Break in the 12s

[mopar6976]

Hi guys do you think i could be a member of the the "12 second club". I know it might seem boring to you but i would like to know if it is possible?! The car is a 69 Road Runner 440 with 10.5 compression M1 intake manifold, eddy heads fully balanced 850 quickfuel-carb, A-833 tranny, 3.91 diff, msd ignition, comp cam, SS-springs and so on....... The weight is pretty heavy because of the driver and i am shifting gears a little slower than Ronnie Sox.
Thanks for your help and greetings from Germany.
Arne

 

[wedge5]

Don't know what size cam and if you are using slicks? But everything else seems to be in order for a "12 Second Club" run.

 

[SUPERSTOCKRACER]

i'd lie to see some 4.10's for gears. but i think your right there.just make sure you got a nice quality new clutch.

 

[mopar6976]

The clutch is a centerforce dual friction.

 

[SUPERSTOCKRACER]

The clutch is a centerforce dual friction.

Thats the clutch I use, They are excellant. Go out there let us know how you do. Good luck!

 

[herschel]

What kinda fuel pump are you using, and are you getting plenty of fuel pressure top end?

 

[mopar6976]

Yes i will use slicks! I have a stock fuel pump mounted, but i am going to replace it by a mechanical aftermarket fuelpump but i am not sure about the psi range which pump would you recommend? I use my car for the street as well as for the strip. What do you guys think about 1.6 ratio rockers? I think the edelbrock heads are good for 600 lift?! The Race is in August and i want my car to be well prepared for that event. Sometimes i wish i could live USA because there is much more dragracing going on and you got more tracks and events to test your car etc.

 

[HEMI-ITIS]

Well Arnie,you will have to practice and learn how to "power shift" that bad boy to push it into the 12's.Also check the the z-bar mounts and bushings for flex and movement.If it has too much flex,it will prevent speed shifting resulting in a missed gear:munky2:

 

[wedge5]

You have not told us what size(lift) cam you are running. Check your cam card to see what the cam lift would be with 1.6 rockers. If it is around .580 with 1.6 then you are good. The reason I say .580 and not .600 is that I would rather have some leway. Better safe than sorry.

Carter has a Hi-Output mech pump 8.5 psi. Not sure if 8.5 psi is to much for normal street driving. Edelbrock,Holley also have a hi-output pump so I guess it comes down to preference.

What kind of shocks are you using? Size slicks? Do you have battery relocated to trunk? You could add a torq strap to the motor,poly motor and trans mounts. When you run it at the track you could remove the air cleaner or flip the lid. Run 93 octane but you could also mix 100 octane with 93 to get an average of 96.5. You wont need anything more than that.

I realize this is a street driven car so I am trying to give you a few things to consider and keep it streetable. Once you hit the 12's it will be on to the 11's then you will want to 10's. I said I would be good with the 12's but everyone was going faster and I wanted to be fast also. It never ends

Don't forget the driveshaft safety loop. The tech guys will check it.

 

[mopar6976]

I believe you and i think improving your et is like a drug. My cam has 106 center, intake lift is 507, exhaust lift is 510, dur 240 244 @050, lobe 110 hydraulic comp cam. I have competition engineering dragshocks and the (semi)slicks 275/60 are MT ET street radial or hoosier slicks if the mickeys do not work. The battery is located in the stock under hood position. The drivshaftloops will be installed and some heavy duty u joints too.

 

[383man]

That should go easy 12's. Just use about a 28 x 9 slick as that will work fine with the 3.91's and a 440. Sure 4.10's might be better but not by all that much. I would consider putting a line lock on it if you don't have one. That makes it so much easier to heat the slicks up. Good luck and make sure you let us know how it goes. Ron

 

[67 B-body]

I ran mid 12's with a 69 road runner / 440 / mopar 292 .509 hyd cam / 4.10 gears / automatic 727 w 10" convertor / Cheeta reverse shift manual valve body / Holley carb / 9" cheater slicks.
Not much going on with the car for exotic performance mods, just basic off the shelf stuff thrown together on a tight budget!

 

[poppaj]

You have not told us what size(lift) cam you are running. Check your cam card to see what the cam lift would be with 1.6 rockers. If it is around .580 with 1.6 then you are good. The reason I say .580 and not .600 is that I would rather have some leway. Better safe than sorry.

Carter has a Hi-Output mech pump 8.5 psi. Not sure if 8.5 psi is to much for normal street driving. Edelbrock,Holley also have a hi-output pump so I guess it comes down to preference.

What kind of shocks are you using? Size slicks? Do you have battery relocated to trunk? You could add a torq strap to the motor,poly motor and trans mounts. When you run it at the track you could remove the air cleaner or flip the lid. Run 93 octane but you could also mix 100 octane with 93 to get an average of 96.5. You wont need anything more than that.

I realize this is a street driven car so I am trying to give you a few things to consider and keep it streetable. Once you hit the 12's it will be on to the 11's then you will want to 10's. I said I would be good with the 12's but everyone was going faster and I wanted to be fast also. It never ends

Don't forget the driveshaft safety loop. The tech guys will check it.

8.5 psi way to much pressure, put a regulator on and set to 6-6.5 psi.

 

[wedge5]

Figured that 8.5 was high.
Why wouldn't you just put on a pre-set 6.5 mech pump on and not mess with the reg. What does a stock pump putout?

 

[67 B-body]

Figured that 8.5 was high.
Why wouldn't you just put on a pre-set 6.5 mech pump on and not mess with the reg. What does a stock pump putout?

I think that what you'll find is "volume" goes hand in hand with "PSI".
What you trying to do is have a supply "volume" that is capable of keeping up with your engine at it's peak RPM, and not let the fuel level drop in you float bowls. To do this you wind up having a higher PSI with an increase in volume as a result.

 

[Meep-Meep]

I'm running a Holley mech pump on a warmed up 440 and it's between 5 and 7.5 PSI. No issues at all and no regulator required. Plus, all the fuel the engine will ever see enters through two .090" diameter holes (needle and seat). 7.5 PSI is required with aftermarket Holley's and Carters, or I should say Edelbrocks, to maintain the proper fuel level in the bowl under all conditions. For moderate performance use the stock 5/16" line to the tank will be just fine.

 

[mopar6976]

Thank you guys for the the support and for the help..... Can´t wait to install all those goodies and to put it on the strip in August.

 

[Patrick]

With what you have now plus an adjustable pinon snubber, 11" wide 27" tall Firestone N9 compound slicks, battery behind right rear wheel in trunk. You should go into high 11's. You can run the slicks on 15X10 5" backspace wheels. 28" is to tall for your gear. Rubber on pavement is where the real gear ratio is. 3:91 gear, 27" tire is about 3:78 on the ground, 3:91 gear 28" tire is about 3:44 on the ground.

 

[mopar6976]

Is there so much difference if you have the battery is located in the trunk? I don`t wanna cut the car and i would like to keep it pretty stock. What do you think about caltracs instead of a pinion snubber or does it seem to you like a waste of money?

 

[wedge5]

Battery in the trunk is for two reasons. 1: Revome weight from the front end and 2: Put extra weight over the right rear tire.
There is no cutting up the car involved. But battery box in trunk;check NHRA rule book for proper installation. Heck you could put the cut off push/pull switch under the bumper.

You could use the stock leafs and add the Cal-trac traction bars to them. Don't use dragshocks on the street. Could make car react funny under hard breaking (if you had to). There are shocks for street driving that also would help transfer weight when you went to the track. Heck, I think Cal-Trac has a 9 way adj. shock also.

They Don't make Firestone slick anymore but if you are looking for a tire M/T makes a 28x11.5x15 which measures 27.6x11.1 section and 8.6 tread on a 8" rim. Run them on a 15x8 w/ 4.5 backspacing.