What are the ET goals of this combo?

I have a 540 F1R but in a Racetech dragster with a 1.80 1st gear 4.10 rear gear. 28 degrees base timing and leave with 5 degrees launch retard bring it back within 1.5 secs launch at 4000 and how agressive the converter would be where i would look. I am currently running a Hughes SSX 10inch converter and the car repeats anywhere and any track conditions.

This message has been edited. Last edited by: topd1332,

Sorry Vince, forgot to mention you as well as a guy to guy.

Thanks again for all your help on Saturday at VMP.

the gear in tranny is for killing torque,gear in rear is for torque ,rpm and mph.if useing alot of gear and there is nothing wrong with it it means more timing retard.base timing at 26 in beginning.10 inch convertor for procharger from fti,abruzzi,greg slack or coan.there are some 4 link settigs i like to use,i would be interested in all of his numbers there.

Surprised by how much timing guys are suggesting to pull…. I haven’t run that small of a pc but with a f2 and my current f1x-12, in bad air I pull 2-4* and good air around 8*. That’s with a 1.80 and 3.89 rear gear. At the Topeka double I ran a 1.80 and 4.10 rear and lowered my launch 200 from normal and pulled 4* I think and went down the track easily, I was surprised. Ended up in the semis and final in the 2 races so it worked well. And I run Hoosiers and haven’t run Mickey’s in a long time…

My guess is suspension and definitely in the torque converter …

I have noticed when it comes to procharger set ups they seem to be all over the map...almost everyones combo and setups are very different

quote:

Originally posted by jenavet:

quote:

Trying to get as much info as I can for you all. It's an F1R, running 4.10 gears and I believe 1.80 first in trans. I believe he's running a whole lot more timing than anyone has suggested here

my opinion ... way too much rear gear and trans first gear...add wack timing numbers and who knows what drive ratio or pulley on there...she sounds vicious!!

^^^Agree..

Mine 26 base timing 3.90 rear gear, 1.69 low, 3200 launch, pull 10-12 degrees at launch ramp back in starting at 1 sec all in at 1,7.

.995 60, 4.3 1/8. 160mph

Mine was way violent with 4.10 and 1.8 low.

EDIT: Need to add I'm a roots guy. What are you guys with the Pro-charger doing with your boost?

Dave

I run 4.11 gear and 1.80 in trans. Launch at 3300. Forgot to add that in my initial post. Boost with current pulley setup sees 11, 12 on a really good day.

Appreciate all the input. I still forgot to ask how much boost he is running. He's running 36 degrees timing pulling 15 degrees at the hit and all back in by 1.8 seconds. It was running 4.50s @ 158 with a 1.05 60 when it would get down the track. A few weeks ago with the new shock and increasing the the timing drop from 15 to 8 it went 4.41 @ 160 with a 1.02 60.

converter and suspension..... no reason at all it shouldnt get off the starting line at 21* timing

Miller 247" bbc 600ci MFI
1.80 trans 4.10 gear big bubba at 7lbs
30 degree timing no retard
car 2215 lbs
3800 launch shift 7500
.997 60
4.165 1/8 169 mph
shift at 7000 goes 4.21 166mph
have over 500 runs same deal f3d-106 20 lbs
abruzzi convertor key to everthing best 60 with good air .961 stock strange shocks

I fought the same thing when using the jug on a 247” American. I wore out the fourlink/swing arm and bellhousing bolts changing bar angles and convertors - insisting on getting the little bubbas to work. The car was fine on motor (purpose built NOS engine and convertors) and would run high 50s to low 60s all day as a bracket car should. It took a few attempts, but ultimately when I was trying to make some local quick events, I would spray #28 jet in a fogger for three seconds, starting @ .50 out and the car would print 4.20 slips. Being a NOS rookie I didnt want to launch the carburetor and scoop into the stratosphere so I avoided pulling more than 3º at the hit and then another 7º during the hose. The one thing I concluded for myself, was that these cars (at least mine) could care less about anything but spring, shock and tire PSI….but that was with the little bubba and a weight handicapped car (lots of bling and a 295lb driver).

I settled in with dropping the spring down to a 200 lb spring and sent the shock back for a little rebound mod….after getting it back, I still ended up with an almost full soft bump and almost full stiff rebound to build some tire speed….it worked….Prior to the change you could see in slow-mo vid, the car would bite, slip, run over the tire and up in smoke. After the change, I believe if the conditions were right I could have turned the nos sooner, but in the conditions I was racing, I kept it conservative to assure some remedial chance of consistency.

Matrix, if you have your Penske shock dyno sheets available, PM them to me and I will attempt to identify the force vs velocity setting that worked for me – but also keep in mind I was close to 2k in weight, little bubba and 200 lb spring…..I would use the default bar setting that was most likely set up in the car when delivered. I really feel the popular 400 to 300 spring choice just does not allow the shock to do its job in controlling load transfer dynamics as its too busy countering the spring energy….dunno…

FWIW - I may have needed a different setting with the big bubba, but I was hell bent to at least use these little bubbas up before I took them off, I have since rolled over my Nos stuff to a door car….learning nuances all over again – what a joy.

This message has been edited. Last edited by: Jerry Kathe,

Diamond 245" dual suspended
582 F1R
1.80 trans
3.90 gear
Big Bubba 3197 4.8-5.0 lbs (3196 prior to the 3197)
Dual Penskes
Base timing 28
1685 with heavier dynatechs-no driver (1948 ready to go down)
3400 launch
Shift on time 1.7 (6850-6900)

Pulling 4 at release for about 3 secs
1.00 60
4.16 @ 172 best with above

Straight timing gets after it earlier going .960 (.957 best) with no bar or wheelies.
4.15

Matrix, The 4.10 is fine and also the 1.80's. Plenty are doing it with those now without issue.

My gut tells me the converter is wrong for the combo OR it has pulleys on it set on kill.
Was the converter built for this combo or someone just tried to use one they thought may work?

quote:

Originally posted by Jodie Jent:


Straight timing gets after it earlier going .960 (.957 best) with no bar or wheelies.
4.15

I have fought wheelies since I built my car.

I have changed rear gears, low gear, pulled serious timing, and added 100 lbs to front of car. Nothing I have done has stopped it from pulling the wheels and carrying them almost 60 ft. Sometimes further.

Dave

Here's a way out question: With so many running 1/8 mile now, wouldn't there be an advantage to a higher numerical gear ratio in second gear for accelerating the car?
4.10*1.80=7.38
4.36*1.69=7.36 SLR
With the same SLR, the front part of the track should be no different right? Should tighten up the converter on the back half.

David, you have a PM

quote:

Originally posted by David Covey:

I have fought wheelies since I built my car.

I have changed rear gears, low gear, pulled serious timing, and added 100 lbs to front of car. Nothing I have done has stopped it from pulling the wheels and carrying them almost 60 ft. Sometimes further.

Dave[/QUOTE]

Is this a hardtail car?

There are a number of reasons cars want to wheelie, no enough nose weight, converter, rear gear and tires all contribute to this but also the height of the motor in the car. The more power you have the lower it needs to be. If you have enough power that you need to manage it at the launch with a hardtail then a wheelie bar is your friend and it's not to prevent big wheelies! And, No matter what, the car needs to be balanced for the combo, if it' too light up front it will be impossible to tune without limping it off the starting line.

Joe I know you want to go faster. but Man for 2215 LBS. you are rolling You will find more it sounds like.

thats bracket tune theres 20k left to spin blower gotta have a reason lots of fun speed is

quote:

Originally posted by TOP38:


Is this a hardtail car?

There are a number of reasons cars want to wheelie, no enough nose weight, converter, rear gear and tires all contribute to this but also the height of the motor in the car. The more power you have the lower it needs to be. If you have enough power that you need to manage it at the launch with a hardtail then a wheelie bar is your friend and it's not to prevent big wheelies! And, No matter what, the car needs to be balanced for the combo, if it' too light up front it will be impossible to tune without limping it off the starting line.

No it is a Yanser 245in dual shock (Santhuf)
If you are not aware of them. It has the suspension (shocks/springs)right behind the driver. The engine, trans and diff are mounted like a hard tail. No driveshaft.
Engine and trans are in plane with the pinion using a coupler. So in order to get the engine lower in the car I would also have to rotate the pinion down.
I have 100 pounds in the front of the car 60 about 90 inches back which is as close as I can get to the front without making brackets, and 40 right at the tip of the chassis in front of the tires.

Dave