I posted this in the FI forum, but i know some of the more knowledagble people are in this forum over the FI... But Im having an issue with my current setup and i have tried just about everything. Im in need of some help! If you can solve this issue you are trully a Honda Tech, and my hats off to you. Breakdown of the setup.

B18B1 Block:
GE sleeved block 82mm
9:1 CP pistons iirc
Manley rods
ACL barrings
ARP mains
ARP headstuds
balanced and blueprinted

B18C1 cyl head:
Supertech valve springs/retainers
Skunk2 Pro1 cams
Skunk2 IM
Edelbrock TB
1000cc inj
255lph walbro

Turbo setup:
FullRace T3 ramhorn
44mm Tial 1bar spring
GT3582R turbo
Spearco intercooler
2.5" custom charge piping
3" downpipe no cat
3" thermal exhaust
turbonetics bov

Hondata s300

Rundown of the chain of events. (footnotes)

On dyno tuning low cam first. Dial in low cam and continue to high cam. Engine performed flawless. Made consistent power of 380whp with ~17* ign timing at peak tq. afr @ 11.3 wot(1bar).

Next pull wastegate line blows off and engine makes strange noise. (similar to valve float.) Stop all tuning and compression check engine. 210psi on all 4 cyls. Reclamp wastegate line and attempt to continue tuning. However! We are nolonger able to rev pass approx ~6500. One pull will rev out fine to almost 7k, the next will breakup at 4200or between that rpm range... Car is pulling 15"-18" of vac and will rev out with no problem with NO LOAD.

The massive list of things i have jotted down to remeber everything i have tried...

checked tps voltage during dyno run at tps and ecu.. confirmed good
checked map voltage during dyno run at map and ecu.. confirmed good
map sensor wiring good to ecu. no shorts to ground
tried different 3bar map sensors all same results
visibly confirmed all wiring to distributor is good
checked distributor continuity to ecu all is good
checked for shorts to ground on distributor none found
checked volatage to coil/icm during dyno run confirmed 13.5 volts
new plugs, changed gap multiple times tighter and tighter each time. started at .022 currently at .010
tried 2 different known working HONDA distributors.. one off 406whp GSR other off 320whp B16.
ohm tested current spark plug wires (ngk 3k-8k) (magnacore 400ohms-600ohms)
tried new ngk spark plug wires same results
tried known used good Honda wires same results
confirmed afr is good and consistent. flat 11.3-11.5afr... same results
confirmed fuel pressure is holding and rising with boost ref. same results
removed cams and inspected/confirmed no broken valve springs
checked cam timing
checked ignition timing
tried different Hondata S300
no cels
car will rev pass 8k without boost no problem... log shows -4" to atmospheric pressure... def a boost (load) related issue.
confirmed no boost cut
confirmed no launch control
changed grounds
added grounds
compression tested engine 210 per cyl
made pull all motor and engine revd to 8k no problem
checked oil pressure at head port and confirmed consistent 80psi during vtec engaugement
checked vtec wiring and confirmed good
one pull will be fine the next will breakup between 4k-6k.
Car uses nowater
No overheating
No mixing of fluids
No pressurizing of coolant system
removed exhaust system and ran open downpipe and still problem persist

During that high boost pass something was disrupted. What that was is the question at hand !!!! any suggestions I have over looked ?

 

What brand wideband O2 and what's its condition? What type of fuel are you tuning with?

It's entirely possible that you are running richer than the wideband is indicating. possible rich misfire.

Do you run a reinforced flex pipe on your 3" DP? if it's a cheapo one they tend to collapse overtime.

also, how is the shaftplay on that turbo?

hope that helps.

 

Turbo ok?

 

Thanks for your response...Didnt inspect in the downpipe flexpipe. Will do in the morning! It is a Fullrace Dp didnt even think about the flex joint.. Good suggestion! 3week new Denso Dynojet Wideband. 93oct pump. ! bar spring in gate.

 

Climbing into boost and making consistent boost levels at breakup. will make a min of 10psi prior breakup and will not climb pass 1bar with boost reference on gate. No shaft play. Spins freely. Thanks for the help !

 

Did you check the ECT correction tables?

Untouched ect correction table + 1000cc injectors might give you this problem.

 

After running car (Get therm to open) Let car sit..... Start again, does it misfire a TAD (ALMOST like a dead hole) on restart for a second and then clearup?

 

Inj mfg? Fpr? Fuel pressure? And open your plug gaps around 18 or so 10 is way too tight

 

I have zero'd out all the correction tables.

DEF NOT like a dead cyl. One pull will be fine for longer rpm range, the next will breakup sooner. Almost like if the coil is getting hot/weak.

We started at .022 gap and worked our way down to confirm not a spark blowout issue.

 

make sure the fuel pressure is in good shape.

also, try a pull without vtec (set vtec at like 8,000)

clean out vtec solenoid screen

check oil/replace... perhaps there is alot of fuel in the oil

 

Sound like a boost cut

 

i chased a miss for a long time similar to yours, and it ended up being the center bolt on my intake cam had come loose. it wasn't loose enough to see at a glance, but it let the intake cam move in the gear. the rpm graph on my log wasn't smooth. i ended up replacing the intake cam and using thread lock on my cam bolts. the rpm graph led me to check rotor button, all secondary ignition componants, and cam timing but i still didn't catch the loose cam bolt. lol. anyway maybe this will help, if not good luck.

 

Sounds fuel related to me. Still haven't said what.mfg inj and fpr and.psi you run.

 

have you tried swaping distributors? new coil? have had several issues on dynos with factory dis. and with the msd dis. always had luck with spraying out dis with electrical cleaner ( blow out very well when done!) cap will explode if you dont! always get rid of factory coil and run eccel if you dont already have one

 

I have tried vtec off and same results, confirmed with oil pressure guage at head port 80psi steady during enguagement. Also checked with voltage meter and confirmed signal is not dropping to vts. I will do an oil change today and have car back on dyno tonight. Ialso will be looking at the flex pipe as mentioned earlier.


def not boost cut. Verified through ems.


This sounds similar to an issue i was experiencing also on another car where the cam broke where the distributor slid in and caused misfires. Checked and nothing of the sort. I will check the center bolt of the cams today too.

I have a smooth flat 11.3-11.5 afr curve and hv confirmed fpr is working properly. I have a base pressure of 48 and climbs in boost. DOES NOT drop at all. AEM rail and AEM fpr.

I am trying bnib distributor today.

Thanks for everyones help ! I appreciate all the suggestions !

 

I am trying bnib distributor today.

Thanks for everyones help ! I appreciate all the suggestions ! [/QUOTE]

i dont recomend aftermarket. nothing but problems with them. its a little more money but if your gonna run a dis i would rec a new honda dis sub assembly. with a new honda ignitor and a accel internal coil. you do this and you wont regret it. best purches i made on my old setup. never had a ignition issue again. but goodluck with it. misfires suck!

 

is your speedometer working ?

 

Just for ***** and giggles, trace back all injector wiring to ECU to make sure all outputs are to the correct injector.

 

When you tried the different S300 was it in a different ECU or just installed in yours?

 

Post a screen shot of your high and low cam IG tables.

 

A data log screen shot on the break up area we help a lot.

 

What fuel are you using?

 

Everytime i have ever had "misfires" on the dyno and at the track it has always been simply not enough timing.

 

While i wouldnt agree with that as an everytime thing i do think 17* is low for 380hp i stay around mid 20s up to 5-600ish hp depending what its asking for and depending what fuel.

 

i give up on asking what parts you run. why ask for help if you cant answer questions?

try 40 psi. base if runnning balland seat or pentil style inj. and check your aem fpr for the largest return orfice as well. that will cause quite a bit of dead time on the injector under 1:1 ratio in boost. this isnt happening without boost right?