:::RHMT::: Real Home Made Turbo

General Category => Forced Induction => Topic started by: boosted15 on August 03, 2009, 04:08:18 AM

Title: odd studder in high rpm
Post by: boosted15 on August 03, 2009, 04:08:18 AM

I'm still fairly new to boost - I've had my d15b vtec on 7psi for a few months now. Sometimes, especially on an uphill onramp to a highway, at about 6k it feels like I hit rev limiter. It does not feel like a misfire at all. This has only happened maybe 3 or 4 times since May, and only in 3rd gear around 6k. It is a completely stock D15B with a 14b turbo running crome with a map that was tuned for a Z6 with a 14b. I know it is a tad rich, due to the big black cloud when I hit boost. I dont know what it feels like, but could the spark be getting blown out? I'll check my plug gap again tomorrow, they were set at .38 last time they were out.

Dunno at this point, slightly confused :P

(https://realhomemadeturbo.com/forum/proxy.php?request=http%3A%2F%2Fqudt.web-log.nl%2Fphotos%2Funcategorized%2Fshay_laren_04.jpg&hash=d3978c03784929e48c2b3885bbad5ae1e9b47370)

Title: Re: odd studder in high rpm
Post by: boosted 00 black si on August 03, 2009, 09:33:24 AM

dude gap ur plugs down to .29 - .30 and  why the hell do u have ur plugs gapped to .38???????

Title: Re: odd studder in high rpm
Post by: boosted15 on August 03, 2009, 05:11:38 PM

we didnt really know where to gap them to, so we figured .38 was better than stock  :-\

Title: Re: odd studder in high rpm
Post by: boosted 00 black si on August 03, 2009, 06:55:15 PM

 well regap them to what i told  u  n try that n see if that fix the problem

Title: Re: odd studder in high rpm
Post by: danz on August 03, 2009, 07:38:50 PM

also get fucked and get a tune

Title: Re: odd studder in high rpm
Post by: boosted15 on August 03, 2009, 11:08:12 PM

thanks for the advice guys, especially danz, getting fucked was the best thing i did all day  :noel:

Title: Re: odd studder in high rpm
Post by: That Guy on August 04, 2009, 03:26:04 AM

Yeah but getting a tune would be better in the long run  ;)

Title: Re: odd studder in high rpm
Post by: boosted15 on August 04, 2009, 03:48:49 PM

very true, but i dont plan on keeping this motor in there long so i cant justify spending the cash to have it tuned. it does run very well on the tune i have.

Title: Re: odd studder in high rpm
Post by: Urban Indian on August 04, 2009, 09:34:37 PM

change plugs


I have NGK number 7s in there right now gapped at .018


I had the SAME problem, changed plugs gapped lower. problem went away. I still have to buy cheeseburgers for random hero.....

Title: Re: odd studder in high rpm
Post by: QikEnuF on August 04, 2009, 09:40:05 PM

.38 is nuts...  Go lower

Title: Re: odd studder in high rpm
Post by: boosted15 on August 14, 2009, 03:42:07 AM

plugs now gapped at .020 down from .035 actually... problem solved

Title: Re: odd studder in high rpm
Post by: Urban Indian on August 14, 2009, 09:46:56 AM

you are welcome

Title: Re: odd studder in high rpm
Post by: HiProfile on August 15, 2009, 04:45:14 PM

People who can't grasp the concept that boost > NA will never realize that the quarter of a HP you loose from degapping your plugs is far less than if you encur the the wrath of misfire. It's more than made up for by the fact that your engine ignites the fuel a full 10-75% more. Small gap > misfire. Also having it super rich will make it harder to fire, another reason to reduce your gap.

Another thing to check is your timing. If you're getting a slight misfire and timing is too retarded, it will really seem fucked up.