Dyno peeps...

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xj0hnx

I wanna be sedated
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Ok, so I went ot the dyno today, not the best, but it's the only one in town. New addition is CTR cams. Anyway here's the last one 155whp...

s405f5a9e641a9.jpg


As you can see the first run was 112Kw which is 150whp, then I added +3 fuel all the way across both narrow and wide throttle and got the secong 116Kw which was the peak of 155.56whp at 8000rpms. Ok, decent...

Now I put in the CTR cams and could feel a nice difference, so I was excited about going today, well here's the results...

s405f5bef7a139.jpg


So as you can see, I was back to the original 150, with the VAFC "tuned" to the same +3

That run was done in fifth gear @8000rpms and 225Km/h 139.81mph :)

Now this one, was done in fourth, thinking well maybe fifth was just weak, but as you can see, no it is the same...

s405f5b9335b81.jpg


There was one inbetween the last two, where I flattened the VAFC and ran in fourth, but since it was the same, there was no need to waste space.

So ok, I asked the guy what he thought was wrong, and he said nothing, one thing was hte atmosphere he said maybe different today, so that would affect it too. Also he noticed that the climb was a LOT smoother, and I gained about 6lbs-ft of torque (8ish Nm) that would explain the better feeling when driving.


Cliffnotes, lost 5whp and gain 5 lbs-ft of torque with CTR cams.

Anyway, thoughts speculations, better interpetations of the dynos, let's hear it.
 
From what I have always understood, you should run the car in forth for the most acurate numbers due to diffrent gearing results in trq mulitpication. You aim for a 1:1 gear ratio and for does the best at it.


Do you have cam gears? I would assume that the b16a2 gears are slightly timed diffrent then the b16b gears. I would think your next logical mod would be some adjustable cam gears. You might want to play with that.


Do they have a wideband 02 sensor? That would be the best way to determind what you need to set your VAFC fuel maps at.
 
Cam gears are definitely on my list, but right now I have a suspension issue in the works. No, unfortunely the shop isn't tuner shop, just an Autoshop that does certifications for TUV (German DOT) so they have a dyno, but no tuning equipment.
 
yea, what I am guessing is your a/f Ratio is all screwed up.
 
I tried playing with it, but we ran out of time, and the adjustments I was making weren't doing shit :(

Anyway, I realize they need to be tuned, but the gain in torque is what got me, coupled with the loss in Hp.
 
Originally posted by asmallsol@Mar 22 2004, 02:16 PM
yea, what I am guessing is your a/f Ratio is all screwed up.

exactly what i was thinking... honda's usually run too rich in the higher rpms, you should be removing fuel not adding... infact get that bitch on a wideband, this is a must if you want to make any use out of your VAFC.

EDIT: and cam gears don't do much with CTR cams, after tuning on mine Ex was left at 0 and In was at +3.
also, what ignition timing are you running?
 
make that your next mod. There are wideband kits out there for 200 or so. On honda-tech, they have a DIY thing for some of the items. Then just try and get it stuckiometric (something like that)
 
yea, hondas do run rich in higher rpms, its mostly vtec, but with the vafc you should lean it out very little right before vtec, then lean out vtec a little more, i've heard this tends to work the best, its how i had my hack setup before i got hondata and it ran good. You only lean it out by like 3 points at the most. i think you've got an airflo issue (backpressure) which is odd because of the i/h/e, i'd try to get a hi-flow cat or punch the stock one out, because the ctr cams shouldn't have lost any hp, if anything i think they'd lose a little tq, i agree with the cam gears to
 
Originally posted by B16+Mar 23 2004, 01:28 AM-->
asmallsol
@Mar 22 2004, 02:16 PM
yea, what I am guessing is your a/f Ratio is all screwed up.

exactly what i was thinking... honda's usually run too rich in the higher rpms, you should be removing fuel not adding... infact get that bitch on a wideband, this is a must if you want to make any use out of your VAFC.

EDIT: and cam gears don't do much with CTR cams, after tuning on mine Ex was left at 0 and In was at +3.
also, what ignition timing are you running?

Timing is set for stock B16A, he didn't want to advance it because I use the gas on post, which 90 is the best there is.

i'd try to get a hi-flow cat or punch the stock one out

I'm using a Car Sound.


Haha, it took me months to move one wire at my ECU, I can only imagine how long it would take me to get the nerve to build that.
 
yes 3rd gear. I can't believe they had you dynoed in 5th before.
 
Uh all the cars I have worked with both N/A and blown have always made 4th gear pulls. Including my Civic DX, my old Jetta, my roommates old spec miata, and his new blown miata. And most of my buddies honda's they all have made 4th gear pulls as you are trying to get as close to a 1:1 ratio as possible, maybe if you had an ITR or CTR tranny then another gear might be more realistic for you.
 
see thats the thing, being both FI and NA I was always told that the two made differnt pulls on dynos....

BUT - I have no hard facts to prove it - just hear say,


well considering how well you "b16vx" made out on those seats, from the savings/procedes, I would go make a pull in 3rd, 4th, and 5th for shit sake?? :)
 
Originally posted by JDMilan@Mar 24 2004, 05:16 AM
see thats the thing, being both FI and NA I was always told that the two made differnt pulls on dynos....

BUT - I have no hard facts to prove it - just hear say,


well considering how well you "b16vx" made out on those seats, from the savings/procedes, I would go make a pull in 3rd, 4th, and 5th for shit sake?? :)

Haha, that extra savings went to coilovers and now shocks to go with them :)



And most of my buddies honda's they all have made 4th gear pulls as you are trying to get as close to a 1:1 ratio as possible, maybe if you had an ITR or CTR tranny then another gear might be more realistic for you.


Y21 has the same gear ratio as the CTR and USDM ITR :) just no LSD :(
 
Originally posted by 92b16vx@Mar 24 2004, 01:56 AM
Haha, that extra savings went to coilovers and now shocks to go with them :)

w00t

Yet another one of Mike's suspension components ends up on John's car.

:lmao: :thumbsup: :thumbsup:
 
Like collin said, 1:1 is the gear you want to dyno in. 5th is defintely not the answer.

with less or more than 1:1, you are fighting the engines' VE (1st, 2nd, 5th)

Most honda's fall in 4th gear for the closest to 1:1, but tighter trannys and tire size can effect this one way or the other.

people move to 3rd gear pulls for two reasons-
1, its easier on the motor. it taes much less time to hit redline in 3rd than it does in 4th, thus, saving time and dyno cost money and makes for back to back runs easier on the motor.
2, 90% of the time you are racing, 3rd gear is your longest/most used gear- ie, 60-100 is your average speed, most likely- be it drag or track, and thus, thats the gear you want to be tuned the best for.

4th gear is not only closer to 1:1, but it puts more load on the motor. On a turbo car, or high-power all motor set up- load is good. the ELD will detect such a thing, and thus, the motor will run a little stronger. also, roots (JRSC) blower cars will also make 20+ more hp on a 4th gear pull because of the speed of the crank pulley in 4th will actually create slightly more boost as a result of the higher speed.

In general,
4th gear dynos on lower power cars will be lower than 3rd gear pulls
4th gear dynos on higher power cars will be higher than 3rd gear pulls

In addition to getting your car at 1:1, the dyno itself needs to be set. The dyno operator needs to set the dyno into reading a specific ratio... some range from 1.5 to 5.0 rpms, with most dyno jet setups being in the low 3.0x's due to the size of the roller brake itself.

a HUGE part of dyno tuning is setting up the car wieght for the dyno. That's how they work. they add resistance based on the weight of the car to simulate acceleration. if you're pulling based on a 3000 Kilo :lol: truck, your dyno will be significantly lower than it would be if it were at the 2500 lbs your car probably weighs with you/dyno driver in it.

it gets even MORE complicated...

on new dynojets (248's) it doesn't really matter that much because the dyno taps off the spark reading (for rpms, etc...) and also reads the wheels rotational mass of the wheels and calculates for it. The difference is very, very slight on most cars however thats only if the gear ratio is close between the two gears your compairing. With jdm type R's for example 3 and 4th gear runs are practically identical.

Considering that you are not on a tuning dyno, i would say that you are really making much more power than what you are getting for results.

Now, for the tuning aspect.
:)

Without a wideband, you're in the dark. but off the bat, i'll tell you that you're going to want to go like this:
<disclaimer>if you blow up, its not my fault </disclaimer>

at low rpms the cams are pretty similar to b16a's and thus i wouldn't do anything to the low band.
I would change the vtec x-over to about 5500.
from 5500-redline, I would take off -1% for every 500

5500 -1
6000 -2
6500 -3
7000 -4
7500 -5
8000 -6
8500 -7

The higher you go, the more vacuum is created in the system. vacuum pulls the FPR hard. more vacuum from larger cams = the need for more cut of fuel via the vafc.

look at bills dyno in the all motor Ls thread. using the stock LS comptuer with the larger cams and much higher compression, he was STILL running rich from 5500 up. forced induction rich. and rich robs power. you're in the same situation. i wouldn't be suprised if you were hitting 12:1 a/f from 6000 on up.
 
Holy shit B, I haven't seen you post that much info in one shot in a while :) haha

So, I am thinking I am running rich too, because when I start it up, there is the aroma of fuel a lot more than before, but during warm up you run rich anyway, so that may just be retarded, but I haven't noticed the smell before a couple days ago.

I'll try to settings you suggested, not run it hard and see what gives. I have never messed with those settings before, only the linear graph type fuel setting menu (forgot which one of the top of my head).

Oh my vtec right now is set at 5400 lo->hi and 4800 hi->lo. actually test it on this crappy dyno to make more power, but I can play with them a bit on the next trip. Also some of the local (around Germany) guys, are looking into a dyno day, at a real shop, so if that comes through maybe I can get a real number.
 
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