BoostAndBoobs

Hey guys, as always I have searched my problem previously, but I am just getting VTEC engines with this problem. Like VTEC isnt engaging correctly in boost and what not. I've got an LS falling on its face at full boost at like 5-6K. It sputters very badly. Spools as it should. Boost comes in nice and smooth. Wastegate opens properly. But once you hit full boost in the higher ranges like 5-6K is sputters almost like a rev limiter.

Not really sure where to begin. I tightened up the BOV a bit because maybe it was too soft and started leaking during boost. No luck.

Anyone think fuel problems? Timing? Spark blow out? Fouled plugs?

This thing runs great just cruising. But it does belt out the fuel smoke at half throttle or more. Maybe just too much fuel.

Note, I did just got done replacing the headgasket, new head, and rebuilt the entire top end while I was in there. New valve seals and all. The thing about it is it started this right before I tore it apart. So I really don't think timing as it hasn't been touched since the dyno tune (before headgasket fix). But its possible.

I think it may be getting too much fuel because it backfires a decent amount when driving around when let off the throttle.

B18B1 tuned on Neptune 10 PSI on July 10, 2015. If you need info on my setup just ask. Just trying to get opinions before I dump money into solutions over something stupid.

Schister66

Do you have a wideband? If so, do you track AFRs?

Also, which plugs are you running and what are they gapped to? When were they last changed? Checked?

Anything additional on the ignition system we should know about? Is it stock?

My first thought is spark blowout. It tends to happen at full boost just as you're describing.

BoostAndBoobs

That's my first thought as well. No, I actually do not have a wideband. I am going to be getting one soon. Pretty sure its stock ignition, as it does have an MSD box but I do not think its hooked up. I changed them right before I realized the headgasket was blown, maybe I gapped them wrong too? Not sure what they are gapped at, I just put them in there pretty snug just to see if the car would run correctly after the gasket change.
Forgot to gap them. Opinions on what they should be gapped to? Im running BKE 7E.

I will update as im at work, and will probably pull plugs on my lunch break.

Schister66

BKR7e's are the correct plug. I used to gap mine around .030" at ~400whp and that worked just fine. You may have to play with the gap if it doesn't solve the problem entirely the first time.

As for the wideband, if you trust your tuner (as I did), then there's no point in running one. I daily'd my boosted GSR for 4ish years and never once had a wideband in it. Not saying its necessary, just that it'd lend some insight on that end of the problem and possibly rule out rich/lean conditions

BoostAndBoobs

Sorry, I meant BKR 7E. Sorry, my mistake on that typo. But is there any difference between BKR 7E, and BKR 7E-11. So gap around .30?

Schister66

I knew what you meant. To be honest, i didnt read it the way you wrote it - I read "BKR7e" because it's ingrained in my head that way

https://honda-tech.com/forums/forced...turbo-2238538/

BoostAndBoobs

Thanks for all your help man! So my plugs are gapped at .44.

Schister66

No problem - hope this fixes the issue for you

2kdrift

try .025 - .028 definitely sounds like blow out, I was running the 7e's with no problem at .028 and also .030, OEM ignition with brand new coil.

My tuner wants me to use the NGK 4554 which is a non resistor plug, installed yesterday get Retuned this weekend so far they work good

you can never rely on the factory gap anyway, its rarely consistent even within the same package, the 4554's that I opened yesterday one was about .002 from the rest

BoostAndBoobs

To all:

The problem is now fixed!

Yes it was indeed spark blowout!

Got a new set of BKR7E for $9 and delivered to me from advanced. (The joys of working at a Dealer in Parts lol)

But yes, gapped them to .030" and dropped 'em in. Put it in second, got to 4k, and put my foot to the floor. The results? I almost wrecked. That thing pulls way harder than I remember. Wheels broke loose and torque steer almost in a ditch lol. Thanks to you guys. Hopefully future LS-T or turbo Honda owners read this thread if they have this problem.