Losing boost at 6400rpm. Help!

[juhanis]

alright. time for an update. i installed all my piggybacks onto the boomslang harness. the all of my grounds were re distributed and were properly installed. all connections were re soldered. i drove it, and the damn problem happened again. so, today i did one last measure. i installed my box which i named the "nms blackbox" with the flick of a switch the car goes into open loop. also, i fixed one wire, the tach signal going into my hks vpc, because it wasnt plugging in that well into the 9pin harness. i tried some 140mph pulls with the nms blackbox on, and it wasnt cutting out. then i tried some more with the box off, either way, no cutting. it worked well enough to make me think that i may have fixed the problem. the car will be going to the drag strip on wednesday, so, we'll see how it does. so far so well. i coasted 13flat last time at 95mph haha.

 

[suprahero]

Sounds good. I still haven't checked my wiring again, but I will soon. Thanks for the update.

 

[juhanis]

The good news is that so far through some research I think I found my problem. The bad news is that I think it was fuel cut... Lame. But yeah some safc tweaking has solved the issuem. Well so far.

 

[suprahero]

Mine is definately not fuel cut because I never feel it losing boost and boost/ fuel cut is definately something you feel when it happens. I'm glad you got yours fixed though.

 

[juhanis]

Mine is definately not fuel cut because I never feel it losing boost and boost/ fuel cut is definately something you feel when it happens. I'm glad you got yours fixed though.

is there a way for you to datalog the voltages on your sensors? because what i would do is look over the datalog when that issue is happening, and i'd see if any of the sensor readings seem to jump unexpectedly i'm sure you've also gone over your wiring. i'm not sure if my hooptie is fixed yet, but so far so good. as soon as my equips went back on, the car starts to behave... odd stuff.

 

[suprahero]

Do you have any more pictures of your car posted anywhere?

I'm going to work on mine this weekend and see what I can find. I'm going to recheck all of my wiring. Thanks for the input.

 

[juhanis]

Do you have any more pictures of your car posted anywhere?

I'm going to work on mine this weekend and see what I can find. I'm going to recheck all of my wiring. Thanks for the input.

Were you asking if there were more pics of my car?

 

[ForcedTorque]

Were you asking if there were more pics of my car?

Just a guess, but you two are the only people on this page (before this post), and Jay has posted that he loves your car. I agree with that as well.

 

[suprahero]

Were you asking if there were more pics of my car?

Just a guess, but you two are the only people on this page (before this post), and Jay has posted that he loves your car. I agree with that as well.

Ding ding ding...........we have a winner............:biglaugh:

 

[juhanis]

hehehe smartasses =P here ya go.

when the 69mm masterpower turbo was in

side profile

frontish

back (the exhaust is a stock catback with a 3" cutout)

 

[suprahero]

That is beautiful sir...............:love:

Update

I think I've found my problem. I took my car to a not so local shop (2 hours away) and we put it on the dyno. On the very first pull the guy swears he hears my valves floating or staying open, whatever you want to call it. I have the new pt67 installed and you can definately hear it now. With the 35r I couldn't hear it. The thing showed a constant boost pressure of 13psi which I guess is the magic number for the valves to stay kept open and the air is flowing straight through the intake and out the exhaust..........I dont know how the head works, but that seems to be what is happening and that's where my boost is going. I'm removing the head right now and I"m going to take it and have the seat pressure checked to make sure it's what Crower calls for. I googled it and came up with 1.325" @ 80lbs / open .980" @ 158lbs. coil bind .810
I'm going to go get the numbers off of my Crower box and cross reference it to make sure they're the same for my 1jz springs and retainers.

Just thought I'd let you guys know what's been happening. Hopefully this will fix it and thanks again for all of your help.

P.S......the car made 413rwhp @ 13psi.

 

[Tire Shredder]

sounds good. what are your air fuel ratio's like when the boost is "lost" you should see some result on a wideband at that point if your hypothesis is true...from the fresh charged air going out the exhaust.

 

[IJ.]

How so Steve it's still injecting fuel?

J: Only thing that made sense to me so <fingers crossed>
(called it awhile back but new springs had me doubting my diagnosis)

 

[ForcedTorque]

Jay, post some info on this dyno shop please. If it's 2 hours south of you, it may be close enough for me to go to as well. Patrick sure spoke highly of them. The only tuner I know down here scared me when he didn't even want to attempt to fool with my timing. Maybe he was right about dyno time being too expensive for that, but from my newfound experience, it's not that hard.

 

[suprahero]

How so Steve it's still injecting fuel?

J: Only thing that made sense to me so <fingers crossed>
(called it awhile back but new springs had me doubting my diagnosis)

Yeah, I remembered you mentioning it. That's why I sent you the first pm letting you know that I think I'd found the culprit.

Jay, post some info on this dyno shop please. If it's 2 hours south of you, it may be close enough for me to go to as well. Patrick sure spoke highly of them. The only tuner I know down here scared me when he didn't even want to attempt to fool with my timing. Maybe he was right about dyno time being too expensive for that, but from my newfound experience, it's not that hard.

Here is there website Scott. It's really south east of me, so it's still not going to be close to you.
http://huxracingusa.com/huxweb.htm

They have some really nice MR2's there. His wife's runs 12.20 @ 120mph with her driving it.

TS, I don't KNOW that this is going to fix it, but it's the only hope I have right now. Thanks.

 

[IJ.]

Easy fix if that's the problem J!
(can't understand how they could get it wrong though, only thing that makes sense is the wrong set of springs and they weren't checked for seat pressure before assembly)

 

[suprahero]

Here's what my car looks like...............AGAIN!!!!!!!

I'm taking it to the machine shop tomorrow. I'll be picking it up thursday, but I can't put it back together until my new gasket set arrives. I've reused these cam gears and gaskets for a while now. I think it's time to replace them.

Ian, do you know where the write up is of how to clean the metal head gasket. I remember reading it on here. Someone can just tell me how to clean it if they know. Thanks. If not, I'll look it up. I know it's on here somewhere.

 

[suprahero]

Easy fix if that's the problem J!
(can't understand how they could get it wrong though, only thing that makes sense is the wrong set of springs and they weren't checked for seat pressure before assembly)

Well, I cross referenced the box that they came in and they're for the 2jz head. I have the 1jz head and I think the valves are different lengths. I ordered them from Zazzn and he sold them to me as 1jz upgraded valves and springs. If the machinist can't make them work then I still have my stock springs and retainers that worked flawlessly on my first build. I can reuse them until I decide I need some stronger ones. I'll let you know what he saids after he looks at it and measures everything.

 

[IJ.]

Here ya go

 

[suprahero]

:bowdown:.......:love:.......:wave:.......