Page 3 of 4

Posted: Sun Jul 01, 12 12:08 am
by Cannonball
Pete wrote:
Cannonball wrote: ............... but at very low 10's on an "A" Body I think you are starting to push your luck.........ask Mags Bailey on his views.........
9.4,s fast enough on stock suspension pete ;)

Yep, that would be an "E" Body and if truth be told that was getting on the ragged edge ;) Fair play for the time though :thumbright:
i think an a body correctly set up and sensible tire height would drive much like an e body it has a longer wheelbase after all and i know for a fact on the street the larger b body deffo out drives an ebody,,,,,

Posted: Sun Jul 01, 12 12:22 am
by Pete
Another factor that comes into play in my opinion is the 10.5" Tyre widths.

Yes, I know they go ballistic in the States but if you come down in tyre height it not only affects the gearing (which can be compensated) but also the contact patch on the ground. I think this is another big factor in terms of hook up but also stability......

Posted: Sun Jul 01, 12 1:16 am
by Les Szabo
Going for lower tyres with less gearing with the same hp will result in a slower car unless your already overring at the traps.
You need to run your car as low as you can, with tubs and a tall tyre and low gear for best 60's, ET and stability. Its an increase in HP that will dictate a drop in gearing with a given tyre height.
The '69 ran 4.88 gears and 32's, and it was fine on the motor at around 10.7's and 6400 at the traps. Put 175hp through it at around 650hp and it well maxed out at 7000 with 6-pk rods, and would've needed a drop to 4.56 or 4.30 gears where it probably would've run quicker than 9.96.....Ideal scenario would've been 5.13 gears and Ally rods, lighter pistons and turn 7500rpm+.

Posted: Sun Jul 01, 12 2:44 am
by pete walton
The Nostalgia SuperStock class in the states run big moters with no power adders ,nearly all the cars run caltracs,most run deep into the 9s.... Must admit that most of the cars in that class are the bigger models not a bods

Posted: Sun Jul 01, 12 12:35 pm
by Cannonball
Les Szabo wrote:Going for lower tyres with less gearing with the same hp will result in a slower car unless your already overring at the traps.
You need to run your car as low as you can, with tubs and a tall tyre and low gear for best 60's, ET and stability. Its an increase in HP that will dictate a drop in gearing with a given tyre height.
The '69 ran 4.88 gears and 32's, and it was fine on the motor at around 10.7's and 6400 at the traps. Put 175hp through it at around 650hp and it well maxed out at 7000 with 6-pk rods, and would've needed a drop to 4.56 or 4.30 gears where it probably would've run quicker than 9.96.....Ideal scenario would've been 5.13 gears and Ally rods, lighter pistons and turn 7500rpm+.
my chall has a 29.5 tire 456 gear
according to the tacho its turning 7,300 rpms at 146 mph at the big end

Posted: Sun Jul 01, 12 12:59 pm
by Pete
7300 is a long way from what Ma Mopar envisaged when these engines were originally designed ;) I think the original red line was 5200 or there abouts. Thanks heavens for improved materials and lighter pistons....

Posted: Sun Jul 01, 12 1:04 pm
by Mick
my chall has a 29.5 tire 456 gear
according to the tacho its turning 7,300 rpms at 146 mph at the big end[/quote]

Yours must build revs very quickly, mine would be doing around 67-6800 with that size tyre, i have 4.56 gears.
Then again, i feel my motor is fairly mild anyway, car is relatively light though, 3100 or so with me in it, at a guess.
What are you bringing to the mopars Dunc ? and are any of the other crewe guys racing.
Mick

Posted: Sun Jul 01, 12 1:08 pm
by Pete
Due to a Big motor, Mick.

Time to build that stroker and get some BIG heads on it, it's only money (and your health!!!).

I think you have a nice balance of a quick and interesting car that you can enjoy without another mortgage....having fun is what counts!!!

Posted: Sun Jul 01, 12 2:24 pm
by Les Szabo
Cannonball wrote:
Les Szabo wrote:Going for lower tyres with less gearing with the same hp will result in a slower car unless your already overring at the traps.
You need to run your car as low as you can, with tubs and a tall tyre and low gear for best 60's, ET and stability. Its an increase in HP that will dictate a drop in gearing with a given tyre height.
The '69 ran 4.88 gears and 32's, and it was fine on the motor at around 10.7's and 6400 at the traps. Put 175hp through it at around 650hp and it well maxed out at 7000 with 6-pk rods, and would've needed a drop to 4.56 or 4.30 gears where it probably would've run quicker than 9.96.....Ideal scenario would've been 5.13 gears and Ally rods, lighter pistons and turn 7500rpm+.
my chall has a 29.5 tire 456 gear
according to the tacho its turning 7,300 rpms at 146 mph at the big end
Thats very good mph for a 9.4....your car must've been well light and pushing out close to 700hp.

Posted: Sun Jul 01, 12 2:44 pm
by pete walton
Mick i have read a million things on the internet about caltracs and launching straight....seems some people out there swear by rear sway bars...the bigger the better?????also found this ..might be of some use to someone out there :thumbright: :thumbright:

Posted: Sun Jul 01, 12 3:19 pm
by Les Szabo
thats good all round info not just for c/tracs Pete, hope you sort it, should knock an as eay 1 sec off your times I would've thought. :thumbright:

Posted: Sun Jul 01, 12 5:32 pm
by Mick
I'm fairly happy with what i've got, it's a 10 sec car, even on a bad day. Unless the motor blows up, i will keep it as is, just do small things to it.
Rear anti roll bars are for seriously fast cars, I took my anti roll bar off the front, to help it launch better.
Pete, no caltracs on my car.
Mick

Posted: Sun Jul 01, 12 5:39 pm
by Cannonball
Les Szabo wrote:
Cannonball wrote:
Les Szabo wrote:Going for lower tyres with less gearing with the same hp will result in a slower car unless your already overring at the traps.
You need to run your car as low as you can, with tubs and a tall tyre and low gear for best 60's, ET and stability. Its an increase in HP that will dictate a drop in gearing with a given tyre height.
The '69 ran 4.88 gears and 32's, and it was fine on the motor at around 10.7's and 6400 at the traps. Put 175hp through it at around 650hp and it well maxed out at 7000 with 6-pk rods, and would've needed a drop to 4.56 or 4.30 gears where it probably would've run quicker than 9.96.....Ideal scenario would've been 5.13 gears and Ally rods, lighter pistons and turn 7500rpm+.
my chall has a 29.5 tire 456 gear
according to the tacho its turning 7,300 rpms at 146 mph at the big end
Thats very good mph for a 9.4....your car must've been well light and pushing out close to 700hp.
3,800lbs 960 hp,

Posted: Sun Jul 01, 12 6:03 pm
by Blue
Pete, that baseline tuning is the way I would start. My initial set up was very similar, only I started with the rear shocks at fully loose. What you often get with caltracs is "Porposing", the car rocks back and forth after the launch. I just clicked the shocks up one step a run until it went away. I'd also be adding 100lb of ballast in the boot, I think your car will be very nose heavy which can make for some very "interesting" handling...

Posted: Sun Jul 01, 12 10:05 pm
by Pete
I jammed a heavy duty trolley jack into the very back of the Plodge when it was going a bit unstable and that was enough to sort it out at the speeds Roydon was going (128mph). There's a lot to be said for ballast at the back.......