My setup is pretty basic compared to most or all of this site. I'm basically a completely stock mustang with a DIY single turbo setup using flipped shorties sporting a small 58mm turbo. ECU tuned by local shop with SCT chip. TKO 500, 3:27 rear. Car made 385/435 with 8lbs on a mustang dyno.

I don't make it to the track often, mostly street driven. I've recently installed an Crane hi6-r with a 2 step to help build boost off the line and lower my 60ft. With it first set to 2800rpm then 3200rpms I get about 5 pounds of boost. My problem is after I deactivate the 2 step. The car pops, bangs, backfires and stumbles hard upon the release of the button. I have no current way of measuring what is going on since I'm not mapping or using any standalone system. Thought maybe someone could give me insight to what may be happening? Maybe it has been a problem for someone else as well?

First time out I had it wired through a switch on the center console and a line lock button on my shifter. That way they both had to be on to active it. On launch I could release the line lock and deactivate the 2 step. But it stumbled hard shifting into 2nd them would recover and stumble or back fire into 3rd. I thought maybe I was hitting the line lock button accidently when shifting. So the this week I removed it from the line lock and now only using a toggle switch on the center console. When launching I turn the switch off after releasing the clutch. But to my surprise it did the same thing. I intended to wire it to the clutch switch but would like to resolve the problem first.

Could it be loading up with fuel? Is there something else I should be doing when the 2 step is activated. The car runs hard on the street and on track without using the 2 step. Just can't build boost off the line, no real boost till 2nd gear. The problem only happens when using and releasing the 2 step.

Thanks

 

I'd say either your timing is doing something wacky when the 2 step comes off, or your fuel system is getting maxed out. Are you running a wideband?? It would tell you A LOT about what's going on if you did.........

 

I dont run a wideband. Car was tuned with one obviously but not one on the car. The only extra gauge Im rocking is a boost gauge. The fuel system is almost the norm for base turbos. 42lbers 80mm pmas 255lph 1:1regulator stock rails. But my car is only making a little 385hp. It runs great normal and hard. It will move fine out of the box if I just hold the rpms with my foot on a luanch and drop the clutch. but when ever I activate the 2 step it works fine and sounds normal and builds boost. When I let go of the button it is where the problem starts.

I questioned the timing myself. I dont know what is in the tune but I believe it is topped out at 17* or 18* at full boost. Question? the motor really isnt under load when 2 stepping, Sure it sees boost but could the timing still be full out at that point? (like 32* when cruising) I guess I could watch the timing with a light while someone else hits the 2 step and see were it goes. Im guess if its at full timing and 2 stepping it not a good combination when I let go?

How much timing should I have during the activation of the 2 step? I can activate a retard function at the same time if I need to or would it be easier to set my base timing to 17* at the track and pull the TFI plug? (88lx Mustang)

 

Not exactly, I run a Crane hi-6r ignition box that has a 2 step integrated into. The way it was first wired up was through a toggle switch in series with my line lock button on my shifter ball. So to activate it I first had to flip the toggle switch on. That way I could still use the line lock separate. Once the toggle was on I then use the momentary switch of the line lock to activate the 2 step. I would simply hold it down until the 3rd amber on the tree and slip the clutch and release the button at the same time. First time out I thought maybe I was hitting the button on the shifter (5speed) when shifting and actually activating the 2 step on accident. So before going back out this time I removed it from the momentary switch for the lock and only activate it from the toggle. So when I leave the burn out box I flip the switch on. stage and gas it. when the 3rd amber hits I release the clutch and flip the toggle switch off.

While on the 2 step the car builds about 5psi. I have full exhaust so it is much quieter and less violent than most 2 step I've hear. But it's what happens after the 2 step is deactivated is what got me lost. The car first leaves fine, than about 10-15 ft. out it falls on its face and pops and bangs bad. The first time it did it I thought for sure it just left a mess on the track and pulled over. To my surprise nothing was wrong when I got out. If I don't use the 2 step the car runs fine. Leaves the light clear just down on power since I don't really reach boost until it's time to shift to 2nd. I really need this 2 step to work out to get my 60ft down.

88lx stock mustang with single turbo with all supporting mods. SCT chip tune.

 

email my tuner back and fourth a few times. he adivsed me to try disconnecting my O2 sensors. and see if that helps eliminate the problem. does this sound like a feesable idea. right now best guess is maybe the unburnt fuel entering the exhaust is causing the O2s to try and compensate. I also read the Hi-6 instruction manual. they mention in some cases you may need to use a surge absorber on the 2 step power wirer. I may try that next if the O2 thing doesnt workout.

 

thanks for the responses. im hoping to get time tomorrow night to try it out. ill update with a resolve if I find it.

 

Well it may have been all for nothing. Not completely sure yet but it may have been the damn switch causing me the problem. Maybe some how it was shorting. Last night I thought I would change the style of the switch. Took the car out and launch a few times. Granted I cant get any traction on the street and it basically blew off the tires everytime. The car didnt not have any hickups coming off the 2 step. I still need to get it to hook off the line to see if its a load thing. but lastnight I was happy from what I was seeing. I will for now call it resloved unless it continues.

 

Maybe at the track when the car hooks well its uncovering the fuel pump/pick up ? Try adding more fuel to the tank ? I ran a Crane high six box many years ago in a truck I had, it gave me all kinds of trouble, the thing would get to 3000 rpm and the timing would jump all over the place , It was a NA FE engine, I deleted the box and just ran off the pertronix unit in the distributor and it ran great after that. I Put the box on another car and it did the same thing, I tossed it in the trash after that.

 

This is my 3rd crane box on a 3rd car. I have never had an issue with them, not saying thats not the case now. Im open to anything. But i switched to crane many years ago after two MSD boxes in a row' left me stranded in the middle of no where.

The gas thing I thought about the first time out but this last run at the track it shouldn't have been an issue. The last few trips I have just drove to the track which is nearly 50miles away. So I tried to fill up before and guess what I would need to get there and leave me light for racing. I failed hard, I tried to watch the gauge as I filled. With a delay in the gauge response I shut the gas off at half a tank but when I got back in the seat it was nearly full. I should have just based it off gallons. Stupid me. Anyhow once I got to the track it still left me with 3/4th of a tank of gas while racing.

But Like I said I havent ruled anything out yet but the switch. So I hope to get back to the track soon and test it out with good traction conditions.

 

I see my post made it look like I was bashing the crane box, sorry about that. I was just trying to give you feedback on what happened to me with one box, that does not mean all of them are bad for sure. Your right any electronic part can give you greif, Hope you get to the bottom of it, post up what you find, I have always liked diag. problems and the solutions.

 

No No I didnt take it like that at all. I was just trying to give you a brief history Ive had with crane or msd. I take all efforts and idea in to help find the problem. Thank you

I have taken it out to the street a few nights in a row. I have not had any problems with it since the switch was changed. Now I still need to get it to the track where I can get traction and load it up to see if thats the issue. But on the street Im not having a problem anymore. It was having problems on the street before the switch. Before it didnt matter if it was track or street. So Im hope its good just not sure till the track comes. I dont have plans to make it to the track till July 12th. I signed up for some brackets. So it will be a month before I get some finally results.

I can tell you right now I may need to upgrade my clutch soon if its worked out. My cutch is not liking the launch on boost. I can certainly smell the difference the few times I took it out. It has never had a problem hold the little power I make but it seems to be at its limit maybe in first taking off under boost.

 

Finally made it to the track last week to test the 2 step out. Clearly it was the damn switch the whole time. Zero problems this time when releasing the 2 step botton. Now I personally still need to work out my stagging steps and getting familar with the car. The 2 step worked as needed. I am sloppy on my prestaging steps and was not able to get into the 2 step long enough to get full bennefits from it. Im sure there I wasnt enough time to build all the boost it could. I usaully get to see about 5-6lbs. but I need to sit on it for 2-3 seconds. A few times I was slow on staging and the lights were already dropping on the tree before I had time to ingage the 2 step. But my last run of the night (2nd round)I was able to sit on the 2 step a little longer and pull a 1.7 60ft on nittos DRs. causing me to breakout on my et by 3 tenths. besting my overall. I hope to be able to lower that even more with practice to mid 1.6 60fts and get me into the 7's in the 1/8th with my completely stock car and my DIY small ass turbo setup.

Thanks everyone with the ideas and help above even thow it turned out to be this little thing and a lot less complicated than I origonally thought.