technonovice

We should'nt use 1/4 mi times as a gauge when talking about mods. The 40-70 mph in 3rd gear test is awesome for gathering test numbers.

It is easy to do and gets rid of launching and shifting vaiables. You can time your car, then do a mod or tune, and retest.

Here is how for those wqho have not seen it.

You need a flat straight away preferably one that would allow you to run it both directions so you can average the times to account for wind.

Start by maintaining a steady 35mph in 3rd gear.
Floor it!
At 40 mph hit the timer...a stopwatch is fine.
Keep it floored and in 3rd gear.
Stop the timer at 70 mph.
Repeat as neccasary...careful it gets addictivley fun.

I've seen times range from 4.5 secs to 5.5 secs depending on mods and state of tune.

I'd be curious to see what mods do compared to stock times.

Happy testing. The last time I tested my Touring it was 5.15 secs...stock no mods with about 1/2 full tank and 65 degrees F.

SleepR1

NO TEXT

dannyB

At what RPMs should this test be done at? Won't that affect the results?

I agree w/ SleepR1 - the dyno doesn't lie...that much.

JoeD

i agree...there are too many variables with a 1/4 mile time.

however, the 40-70 test is great! also, im assuming the times would be much more consistant than the 1/4 mile test.

more people should be posting 40-70 acceleration numbers.

technonovice

What is wrong with a dyno?
1. I don't have one.
2. This test is free and can be done nearly any time.
3. A dyno can't tell you what weight reduction has done. I get signifigant variance from a full tank and a 1/4 tank.

Nothing wrong with a dyno... but why limit yourself to it?

Why are you asking about rpms? You do it in 3rd gear which uses most of the rpm band. Read back over it.

Oh obviously an avergae of several runs is the most accurate way to calculate it.

Greys 10th

"I get signifigant variance from a full tank and a 1/4 tank."

For those of you that dont know gas weighs appoximately 7lbs. per gallon...so you should see differences depending on how full you are.
later

pp13bnos

iTrader: (1)

What about wheel spin? CJ

mb7

Maybe good for the stock twins, but some of the big single turbo guys make more power higher up in the rpm range. They could have a 40-70 time in third gear identical to yours and then pull several carlengths 70-110 in third. In a 1/4 mile it would be no comparison. A dyno would probally be the best, but then using different types of dynos can yield different results, and also the fans they use to cool your intercooler can't really compare to the wind while you are driving on the road. Also a lot of people just look at peak horsepower, when actually its average horsepower in the rpm range that you use. The list could go on. But bottom line is that its hard to compare 2 cars with just some numbers on paper. Just my little rant...

technonovice

Exactly. Regarding the 1/4 mile, I love the numbers, but it is as much about skill as it is power. Thats great when you are talking about racing and does have value when comparing performance.

It is good measure of torque which is what is responsible for acceleration and what most of us are really after.

I think the 40-70 in 3rd gear gives us a cheap ...make that free, simple, and pretty reliable way to compare.

I'm disappointed that no one has posted any runs yet...other than me. I'd really like to compile a list that compares a stock, and various mods in several configurations:

stock
downpipe
intake
downpipe + catback
downpipe + catback + intake + ecu
whatever...

...you get the idea. When I told the 944 Turbo guys and the VW guys about this test they went ape. They love it now and the VW numbers would suprise you.

mb7

the VW numbers would suprise you

Yeah, and so would my numbers in second gear.

technonovice

So are you going to do the 3rd gear test or not?

If you have a 1/4 mi, I'd be curious on that too.

kwikrx7

I'll do the 40-70 test but I can't do a high end boost run until after Feb 5th because my timing maps are too high on my PFC and am getting dynotuned. I probably won't fare great in the 40-70 range because I'm running non-sequential and don't have full boost until 4K rpms which would be simililar to a small single FD. Maybe have sections like 50-80 and 60-90 fro some of us slower spoolers - I better get under 5 seconds in the 40-70! I'm sure I'd have a better 60-90 time than a 40-70 though. 40-70 is for sequentials :p

RotaryKnight

I think the new performance rating should be stop light to stop light!

"So hey man what you run a block in?" HAHAHA

QuIcKSiLvEr

Hey, i did this test quite awhile ago.. it was a somewhat misty night, not totally wet though.. and i did about 3-4 runs.. my average time was about 5.7s.. i have a stock 94 touring.. i had about full tank of gas and a 170lb passenger.. not sure if 5.7s is a good time.. what do u think technonovice?

mb7

Maybe we should start a new thread called "Post your 40-70 times"

technonovice

A new post has been started for the times to be listed.
https://www.rx7club.com/forum/showth...789#post346789