TG160 and boost cut

[god910]

I'm going to the Muncie Dragway tomorrow to run the auto, and I fixed my vac. hose popping off the booster w/ a hose clamp, but I'm still having a problem that will hinder performance. When I get up in revs. (4500 or so) the boost is way up there on the stock gauge (almost all the way up) I am getting a miss, it seems to be a multiple (like ALL 6) cylinder misfire. I'm just wondering what the JeffM boost cut feels/sounds like. My 5 speed chip just shuts off, but w/ the boost going so high, I am lead to believe that it may be boost cut. The car runs great upto that point. Anybody that has hit the boost cut w/ this chip, could ya tell me if it's like what I have described. I can't go full throttle, I have to hold back a bit, and I'm at a loss as to what the problem is. I know my times will be slow tomorrow because of that. It pisses me off. Anyhow, TIA.

[dbtk2]

I'm going to the Muncie Dragway tomorrow to run the auto, and I fixed my vac. hose popping off the booster w/ a hose clamp, but I'm still having a problem that will hinder performance. When I get up in revs. (4500 or so) the boost is way up there on the stock gauge (almost all the way up) I am getting a miss, it seems to be a multiple (like ALL 6) cylinder misfire. I'm just wondering what the JeffM boost cut feels/sounds like. My 5 speed chip just shuts off, but w/ the boost going so high, I am lead to believe that it may be boost cut. The car runs great upto that point. Anybody that has hit the boost cut w/ this chip, could ya tell me if it's like what I have described. I can't go full throttle, I have to hold back a bit, and I'm at a loss as to what the problem is. I know my times will be slow tomorrow because of that. It pisses me off. Anyhow, TIA.

 

That is the boost cut. It is basically like a rev limiter type thing. The stock cut is completely different and is like you described with your 5 speed where the whole thing shuts off.

 

Make sure all the vacuum lines are connected properly, and I would check to see if your boost controller is in proper working order.

 

Shawn

[TurboGTU]

What you describe is exacly what im having truble with in the upper rpm, high boost, high load situations. At about 4500rpm and 10-11psi it acts like it pulls alot of timming off or something....not a shutting off thing ...but like it pulls alot of timming off. I think its the turbo ineficiancy. I don't have an intercooler...so thats my problem...too much heat. You however do. I tried remeding it by pulling off timming on the upper rpm but still the same thing. I have even rised boost cut to 13.5 to no avail thinking its boost cut. Ask the other guys who are running high boost if they have th same problem...like Luke. Im going to run 7psi above 4500rpm to see if that works with better timming. I'll run race gas with the 10psi chip to see if that cures it...if it does... :?

[god910]

Well, I'm going to the strip tonight, so I'm gonna pull my plugs today and put new one's in (if it's needed) and check the plug wires. I really don't know what else to do. I'm just gonna have to run part throttle, and hope for a decent time. And Jeff mentioned something in a PM that I didn't think about, the SES light doesn't come on, so it's not my boost cut, it just feels like a multicylinder misfire. I REALLY need to get a boost gauge on it to see what my actual boost it, and then I'm gonna look at the timing. probably just replace everything. (CPS, at the very least, you can never replace that thing too often )

[skalor]

As Jeff probably said, if there's no SES light and no code 31(IIRC) then it's not the boost cut. This is odd because I was getting on my car a little last night in 3rd and it felt like it hit overboost, but the light never came on. I was running my TopGun160 chip as well, and I was thinking that it might be related to that. I've found that the TopGun160 chip's idle is high enough not to cause 5 speed stalling issues. I'm still in the process of breaking in my clutch(about 250 miles so far) so I rolled on it about 3/4 of the way in 3rd, and she just cut out completely at one point. I've hit overboost before and this felt the same way, but like I said the light did not come on. I'm still using the factory boost control solenoid so it should be fine. I'm going to double check the MAP sensor and a couple of other vacuum lines to make sure that isn't my problem. I also have a new set of plugs and a set of the Taylor Spiro-pro wires that I can put on as well to see if it helps.

[dbtk2]

As Jeff probably said, if there's no SES light and no code 31(IIRC) then it's not the boost cut. This is odd because I was getting on my car a little last night in 3rd and it felt like it hit overboost, but the light never came on. I was running my TopGun160 chip as well, and I was thinking that it might be related to that. I've found that the TopGun160 chip's idle is high enough not to cause 5 speed stalling issues. I'm still in the process of breaking in my clutch(about 250 miles so far) so I rolled on it about 3/4 of the way in 3rd, and she just cut out completely at one point. I've hit overboost before and this felt the same way, but like I said the light did not come on. I'm still using the factory boost control solenoid so it should be fine. I'm going to double check the MAP sensor and a couple of other vacuum lines to make sure that isn't my problem. I also have a new set of plugs and a set of the Taylor Spiro-pro wires that I can put on as well to see if it helps.

 

What you're experiencing doesn't sound like the boost cut to me. The boost cut kind of feels like a rev limter and multiple misfires at the same time. It isn't like the stock boost cut where the whole engine pretty much dies. I have hit boost cut in both the STE (stock chip) and TGP (topgun 160) and they are completely different. However, I don't for some reason remember the SES light coming on in the TGP, although it may have and I just didn't notice it. But the boost cuts are completely different between the two chips.

 

Shawn