Honda_Lover

Hey guys,
I have a problem with a S2000 from a friend of mine.
The car is a 2007 EU version with a TTS rotrex kit, so still the 2,0 engine.
It starts to hesitate at around 8500 rpm.

Made a short video, so you can see what is the problem:
Youtube Video

Things I tried / changed:
- installed the return fuel system from SOS
- changed spark plugs and ignition coils
- new oem cam sensor
- new hondata map senor
- switched off some functions in the ecu like oil pressure switch for example

Anyone ever had this problem?
I dont know what else i could do...

Hoping to get some help,
thanks
Patrick

Charper732

if your plugs are at the stock gap, try reducing it. .025" is a good place to start. If that doesn't fix the issue then the gap is not the problem

AP1Chief

what software are you tuned on? Kinda sounds like spark blow out, I would gap plugs down like he said, and see what it does.

Honda_Lover

Thank you guys, problem solved.
Gapped the plugs and hesitation is gone.
I never thought this could be the problem, because my own s2000 has 6 psi more boost with the same plugs and the stock gap.
Anyways, thank you again =)

AP1Chief

Np

RolanTHUNDER

You should run NGK Iridium BKR8EIX. No need to gap them as they're already tighter than stock PFR7's (assuming that's what you were running when the hesitation occurred)? They're one step colder as well which helps in a boosted environment.

Honda_Lover

The BKR8EIX are already installed.

06S2k07Si

Just FYI...

Age of ignition coils can play into this quite a bit...ambient temperature can play into this very notably as well. As the ambient temperature gets colder the air gets more dense and the energy required to jump the gap increases.

For one point of reference...

My 2006 had several iterations of supercharger kits over the years. When it was on the original Krafwerks kit (C30-94 blower) things were initially fine at right around 10psi of boost with .032" of gap. As the temperature dropped below approximately 40 degrees Fahrenheit I would get some breakup up north of 7k ish rpm. I lowered the gap to .026" and it completely went away...all on 93 octane. When we installed the first iteration of my TTS kit (C38-92 blower) around 16psi it needed .024" gap...until the temp got below around 40 degrees Fahrenheit...breakup started and we dropped it to .022" and again the problem dissapeared. When we reworked all of the piping and the boost increased to 17-18psi it needed .020" all still on 93 octane fuel...until we retuned it on E85 and it wanted .018". All with the same BKR8EIX plugs. Today it still is at .018" on E85 and seems fine. This is all on my car which I am the original owner. The first kit was installed at just over 5800mi and now has 29,000mi. All still with the original OEM ignition system and coils.

I hope this helps.

Brian

RolanTHUNDER

Great.

RolanTHUNDER

Glad to hear details like these, thanks. So basically with more boost, the tighter the spark plug gap should be. So you reckon at 10psi the standard BKR8EIX gap was sufficient?
And your OEM coils are still quite new so no surprises about their state of health there. Makes me think I should definitely change my 107k miles +- AP1 coils for new AP2 versions before I install my Vortech supercharger. Maybe they'll make a slight difference now whilst I'm NA modded.