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RWKW to run mid 11's

drag racing rwkw t5 9inch 235rwkw quarter mile

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#1 _383lhslr_

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Posted 08 October 2013 - 09:37 PM

Hey guys,

 

How many RWKW would it take too run a mid 11 over the quarter mile with this setup?

I have 235rwkw, 9inch diff and a t5 with a upgraded cable clutch,

What times would I be looking at with this as it is now with say 1.80 60 foot times?

 

Cheers



#2 Ice

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Posted 08 October 2013 - 09:48 PM

Would all depend on diff ratio one would think

Are you running slicks

#3 mitchg

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Posted 08 October 2013 - 09:48 PM

Just a guess but i reckon 280rwkw in a torana gets you a mid 11 consistently. With 235rwkw id say in the mid to low 12 region.

Only one way to find out though.

#4 _383lhslr_

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Posted 08 October 2013 - 10:23 PM

I'm not sure on the diff ratio, i would do a run with and without slicks most likely, and yeah only one way to find out I guess.

 

Cheers for the replies.



#5 _Bomber Watson_

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Posted 08 October 2013 - 11:06 PM

Unless its covered in lead then you should easily go high 11 with that kinda oomph at the treads, so long as the dyno wasnt half pissed and happy as a lark when the figure was taken.

 

Cheers.



#6 _LHSL308_

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Posted 09 October 2013 - 07:25 AM

I'm not sure on the diff ratio, i would do a run with and without slicks most likely, and yeah only one way to find out I guess.

 

Cheers for the replies.

Just jack the rear up and turn the rear wheel by hand 10 times all while counting how many times the tailshafts turns. Divide the tailshaft turns by the 10 revolutions you have turned your rear wheel and then you have your diff ratio. i.e- 35 divide by 10= 3.5 ratio.


Edited by Gonedeaf, 09 October 2013 - 07:27 AM.


#7 _383lhslr_

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Posted 09 October 2013 - 03:50 PM

Yeah i'm hoping to go in the 11's, and yeah I might just do that to find out the diff ratio.

 

Much appreciated 



#8 _Blackxu1_

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Posted 09 October 2013 - 08:22 PM

Google hp 1/4 mile calculators put in you weight and 1/4 time you want and it will tell you how much hp you need

Mine went 11.7 121mph I put the mph and weight into the cal and it told me I have 450hp at the engine

#9 _LHSL308_

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Posted 09 October 2013 - 08:41 PM

Google hp 1/4 mile calculators put in you weight and 1/4 time you want and it will tell you how much hp you need

Mine went 11.7 121mph I put the mph and weight into the cal and it told me I have 450hp at the engine

Interesting i'll be wrapped if I can go that quick.



#10 _383lhslr_

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Posted 09 October 2013 - 08:43 PM

I have 235kW at the treads, which is 315HP at the treads, Which I think roughly is 425HP at the fly?

 

Cheers



Interesting i'll be wrapped if I can go that quick.

What kind of HP you got at the fly?



#11 _383lhslr_

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Posted 09 October 2013 - 08:48 PM

Google hp 1/4 mile calculators put in you weight and 1/4 time you want and it will tell you how much hp you need

Mine went 11.7 121mph I put the mph and weight into the cal and it told me I have 450hp at the engine

Just wondering what weight you put in? don't mean to sound rood or ignorant but I done a few different calculations on a few different sites and I got all different answers, so i'm not to sure if they are accurate.

 

Cheers



#12 _Bomber Watson_

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Posted 09 October 2013 - 08:58 PM

Go to autobarn and spring $20 for the moroso slide rule.

 

Only accurate HP measurement.

 

Cheers.



#13 _383lhslr_

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Posted 09 October 2013 - 09:29 PM

I will

 

Cheers



#14 ls2lxhatch

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Posted 09 October 2013 - 10:05 PM

This is a typical formula used by a simple HP calculator.

 

HP = ( MPH / 233 ) ^ 3 * lbs

 

This is the formula used by a simple mph calculator.

 

MPH = ( (HP / lbs ) ^ .333333 ) * 233

 

This is a typical formula used by a simple ET calculator.

 

ET = ( ( lbs  / HP) ^ .333333)  * 5.825

 

 

They are handy calculations to be used as a rough guide but that's about all it is. Relying on a formula with two variables to accurately predict the performance of a car on a drag strip is rather optimistic.

 

At the end of the day such a simple formula will only be able to produce a rough guess that is not bad for a NA engine. If you have a forced induction engine then it is going to be even more inaccurate. According to the simple formulas a 600 hp 3.0L turbo engine will perform exactly the same as a 600 hp 8.0L naturally aspirated engine over the 1/4 mile.

 

 

 

This is what the parameters for a more comprehensive computer model looks like. If you were to input the figures from a dyno run into this sort of computer model then you would expect it to be reasonably accurate.

 

You can download a free trial from here.

http://performancetr...ag_race_pro.htm

 

cm01.jpg

 

cm02.jpg

 

cm03.jpg

 

cm04.jpg

 

cm05.jpg

 

cm06.jpg

 

cm07.jpg

 

 



#15 _Bomber Watson_

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Posted 09 October 2013 - 10:25 PM

But the slide rule is much easyer to use drunk Andy.



#16 Lima31

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Posted 09 October 2013 - 11:44 PM


I have a Moroso slide rule, 425bhp and 3,130lbs indicates 10.9s ET @ 122mph.

 

Same power and weight with the above equations from lslxhatch is 11.3s @ 120mph.


Edited by Lima31, 09 October 2013 - 11:47 PM.


#17 gtrboyy

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Posted 10 October 2013 - 12:44 AM

Auto,big stallie,minimum 26" slicks & 3.9-4.11 gears yes probably can.

 

With t5 if it doesn't explode on you for driving car like you stole it most likely low 12 although with right setup & you can really drive stickshift with perfect set up 'maybe' if all comes together.T5 won't like big launches on slicks or hard/fast changes with 400hp engine for long imho.

 

Slicks? Diff gears? clutch?



#18 _Quagmire_

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Posted 10 October 2013 - 01:57 AM

Auto,big stallie,minimum 26" slicks & 3.9-4.11 gears yes probably can.
 
With t5 if it doesn't explode on you for driving car like you stole it most likely low 12 although with right setup & you can really drive stickshift with perfect set up 'maybe' if all comes together.T5 won't like big launches on slicks or hard/fast changes with 400hp engine for long imho.
 
Slicks? Diff gears? clutch?

you can upgrade em
but for the price of the "kits" you move into the region of why bother i'll just buy a decent tremec 5 spd
territory

#19 ls2lxhatch

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Posted 10 October 2013 - 02:14 AM

I have a Moroso slide rule, 425bhp and 3,130lbs indicates 10.9s ET @ 122mph.

 

Same power and weight with the above equations from lslxhatch is 11.3s @ 120mph.

 

 

I have seen the constant 233 in the formula above vary between 230 and 234. You will probably find a number in that range that lines up the Moroso slide rule. Any answer that is generated by a slide rule or two variable formula should only be considered as a wild guess at best. The peak HP of an engine tells you nothing about the power curve of the engine.

 

A far more complicated computer model with 100 plus variables like the Drag Race Pro software plus accurate dyno results throughout the rpm range and vehicle weights with driver and fuel is required if you want to get a more accurate idea of a vehicles 1/4 mile potential.


Edited by ls2lxhatch, 10 October 2013 - 02:16 AM.


#20 _383lhslr_

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Posted 10 October 2013 - 06:42 AM

I didn't put the T5 in I brought like that, it seems reasonably strong, I think I will have to take it to the drag strip to see what I can run!

 

Cheers guys



#21 _rb3torana_

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Posted 10 October 2013 - 10:28 AM

I use this formular

0.00426 x MPH = value x same value x same value x race weight in pounds = HP or on a cheap calculator lol.
0.00426 x MPH x = = x weight = HP 
eg. 0.00426 x 125 = 0.5325 x 0.5325 = 0.28355625 x 0.5325 = 0.150993703125 x 3000 = 452hp

Converting rwhp to flywheel. rwhp / 0.88 = flywheel hp
eg.320 / 0.88 = 363hp.

 

Cheers



#22 LXCHEV

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Posted 10 October 2013 - 01:42 PM

Auto,big stallie,minimum 26" slicks & 3.9-4.11 gears yes probably can.

 

With t5 if it doesn't explode on you for driving car like you stole it most likely low 12 although with right setup & you can really drive stickshift with perfect set up 'maybe' if all comes together.T5 won't like big launches on slicks or hard/fast changes with 400hp engine for long imho.

 

Slicks? Diff gears? clutch?

 

I completely agree with what gtrboyy said above regarding E.T.

 

I'm probably a good person to make comment here, as our cars are near-identical in power levels.

 

At it's peak, my old 383 SBC produced 245 rwkw. Car weighed around 1480kg with driver. With loads of torque, a 3200 hi-stall (TH350), and 3.7's, with M/T ET Street Radials, it ran a best of 11.77 @ 115MPH. There was nothing left in it. Perfect traction, 60 foot times of 1.69 from memory.

 

In other configurations (smaller exhaust), my car made 235rwkw and ran 11.9's and 12.0's.

 

Hope this helps.



#23 _Blackxu1_

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Posted 10 October 2013 - 05:36 PM

If you can turn the tyres into top on the street you can run 11s lol

#24 _383lhslr_

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Posted 10 October 2013 - 06:58 PM

If you can turn the tyres into top on the street you can run 11s lol

Hahaha it spins in 3rd so easily not sure about 4th and 5th though



#25 _383lhslr_

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Posted 10 October 2013 - 07:05 PM

I completely agree with what gtrboyy said above regarding E.T.

 

I'm probably a good person to make comment here, as our cars are near-identical in power levels.

 

At it's peak, my old 383 SBC produced 245 rwkw. Car weighed around 1480kg with driver. With loads of torque, a 3200 hi-stall (TH350), and 3.7's, with M/T ET Street Radials, it ran a best of 11.77 @ 115MPH. There was nothing left in it. Perfect traction, 60 foot times of 1.69 from memory.

 

In other configurations (smaller exhaust), my car made 235rwkw and ran 11.9's and 12.0's.

 

Hope this helps.

I would be happy with that any day, it sucks to think that a lot of the newer holden and fords with not that much work done are just as quick, but then a whole different experience driving a commodore with a fair bit of power and a torana with a fair bit of power. Ah well maybe one day i'll have to put a 350 in it and try make relatively big horsepower, after all it only a 308

 

Cheers 







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