At the request of a forum member, I did a test to see if my "Cheap Stock airbox mod" did anything for performance in a 40 to 80mph test. The test was done in the early evening at about 60 degrees on flat ground with no wind. Get the car in 3rd gear at 35mph. Floor it, and start the timer at 40mph. Stay in 3rd, and stop the timer at 80.

My average time with the stock box was 5.48 seconds. The average time with the modded box was 5.27.

I'm not looking for your fastest time. I would like to see your average time. This will remove some timing errors. I had a 5.12 which was probably a timing error.

Please list your mods.

If you are interested in the airbox mod, let me know.

https://www.rx7club.com/forum/showth...5&pagenumber=1

Thanks, Adam

 

I'd rather do a 75-140, its much more fun

haha

STEPHEN

 

I did a 5.67 when I was plain stock.
I will chek with my mods as soon a i get my boost gage installed

 

5.58 from a Datalog file

intake,dp,cb,hi flow cat,smic,twin power

 

wow, knocking almost 1/4 second off your time with the "cheap bastard" airbox mod is pretty good - I did the RB air inlet with K/N drop in and it worked the same as any other CAI - I now have the picnic basket sized RE Amenyia intake (hot) air intake - all works good. I'll have to try this 40-80 sometime. I know they did the 40-70 test for a while to see if your boost was working properly - most stock FDs would do it in about 5 seconds. My best time with non-seq turbos with all bolt-ons was 3.50 seconds.

 

Why not start in second?

 

If you start in second the how fast you shift will make more difference than the mod. Plus, then you gotta shift with a stop watch in your hand. Plus, the whole idea is to measure a broad power band not just top RPM's

 

That's a good point ...... I can shift with a video camera in my hand. Makes for some interesting footage.

 

It's been posted many times, but I still think you should start the timer RIGHT when you go to WOT. Giving your turbo(s) the time to spool up is almost like cheating.

It should depend on the instant acceleration from start speed to stop speed.

To me it's almost like starting a 1/4 mile race from 15 mph when you've already had a chance to start off.

But then again that's just me.

If you guys would actually go out and do that again with a stop watch, I'd LOVE to see what the difference in times are between the 35, start at 40 times are. Compared to the start timing @ 35.

I'd do it, but I don't have an engine in my engine bay

But do expect me to revive this post after mine gets broken in!

 

40 to 140 is much more fun.....I think I'll go start my own thread

 

That does sound like fun. I'm not sure that it's a good idea to encourage people to drive 140mph. Bad things can happen very quickly at that speed.

 

3rd gear pull 40-80 times
metric equivalent measured: 64-129 KPH

began acceleration at 35 mph/56 kph

Results:

5.4x repeatable at .85 boost
5.1x repeatable at 1.10 boost

Based on data collected from datalogit runs.

Top RPM hit: 8100
Highest AITs logged: 37 degrees C
Highest Coolant Ts logged: 86 degrees C
Range of AFRs logged at WOT:11.5-12.3

That's with a RX6 Single guys (spools nice and quick as compared to seq twins?..... I'd say!)

 

Just brake boost at 40.

 

But we DONT want to measure how fast turbos spool up. That the whole point !
We are trying to compare pure horsepower across a broad RPM range. Apples to apples.

 

Then brake boosting would be perfect.

 

Those who are unable to follow the rules will not be allowed to play, and will have a mark on their PERMANENT record!!

 

What's the difference of flooring it at 35mph and just brake boosting from 40????

 

No, it would be OK, but not better.
Everyone would have to agree on how long to brake boost and how close to hold the speed to 40. meanwhile your burning brake pad for NO reason.

Why does everyone want to argue with a simple consistent procedure. If you dont like it start another thread.

Like 0- 97.33 - 43 - 117 MPH test WHATVER

 

0-160. I like that test.

 

I'd love to try a 40-80 test, but the weather is saying otherwise right now.

 

Those are good times. .85 boost, is that around 12psi? Doesn't seem like there is much power available for anyone below 55mph in this test.

 

Nah, just accelerate up to 140 and then brake down--doesn't take very long. I've prolly done it over one thousand times in my R1 with no ill consequences .

 

Wow, your times are similar to the RX6.

 

Those speeds make the trip from SA to College Station go by quickly.

 

whoopsie.