Not happy with my 1/4 mile time. I am thinking a new gear could help. Any help.
I have a Detroit locker with a 389 gear.
60 ft. > 1.78
1/4 mile >11.73 @ 119 mph,
Shifting @ 6000 rpms,
28" rear tire.
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Not happy with my 1/4 mile time. I am thinking a new gear could help. Any help.
I have a Detroit locker with a 389 gear.
60 ft. > 1.78
1/4 mile >11.73 @ 119 mph,
Shifting @ 6000 rpms,
28" rear tire.
what are you going thru the lights at rpm wise?
I was gonna ask the same thing, are you winding the last gear out.
What trany? if automatic what stall, what cam? what carb?
For that big block at 6000 rpm's I don't think your far off on the
gearing. I used to run a 410 gear in a dana 60 for the 1/4.
I was turning about 6000 rpm's too, But I had a 4000 stall.
I was turning low 11's but that 71 Charger was about 4200
pounds. What's your weight? 3800.
Are you hooking up or spinning the tires?
I can't say for sure of the rpm going threw the gate, but I will be sure to look next time., but I believe I am at 5500 rpm's.
The tranny is a C-6 reverse shifting.
3800 lbs is correct.
4200 stall
com cam #34-773-9
1050 Dominator
Got some spin, I am working on that too.
TedIII
If you're really at about 5500 through the traps a switch to 4.10:1 will help you... Can also tell by your mph vs ET that you could use some more gear. I would normally suggest a shorter tire since it's easier to change tires than gears unless it's a big change but seeing as how you're already at 28" I donn know if you want to go smaller... A 4.10 should get you a better short time and probably a few tenths off ET. But if you're trapping at 6000 you don't want any more gear
-Chris
Thanks,
Will run again this week, and be sure to check my rpm going threw the lights.
I am thinking a 410 will help but will known more after a few more runs.:HMMM:
You'll need to address your traction problem before worrying about anything else... If you can't hook now you'll never hook with a shorter gear... Good luck with your next runs
-Chris
Ted; I think you just have some tweeking to do.
I love your car, lots of class and style.
I went the ugly light way this time.
Here are some photos of my project.
http://www.flickr.com/photos/kurtvara/page2
Here is my buddies car.
http://loco4fomoco.com/1965_ford_falcon_ranchero.html
im having to go to 5:13's maybe even 5:38's
Quote:
Originally Posted by vara4
Looking good and going to be a nice ride I'm sure, your buddies ranchero is hot!:D:D
Those are some big gears, I personally didn't known you could get them that big!Quote:
Originally Posted by gassersrule_196
Agreed, i am going to adjust the front and rear shocks this week and the caltracs. I hope I get the weight transfer I am looking for.Quote:
Originally Posted by skids72
I've seen your car photo's Ted, Looks like you swapped out the front suspension.
What did you put in there to replace the old one?
I didn't see a sway bar, which is good so it help's the weight transfer
to the back better when you take off.
Are you running slick's or street tires?
Gassersrule is running a sbc 301 which can turn all kinds of RPM's you can get
alot bigger gears then 513. Most big blocks won't take the kind of RPM's the
small blocks do. Your building torque and HP at lower RPM's then he is.
Now I'm just guessing but I'd say he's turning 8,500 RPM's ask him.
That's why he's running that big gear!!!
I'm gonna run a 351 Cleveland in a 2,000 pound car that will only turn about
7,000 RPM's. I'm gonna run inbetween a 4.10 and a 4.56 gear to stay in my RPM range.
See Clevelands like to crack the blocks at 7,500 RPM's, but like your big block they are known for making lots of torque and HP. And we all know torque is what gets you rolling.
Kurt
Installed the mustang II front end kit. I was playing around with the tire pressure, I have slicks on, and I have adjusted the front shocks for 90 10 and I am changing the rear shocks to some 50 50s. According to my dyno sheet, I can run the rpms up to about 6500 without any problems.
A 2000 lb car with a 351, going to be an animal.
I hope so It's taken me long enough.
I just posted some new pictures of some of my progress.
But I have not got the pictures back of the frame in the car yet.
Kurt
http://www.flickr.com/photos/kurtvara/
Went to the track today, hooking petty good, just not squatting to the rear to help transfer weight. Going threw the lights at 5900 RPMs.
I am thinking that a 456 gear, and a trans brake would help.
Ted; Do you have any more pictures of your front end, after it is done.
Man I'm thinking you are already at 5900 rpm's, I think 456's is to much
if your redline is 6500 rpm's. I'm thinking 410 or 430 something in that area,
unless your not worried about going above 6500 rpm's.
600 rpm's ain't nothing when you start playing with them gears.
You won't be happy if you go to big, because you'll loose top end speed.
Not to mention if you go over your redline you could loose your motor.
I lost many big blocks going past my redlines, and it was never cheap.
Can you adjust those bars you've got hooked up to your leafsprings?
This way you can get the car to squat back some and help with your
weight transfer. A transbrake will really help as long as you are hooking
up hard. If your not hooking though, it will hurt you. Kurt
http://www.flickr.com/photos/kurtvara/
Back of the envelope all things equal (which they won't be since you'll be accelerating faster), a 4.56 gear will put you at least 6900 through the traps.... Likewise 4.33 will be about 6600 and 4.10 will be 6200...
New rpm= old rpm * new gear / old gear
Again this assumes the same rate of acceleration... In reality the new rpm will be higher... If I were you I would do 4.10 or 4.33 max if your motor can stand 6700-6800
Two cents,
Chris
You shift at 6000 you want to trap at 6000... 5900 is very close... Try 1" shorter tire and you'll be about 6100-6200. You might be better off leaving it alone.
Chris
Thanks Skids;I believe he said he was able to turn 6500 rpm's.
I thought he was gonna be over his redline.
I told him I was gonna run a 4.56 gear with my 351 cleveland.
My redline is at 7000 rpm's so I should do ok with that gear.
Kurt
http://www.flickr.com/photos/kurtvara/
Here are some things I change.
I took the Hoosier QuickTime Dot Tires off which were 325/50/15 with a height of 27.80 because the were not hooking, but I was going faster with a better et. (avg 119 mph) with a avg of 11.75 1/4 et.
Change the tires to so Hoosier 28-h x 10.5" w slick and my speed drop down to avg 115 and avg et of 11.90, but I am hooking better.
Also I change from VP C110 fuel with octane of 107, to Sunoco 110 with octane of 105.
I AM HOOKING BETTER WITH THE SLICKS BUT GOING SLOWER:(
Ok Ted; Your hooking now, that's a good thing.
Transbrake like you already said would be a good idea.
My next question might sound stupid but here it is.
What cam do you have and do you know the rpm range?
Or give me the info on your cam card, if you have it.
I'm thinking the your stall converter is hooking up before
your in your cams power band. The wheel spin before let
you build some rpm's and buy the time it hooked you where
probably in to the cams power band. You know what I mean.
You've got plenty of carb so that thing should be flying.
Did you have good reaction times compared to the others?
Ted if you can give me the full run down on your motor.
What are heads, if factory what year, compression all
the good stuff, if you know. Also do you have a shift
kit in your trany. Kurt