1968 605ci HEMI CUDA

Les Szabo · Post by **Les Szabo** » Thu Nov 21, 13 6:48 pm

Well these figures are not an absolute Paul as you have converter slip etc, but they are pretty damn close and worked almost spot on for my cars back in my day.

I think they are useful to use to make sure you got the right gears/tyres for your desired ET goals and engine rpm capabilities with a given combo, and you can factor in any given changes like adding N20.

There just simple figures anyone can use mate, as long as you got the weight of your car and preferably the hp, you can play around with gear/tyre/hp combo's, they will also give you a very good idea of what you should be running given a good front/rear end set up that hooks.

Les

Pete · Post by **Pete** » Thu Nov 21, 13 6:56 pm

It depends SO much on the car in question, it is not just Power and Weight.....

You look at the AWB, Altereds and track oilers - how many ever make a pass under full power for the lenght of the run.......

That car has plenty of potentail (it should have at that price) but I would never buzz a motor like that over 7K.....

Les Szabo · Post by **Les Szabo** » Thu Nov 21, 13 7:45 pm

ET/MPH comes from p/w, Gears/Tyre size = rpm through the traps. The latter will not have much affect on the first, unless of course you completely balls up your ratio/tyre size and put your motor out of or not in its power band at around half track.

This is based on the assumption that the car can hook and on a full power run using all its gearshifts. As I said its not an absolute, as there are variables, but a very good indicator to which you can work to if you understand the variables. And you have to assume that every run you make will be full power all the way, as thats how you race.

Using Tigs car as an example, he consistently runs 9.60's with 4.10's, and the odd 9.5 at 139>142mph, 29" slicks I think and weighs 3850+/- a few lbs?...with these figures applied it =

60 Foot E.T. : 1.32
1/8 Mile E.T. : 6.01
1/8 Mile Trap Speed : 113.08
1/4 Mile E.T. : 9.53
1/4 Mile Trap Speed : 141
1/4 Mile Trap RPM : 6,687

And thats with 880hp at the fly.

Les

Mossy68 · Post by **Mossy68** » Thu Nov 21, 13 8:10 pm

Interesting stuff this Les.
What's the maths behind it ?
Or is there a site where you can play about with gearing , tyre size etc and see how E.T's , etc alter ?

Cheers

db · Post by db » Thu Nov 21, 13 8:23 pm

Great stuff

Mossy68 · Post by **Mossy68** » Thu Nov 21, 13 8:42 pm

This looks interesting !

http://www.wallaceracing.com/Calculators.htm

Les Szabo · Post by **Les Szabo** » Thu Nov 21, 13 9:08 pm

thats it m8, I think this is one of my old posts, and Pete put this up as well.

Les

Pete · Post by **Pete** » Thu Nov 21, 13 9:11 pm

Aye!

According to this, the AWB will run a 7.2.

I think that's bollaxxx...so use with caution, but it is a good indicative tool on what a setup will potentially deliver - good for tyre height and Gear selection as Les says...

Mossy68 · Post by **Mossy68** » Thu Nov 21, 13 9:16 pm

Cheers chaps.
Well according to site the more door should run a 14.24 @ 94mph !!!

I think that's a bit optimistic don't you !

Pete · Post by **Pete** » Thu Nov 21, 13 9:18 pm

That depends on which car is towing it

Mossy68 · Post by **Mossy68** » Thu Nov 21, 13 9:20 pm

Pete wrote:That depends on which car is towing it

I was waiting for that !!

Les Szabo · Post by **Les Szabo** » Thu Nov 21, 13 9:25 pm

Hey Pete whats the AWB?..altered?....whats the figures?.....

Pete · Post by **Pete** » Thu Nov 21, 13 9:36 pm

125" Wheel base.
No suspension.
3.91:1 Gears.
33 x 14.5 x 15 Slicks.
1600lbs with driver. Maybe a bit lighter....had it weighed with an Iron BBC...
850 - 900bhp.
Turbo 400.
3 speed with Air Shift.
Transbrake.

Will probably run 8.50.....if I can....

Les Szabo · Post by **Les Szabo** » Thu Nov 21, 13 9:46 pm

ok, here's one last example.......Micks Dart....

590Hp, 3150lbs, 31" tyre, 4.56 gear, 2 shifts =

60 Foot E.T. : 1.42
1/8 Mile E.T. : 6.42
1/8 Mile Trap Speed : 105.82
1/4 Mile E.T. : 10.18
1/4 Mile Trap Speed : 132
1/4 Mile Trap RPM : 6,510

If you change that to 600hp =

60 Foot E.T. : 1.41
1/8 Mile E.T. : 6.39
1/8 Mile Trap Speed : 106.41
1/4 Mile E.T. : 10.12
1/4 Mile Trap Speed : 132
1/4 Mile Trap RPM : 6,547

The variables are launch, the air in the air for hp, converter slippage for trap rpm, but I think thats pretty close.

You gotta be realistic with your hp estimates and your weight if you don't know them exactly and adjust accordingly if you know what you've run before.

Les

Mossy68 · Post by **Mossy68** » Thu Nov 21, 13 9:49 pm

Well Pete.
If it all gets too much grab yourself a nice warm Lancaster and let a young rookie have a crack