So...

The setup is pretty basic:

B16A
84.7mm stroker kit
12:1 compression
Stock intake
Stock TB
Blox B cams
Blox springs
KMS retainers


The car was fully tuned by me on both headers...




The improvement was very significative, but there is this big dip after VTEC, even with it set at 5900rpm... And then there is this second dip...

Can this be related to the small tb/intake? I have one performerX laying around, I may try it next week, to see if I can get some better powerband..

oh, and this is the graph without VTEC, on the bisi header...



For some reason the power still climbing better than Vtec'ed until 6500rpm, but I don't believe it's very safe to set VTEC that high...

 

Oh, I forgot to mention, 2.5" exhaust with crush bends

 

Which is which?

Off topic, but I'll be in Sao Paulo later this year. Been there before and I love Brazil...looking forward to a good steak Are there any shops down there I should visit?

 

The Bisi one is the highest...

Well, you could visit our shop haha, it's not really a shop, more like a bunch of friends messing up with old Hondas.. But it's cool .

Let me know when you come to Brazil, I can help you with whatever you need.

 

I will look you up when I head down. I don't know the exact dates, but should be late summer. I will be working most of the time, but should have some spare time to come say hello.

 

Are you gonna be working on cars or other business?

 

Fully tuned but horrible vtec cross over point. Lol. 'tuner'

 

Wow jackass, I guess you were born tuning. Lol, at the stupid **** you post 99% of the time.
Better yet, lets not forget these gems of knowledge:

(1) dynojet is a industry standard
(2) you can change the calibration on a dynapack.

Lol, indeed


OP,

Give the PerfX a shot. This may help with the vtec cross-over.

 

Dude... I know I should set VTEC to 6400 for an optimal powerband, but I dont like the fact that VTEC will be engaging and disengaging on every gear change... It's basically a trackday car, that is 90% of the time reving between 6000 and 8400rpm.

Anyway, the dip should't be there, as you can see, the curve is perfect with the crappy header, and VTEC was set arround 5400


Now, seriously, stop being an ***, I'm not a tuner, I'm not a mechanic, I'm just a enthusiast, and I built the whole thing myself, show some respect, or gtfo.


Thanks for the input, I'll try that on monday, also, I borrowed a 68mm TB, which I believe will help a lot too.

 

surprised that the haters didn't come out yet

 

a b16 can take way higher rev (at least 10k if it makes power)
and stg2 cams will carry the powerband atleast til 8400rpm

set vtec to whatever your motor likes vtec at 7100 is normal for alot of stg 3

 

" I guess you were born tuning. " Lmfao

 

I had the same problem with a dip like that on a 85mm b20v with sk2 s3 cams. no matter what we did we couldn't get rid of it... so I just dealt with it lol. car was still fast and fun.

 

at first I was like why the hell is your tq so high, then I saw it is rated in nm

 

so thats 16 hp and 13.6 tq. not bad. at least i know it wasn't a complete waste of money. and it'll be about the same setup minus the 84.7mm.

thanks for the post/ 3rd party dyno.

 

yup lol.......
we ve test enuff to know.......
we r testing a stock b16 rite now and its at 518whp
and it s reving to 10k

 

OP, We have seen this on small engines as well. The header made top end because it is a little to big which isn't good for the low Vtec crossover. We built a B16 12.5-13:1 compression with Pro 2's and the crossover was about 7100. Stock Skunk2 Pro-series intake manifold and a small tube rage header.

 

Setting vtec high isn't bad.. infact, its a big mis conception..

You dont want to fall out of vtec everytime you shift, thats bad, this is what creates the stress everyone refers too. I had vtec set on pro2's @ 6400rpms but i had a short tranny and everytime i shifted i would fall back into 7k

What was the overall timing / AFR and cam gear settings?


Marc is right.. i'm a dick to someone who wants to sac ride a part because his buddy's ethug friend uses it.. you never see me be a dick to someone who actually contributes or tries to better himself, his shop and his customers because he wants to become better @ tuning.. you gotta start somewhere turbociv910.

68TB would be ideal i believe, with the performerX.. you wont need to rev as high as well..

 

Some people say the the problem with the high Vtec point is the LMA's float with more aggressive low cams like the Pro series so that would cause abnormal wear on the rocker. IF you don't want this to happen don't build a combo that requires a high Vtec point which tells you the engine would probably make a better graph with smaller cams... I.E everybody that wants to run Pro 3'a on a 10:1 B16...

 

That.. and the fact that, you make sure your motor is able to handle bigger cams...rocker arms included.

 

I'm super exhausted after 3 hours of dyno with no good results..

Yes It made more power... 6whp up top to be more precise, but the dip is EVEN BIGGER... But now it's different, Vtec kicks in @ 5900 RPM, it still climbs a little, but then just fall on it's face until 6400rpm...


well, let the graph do the talking






By the way, I played intake tube lenght, and it made A GINORMOUS DIFFERENCE...

With about 20 inches, the curva was very stupid, with nothing but the stack I got this 196whp but the dip was pretty nasty..

BUT, with about 8" plus the stack, I got a curve very similar to the one from the stock mani.

THis is what I'm running now and it's probably what I'll run in the track, but I was so exhausted at the dyno, that I forgot to print many things...


What could possibly cause such a big differece between intake lenghts? Also, I noticed that the MAP sensor was reading 750mbar on WOT close to revcut, could that be indicating that tha TB is too small?




settings are 0 for exhaust and 1adv for the intake.. As I have only one adj cam gear.
Lambda is set arround .85


here is a screenshot of the maps:

 

I'll try VTEC at 6800 tomorrow.. I now this is crapily tuned, fuel is everywhere between .80 and .88 but sometimes your head is so ****ed up after days and hours of no sleep, that **** gets crazy.

But I'm sure this can't get MUCH better, maybe 3 or 4whp here or there, but it's not gonna be perfect with this physical setup.



Just a pic of the car.. And yes, the intake tube is PVC, so I could cut it on the dyno, and check results

 

i think a 68mm tb is needed....if ur not seeing about 900+mbar...ur getting disturbence somewhere in the air flow...something in the manifold is not right..

 

resonance does that to you, and i think it's extrapolated because of the 750mbar issue.

stock tb is defenatly choking it somehow, the crush bent exhaust is'nt helping either, run it open header and see if that's causing the dip.
not being able to tune the cam gears limits your options also.

intake/exhaust is now like this:
pipe/tb/mani/engine/header/exhaust
-----__----------/ \--------------_________
___----______\ /_________-----------

not really ideal i'd say, 68mm TB and true 2.5" freeflow exhaust will smooth it out IMO

 

I saw like a 2whp gain by running open header, and the curve was pretty much the same.. I think that the TB is choking the engine pretty badly, that could be why I was seing 750mbar, while ATM pressure was like 920


I'll race it like that on sunday, hoping it stays in one piece, and then next year I'll try a 68mm TB, and add another cam gear...




I don't know if you guys remember, but I posted a thread about this engine, and it's so full of FAIL, that I'm impressed that it handled 150 passes on the dyno.

Crank is grounded .50mm, pistons are shaved to fit the block, and P2H is so close, that I just can't understand how the piston is not touching the head or valves, even with 5 deg advance on the intake gear..


Anyway, even though it's epic crappyness, it's the country's strongest B-series, and I may say, one of the fastest all motor Hondas arround.



BTW, I almost ran the car with NO TB at the dyno... but I didn't have a vacuum line to hook the MAP up in another place