tenths is 3 tenths. Hell, I just spent 2 grand for 3 tenths!! Congrats! and welcome to the sickness.
 
I like the look, Just my thought, find a 500 cfm carb see if that makes a difference. This comes from my experience with the 318 for what thats worth. Good Luck.
 
OldmanRick said:
Glad I kept my money in my wallet on this one....lol.

3 tenths is 3 tenths :thumleft:, but where did the mph go? My only guess there is, that the new gear/tire combo has you trapping at the low end of 3rd gear instead of the higher end of 2nd with the old combo.
Click to expand...

I am guessing you're right. With the old combo I was at the top of 2nd crossing the traps, now I am at the bottom of 3rd. The best run was shifting at 5500. One run I tried running up to 6 grand in 2nd but it spuddered a little.

Does anyone else think I would benefit from less CFM? Couldn't I change the jets in my current AFB? It does smell a little rich.

Hopefully this little 318 won't be in the Dart much longer but if it is I would love to break into the 14s.
 
Sputtering is probably valve float. Back in the day, I bought a new 70 Duster, 318, manual 3 speed, open 3.23, f70 14 tires.

Same thing, mid 15's. Installed a holley 500 sbbl. So rich, took a month of learning how to tune a holley, still too much carb for the engine, but it stopped burning my eyes.

Then old school traction bars, and played with them until both tires spun.

Then heavier valve springs, to stop the float.

Then is was a 14.95 car.
 
Walker434 said:
I am guessing you're right. With the old combo I was at the top of 2nd crossing the traps, now I am at the bottom of 3rd. The best run was shifting at 5500. One run I tried running up to 6 grand in 2nd but it spuddered a little.

Does anyone else think I would benefit from less CFM? Couldn't I change the jets in my current AFB? It does smell a little rich.

Hopefully this little 318 won't be in the Dart much longer but if it is I would love to break into the 14s.
Click to expand...

One thing I know is a mild 318 will never be a top end powerhouse....lol.

I hate to see you spend money on pieces that wont work with your upcoming engine, but at this point, I don't know if the're enough tweaks to take off 2 tenths.....

As far as the carb, I'd just play with what you have. "Green" has a point about the valve springs.....If you think it will still pull to 6k and you have a fairly low lift cam, you could probably shim the springs and get a few more rpm from them.

Other thoughts would be......

The mismatch between the intake ports on the Stealth and the stock head ports.
Opening the headers.
Front tire pressure up to 45ish....track only.
Best pump octane and bumping the timing a few degrees at a time.
If your ignition system is strong, good wires, powerful coil.....you can open the spark plug gaps .005/.010....At the track.
Taking out any easily removable weight.
Staging as shallow as possible.
Varying launch technique....meaning to try just off idle to flash the converter, and also, power braking as hard as possible. Some cars work better one way or the other.

I'm sure i'm forgetting some, but a few things to think about before spending on a cam, converter, etc.
 
OldmanRick said:
One thing I know is a mild 318 will never be a top end powerhouse....lol.

I hate to see you spend money on pieces that wont work with your upcoming engine, but at this point, I don't know if the're enough tweaks to take off 2 tenths.....

As far as the carb, I'd just play with what you have. "Green" has a point about the valve springs.....If you think it will still pull to 6k and you have a fairly low lift cam, you could probably shim the springs and get a few more rpm from them.

Other thoughts would be......

The mismatch between the intake ports on the Stealth and the stock head ports.
Opening the headers.
Front tire pressure up to 45ish....track only.
Best pump octane and bumping the timing a few degrees at a time.
Taking out any easily removable weight.
Staging as shallow as possible.
Varying launch technique....meaning to try just off idle to flash the converter, and also, power braking as hard as possible. Some cars work better one way or the other.

I'm sure i'm forgetting some, but a few things to think about before spending on a cam, converter, etc.
Click to expand...

Good stuff.
 
Thanks Oldmanrick for the advice. I don't plan on spending a bunch of money on this 318 since a swap is in the near future. Although, it does still have the stock points ignition so I think I could convert to electronic and see some benefit with the 318 then still use it on the big engine when it goes in. I wish I would have tried leaving the line at idle once on Saturday. I was leaving at 2500 everytime which is as high as I can foot brake my converter.
 
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