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Wot pop/cut out at shift

DaytonaGTP500

DaytonaGTP500

New member
Ok so im chasing down a problem and im clueless right now with it. Under wot right at about shift my car will pop/blow air and will kick up about 6.5 knock on my scan gauge and u feal a noticeable loss of power and the car takes a sec to recover. I also noticed that my valve cover gaskets are both leaking pretty good(idk if that has anything to do with it a friend said it might be to much crankcase pressure) my current mods are zzp fullsize intercooler, ported lim/sc, speed daddy headers no cat or res and magnaflow mufflers, 1.9 modded rockers, zzp1.0 pcm, and a 3.1 pulley. Idk if the pcv could be bad causing this not venting the crank or burst kr(which im still learning wut it is) or wtf, any help is appreciated thanks
 
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Have you tried a crank case breather yet?

I kinda sounds like boost bypass. What does the boost gauge look like when this happens?
 
Ok so I jus went for a test drive to check boost and needless to say I'm even more lost because it didnt do it this time. The only thing I could think of is its alot cooler today and the car was cold too and everytime I notice it the engine was already war m. This time boost just went from 10.4 and droped to 8.2 at shift but I couldn't get it warm because as my luck is it started raining when I left the gas station right as it was heating upso idk can heat make the boost bypass screw up? And no I haven't tried a crank vent but now im thinkin that prolly aint my prob
 
DaytonaGTP500 said:
Ok so I jus went for a test drive to check boost and needless to say I'm even more lost because it didnt do it this time. The only thing I could think of is its alot cooler today and the car was cold too and everytime I notice it the engine was already war m. This time boost just went from 10.4 and droped to 8.2 at shift but I couldn't get it warm because as my luck is it started raining when I left the gas station right as it was heating upso idk can heat make the boost bypass screw up? And no I haven't tried a crank vent but now im thinkin that prolly aint my prob
Click to expand...

I really can't tell with the info given but the 10.4 to 8.2 looks about right for a shift. The KR may be false due to induction system problems. A video may help.

I'm sure someone has seen this before...just a matter of time 'til that person responds.

Sorry I cannot be of further assistance.
 
Its shifting at about 6k maybe just a little less, and no like a dumb ass I didnt I wasnt sure how to do them on the car or what size I wanted because I was wantin a cam over the winter but did a intercooler instead. And a lil off subject but can u do them on the car, how hard, and what size would I want? And also will that change drivability and how?(ibe honestly never looked that deep into springs sry lol) Its my dd but I take it to the track pry once or twice a month
 


I'm assuming that Z34phoenix is referring to inadequate spring pressure i.e. float due to boost pressure on the back of the valve.

Will the car do the same with the larger pulley on it...maybe a 3.4 or so?
 
well needless to say right now the car is down with a f'd up s/c. I got into it the other day tho and somehow someway the car didnt make the sound or kick up any kr, i tried a couple of different times to see if i could get it to do it and i couldn't. but then i noticed the s/c was makin a funny noise and when i checked it out i realized that the rotor pack was chipped on the side with needle bearings and when i put my old rotor pack(out of my old s/c) in the ported housing (from zzp) they felt fine till they was torqued down and now you can feal them rub when u spin it by hand(any ideas on that? lol). no clue whats goin on so i gotta get that prob fixed and then ill post again if its still doin it. thanks for all the help tho guys very much appreciated.
 
OK so I know this post is a lil old but I took my ported s/c and put my 3.2 pulley back on my car and last night raced a stupid Honda for fun and needless to say it did that pop worse than ever it actually felt like my car missed a shift and almost ****ing died too, and this has happend all the time right at shift points. Now does that seem more like valve float or a tranny prob?
 
and go figure i went out with the phone video to try n get it and nothing, it popped the first time but my video couldnt pick it up i drove it for like an hour wot the whole time and it wouldnt do it like it did last night. i have a video of when it was doin it the first time, then it was makin the noise and loose power rather noticeably and kick up 6.5 knock but again it would shift and drive back off like normal
 


****y video i was gunna get one of my speedo and **** but once again we would jus randomly roll the video to see if we could get it and that was about the only time sry lol
 
It is tough to tell from that vid. I almost wanted to think that it was mounts etc from the vid.

Do you have upgraded or known good mounts?
 
Ummm about 5 or 6 months ago I replaced the trans and lower mount with the napa ones but nothing special jus the OE part, do you really think mounts could be causing all the issues im having? I did notice last night that I was only able to get it to do it in performance shift mode (with the zzp pcm) and I went from a 3.1 to a 3.2 and its still doin it almost just as bad and it has been rather cooler at night then during the day. I was thinkin valve springs or injectors or ****y tune but yea I have no clue
 
Also could an exaust leak cause my problem? I have speed daddy headers and still haven't replaced that flex yet. Im pretty sure im hearing it leaking but my exaust guy is sayin he dont think so he thinks there headers are jus echoing like crazy and thats the noise IM hearing because there not wrapped.
 
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